Hi ReLLaXX, and welcome to our thread !
I think I've understood all your words -"wnglish" for english seems more a finger slip, which I do too often with some other words.
Anything you want to post to tell us about, or photos to look at, will be most welcome.
There will be more information from me about getting the cross-overs working to close to original specification as soon as I have sufficient time available, and there will likely be more from the three 66 owners after they've had time to try the ideas posted to date.
I think I've understood all your words -"wnglish" for english seems more a finger slip, which I do too often with some other words.
Anything you want to post to tell us about, or photos to look at, will be most welcome.
There will be more information from me about getting the cross-overs working to close to original specification as soon as I have sufficient time available, and there will likely be more from the three 66 owners after they've had time to try the ideas posted to date.
Hi everyone /
Welcome Rellaxx
Alan--
24uf capacitor:
"check very closely the solder joints to all those 24uF and piggy-backed smaller caps, and compare the solder joints' colour , etc ... to the original solder joints around all the other components to see if its possible some were re-soldered later.".........
"another possible reason for the larger series capacitance to the MD500 in the 50watt version is that perhaps that version of the driver had a different Fs to the later 80watt version, and thus a slightly different Impedance around the 500Hz area, and/or a slightly different Frequency Response at the low end of its useable spectrum."
On all four crossovers, I couldn't discern any color differences in the solder joints. Moreover, the electrical tape that binds the capacitors seems to be original, uniform, and undisturbed. My overall impression is that the crossovers have not been altered or repaired.
Since one woodie crossover (with its 80watt midrange and 28uf cap) has a capacitor that is very close in value to the earlier blackies (with their 50watt midranges and 30uf caps), I wonder if Celestion was simply making adjustments at this crossover location as a response to damaged drivers that might have been showing up in their repair shop--before they ended up at the final 24uf value with the later woodies.
"check both vintages of woofers to see if any evidence on their labels, or stampings on their chassis or back of their cones, or simple visible differences in the front of their cones, of differences between the vintages."
When I purchased the blackies (advertised as being in excellent working condition) both arrived with damaged woofers. I ended up getting replacement woofers on ebay--a single woofer from a ditton 44, and two woofers (from either 44's or 66's) from another purchase. (Alan, you assisted me with this problem last summer).
Also, the dust caps on these replacement woofers are larger than on the originals; thus, they sit further towards the front of the cone, and reduce its apparent depth.
So, anyway, blackie's woofers are all mixed up now.
*************************
replacement caps:
...how you are going to fit the new caps on your old boards, because the Polypropylene caps, and anything else as good, are all larger size dimensions than those old Black electrolytics.
See post #115
***************************
erie & arco treble capacitors:
Eries---these are probably Paper-in-oil, and may still be OK if there is not evidence of substances leaking from within - look around where the leads connect to the body.
Arco---"as they are each 2.2uF, X2 = 4.4uF , instead of Celestion's 4uF, check their solder joints to see if original, or if evidence of later soldering - they could have been installed by a modifier or repairperson."
I didn't notice any leaks....all look original.
***************************
I hope to be getting some test equipment to measure the capacitance value and ESR (at 100 kHz, I think) on all the caps....I’ll let you know.
sba
Welcome Rellaxx
Alan--
24uf capacitor:
"check very closely the solder joints to all those 24uF and piggy-backed smaller caps, and compare the solder joints' colour , etc ... to the original solder joints around all the other components to see if its possible some were re-soldered later.".........
"another possible reason for the larger series capacitance to the MD500 in the 50watt version is that perhaps that version of the driver had a different Fs to the later 80watt version, and thus a slightly different Impedance around the 500Hz area, and/or a slightly different Frequency Response at the low end of its useable spectrum."
On all four crossovers, I couldn't discern any color differences in the solder joints. Moreover, the electrical tape that binds the capacitors seems to be original, uniform, and undisturbed. My overall impression is that the crossovers have not been altered or repaired.
Since one woodie crossover (with its 80watt midrange and 28uf cap) has a capacitor that is very close in value to the earlier blackies (with their 50watt midranges and 30uf caps), I wonder if Celestion was simply making adjustments at this crossover location as a response to damaged drivers that might have been showing up in their repair shop--before they ended up at the final 24uf value with the later woodies.
"check both vintages of woofers to see if any evidence on their labels, or stampings on their chassis or back of their cones, or simple visible differences in the front of their cones, of differences between the vintages."
When I purchased the blackies (advertised as being in excellent working condition) both arrived with damaged woofers. I ended up getting replacement woofers on ebay--a single woofer from a ditton 44, and two woofers (from either 44's or 66's) from another purchase. (Alan, you assisted me with this problem last summer).
Also, the dust caps on these replacement woofers are larger than on the originals; thus, they sit further towards the front of the cone, and reduce its apparent depth.
So, anyway, blackie's woofers are all mixed up now.
*************************
replacement caps:
...how you are going to fit the new caps on your old boards, because the Polypropylene caps, and anything else as good, are all larger size dimensions than those old Black electrolytics.
See post #115
***************************
erie & arco treble capacitors:
Eries---these are probably Paper-in-oil, and may still be OK if there is not evidence of substances leaking from within - look around where the leads connect to the body.
Arco---"as they are each 2.2uF, X2 = 4.4uF , instead of Celestion's 4uF, check their solder joints to see if original, or if evidence of later soldering - they could have been installed by a modifier or repairperson."
I didn't notice any leaks....all look original.
***************************
I hope to be getting some test equipment to measure the capacitance value and ESR (at 100 kHz, I think) on all the caps....I’ll let you know.
sba
the crumbling capacitors, etc ...
What has "crumbled" is at most simply the Insulation, and may be only the coating. You can check this easily with your multimeter in its Resistance function.
Do this test fairly quickly because with the very low resistances you will find, and the likelihood of the capacitors charging up, the battery in your meter will be supplying a lot of current thus may expire sooner than you expect.
Touch one probe to the exposed metal body of one of the Erie caps, and scratch it gently to expose clean metal for good electrical contact, but not so hard as to risk piercing it .
Touch the other probe to one of that caps leads and notice what first happens, and then notice if any other occurrence begins after a few seconds, then remove that probe and touch it to the other end of the cap's lead, and notice again, as before.
Do you get an almost zero resistance at one end, and does it remain at almost zero ?
At the other end, do you get a reading that is not stable, and which very soon starts to cause the digits on the meter to change as if something is electrically charging up ?
Try this with every cap in the treble sections of both Blackie cross-overs.
Next, are the now exposed metal bodies touching each other in each group of caps ?
IF you got a stable near zero resistance reading to one end of each cap, is that near zero resistance to the same end of each cap in each bunch ?
That is, you will see where all the leads from each cap in each bunch join together on the circuit board for each end of each bunch.
Basically, if all caps in each bunch give near zero resistance stabily to the same common point, and none do to the opposite end of the bunch common point, then you can still use those caps because there will be no short circuit.
The outer metal case is thus connected to the lead at the end where you get the near zero resistance reading.
If you got no stable near zero resistance readings for any of the caps, then it indicates the outer cases are simply cases and are not part of the electrical circuit.
In such case you should have seen a stable infinitely large resistance reading, or an Open Circuit reading
{unless your fingers of both hands were touching the metal of the both probes, in which case you would have been measring the high resistance of your body, hand to hand circuit}.
One problem will be if you get a stable near resistance reading between the metal body and both ends of any capacitor.
The only other circumstance that would prevent you being able to use those caps with insulation missing is if one is connected in the reverse direction to the others in its bunch AND has its exposed metal case touching one of the other caps exposed metal case.
Then you would have a Short Circuit, and should not use, unless you disconnect and reverse the direction of the particular capacitor.
____________________________________________________
That CCL 24uF 25 volt REV electrolytic capacitor :-
I think REV indicates REVERSABLE , and if so the cap is basically Bipolar and can be used in an AC circuit {such as the one it is currently in} with no regard to which direction it is connected in.
