| I'm sorry, but the amp needs a zobel - Click HERE for Original Thread |
| carlosfm |
Long time ago I tested zobels, because I had bad results with direct output and my Kimber 4TC speaker cables.
The amp was very picky with cables and speakers.
The best result I had was two 0.47 ohm/3w carbon resitors in series with the output.
I tested a resistor and cap to ground, with several values, and it didn't cure the problem.
What I didn't test was both.
I tested some days ago, several values, and I like it.
This time I'm not going into details, or this thread will degenerate into a big discussion.
Try it, listen and tell us what you think.:cool:
Note: by speaker terminals I mean on the amp.
This is what I have now, here it is: |
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| Mad_K |
| I prefer it without the 0,47R resistors, but the zobel is mandatory. It didn't take much listening to reveal that the chip needs a zobel at the output. Place the zobel as close to the chip as possible ;) |
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| carlosfm |
| quote: | Originally posted by Mad_K
I prefer it without the 0,47R resistors, but the zobel is mandatory. |
I can't detect any side effect with the series resistors, at least with the cables and speakers I tested.
| quote: | Originally posted by Mad_K
Place the zobel as close to the chip as possible ;) |
I said that the zobel can be on the amp's speaker terminals because it's easier for people to test it.
Ideally it should be near the chip, but on some implementations that may not be practical.
I will put it definitively near the chip.;)
Thanks for your feedback.:angel: |
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| Sheldon |
Or use a LP filter, ala Joe Rasmussen, on the input?
Sheldon |
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| carlosfm |
| No, Sheldon, that's different, nothing to do with this... |
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| Sheldon |
| quote: | Originally posted by carlosfm
No, Sheldon, that's different, nothing to do with this... |
Ok, guess this is where partial knowledge is dangerous. I thought the function of the Zobel was to prevent instability of the amp due to high frequency (above audio) oscillation. If you prevent those frequencies from entering the stream, don't you circumvent the problem? Or have I got that all wrong?
thanks,
Sheldon |
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| sam9 |
| I wonder if the .47 resistors are inductive. Maybe you have inadvertently added an output inductor as well. |
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| carlosfm |
| quote: | Originally posted by sam9
I wonder if the .47 resistors are inductive. Maybe you have inadvertently added an output inductor as well. |
That's why I use carbon and not bobinated resistors.
You shouldn't use bobinated resistors on the output.
For inductance and other nasties, we have the speaker cables, speaker crossovers...
The zobel makes the amp more immune to these nasties.
Sheldon, this has to be done at the output. |
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| sam9 |
| Sigh! I should read more carefully. |
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| analog_sa |
| quote: | | I'm sorry, but the amp needs a zobel |
Maybe, but which chip? The 1875 seems to really need it; the 3875 might need it with some combinations of speakers and cables.
| quote: | | That's why I use carbon |
These carbon resistors have such a pronounced 'voice' of their own that it's absolutely impossible to distinguish the contribution of the zobel and the rose tint of the carbons. Great if you like warm and cushy sound. |
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| carlosfm |
| quote: | Originally posted by analog_sa
Maybe, but which chip? The 1875 seems to really need it; the 3875 might need it with some combinations of speakers and cables. |
The LM1875 benefits, I tested it on one I have.
The LM3875 should, because I tested also with the LM3886, my power amp on my main system.
| quote: | Originally posted by analog_sa
These carbon resistors have such a pronounced 'voice' of their own that it's absolutely impossible to distinguish the contribution of the zobel and the rose tint of the carbons. Great if you like warm and cushy sound. |
This is a starting point.
I used what I found easily, no film resistors around here at these wattages.:bawling:
Even then, I prefer the carbon resistors there, because Kimber cables are mid/high capacitance, the amp plays better with the series resistors.
Use them as in any op-amp's output, to isolate the chip from capacitance.
There are several issues here.
I'm posting what works best for me.
People are free to try and, if needed, adapt to their reality.
Start with this, it's better than direct output.:cool: |
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| aHobbit |
| quote: | Originally posted by carlosfm
Long time ago I tested zobels, because I had bad results with direct output and my Kimber 4TC speaker cables.