If it does have + and - markings on its case, then such would likely indicate the preferred direction for it to be connected if it is used in a cuircuit where there is both AC and DC voltages present simultaneously {or each at some time during the operating cycle of the circuit}.
Such is possible for some types of electrolytic capacitor internal construction.
A Polarized cap would not work there in a loudspeaker cross-over, BUT in this case the is a small bipolar cap connected in parrallel with it, thus that bipolar would obscure the partial malfunction of any Polar electro in parrallel with it.
Celestion would not have put a Polarized cap in there, thus it is either a Reversable electro, or a polar cap that some-one else has installed after it left Celestion premises.
I think you would have noticed a very different midrange sound from one Blackie to the other if that is a polarized cap !
sba said:
What has "crumbled" is at most simply the Insulation, and may be only the coating. You can check this easily with your multimeter in its Resistance function.
Do this test fairly quickly because with the very low resistances you will find, and the likelihood of the capacitors charging up, the battery in your meter will be supplying a lot of current thus may expire sooner than you expect.
Touch one probe to the exposed metal body of one of the Erie caps, and scratch it gently to expose clean metal for good electrical contact, but not so hard as to risk piercing it .
Touch the other probe to one of that caps leads and notice what first happens, and then notice if any other occurrence begins after a few seconds, then remove that probe and touch it to the other end of the cap's lead, and notice again, as before.
Do you get an almost zero resistance at one end, and does it remain at almost zero ?
At the other end, do you get a reading that is not stable, and which very soon starts to cause the digits on the meter to change as if something is electrically charging up ?
Try this with every cap in the treble sections of both Blackie cross-overs.
Next, are the now exposed metal bodies touching each other in each group of caps ?
IF you got a stable near zero resistance reading to one end of each cap, is that near zero resistance to the same end of each cap in each bunch ?
That is, you will see where all the leads from each cap in each bunch join together on the circuit board for each end of each bunch.
Basically, if all caps in each bunch give near zero resistance stabily to the same common point, and none do to the opposite end of the bunch common point, then you can still use those caps because there will be no short circuit.
The outer metal case is thus connected to the lead at the end where you get the near zero resistance reading.
If you got no stable near zero resistance readings for any of the caps, then it indicates the outer cases are simply cases and are not part of the electrical circuit.
In such case you should have seen a stable infinitely large resistance reading, or an Open Circuit reading
{unless your fingers of both hands were touching the metal of the both probes, in which case you would have been measring the high resistance of your body, hand to hand circuit}.
One problem will be if you get a stable near resistance reading between the metal body and both ends of any capacitor.
The only other circumstance that would prevent you being able to use those caps with insulation missing is if one is connected in the reverse direction to the others in its bunch AND has its exposed metal case touching one of the other caps exposed metal case.
Then you would have a Short Circuit, and should not use, unless you disconnect and reverse the direction of the particular capacitor.
____________________________________________________
That CCL 24uF 25 volt REV electrolytic capacitor :-
I think REV indicates REVERSABLE , and if so the cap is basically Bipolar and can be used in an AC circuit {such as the one it is currently in} with no regard to which direction it is connected in.
If it does have + and - markings on its case, then such would likely indicate the preferred direction for it to be connected if it is used in a cuircuit where there is both AC and DC voltages present simultaneously {or each at some time during the operating cycle of the circuit}.
Such is possible for some types of electrolytic capacitor internal construction.
A Polarized cap would not work there in a loudspeaker cross-over, BUT in this case the is a small bipolar cap connected in parrallel with it, thus that bipolar would obscure the partial malfunction of any Polar electro in parrallel with it.
Celestion would not have put a Polarized cap in there, thus it is either a Reversable electro, or a polar cap that some-one else has installed after it left Celestion premises.
I think you would have noticed a very different midrange sound from one Blackie to the other if that is a polarized cap !
Alan,
Better yet.....I'll get some capacitance values from those old crumbling Erie Research Technologies caps (in a week or two, when I get access to a meter). You're right, my horror at seeing all that cracked and crumbling insulation and in thinking that everything must be replaced, might turn out to be otherwise. It would be a pleasant surprise if all, or at least some of those Eries, can be re-used, since oil-impregnated metallized film caps are expensive to replace.
I've been reading more about caps, checking prices, and mulling over what sort of budget I have for all this.....four Ditton 66 crossovers plus....well, I just took a look inside my Dahlquist DQM-9's and noticed that there’s a total of eight, large-value, 25 year old electrolytic caps.
Until I measure all the caps, the following discussion is sort of premature, but my rough plan is to work on the blackie crossovers first. I'm assuming that all the large-value electrolytics will need to be replaced with metallized polypropylene (MKP). I’m pretty sure that I can make the adjustments needed to fit their larger size.
On another website, which has a group of people restoring AR speaker crossovers, the conclusion was that one of the most important things is to stick as close as possible to the original capacitance values (in doing so, minor variations in ESR become less important). So, in choosing cap replacements, I thought I should look for a 5% or better cap tolerance (but I really don't know....maybe 10% would be okay too). And since I'll also be measuring the new replacement caps to make sure I know what's going into the crossovers, I want to buy from someone who will easily accept returns if necessary. It looks like Parts Express and Parts Connexion have somewhat adequate return policies.
So, then....5% or better metallized polypropylene caps at PartsExpress or similar store: there's Axon, Jantzen (made in Poland), Solen (made in France), Bennic xpp, Dayton 1% (Bennic and Dayton made in China by same manf.) , and Audyn MKP. They all seem to be in the same price range. Clarity Cap (made in England) is more expensive.
For the two 72uf (and maybe the 24uf ) locations, I'm leaning towards Solen (using one 68uf and one 4uf). But I’m open to any suggestions.
The treble and midrange cap choices seem somewhat more complicated. I've read that dual-layer polypropylene film and foil cap construction produces the least inherent noise (noise is more evident in the standard single-layer metallized polypropylene caps, which invariably have noise-producing pinhole tears created in the film manufacturing process and/or in the cap winding process). Thus, in this regard, the film and foil caps are said to be well-suited for the treble and midrange circuits. So, if I had my druthers, I would use such film & foil caps (e.g., Audyn MKP plus 2%, Audiocap theta, Hovland Musicap), but their price is around seven to eight times greater than standard metallized polypropylene....Not really in my budget.
My hope, at the moment, is that the Erie caps from the two blackie crossover boards will turn out to be acceptable, and that I'll be able to spread them equally to the 6uf/4uf/4uf locations on all four of the crossover boards--making up the uf difference by bundling them to new metallized polypropylene, inexpensive film & foil, or inexpensive oil & paper.
Sba
Better yet.....I'll get some capacitance values from those old crumbling Erie Research Technologies caps (in a week or two, when I get access to a meter). You're right, my horror at seeing all that cracked and crumbling insulation and in thinking that everything must be replaced, might turn out to be otherwise. It would be a pleasant surprise if all, or at least some of those Eries, can be re-used, since oil-impregnated metallized film caps are expensive to replace.
I've been reading more about caps, checking prices, and mulling over what sort of budget I have for all this.....four Ditton 66 crossovers plus....well, I just took a look inside my Dahlquist DQM-9's and noticed that there’s a total of eight, large-value, 25 year old electrolytic caps.
Until I measure all the caps, the following discussion is sort of premature, but my rough plan is to work on the blackie crossovers first. I'm assuming that all the large-value electrolytics will need to be replaced with metallized polypropylene (MKP). I’m pretty sure that I can make the adjustments needed to fit their larger size.
On another website, which has a group of people restoring AR speaker crossovers, the conclusion was that one of the most important things is to stick as close as possible to the original capacitance values (in doing so, minor variations in ESR become less important). So, in choosing cap replacements, I thought I should look for a 5% or better cap tolerance (but I really don't know....maybe 10% would be okay too). And since I'll also be measuring the new replacement caps to make sure I know what's going into the crossovers, I want to buy from someone who will easily accept returns if necessary. It looks like Parts Express and Parts Connexion have somewhat adequate return policies.
So, then....5% or better metallized polypropylene caps at PartsExpress or similar store: there's Axon, Jantzen (made in Poland), Solen (made in France), Bennic xpp, Dayton 1% (Bennic and Dayton made in China by same manf.) , and Audyn MKP. They all seem to be in the same price range. Clarity Cap (made in England) is more expensive.
For the two 72uf (and maybe the 24uf ) locations, I'm leaning towards Solen (using one 68uf and one 4uf). But I’m open to any suggestions.
The treble and midrange cap choices seem somewhat more complicated. I've read that dual-layer polypropylene film and foil cap construction produces the least inherent noise (noise is more evident in the standard single-layer metallized polypropylene caps, which invariably have noise-producing pinhole tears created in the film manufacturing process and/or in the cap winding process). Thus, in this regard, the film and foil caps are said to be well-suited for the treble and midrange circuits. So, if I had my druthers, I would use such film & foil caps (e.g., Audyn MKP plus 2%, Audiocap theta, Hovland Musicap), but their price is around seven to eight times greater than standard metallized polypropylene....Not really in my budget.
My hope, at the moment, is that the Erie caps from the two blackie crossover boards will turn out to be acceptable, and that I'll be able to spread them equally to the 6uf/4uf/4uf locations on all four of the crossover boards--making up the uf difference by bundling them to new metallized polypropylene, inexpensive film & foil, or inexpensive oil & paper.
Sba
The meter arrived early.
Here are the capacitor readings from my four Celestion 66 crossovers:
* Crossovers are listed from oldest to newest (1-4) [1973-1977]
* ESR in ohms @ 100 kHz
* Out-of-circuit measurements made with a Peak Atlas esr60
*****************************************************
72 uf elcap 50v--
(a) location
blackie 1.......ESR= 0.12 / uf= 82.98
blackie 2.......ESR= 0.12 / uf= 77.72 --(two 30s & one 12 bundled)
woodie 3......ESR= 0.18 / uf= 85.96
woodie 4......ESR= 0.13 / uf= 86.05
(b) location
blackie 1.......ESR= 0.12 / uf= 69.27
blackie 2.......ESR= 0.14 / uf= 64.19 --(two 30s & one 12 bundled)
woodie 3......ESR= 0.20 / uf= 84.49
woodie 4......ESR= 0.12 / uf= 77.98
****************************************************
4 uf elcap 50v--
blackie 1.......ESR= 0.98 / uf= 3.72
blackie 2.......ESR= 1.22 / uf= 3.60
woodie 3......ESR= 2.80 / uf= 4.00
woodie 4......ESR= 0.89 / uf= 3.88
****************************************************
24 uf ccL 25v--
blackie 1.......ESR= 0.08 / uf= 25.94
blackie 2.......ESR= 0.10 / uf= 17.20
woodie 3......ESR= 0.10 / uf= 22.97
woodie 4......ESR= 0.09 / uf= 26.06 --(elcap 50v)
+ piggyback 6 uf elcap 50v on
blackie 1.......ESR= 0.65 / uf= 6.02
blackie 2.......ESR= 0.66 / uf= 5.91
+ piggyback 4 uf elcap 50v on
woodie 3.......ESR= 1.46 / uf= 3.99
= Summary at this location:
30uf blackie 1.......uf= 31.96
30uf blackie 2.......uf= 23.11
28uf woodie 3......uf= 26.96
24uf woodie 4......uf= 26.06
****************************************************
6 uf bundled treble cap location--
blackie 1.......ESR= 0.11 / uf= 3.95 --(three 2.0 Erie 150v)
...................ESR= 0.07 / uf= 2.94
...................ESR= 0.08 / uf= 2.21
blackie 2.......ESR= 0.08 / uf= 2.40 --(four 1.5 Erie 150v)
...................ESR= 0.09 / uf= 3.94
...................ESR= 0.09 / uf= 3.01
...................ESR= 0.10 / uf= 4.07
woodie 3......ESR= 0.06 / uf= 5.96 --(four 1.5 M312 erie 250v)
woodie 4......ESR= 0.06 / uf= 6.22 --(four 1.5 M312 erie 250v)
= Summary at this 6uf location:
blackie 1.......uf= 9.10
blackie 2.......uf= 13.42
woodie 3......uf= 5.96
woodie 4......uf= 6.22
****************************************************
4 uf bundled treble cap location--
blackie 1.......ESR= 0.08 / uf= 4.54 --(two 2.0 Erie 150v)
...................ESR= 0.10 / uf= 4.26
blackie 2.......ESR= 0.12 / uf= 2.20 --( two 2.2 Arco 100v)
...................ESR= 0.21 / uf= 2.14
woodie 3......ESR= 0.06 / uf= 3.81 -(two 1.5 / one 1.0 M312 erie 250v)
woodie 4......ESR= 0.05 / uf= 4.09 -(two 1.5 / one 1.0 M312 erie 250v)
= Summary at this 4 uf location:
blackie 1.......uf= 8.80
blackie 2.......uf= 4.34
woodie 3......uf= 3.81
woodie 4......uf= 4.09
****************************************************
Here are the capacitor readings from my four Celestion 66 crossovers:
* Crossovers are listed from oldest to newest (1-4) [1973-1977]
* ESR in ohms @ 100 kHz
* Out-of-circuit measurements made with a Peak Atlas esr60
*****************************************************
72 uf elcap 50v--
(a) location
blackie 1.......ESR= 0.12 / uf= 82.98
blackie 2.......ESR= 0.12 / uf= 77.72 --(two 30s & one 12 bundled)
woodie 3......ESR= 0.18 / uf= 85.96
woodie 4......ESR= 0.13 / uf= 86.05
(b) location
blackie 1.......ESR= 0.12 / uf= 69.27
blackie 2.......ESR= 0.14 / uf= 64.19 --(two 30s & one 12 bundled)
woodie 3......ESR= 0.20 / uf= 84.49
woodie 4......ESR= 0.12 / uf= 77.98
****************************************************
4 uf elcap 50v--
blackie 1.......ESR= 0.98 / uf= 3.72
blackie 2.......ESR= 1.22 / uf= 3.60
woodie 3......ESR= 2.80 / uf= 4.00
woodie 4......ESR= 0.89 / uf= 3.88
****************************************************
24 uf ccL 25v--
blackie 1.......ESR= 0.08 / uf= 25.94
blackie 2.......ESR= 0.10 / uf= 17.20
woodie 3......ESR= 0.10 / uf= 22.97
woodie 4......ESR= 0.09 / uf= 26.06 --(elcap 50v)
+ piggyback 6 uf elcap 50v on
blackie 1.......ESR= 0.65 / uf= 6.02
blackie 2.......ESR= 0.66 / uf= 5.91
+ piggyback 4 uf elcap 50v on
woodie 3.......ESR= 1.46 / uf= 3.99
= Summary at this location:
30uf blackie 1.......uf= 31.96
30uf blackie 2.......uf= 23.11
28uf woodie 3......uf= 26.96
24uf woodie 4......uf= 26.06
****************************************************
6 uf bundled treble cap location--
blackie 1.......ESR= 0.11 / uf= 3.95 --(three 2.0 Erie 150v)
...................ESR= 0.07 / uf= 2.94
...................ESR= 0.08 / uf= 2.21
blackie 2.......ESR= 0.08 / uf= 2.40 --(four 1.5 Erie 150v)
...................ESR= 0.09 / uf= 3.94
...................ESR= 0.09 / uf= 3.01
...................ESR= 0.10 / uf= 4.07
woodie 3......ESR= 0.06 / uf= 5.96 --(four 1.5 M312 erie 250v)
woodie 4......ESR= 0.06 / uf= 6.22 --(four 1.5 M312 erie 250v)
= Summary at this 6uf location:
blackie 1.......uf= 9.10
blackie 2.......uf= 13.42
woodie 3......uf= 5.96
woodie 4......uf= 6.22
****************************************************
4 uf bundled treble cap location--
blackie 1.......ESR= 0.08 / uf= 4.54 --(two 2.0 Erie 150v)
...................ESR= 0.10 / uf= 4.26
blackie 2.......ESR= 0.12 / uf= 2.20 --( two 2.2 Arco 100v)
...................ESR= 0.21 / uf= 2.14
woodie 3......ESR= 0.06 / uf= 3.81 -(two 1.5 / one 1.0 M312 erie 250v)
woodie 4......ESR= 0.05 / uf= 4.09 -(two 1.5 / one 1.0 M312 erie 250v)
= Summary at this 4 uf location:
blackie 1.......uf= 8.80
blackie 2.......uf= 4.34
woodie 3......uf= 3.81
woodie 4......uf= 4.09
****************************************************
old Capacitors and types of Leakage
Its good your Meter arrived, and some interesting results, but some of those should be interpreted with caution.