The amp was very picky with cables and speakers.
The best result I had was two 0.47 ohm/3w carbon resitors in series with the output.
I tested a resistor and cap to ground, with several values, and it didn't cure the problem.
What I didn't test was both.
I tested some days ago, several values, and I like it.
This time I'm not going into details, or this thread will degenerate into a big discussion.
Try it, listen and tell us what you think.:cool:
Note: by speaker terminals I mean on the amp.
This is what I have now, here it is: |
I have this in my original NIGC, together with a Zobel network, as well as with JoeRas suggestion of speaker return to the rail caps ground meeting point. No 0.22 ohm at the output though.
The sound is very nice and way above my commercial AV receiver amp.
I then removed the Zobel network first afterwards. I did not notice any change in the sound. Still awed by how it delivers crisp and balanced music.
Then I finally removed the Snubber circuit (the 2.7R and 0.1 cap), No change in the sound also. So I stayed in this configuration.
IMHO, these circuits (Zobel and Snubber) is only needed to protect the amp and speaker from too many variables (speaker and cable and perhaps what environment the amplifier is installed).
Since it looks like my setup is not introducing the nasty signals, and I am not likely to change setup, I decided that I have no need for it, though I provided speaker protector.
IF I will change my cable or speaker later, then I have to reintroduce again these circuits just to be safe, and remove it if I found again it is not necessary on the change.
Thank you guys. It is only now that I enjoy a truly high end music at a little cost. |
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| thomas997 |
What effect would be produced by using a lower value capacitor?
Around 0.05uF instead?
thanks |
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| carlosfm |
| quote: | Originally posted by thomas997
Around 0.05uF instead?
thanks |
You can parallel them to make around 0.1uf. |
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| mrskinny |
| Tried this a couple of nights ago. I am using NI OPA549 chips now,as I broke my LM1875 amp again (insert cursing here). Looked at the data sheet,which shows a zobel,but no resistors on the output. No parts values given,but I found another TI data sheet "A Complete Audio Amplifier" which shows a 1K resistor + a .22uf capacitor.Surprisingly enough I had these parts,so on they went.Sounded murky at first (new parts),but after an hour or so cleared up.These smoothened the sound out quite a bit- got rid of the bit of hardness to the sound that I didn't like with these chips. Clearer too. Thanks for the suggestion Carlos! BTW, the regulated supplies worked wonders with these chips. |
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| carlmart |
| quote: | Originally posted by mrskinny
No parts values given,but I found another TI data sheet "A Complete Audio Amplifier" which shows a 1K resistor + a .22uf capacitor.Surprisingly enough I had these parts,so on they went.Sounded murky at first (new parts),but after an hour or so cleared up.These smoothened the sound out quite a bit- got rid of the bit of hardness to the sound that I didn't like with these chips. Clearer too. |
Are you sure of the resistor value? Most zobel resistors I have seen are just a few ohms, usually 10 in series with .1uF. The resistor has to be 1W type. Why don't you try those values and see what happen? The zobel is a filter tuned to a cut above a certrain frequency, so what you used is working, but perhaps not as a zobel should.
Carlos |
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| carlosfm |
You did well in using the recommended values for those chips.
But... 1k?:confused:
I think you mean 1 ohm?
The values I suggested are for National chips, and on these, depending on the cables and speakers used, the improvement can be amazing.
Oh... regulated PSU?
Of course...:cool: |
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| thomas997 |
| quote: | Originally posted by carlosfm
You can parallel them to make around 0.1uf. |
Yeah I guess I will, but it would mean I have to buy more caps..
I thought I set a limit on this project :p |
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| mrskinny |
| I thought the 1K value seemed high too. I looked at the data sheets for a few other chips, which show low value resistors- 1R, 2.2R,etc. Looked at the sheet that I got this from again, but it does say 1K. I have (hopefully) included this below. It could be a misprint, but this was shown twice the same way on the datasheet. |
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| runebivrin |
Not to be picky, but a more useful format would be better. .CLP isn't something I know how to read.
Rune |
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| GregGC |
| quote: | Originally posted by mrskinny
I thought the 1K value seemed high too. I looked at the data sheets for a few other chips, which show low value resistors- 1R, 2.2R,etc. Looked at the sheet that I got this from again, but it does say 1K. I have (hopefully) included this below. It could be a misprint, but this was shown twice the same way on the datasheet. |
It's a misprint in the datasheet. It HAS to be 1R. It's surprising how many errors you'd find in the datasheets.
/Greg |
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| mrskinny |
| Sorry about the odd format,but it was the only way that I could get the diagram off the data sheet.I've cursed that damn Acrobat Reader I don't know how many times! You have to unzip the folder,then open it using the clipboard viewer (in Windows,don't know if it will work with a Mac).I will be going to the parts place later this week,so I will get a couple of 1R resistors and try them. |
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| planet10 |
| quote: | Originally posted by runebivrin
Not to be picky, but a more useful format would be better. .CLP isn't something I know how to read.
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Converted to gif (and made larger)
dave |
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| Nuuk |
I took Carlos's advice and tried a Zobel on the output of my opamp buffered IGC and it does make a slight difference in tightening up the bass. Actually bass also seemed to go a tad lower.
Of course, CFM is never satisfied ;) and is making me try another value resistor. I think that he is on commision from the resistor manufacturers! :D |
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| carlosfm |
| quote: | Originally posted by Nuuk
I took Carlos's advice and tried a Zobel on the output of my opamp buffered IGC and it does make a slight difference in tightening up the bass. Actually bass also seemed to go a tad lower. |
That's it, that's really it.:)
Your amp is driving better your speakers than before.:cool:
The amp needs a zobel.:cheerful:
On some cables/speakers it's more noticeable, but it doesn't muck up the sound, at least in most situations.
So... I will always use it.
| quote: | Originally posted by Nuuk
Of course, CFM is never satisfied ;) and is making me try another value resistor. I think that he is on commision from the resistor manufacturers! :D |
Well... because I recommend 2.7R.
Because that gave me very good results, on my tests.
Curiously, after all the fuss, it's exactly what National recommends on the LM4780 datasheet.:clown:
One of the best datasheets BTW, very complete. |
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| Mr Evil |
| quote: | Originally posted by Sheldon
Ok, guess this is where partial knowledge is dangerous. I thought the function of the Zobel was to prevent instability of the amp due to high frequency (above audio) oscillation. If you prevent those frequencies from entering the stream, don't you circumvent the problem? Or have I got that all wrong?
thanks,
Sheldon |
That's what a Zobel network is for, but the high frequencies can enter the circuit from many places, not just at the input. EM radiation from many sources (spikes on the mains, phones, CB radio) can be picked up either through the circuitry itself or the speaker cable to trigger oscillations.
The problems that a Zobel network addresses can be very subtle. Oscillations may only start under certain conditions, perhaps when someone nearby pulls a big current from the mains (induction motor perhaps), or when a passing taxi uses its radio. Often it only occurs with longer speaker cables, or only when the are layed in certain locations and orientations (there's a particularly bad place in my room where my speaker cables have to run alongside some RF coaxial cable which has caused headaches in the past). I've made an amp that's only unstable in the summer too!
Once the oscillation starts, if you're lucky it will be immediately obvious and the problem can be addressed. In the worst case the oscillation is of a very high frequency and low amplitude, not giving any immediate signs that anything is wrong apart from a slightly fuzzy sound.
Thus I always measure the output of my amps with an oscilloscope when connected with long cables, or maybe a capacitor. Sometimes the Zobel proves unnecessary, but I only go without if I'm sure the setup isn't going to change e.g. changing cables or speakers.
I've learnt the hard way (several times:dead: ) trying to keep component counts down to a minimum, skimping on a couple of pence.
Placement is important. Putting them across the amp output terminals isn't as good as putting them on the PCB itself, with proper attention to layout although it can still help. |
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| tsmith1315 |
OK, I'm delurking...
No GC in the works here, but thoughts of a pair have been residing in my head for a while. Once a suitable enclosure and funding present themselves, I'll try a pair.
How would I go about estimating Zobel values for the chips of my choice? Is compensation more dependent on the IC itself, speaker/cable impedance, amplifier circuit, PCB layout, or what?