First, as you wrote :-
"Out of circuit measurements"
Do I understand correctly, did you disconnect every capacitor , and the in-bunch measured M312 Eries, from the circuit completely at at least one end ?
Any component connected in parallel with a capacitor will affect the meter reading, even the hand to hand finger flesh of your body.
I have heard of some types of Meters which can perform measurements with the circuit remaining connected, but I do not know of such for capacitance meters, nor can I think how such could be possible.
The 72 uF elcaps :- I am not surprized, even the largest measurement is only just under + 20%, and + or - 20 % is common for elcaps, and some have wider Tolerances.
BUT, before we consider most of the caps :-
Leakage affects measurements !
Leakage :- in the past few posts where I have suggested inspecting the cap bodies for signs of leakage, I was refering to physical leaks of substances,
{and it seems there are none from your caps, sba
other readers, check your caps visibly in the manner I explained in a previous Post}.
Now we have to take into account Electrical Leakage ,
that is leakage of Charge.
Basically if an electrically leaky cap is charged up to any Voltage and then disconnected from the circuit {quickly so that the circuit does not discharge it} it will discharge through itself.
All capacitors have some electrical leakage, but for some types it is miniscule, and thus not problem, and for other types, with small leakage, it is a problem in some types of circuits and not in other types of circuits.
Paper-in Oil caps do have noticeable electrical leakage.
Well manufactured ones do not have too much, but the leakage does increase if the cap becomes hot, and such does occur when it is pasing a lot of AC signal at frequencies where it has significant Impedance.
Leakage usually increases as caps age for types that have liquids or semi-liquids such as pastes inside.
This does not normally occur with caps that have only solids inside, unless they are damaged in some way whilst in or not in use.
Thus I doubt any of the plastic film type caps in these cross-overs will be leaking charge, but such can if a manufacturing fault or later damage {I have some such}.
The Electros and the presumed Paper-in-Oils will all leak most on first charge period after disuse, such as when you have measured them, particually those you have not been using such as the Blackies !
The degree of leakage I do not know.
My experience has been that an elecrtically leaking capacitor measures larger than it is when not leaking, and the degree larger seems to be related to the degree of leakage - larger produces larger.
More on this next time, plus some suggestions !
Its good your Meter arrived, and some interesting results, but some of those should be interpreted with caution.
First, as you wrote :-
"Out of circuit measurements"
Do I understand correctly, did you disconnect every capacitor , and the in-bunch measured M312 Eries, from the circuit completely at at least one end ?
Any component connected in parallel with a capacitor will affect the meter reading, even the hand to hand finger flesh of your body.
I have heard of some types of Meters which can perform measurements with the circuit remaining connected, but I do not know of such for capacitance meters, nor can I think how such could be possible.
The 72 uF elcaps :- I am not surprized, even the largest measurement is only just under + 20%, and + or - 20 % is common for elcaps, and some have wider Tolerances.
BUT, before we consider most of the caps :-
Leakage affects measurements !
Leakage :- in the past few posts where I have suggested inspecting the cap bodies for signs of leakage, I was refering to physical leaks of substances,
{and it seems there are none from your caps, sba
other readers, check your caps visibly in the manner I explained in a previous Post}.
Now we have to take into account Electrical Leakage ,
that is leakage of Charge.
Basically if an electrically leaky cap is charged up to any Voltage and then disconnected from the circuit {quickly so that the circuit does not discharge it} it will discharge through itself.
All capacitors have some electrical leakage, but for some types it is miniscule, and thus not problem, and for other types, with small leakage, it is a problem in some types of circuits and not in other types of circuits.
Paper-in Oil caps do have noticeable electrical leakage.
Well manufactured ones do not have too much, but the leakage does increase if the cap becomes hot, and such does occur when it is pasing a lot of AC signal at frequencies where it has significant Impedance.
Leakage usually increases as caps age for types that have liquids or semi-liquids such as pastes inside.
This does not normally occur with caps that have only solids inside, unless they are damaged in some way whilst in or not in use.
Thus I doubt any of the plastic film type caps in these cross-overs will be leaking charge, but such can if a manufacturing fault or later damage {I have some such}.
The Electros and the presumed Paper-in-Oils will all leak most on first charge period after disuse, such as when you have measured them, particually those you have not been using such as the Blackies !
The degree of leakage I do not know.
My experience has been that an elecrtically leaking capacitor measures larger than it is when not leaking, and the degree larger seems to be related to the degree of leakage - larger produces larger.
More on this next time, plus some suggestions !
Do I understand correctly, did you disconnect every capacitor , and the in-bunch measured M312 Eries, from the circuit completely at at least one end ?
I borrowed the meter from a friend of a friend. I was told that it's primarily an in-circuit ESR meter, but will also test for capacitance values (also in-circuit, according to the accompanying manual). ( I think the meter discharges the caps first.) But, after testing two caps in-circuit, I noticed that while the ESR part was working okay , the cap value readings were running amok into the hundreds of ufs.
So...I snipped a cap, pulled it out, attached the alligator clips (isolated, out-of-circuit, no hands touching), and pressed the test button. The results were good. It became a cap "demolition" project, where each cap was snipped and measured. After I had finished, I calibrated the meter and measured all the caps again. The results were almost identical.
I measured all the bundled caps together and then individually. The sum of the individuals equaled the bundled total; however, I thought it unnecessary to list individually those few bundled 72uf electros and Erie m312 polyesters.
On the other hand, the bundled Erie A304 and A316 were listed individually because, if they are in fact oil-impregnated metallized film caps (and somewhat stable), I would like to re-use them---one at each 4uf and 6uf treble location on all four crossovers (piggybacking something else to the Eries where necessary).
By any chance, do you know what that "A" stands for on the Erie caps? With the Erie M312's, I'm pretty sure that the "M" stands for Polyester.
*****************
I just made an impulse purchase of Solen caps!! I was going over my calculations again and realized that I had only budgeted for four 72ufs, instead of the required eight. After more price checking, I found Solen caps on sale for half the normal price at the Solen Canada web site. The catch is...it's existing stock of non environmentally friendly caps (non RoHs) which, I guess, will not be sold in the EU and elsewhere soon.
http://www.solen.ca/
click “On Sale”
When the new caps arrive, I'll borrow the meter again. For the 72uf locations, I ordered 68ufs, which I'll measure--and add ufs to, as necessary. The 24uf location can also be tweaked.
I feel better now that these large uf value caps are out of the way...they're a big expense in this restoration. For the smaller 4uf/4uf/6uf locations, I ordered a variety of uf values that can be combined, with or without the Eries, for various +/- 4 and 6 uf values. Thus, we should be able to tweak the uf values at the midrange and treble locations to exactly how we want them, while considering the DCR of the drivers.........look at poor blackie 2, with its high 5.0 DCR tweeter and ultrahigh 13.42 uf cap in the 6uf treble location.