Links to where I should have looked before asking?
...Anyone for tennis?
Tim |
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| Nuuk |
| quote: | | How would I go about estimating Zobel values for the chips of my choice? |
I may be wrong, but I don't think the exact values are too critical.
So, if you use a 100n cap you could try resistor values of say 2R7 (which Carlos tells me is suggested in the NS application data) to say 6R8. I am currently using 4R7 on my 3875's and will try some other values when I can get hold of them. ;) |
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| carlosfm |
2.7R + 0.1uf is on the LM4780 datasheet and works very well for me.
1R and 0.22uf is also recommended for other National chips. I tested and didn't like it. It affected the treble.
If you don't have 2.7R resistors, use something around this value, even if you have to parallel two resistors.
But the cap should be 0.1uf. |
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| falcott |
| quote: | Originally posted by carlosfm
...The best result I had was two 0.47 ohm/3w carbon resitors in series with the output... |
Where is it possible to find these? I've looked over my favourite supplier's catalogues and can't find anything even close to 0R47 3w carbon. (Even the 2R7 is pretty rare.) |
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| Nuuk |
| quote: | | Where is it possible to find these? |
I don't know if they supply outside of the UK, but Cricklewood Electronics do 2 watt carbon film resistors in the lower values as shown HERE . |
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| carlosfm |
The 2R7 resistor doesn't need to be 3w.
1w or even 0.5w should be fine. |
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| MWP |
A quick question...
I assume in a bridged setup, a zobel will be required on the output of each half?
Or is on one side enough? |
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| sam9 |
| quote: | quote:
"'How would I go about estimating Zobel values for the chips of my choice? '
I may be wrong, but I don't think the exact values are too critical."
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Rod Elliot (sound.au.com) did a piece on cable termination and zobel's. I can follow all the details, but it seems to suggest that the appropriate values for a zobel depend more on the speakers/load than on the amplifier. This was in connection to a discrete amplifier, but the internal topology of many chip amps isn't that different. |
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| carlosfm |
| quote: | Originally posted by MWP
A quick question...
I assume in a bridged setup, a zobel will be required on the output of each half?
Or is on one side enough? |
I suggest that you take a look to the LM4780 datasheet, a very good one BTW.
Your question is answered at page 5.:) |
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| MWP |
| quote: | Originally posted by carlosfm
I suggest that you take a look to the LM4780 datasheet, a very good one BTW.
Your question is answered at page 5.:) |
Thanks. |
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| falcott |
Carlos, what if we were to use a 0R22 wirewound instead of the 2 x 0R47 carbon? Would the result be much the same? Less "coloured" perhaps? (I have 0R22s in my box of bits.)
And thanks, Nuuk, for the link to Cricklewood Electronics.
:) |
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| carlosfm |
Less "coloured"?:confused:
I don't think so.
If I felt that my amp was "coloured" I would throw it out of the window.:D
Wirewound resistors may make the chip unstable.
You should minimize inductance there.
Carbon or film it is.;) |
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| matjans |
i've tried the zobel for a couple of days, desoldered them again and...
The amp seems to have a little more control in lower frequencies with the zobel (but only slightly). With my b&w dm220i's a basskick in eva cassidy's 'bridge over troubled water' on live@blues alley is still a bit boomy.
Bass is also somewhat deeper than without the zobel. haven't tried the output resistors yet. our local electronics shop doesn;t have non inductive 3w resistors.
It also seems that the amp is less prone to 'click and pop' due to power line pollution. It could also be that the neighbours are on vacation ;) ...
i'm using a 2R7 0,5w el cheapo metal film resistos and a 0,1uf multilayer cap soldered between the output pins of brian's boards.
All in all, a slight change for the better! I'll keep 'em. |
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| Nuuk |
| quote: | | All in all, a slight change for the better! I'll keep 'em. |
Pretty much my findings Matjans. I have my sub amps running now so it will be another chance to add some Zobels and see what happens there. ;) |
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| carlosfm |
| quote: | Originally posted by matjans
All in all, a slight change for the better! I'll keep 'em. |
As I said, depending on the speaker cables and/or speakers, the improvement may be big, small, or (in rare occasions) any.
But I now use and recommend using it.
Yes, the amp needs a zobel.:D |
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| matjans |
does anybody know what 'multilayer' caps are made from btw? ceramic? film?
The guy at the store told me they were pretty good as small bypass caps in psu cap banks ...
i'm using 'dual' single stranded cat5 for speaker wire btw. one pair for +, one pair for -. the other two are used as a sort-of shield., connected to the chassis. capacitance shouldn;t be too high. |
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| carlosfm |
They are ceramics.
I use them for bypass, not at the big PSU caps, but at the chip, where they are needed. |
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| tsmith1315 |
| quote: | | Rod Elliot (sound.au.com) did a piece on cable termination and zobel's. I can follow all the details, but it seems to suggest that the appropriate values for a zobel depend more on the speakers/load than on the amplifier. This was in connection to a discrete amplifier, but the internal topology of many chip amps isn't that different. |
I *would* expect the speaker/cable load to be the most significant variable. Therefore, a zobel to compensate for that impedance would be quite logical. However, in that case I don't see why any particular network is recommended for a given IC.
Wouldn't the ideal situation simply (yeah, right!) be a conjugate load at the amplifier designed to flatten the impedance curve of the entire cable/crossover/speaker system as a whole?
I assume this *is* the actual function of the zobel as it is being discussed. Only implemented as a simpler, generalized form to help as it may?
Tim |
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| aHobbit |
The zobel network is there to protect the speaker from unnecessary amplified high frequency signals (which can fry your tweeters first). However, values of zobel network has to consider what speaker load is used, or else, you may attenuate usable audio frequency.
This is more true, but in conjunction with the snubber circuit (shunted RC network across the speaker out). Since the zobel coil will be presenting a high impedance to unwanted high frequency output, the zobel R will be functioning to limit the release of unwanted high freq output to certain extent (depends on speaker impedance).
The presence of snubber circuit, will enhance the zobel work, by presenting the shorting effect to this unwanted high frequency (again, the speaker output has to be considered in the values). Snubber will also kill any ringing that may occur in the amplifier system. |
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| indoubt |
Finally found some time to build the amp (and just got my specialized kit casing) I need at least another evening to finalize as I use very thin coax for the low level signals (outer dia 1.5 mm silver coax) which is a nightmare to strip properly.
I want to try a zobel as wel and have on hand the following:
Audyn caps MKP QS 400V 0.1uF which seems fine
Intertechnik MOX 5w 3.3 ohm resistor which may be too high
Alternatively I have a couple of 1ohm 10W MOX resistors
Can I use the 3.3 ohm MOX? or is this not a good resistor to use for this application. (I normaly use these in loudspeaker crossover cirquits)
I will first put them accros the speaker terminals and when the amp is run in I can put them closer to the pcb if I like them |
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| Nuuk |
| quote: | | Can I use the 3.3 ohm MOX? or is this not a good resistor to use for this application. |
Absolutely fine. You can then try other values when you can get hold of them. 4.7 uF worked fine for me. ;) |
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| fedde |
I agree that chipamps need a zobel. I currently use 2.7 ohm and 0.1 uF too. It really makes the amp much better than without zobel. Actually, I get headaches from the amp if I don't use a zobel! But I must say that environment is quite polluted with HF noise here...
Fedde |
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| Nuuk |
| Good to hear from you again Fedde! ;) |
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| pinkmouse |
| quote: | Originally posted by fedde
It really makes the amp much better than without zobel... But I must say that environment is quite polluted with HF noise here...
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I agree totally, I suspect that those that enthused over the minimising of components in GCs quite possibly lived in less EM polluted areas than Western Europe :) |
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| carlmart |
| quote: | Originally posted by Nuuk
Absolutely fine. You can then try other values when you can get hold of them. 4.7 uF worked fine for me. ;) |
You probably mean 4.7 ohm, right?