Sba
I borrowed the meter from a friend of a friend. I was told that it's primarily an in-circuit ESR meter, but will also test for capacitance values (also in-circuit, according to the accompanying manual). ( I think the meter discharges the caps first.) But, after testing two caps in-circuit, I noticed that while the ESR part was working okay , the cap value readings were running amok into the hundreds of ufs.
So...I snipped a cap, pulled it out, attached the alligator clips (isolated, out-of-circuit, no hands touching), and pressed the test button. The results were good. It became a cap "demolition" project, where each cap was snipped and measured. After I had finished, I calibrated the meter and measured all the caps again. The results were almost identical.
I measured all the bundled caps together and then individually. The sum of the individuals equaled the bundled total; however, I thought it unnecessary to list individually those few bundled 72uf electros and Erie m312 polyesters.
On the other hand, the bundled Erie A304 and A316 were listed individually because, if they are in fact oil-impregnated metallized film caps (and somewhat stable), I would like to re-use them---one at each 4uf and 6uf treble location on all four crossovers (piggybacking something else to the Eries where necessary).
By any chance, do you know what that "A" stands for on the Erie caps? With the Erie M312's, I'm pretty sure that the "M" stands for Polyester.
*****************
I just made an impulse purchase of Solen caps!! I was going over my calculations again and realized that I had only budgeted for four 72ufs, instead of the required eight. After more price checking, I found Solen caps on sale for half the normal price at the Solen Canada web site. The catch is...it's existing stock of non environmentally friendly caps (non RoHs) which, I guess, will not be sold in the EU and elsewhere soon.
http://www.solen.ca/
click “On Sale”
When the new caps arrive, I'll borrow the meter again. For the 72uf locations, I ordered 68ufs, which I'll measure--and add ufs to, as necessary. The 24uf location can also be tweaked.
I feel better now that these large uf value caps are out of the way...they're a big expense in this restoration. For the smaller 4uf/4uf/6uf locations, I ordered a variety of uf values that can be combined, with or without the Eries, for various +/- 4 and 6 uf values. Thus, we should be able to tweak the uf values at the midrange and treble locations to exactly how we want them, while considering the DCR of the drivers.........look at poor blackie 2, with its high 5.0 DCR tweeter and ultrahigh 13.42 uf cap in the 6uf treble location.
Sba
Hello again!
Very busy period, still I am reading everything and hope to be able to post some more soon. I made some photos, maybe this weekend I will be able to upload them. So far all the caps on my crossovers look very good, but then again, you never know. I am really missing the gear I need to do all the measurements you guys do, so for the moment I will try to read and extract the useful info.
And one more thing, I am now shure I need two midranges. Mine sound very good, nothing bad comes out, even at higher input (50-60W). But they look like the glue is al over the place and I am shure that this is not the way they suposed to be. Once you will see the pics everything will make sense.
So if anybody sees two very good midrange speakers, including on Ebay, please give me a sign here. I am cheking this thread daily so I can't miss it.
One question for you 66 users. What amps do you use? What sources and how whould you describe the result? I have a Pioneer Spec 4 on it's way (tomorow should be home) and I can't wait to see how will they match togheter.
More to be said, soon.
Cheers!
PS: Hope my English is better this time. It's a long time since I have stoped learning it.
Very busy period, still I am reading everything and hope to be able to post some more soon. I made some photos, maybe this weekend I will be able to upload them. So far all the caps on my crossovers look very good, but then again, you never know. I am really missing the gear I need to do all the measurements you guys do, so for the moment I will try to read and extract the useful info.
And one more thing, I am now shure I need two midranges. Mine sound very good, nothing bad comes out, even at higher input (50-60W). But they look like the glue is al over the place and I am shure that this is not the way they suposed to be. Once you will see the pics everything will make sense.
So if anybody sees two very good midrange speakers, including on Ebay, please give me a sign here. I am cheking this thread daily so I can't miss it.
One question for you 66 users. What amps do you use? What sources and how whould you describe the result? I have a Pioneer Spec 4 on it's way (tomorow should be home) and I can't wait to see how will they match togheter.
More to be said, soon.
Cheers!
PS: Hope my English is better this time. It's a long time since I have stoped learning it.
Too soon with Solen caps !
Hi sba,
well you've jumped the gun and ordered caps before I got to that, but since I'm going to Post my recommendations later for the other guys you will find out eventually, this I may as well say now :-
68uF + 4uF is not the best audible way to achieve 72uF.
I don't know how much it will matter for those 72uF caps in parallel with the woofers, but with two widely spaced cap values a double resonance is set up. This is not as smearing of details and dynamics as the Dielectric Absorption of electrolytic caps cause, but better can be achieved by parallelling equal or near-to values.
For 72uF I would parallel 39uF + 33uF.
For Series connected caps, such as the 24uF to the MD500, and the 4uF and 6uF to the HF2000, it is audibly more critical to pair carefully if one has to use parallels, because the differences in the Pulse Rise Times between the caps cause signal to in effect pass through one cap of the pair faster than through the other, and this audibly changes the timbre {tone character of an instrument or voice}.
Larger value caps have slower pulse rise times than smaller value caps, as do caps of different Dielectrics, and even if use the same type of dielectric but different internal construction, or even different Voltage rating {in some cases} pulse rise times can be different.
Yes, I remember that Post where you wrote some of what you had read about combining various types and values of caps, and I only commented on that briefly then.
Basically that can work in Power Supplies when one needs to filter out wide-band noise, but to apply optimally one has to measure the results to ensure there has not been created one or more Resonant modes which couple into the circuit.
It is not a simple subject and I didn't want to type hundreds of words to explain it all, nor will I now, but ... for people who like to experiment, anything can and will be tried, and some experimenters chance upon sounds they like, and other experimenters don't, but simply keep on buying components to try every idea some-one has posted about a path to Audio Nirvana, but without understanding what they are doing.
I'm sorry that I don't have sufficient time available to address quickly or always comprehensively every point someone raises in this Thread, but as it seemed that every-one was not in a hurry I would have got to cap selection after getting through the relevant interim matters.
I don't know what you've ordered for 24uF, but I hope it is simply a 24uF single cap, or two 12uF caps.
Similarly, for the 4uF I would use a single 4uF or a single 3.9uF {which is only -2% difference}.
Some Brands have a single 6uF cap, or a near to such as 6.2uF, or a close values way of pairing.
I will be listing some of these when I list the reasonable value lower priced brands.
Also, for audilble consistency, presuming one has available a well made cap, one should use the same Brand and type and model {including voltage if possible} in all positions in at least each Filter arm of the cross-over, and maybe in the entire cross-over.
Thus I would never advise paralleling different brands or dielectric types, but any-one is free to try that and listen - who knows, one may chance on something one likes for the music types one listens to mostly.
Similarly the physical sizes, 100 Volt size is adequate if well made, and one does not need the larger 250 volt nor 400 volt sizes in cross-overs for domestic use loudspeakers that will not accept such large voltages, such as these old Celestions.
High voltage caps are only of audible benefit when there are large voltage stresses.
More important is how well the cap is manufactured, and you have already read something about this - I will explain more when time is available when I am recommending the alternate brands.
Some caps are manufactured to be Signal caps in amplifiers where there is small signal AC and large DC voltages present simultaneously, and this does not occur in loudspeaker cross-overs.
Well, if you have ordered I suppose you can't cancel now.
What are the cap values in your Dahlquist DQM-9 ?
You may be able to use some of the Solens more effectively there.
Hi sba,
well you've jumped the gun and ordered caps before I got to that, but since I'm going to Post my recommendations later for the other guys you will find out eventually, this I may as well say now :-
68uF + 4uF is not the best audible way to achieve 72uF.