Carlos |
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| Nuuk |
| quote: | | You probably mean 4.7 ohm, right? |
Indeed, I did Carlos! Well spotted. :D |
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| matjans |
fedde: i guess you mean radio is being demodulated by the chip?
last week i added a 2nd order passive lowpass at 60kHz followed by a ad8620 with gain=3 close to the chipamps. i can now hook up any kind of cable, whatever length. before i had to use heavily shielded interconnects otherwise i had RTL FM (!). It didn;t pick anything up on the speakercable.
i can't really hear the difference with and without the buffer. Except that there's no more radio, of course... ;) |
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| indoubt |
Good to hear. Than I don't need a source to get music out of my amp:D
It is the EM and all other RF pollution that made me decide to use shielded (mini-coax) cable for the inputs to switch to noble pot and to the boards. With this, the solid specialized kits casing and the Zobel I hope that I've take sufficient measures to prevent my amp from acting as a radio. |
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| fedde |
Well, yes. Sometimes I can receive radio with my amp. But only if my volume is completely to zero (strange eh?). But I was talking about the HF noise in the air and on the mains. Luckily I now use battery for my DAC, so the noise of the mains only has influence on the amplifier (and the transport/PC). Still, the sound quality of the system varies quite a lot during the day. My house (student dorm) is stuffed with computers (>25 I'd guess) and other equipment. We have mobile transmitters nearby, radio transmitters, a wireless LAN network etc. You get my point? ;-)
Fedde |
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| jean-paul |
Input filters and Zobels are not a luxury. They are essential for troublefree operation of gear and should be implemented. IMO this is standard design practice but I see more and more designs omitting essential parts. Never underestimate the fashion of minimalistic devices ;)
The FTZ standard is another story though. |
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| matjans |
| same here, i live in a studenhuis... |
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| carlosfm |
| quote: | Originally posted by fedde
I agree that chipamps need a zobel. I currently use 2.7 ohm and 0.1 uF too. It really makes the amp much better than without zobel. Actually, I get headaches from the amp if I don't use a zobel! But I must say that environment is quite polluted with HF noise here...
Fedde |
Not only that (well... I don't have those interference problems), but, as Nuuk noticed (I was expecting someone to test it and say it), and the reason why I oppened this thread is that in my case the amp really seams to drive "any" speaker now.
Music with extreme dynamics and bass "slam" (I love this word:D ) is now tight as a rock, to the deepest notes.
Oh, the source is good, of course, otherwise, trash-in-trash-out.:) |
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| Peter K |
| quote: | Originally posted by carlosfm
the reason why I oppened this thread is that in my case the amp really seams to drive "any" speaker now.
Music with extreme dynamics and bass "slam" (I love this word:D ) is now tight as a rock, to the deepest notes.
Oh, the source is good, of course, otherwise, trash-in-trash-out.:) |
I have added the zobel to my amp yesterday. Indeed the bass is much more controlled. Before I had no problems with most Jazz and Clasical music but with the "more modern music" the bass was quit often over the top. In the new situation the amp is driving my 4 ohm speakers much better.
There is something: else some months ago I made some new cables speaker based on TNT-Audio suggestions to use CAT5 twistedpair. However I used wirewrap wire that I twisted and twisted and twisted. The result was sounding awfull! No bass, no middle, infact it sounded like nothing. With the zobel I can use the DIY cable and it sounds great, even after a day.
Peter K. |
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| carlmart |
| quote: | Originally posted by Peter K
There is something: else some months ago I made some new cables speaker based on TNT-Audio suggestions to use CAT5 twistedpair. However I used wirewrap wire that I twisted and twisted and twisted. The result was sounding awfull! No bass, no middle, infact it sounded like nothing. With the zobel I can use the DIY cable and it sounds great, even after a day.
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You probably have a power amp which is more sensitive to capacitive cables.
Your ww cable may sound even better than TNT cat5 project because it's not really twisted, as other projects using such cables are. On the TNT project you twist or braid the cat5 entire cable, not the wires inside.
But all articles involving cat5 speaker cables mention the fact that they may prove capacitive on some amps, and the cure is to use a zobel.
Carlos |
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| Peter K |
| quote: | Originally posted by carlmart
But all articles involving cat5 speaker cables mention the fact that they may prove capacitive on some amps, and the cure is to use a zobel.
Carlos |
Yes you are right, it is indeed mentioned in the articles.
The first tests that I made with a ww cable was a short cable not made very carefully, this sounded quit good. Probably because of a low capacitance (short cable quickly made). The new cables were 2,5 meter in which I twisted a total of 12 wires. The twist is very tight so the capacitance must be a lot higher. I already suspected that the capacitance was the problem, only did not know how to fix it.
I am glad I can finaly use the DIY ww cable.
Peter K. |
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| carlosfm |
Peter, high capacitance cables can't be used with these chips without a zobel.
The series resistors also help here.
The same goes for Naim amps, they sell their cables and don't recommend other ones. You can even loose warranty by using other cables.
The arrangement I posted made a big improvement with my Kimber 4TC cables. They are mid/high capacitance.
The cable and the speakers are the main factor here.
I'm sure that my amps now are much less picky with cables/speakers, in a word, more "universal".
Making an amp that only goes with a restricted type of cables and/or speakers didn't make sense to me. |
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| falcott |
Sorry, dumb question which I am sure has been answered before. I am about to impliment this Zobel on the output. Does it go to Signal Ground, Power Ground, or Chassis?
:o |
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| carlosfm |
| Welcome, Pedja.:cool: |
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| Nuuk |
| We will probably hear more from Pedja now the weather is getting cooler and the swimming pool is not so tempting! :D |
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| carlosfm |
It's not getting cooler here.:D
But I'm back to work.:bawling: |
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| Pedja |
Thanks, Carlos. Though I was here... or near. Just wanted to take a breath.
Yes uncle Nick, “the days dwindle down to a precious few” ( :note: ). Will ground myself afterward.
:wave: |
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| matjans |
"September, November . . .
And these few precious days
I'll spend with you.
These precious days
I'll spend with you."
... romantic quote, although a few days early! ;) |
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| Nuuk |
| Matjans, I didn't know you cared! :shy: |
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| Pedja |
The sun shines high above
The sounds of laughter
The birds swoop down upon
The crosses of old grey churches
We say that we're in love
While secretly wishing for rain
Sipping coke and playing games
September's here again
(this one is definitely much better to listen to than to read)
:Piano: |
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| Nuuk |
Summer was gone and the heat died down,
And Autumn reached for her golden crown,
I looked behind as I heard a sigh,
But this was the time of no reply. :sing: |
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| carlosfm |
À porta... daquela igreja... vai um grande corropio...:sing:
(C) Madredeus
Plays even better with the zobel!:D
:zombie: |
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| TaaJ |
| What's the best type of Cap to use? I'm noticing that the Multilayer Capacitor's that Digi-Key stocks have less than desireable tolerance. |
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| dickiegeorge |
:cool: Pedja - your a David Sylvian fan too? :wave:
Anything else we should know about you ?:D |
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| carlosfm |
Gentlemen
Take Polaroids
And fall in love...
And fall in love...
:eguitar: |
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| Mr Evil |
| quote: | Originally posted by TaaJ
What's the best type of Cap to use? I'm noticing that the Multilayer Capacitor's that Digi-Key stocks have less than desireable tolerance. |
Anything with low inductance. Tolerance is not important here. |
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| TaaJ |
| quote: | Originally posted by Mr Evil
Anything with low inductance. Tolerance is not important here. |
I have some Panasonic PPS Film-ECHS Caps lying around. Should have two .1 uf, just use those?
EDIT: They're polypropyene film caps, should be great. |
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| ofb |
does it matter what order the resistor and cap of a zobel are placed in?
everyone seems to use res/cap/ground. but i've noticed the gaincard and rjm's headclone use cap/res/ground. this has left me curious. |
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| ashok |
| quote: | | everyone seems to use res/cap/ground |
This is generally how it is done. The reason is that it is better to ground one capacitor terminal to reduce possibility of any RF pick up on that. If the cap has a rolled foil , it might be better to ground the outer foil . Some larger caps have that indicated. With small caps you might be able to check that out with an external foil and a capacitance meter. I haven't tried that yet.
Cheers. |
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| demogorgon |
oh well, i'm about to try this zoble thingie..
lets hope for more treble deffinition and a more dynamic bass everyone. *hold hands and pray!*:D |
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