I don't know how much it will matter for those 72uF caps in parallel with the woofers, but with two widely spaced cap values a double resonance is set up. This is not as smearing of details and dynamics as the Dielectric Absorption of electrolytic caps cause, but better can be achieved by parallelling equal or near-to values.
For 72uF I would parallel 39uF + 33uF.
For Series connected caps, such as the 24uF to the MD500, and the 4uF and 6uF to the HF2000, it is audibly more critical to pair carefully if one has to use parallels, because the differences in the Pulse Rise Times between the caps cause signal to in effect pass through one cap of the pair faster than through the other, and this audibly changes the timbre {tone character of an instrument or voice}.
Larger value caps have slower pulse rise times than smaller value caps, as do caps of different Dielectrics, and even if use the same type of dielectric but different internal construction, or even different Voltage rating {in some cases} pulse rise times can be different.
Yes, I remember that Post where you wrote some of what you had read about combining various types and values of caps, and I only commented on that briefly then.
Basically that can work in Power Supplies when one needs to filter out wide-band noise, but to apply optimally one has to measure the results to ensure there has not been created one or more Resonant modes which couple into the circuit.
It is not a simple subject and I didn't want to type hundreds of words to explain it all, nor will I now, but ... for people who like to experiment, anything can and will be tried, and some experimenters chance upon sounds they like, and other experimenters don't, but simply keep on buying components to try every idea some-one has posted about a path to Audio Nirvana, but without understanding what they are doing.
I'm sorry that I don't have sufficient time available to address quickly or always comprehensively every point someone raises in this Thread, but as it seemed that every-one was not in a hurry I would have got to cap selection after getting through the relevant interim matters.
I don't know what you've ordered for 24uF, but I hope it is simply a 24uF single cap, or two 12uF caps.
Similarly, for the 4uF I would use a single 4uF or a single 3.9uF {which is only -2% difference}.
Some Brands have a single 6uF cap, or a near to such as 6.2uF, or a close values way of pairing.
I will be listing some of these when I list the reasonable value lower priced brands.
Also, for audilble consistency, presuming one has available a well made cap, one should use the same Brand and type and model {including voltage if possible} in all positions in at least each Filter arm of the cross-over, and maybe in the entire cross-over.
Thus I would never advise paralleling different brands or dielectric types, but any-one is free to try that and listen - who knows, one may chance on something one likes for the music types one listens to mostly.
Similarly the physical sizes, 100 Volt size is adequate if well made, and one does not need the larger 250 volt nor 400 volt sizes in cross-overs for domestic use loudspeakers that will not accept such large voltages, such as these old Celestions.
High voltage caps are only of audible benefit when there are large voltage stresses.
More important is how well the cap is manufactured, and you have already read something about this - I will explain more when time is available when I am recommending the alternate brands.
Some caps are manufactured to be Signal caps in amplifiers where there is small signal AC and large DC voltages present simultaneously, and this does not occur in loudspeaker cross-overs.
Well, if you have ordered I suppose you can't cancel now.
What are the cap values in your Dahlquist DQM-9 ?
You may be able to use some of the Solens more effectively there.
Guys... Some good news and some very bad news...
The good news is that the Pioneer Spec 4 arrived and it sounded....way better than what I have tryed before on my 66's. It was something that made me understand that they can do much better...
The bad news is that the Spec 4 had a faulty left channel... And I have tested it with to other (test) speakers to see if it's ok to put the 66's on it... Nothing hapened then, everything ok!
I listened for about 30 min, then went into the kitchen for a few minutes. Sudenly I heard a loud noise. That was the left 66, and the amp that was probably running DC on that channel (I supose, tomorow I will check more, right now I don't even want to see it). The amp had absolutely no signal when that happened and the amp had 4 units up from the 0 position on the level knobs... The player was in standby. So, in other words, I am looking now for one bass speaker, or maybe a pair if someone has them ready to ship... I have never had an experience like this, I can't whait to see why that hapened!
Al the bad thing bring good things. I will now begin working on my 66's and also on other stuff that I ignored in the past weeks. Things that are allready planned, like doing some work on my audition room.
Pictures tomorow..
The good news is that the Pioneer Spec 4 arrived and it sounded....way better than what I have tryed before on my 66's. It was something that made me understand that they can do much better...
The bad news is that the Spec 4 had a faulty left channel... And I have tested it with to other (test) speakers to see if it's ok to put the 66's on it... Nothing hapened then, everything ok!
I listened for about 30 min, then went into the kitchen for a few minutes. Sudenly I heard a loud noise. That was the left 66, and the amp that was probably running DC on that channel (I supose, tomorow I will check more, right now I don't even want to see it). The amp had absolutely no signal when that happened and the amp had 4 units up from the 0 position on the level knobs... The player was in standby. So, in other words, I am looking now for one bass speaker, or maybe a pair if someone has them ready to ship... I have never had an experience like this, I can't whait to see why that hapened!
Al the bad thing bring good things. I will now begin working on my 66's and also on other stuff that I ignored in the past weeks. Things that are allready planned, like doing some work on my audition room.
Pictures tomorow..
be wary of used amplifiers !
Hi ReLLaXX,
I am saddened to read of the mishap, and the damage the Pioneer amp seems to have done to one of your 66s.
Did you buy that amp without trying it first ?
Really it is not a good idea to buy amplifiers that are not new sealed-in-carton unless trying them before purchase, connected to loudspeakers.
It does not matter whether the Brand name is reputable or not, because one never knows what the previous owner did with the amp.
You could try to have the amp repaired , but ONLY have this done by a authorized Pioneer repair shop, as they will have the Schematic Diagram for the circuit.
It is safer to buy amplifiers new.
I do not know what brands of amplifiers are available in your country, though a new model Rotel or NAD amplifier will work fine with the Celestion 66s.
The amp's Power you will need will depend on how large or small your listening room is, and on how loud you want to play the music, but old speakers like the 66s will not play safely as loud as similar good quality modern speakers of the same size.
Yes, do post photos of your 66s, and in particular do post a close-up photo of the midrange drivers so that we can clearly see the glue that you wrote about.
Hi ReLLaXX,
I am saddened to read of the mishap, and the damage the Pioneer amp seems to have done to one of your 66s.
Did you buy that amp without trying it first ?
Really it is not a good idea to buy amplifiers that are not new sealed-in-carton unless trying them before purchase, connected to loudspeakers.
It does not matter whether the Brand name is reputable or not, because one never knows what the previous owner did with the amp.
You could try to have the amp repaired , but ONLY have this done by a authorized Pioneer repair shop, as they will have the Schematic Diagram for the circuit.
It is safer to buy amplifiers new.
I do not know what brands of amplifiers are available in your country, though a new model Rotel or NAD amplifier will work fine with the Celestion 66s.
The amp's Power you will need will depend on how large or small your listening room is, and on how loud you want to play the music, but old speakers like the 66s will not play safely as loud as similar good quality modern speakers of the same size.
Yes, do post photos of your 66s, and in particular do post a close-up photo of the midrange drivers so that we can clearly see the glue that you wrote about.
Hi Alan,
For your much appreciated help, and quick replies, I want to extend a very warm thank you.
I was a bit overwhelmed by needing many caps for many speakers. So, when I came across the sale with limited quantities, I jumped the gun. Having looked around at prices, I knew that I wouldn't find good poly caps for much less.
For the 72uf location, I had the option to order two 36ufs but, instead, bought the larger cap for a couple of reasons. If the 36ufs turned out to measure high by several ufs, we would be exceeding our 72uf target. The other consideration was with mounting; I felt that it would be easier to handle and install just two large caps on each board--versus four 36s. Hopefully...if the large caps measure a bit high, we can just use them solo.
Had I known that there was a cap “balance” issue involved, I would have re-considered. My cap installation reading only covered simple things--e.g., series vs parallel connection; the effective voltage of mixed-voltage bundled caps = that of the lowest voltage cap, etc.
And my observation of the Celestion boards told me that it was okay to bundle caps (two 30s & one 12 at the 72 location + the treble cap mixtures); to mix brands (four different ones); to mix voltages (25v/50v/150v); and to mix dielectrics ( electros/ polyesters/ metallized film). Well...now I know that some of these conditions might not provide optimal results.
My intention with piggybacking the Erie caps was simply to mix their good qualities with the inherent good qualities of poly caps. But I'm now ready to drop that plan of bundling mixed dielectrics.
So, then...Would you extend the "use the same dielectric" recommendation to the entire treble portion of the crossover? For example, four of the Eries have values that are near 4uf ( 3.9 / 3.9 / 4.0 / 4.2 ). Would you recommend using them solo in the 4uf location, while placing new polys in the 6uf location? Or just use polys throughout?
Compared to the large-value uf caps, the purchase of assorted 3.9 and smaller caps was inexpensive ( 1.00 or less per cap); and I'm prepared to buy different replacements if necessary.
The Solen caps are being sent by snail-mail from Canada. When they arrive in a few weeks, I'll borrow the meter and measure what we have to work with.
Thanks again
Scott / sba
For your much appreciated help, and quick replies, I want to extend a very warm thank you.
I was a bit overwhelmed by needing many caps for many speakers. So, when I came across the sale with limited quantities, I jumped the gun. Having looked around at prices, I knew that I wouldn't find good poly caps for much less.
For the 72uf location, I had the option to order two 36ufs but, instead, bought the larger cap for a couple of reasons. If the 36ufs turned out to measure high by several ufs, we would be exceeding our 72uf target. The other consideration was with mounting; I felt that it would be easier to handle and install just two large caps on each board--versus four 36s. Hopefully...if the large caps measure a bit high, we can just use them solo.
Had I known that there was a cap “balance” issue involved, I would have re-considered. My cap installation reading only covered simple things--e.g., series vs parallel connection; the effective voltage of mixed-voltage bundled caps = that of the lowest voltage cap, etc.
And my observation of the Celestion boards told me that it was okay to bundle caps (two 30s & one 12 at the 72 location + the treble cap mixtures); to mix brands (four different ones); to mix voltages (25v/50v/150v); and to mix dielectrics ( electros/ polyesters/ metallized film). Well...now I know that some of these conditions might not provide optimal results.
My intention with piggybacking the Erie caps was simply to mix their good qualities with the inherent good qualities of poly caps. But I'm now ready to drop that plan of bundling mixed dielectrics.
So, then...Would you extend the "use the same dielectric" recommendation to the entire treble portion of the crossover? For example, four of the Eries have values that are near 4uf ( 3.9 / 3.9 / 4.0 / 4.2 ). Would you recommend using them solo in the 4uf location, while placing new polys in the 6uf location? Or just use polys throughout?
Compared to the large-value uf caps, the purchase of assorted 3.9 and smaller caps was inexpensive ( 1.00 or less per cap); and I'm prepared to buy different replacements if necessary.
The Solen caps are being sent by snail-mail from Canada. When they arrive in a few weeks, I'll borrow the meter and measure what we have to work with.
Thanks again
Scott / sba
Alan,
Thank you for the good advice... Let's say I am not really a begginer in sound and music... Ofcourse I have tryed the amp first, before purchase and after, before using it on my 66's. I was talking about this in my last post. Anyway, I have the schematic diagram for Pioneer's Spec 4 on it's way so it's no need to take it to a authorized repair shop. I don't need to pay for the sign above the entry door. This is the DIY Audio forum, right? Now really, someone with enough experience will look over it, from A to Z. It's a very old amp, I wanted it especially.
I can buy ANYTHING in Romania, anything that is distributed anywhere in the world. There are a lot of brands to choose from. But that is not the point. I wanted to try Pioneer's Spec 4 for a personal curiosity. I am a fan of vintage audio (and "vintage" cars also ). Sometimes I want something and search it until I cand get it. If I like it it stays, if not... it goes. I've worked in Pro Audio (sound systems in/outdoor, DJ-ing, radio broadcasting) for more than 8 years and I know what LOUD means. There are three years now since I've turned to competition car-audio instals and also with good results. I really now what LOUD means... like 150 db+ on music LOUD. I do not listen to that kind of levels, I do not need that at home. Because I also know what sound quality means... I bought the Celestions for music, not for high volume... Pioneer's Spec 4 is a good amp, with lots of headroom, ideal for speakers that don't have a great SPL.... Like the 66's. It's a dual mono design and the power is more than enough for anything, but especially for giving a great amount of dynamics and detail at low levels... In a few words, I liked the Spec 4 on the 66's, a lot. And I did listen to a few others before it, in the last 10 years. I will try some more matches on the 66's, but with the Spec 4 I really thing I am on to something interesting.
I could by a new-in the box- amp for the same money and if not, for even more money. But it has to be more than an amp for me. If that was not the way, I would probably use some now shiny speakers, right of the shelf, not my old 66's. Let's call it The Nostalgic Factor. Even if I'm younger than my Celestions.
My listening room has about 25 square meters. Celestion Studio Monitor is a great near/medium distance (field) speaker, and if the room is not prepaired enough their focus and staging capacity is reduced. So even if it's a medium/large sized room, I can't listen from a greater distance (another reason for needing more power to drive them). I will be testing a Quad 22 combo next weekend, so there will be 2 x 15W available. If the sound is RIGHT, that's more than enough. When I've tested the Spec 4 I did not see the indicator over 1 W... There where 3 or 4 times when I peaked an amplifier to about 50W on the Celestions, and that was just for measuring pourposes, with an RTA, to get some idea about the treatment my room needs.
SO, in a nutshell, the mistake with the Spec 4 is mine, I will live with it. And so the Celestions because in a few days the replacement bass speaker will be here, ready to work. Hope it is in good shape... I'l keep my fingers crossed. I am still looking for replacement speakers! You never know...
I can't post pictures, I don't know why.... I will try again tomorow.
Thank you for the good advice... Let's say I am not really a begginer in sound and music... Ofcourse I have tryed the amp first, before purchase and after, before using it on my 66's. I was talking about this in my last post. Anyway, I have the schematic diagram for Pioneer's Spec 4 on it's way so it's no need to take it to a authorized repair shop. I don't need to pay for the sign above the entry door.
This is the DIY Audio forum, right? Now really, someone with enough experience will look over it, from A to Z. It's a very old amp, I wanted it especially. I can buy ANYTHING in Romania, anything that is distributed anywhere in the world. There are a lot of brands to choose from. But that is not the point. I wanted to try Pioneer's Spec 4 for a personal curiosity. I am a fan of vintage audio (and "vintage" cars also
). Sometimes I want something and search it until I cand get it. If I like it it stays, if not... it goes. I've worked in Pro Audio (sound systems in/outdoor, DJ-ing, radio broadcasting) for more than 8 years and I know what LOUD means. There are three years now since I've turned to competition car-audio instals and also with good results. I really now what LOUD means... like 150 db+ on music LOUD. I do not listen to that kind of levels, I do not need that at home. Because I also know what sound quality means... I bought the Celestions for music, not for high volume... Pioneer's Spec 4 is a good amp, with lots of headroom, ideal for speakers that don't have a great SPL.... Like the 66's. It's a dual mono design and the power is more than enough for anything, but especially for giving a great amount of dynamics and detail at low levels... In a few words, I liked the Spec 4 on the 66's, a lot. And I did listen to a few others before it, in the last 10 years. I will try some more matches on the 66's, but with the Spec 4 I really thing I am on to something interesting. I could by a new-in the box- amp for the same money and if not, for even more money. But it has to be more than an amp for me. If that was not the way, I would probably use some now shiny speakers, right of the shelf, not my old 66's. Let's call it The Nostalgic Factor. Even if I'm younger than my Celestions.
My listening room has about 25 square meters. Celestion Studio Monitor is a great near/medium distance (field) speaker, and if the room is not prepaired enough their focus and staging capacity is reduced. So even if it's a medium/large sized room, I can't listen from a greater distance (another reason for needing more power to drive them). I will be testing a Quad 22 combo next weekend, so there will be 2 x 15W available. If the sound is RIGHT, that's more than enough. When I've tested the Spec 4 I did not see the indicator over 1 W... There where 3 or 4 times when I peaked an amplifier to about 50W on the Celestions, and that was just for measuring pourposes, with an RTA, to get some idea about the treatment my room needs.
SO, in a nutshell, the mistake with the Spec 4 is mine, I will live with it. And so the Celestions because in a few days the replacement bass speaker will be here, ready to work. Hope it is in good shape... I'l keep my fingers crossed. I am still looking for replacement speakers! You never know...
I can't post pictures, I don't know why.... I will try again tomorow.
Alan,
I called Solen (Canada) this morning to try to modify my order. No luck...it was shipped on Friday. However, I was able to speak to a Solen engineer about my dilemma. He said that if I was using "older-style" caps or "lesser-quality" caps, then cap balancing would be an issue....but, since Solen caps are "fast" and of high quality, there is no problem at all in mixing the ufs any which way, or in mixing voltages. I feel a little better.
************************
Dust Caps on the Woofers:
I just examined the markings on all the woofers. All the original 66 woofers have baskets marked T 1600, and paper cones marked 938. The replacement woofers from last summer, with their larger dust caps, are marked T 2619, while their paper cones are still marked 938.
sba
I called Solen (Canada) this morning to try to modify my order. No luck...it was shipped on Friday. However, I was able to speak to a Solen engineer about my dilemma. He said that if I was using "older-style" caps or "lesser-quality" caps, then cap balancing would be an issue....but, since Solen caps are "fast" and of high quality, there is no problem at all in mixing the ufs any which way, or in mixing voltages. I feel a little better.
************************
Dust Caps on the Woofers:
I just examined the markings on all the woofers. All the original 66 woofers have baskets marked T 1600, and paper cones marked 938. The replacement woofers from last summer, with their larger dust caps, are marked T 2619, while their paper cones are still marked 938.
sba
better to listen to experimental results than to trust manufacturers !
Sorry to be cynical sba, but that is fully what I expect a Solen engineer to say, or any audio component engineer to say about his current product.
The best that can happen with a very Fast cap. is that the pulse rise times will be such that for the larger slower cap it will rise fast enough to exceed the treble extension of a tweeter, and thus one may not hear that the smaller faster cap is faster rise time, but I think I would audibly detect something it would dcause as a by-product of being in a parallel resonant circuit.
For the 68uF + 4uF, perhaps any deleterious effect can be reduced with a separate low ohms series ESR simulating resistor connected to each cap inside the loop before paralleling.
Don't be surprized if you prefer the sound with only 68uF in circuit, instead of a resonant loop attempting 72uF.
Of course the resonances in the cones of the woofers may be to sufficient degree in the midrange area just where the cross-over filter begins its roll-off to mask, or confuse, the audibility in this case.
The MD500 is the best driver in the 66s, thus really it deserves the best audio application of capacitor combination.
You were concerned about audible differences when deciding a brand, well if well manufactured there will likely be greater audible difference between a 24uF and a 20uF + 4uF {for example} than there will be between two well manufactured MKP caps of different brands of the same price/quality level.
Post a list of the caps you have bought - values and voltages - and I'll try to think of something.
Did you buy any for your Dahlquists ?
More about caps, and ESR simulating resistors when time is available,
and I'll post a thought about the cones and dust caps then also I hope.
Sorry to be cynical sba, but that is fully what I expect a Solen engineer to say, or any audio component engineer to say about his current product.
The best that can happen with a very Fast cap. is that the pulse rise times will be such that for the larger slower cap it will rise fast enough to exceed the treble extension of a tweeter, and thus one may not hear that the smaller faster cap is faster rise time, but I think I would audibly detect something it would dcause as a by-product of being in a parallel resonant circuit.
For the 68uF + 4uF, perhaps any deleterious effect can be reduced with a separate low ohms series ESR simulating resistor connected to each cap inside the loop before paralleling.
Don't be surprized if you prefer the sound with only 68uF in circuit, instead of a resonant loop attempting 72uF.
Of course the resonances in the cones of the woofers may be to sufficient degree in the midrange area just where the cross-over filter begins its roll-off to mask, or confuse, the audibility in this case.
The MD500 is the best driver in the 66s, thus really it deserves the best audio application of capacitor combination.
You were concerned about audible differences when deciding a brand, well if well manufactured there will likely be greater audible difference between a 24uF and a 20uF + 4uF {for example} than there will be between two well manufactured MKP caps of different brands of the same price/quality level.
Post a list of the caps you have bought - values and voltages - and I'll try to think of something.
Did you buy any for your Dahlquists ?
More about caps, and ESR simulating resistors when time is available,
and I'll post a thought about the cones and dust caps then also I hope.
amplifiers ; replacement 12" Celestion driver
Hi ReLLaXX,
It is good that you were able to obtain the Schematic for your Pioneer amp, and that you know some-one who can check the amp reliably for you.
I agree with you about DIY, and I think DIY is good when one is able to do it or get good advice about how to do it.
I also agree with using Vintage audio components that one likes, and I hope you can get that amp working well.
You have a large listening room, but the 66s should be fine in that size.
Do not be surprised if the Quad 22 does not drive the 66 well in a large room, as 15 watts is not much for when loud sections of music come along.
As the Quad 22 is a Valve {tube} amp, it will have a higher Output Impedance than your Pioneer and than most solid state amps.
This higher output impedance will interact with the in-box bass tuning resonant frequencies caused by the Passive Radiator in the Celestion 66, and cause the speakers to sound quite different in the bass than they would with the Pioneer and most modern solid state amps.
But you might like this bass effect - Post and tell us what you find with the bass response after you have tried the Quad 22.
For a new amp, I think you might like the NAD C372 driving the 66s in your large room, but a good vintage amp is still OK.
As you say, the amp has to be the right one for the user !
It is good that a wide variety of audio equipment is available to Romania - I did not know this because I have not investigated since the liberation of Eastern European Nations various numbers of years ago.
Where did you find a replacement driver for the 66 so soon ?
Easy, or simply lucky ?
Hi ReLLaXX,
It is good that you were able to obtain the Schematic for your Pioneer amp, and that you know some-one who can check the amp reliably for you.
I agree with you about DIY, and I think DIY is good when one is able to do it or get good advice about how to do it.
I also agree with using Vintage audio components that one likes, and I hope you can get that amp working well.
You have a large listening room, but the 66s should be fine in that size.
Do not be surprised if the Quad 22 does not drive the 66 well in a large room, as 15 watts is not much for when loud sections of music come along.
As the Quad 22 is a Valve {tube} amp, it will have a higher Output Impedance than your Pioneer and than most solid state amps.
This higher output impedance will interact with the in-box bass tuning resonant frequencies caused by the Passive Radiator in the Celestion 66, and cause the speakers to sound quite different in the bass than they would with the Pioneer and most modern solid state amps.
But you might like this bass effect - Post and tell us what you find with the bass response after you have tried the Quad 22.
For a new amp, I think you might like the NAD C372 driving the 66s in your large room, but a good vintage amp is still OK.
As you say, the amp has to be the right one for the user !
It is good that a wide variety of audio equipment is available to Romania - I did not know this because I have not investigated since the liberation of Eastern European Nations various numbers of years ago.
Where did you find a replacement driver for the 66 so soon ?
Easy, or simply lucky ?
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