Guys if you cant hear the differnce then dont waste your money. My vave are audyn tri ref and yes i can here the difference. They are not the most expensive either. Copper foil no way.
Obbligato Gold is a nice little step up from Solen black caps without breaking the bank. Discontinued and on sale 40% off at Partsconnexion.
Use a 0.1u Russian silver mica to cross them if you like clean detail in the high frequency.
Use a 0.1u Russian silver mica to cross them if you like clean detail in the high frequency.
Thanks Profiguy. I can really identify with you saying "The top end sounds rolled off with the stop caps" - this is exacly how I feel the speakers sound. This is my major issue with these speakers as the bass & mid is quite nice, in a vintage warm way using my Sansui AU-7900 - just want to brighten up the treble a bit
I am thinking either Solens or Wima MKP 10 polypropylenes, which might be easier to fit in especially if I can match the originel content spacing.
Any experinence of Wima MKP10's ?
I'm not a fan of over bright speakers. I have a set of old KEF 104 reference speakers I have recapped, but the sound is just too bright & I don't really enjoy listening to them after a few minutes - I have been looking for some cheap 104ab crossovers but without succees so far. No sure either of the relative merits of the 104ab crossover compared to the standard 104, so whether the" shouty" treble would be tamed or not.
I am thinking either Solens or Wima MKP 10 polypropylenes, which might be easier to fit in especially if I can match the originel content spacing.
Any experinence of Wima MKP10's ?
I'm not a fan of over bright speakers. I have a set of old KEF 104 reference speakers I have recapped, but the sound is just too bright & I don't really enjoy listening to them after a few minutes - I have been looking for some cheap 104ab crossovers but without succees so far. No sure either of the relative merits of the 104ab crossover compared to the standard 104, so whether the" shouty" treble would be tamed or not.
Maybe it's simply the tweeter itself. I bet it deteriorates quicker than a film cap. Have a check on the ferrofluid.
Ralf
Thanks everyone for all the advice. I'm going to order the caps today & will report back in a couple of weeks.
As far as I can make out, there is no ferrofluid in these tweeter. I may be wrong though.
I am waiting for the electrolytics to arrive from falcon, but I bought some Dayton polypropylene caps for the HF circuit. They measure increadibly close to nominal (<1%) even though they are standard 5% ones.
Anyway, I took the crossover out from one speaker yesterday and found most of the old Pye eletroytics to be way out of spec, so all in excess of +10% to 12% on the high side of nominal.
For the ochre coloured film caps on the tweeter circuit, these measure 0.68uf (for 0.47uf), 2.09uf (for 2.2uf) & 5.10uf (for 5.0uf).
On the otherhand I also found the resistance in series with the tweeter to be way out of spec too, so 7.5ohm measured for 6.8ohm nominal. I lifted a leg first on all caps/resistors before measuring them.
Can anyone confirm if such a deviation in the resistance in series with the tweeter is significant ?
The other thing is that the crossover board is really stinky, the stink you get with old capacitors in vintage amplifiers.
Anyway, I took the crossover out from one speaker yesterday and found most of the old Pye eletroytics to be way out of spec, so all in excess of +10% to 12% on the high side of nominal.
For the ochre coloured film caps on the tweeter circuit, these measure 0.68uf (for 0.47uf), 2.09uf (for 2.2uf) & 5.10uf (for 5.0uf).
On the otherhand I also found the resistance in series with the tweeter to be way out of spec too, so 7.5ohm measured for 6.8ohm nominal. I lifted a leg first on all caps/resistors before measuring them.
Can anyone confirm if such a deviation in the resistance in series with the tweeter is significant ?
The other thing is that the crossover board is really stinky, the stink you get with old capacitors in vintage amplifiers.
No just measured from side to side, of the resitor but with one lead desoldered from the board.
On the otherhand this is just within the 10% tolerance they were probably using at the time. I can but some 6.8ohm resitors with 2% or even 1% tolerance.
Any idea how the ESR of the Dayton polypropylenes would compare to the old ITT Polyester film caps in the speakers ?
Another issue is that the small film cap I removed, is actually marked .68uf, and so it measures to spec. Maybe the crossover drawing I have, which shows 0.47uf is incorrect. What was the purpose for putting 2 capacitos in series as opposed to just one capacitor of a higher value ? Just size availability ?
On the otherhand this is just within the 10% tolerance they were probably using at the time. I can but some 6.8ohm resitors with 2% or even 1% tolerance.
Any idea how the ESR of the Dayton polypropylenes would compare to the old ITT Polyester film caps in the speakers ?
Another issue is that the small film cap I removed, is actually marked .68uf, and so it measures to spec. Maybe the crossover drawing I have, which shows 0.47uf is incorrect. What was the purpose for putting 2 capacitos in series as opposed to just one capacitor of a higher value ? Just size availability ?
I meant the leads of the multimeter, not the leads of the resistor. The correct procedure to measure a resistor is to first connect together the two leads of the multimeter and read the value, and then subtract this value form the measure of the resistor. A value > 0.5 Ohm for the resistance of the leads is pretty common.
As for the caps, please show the drawing, two caps in series don’t add.
Ralf
As for the caps, please show the drawing, two caps in series don’t add.
Ralf
Thanks Ralf, you are right on both counts !
For the leads, when I touch them together I get 0ohms, but very ocassionally it flashes 0.3 ohms then goes back to 0. I guess this means 7.2ohms
I tried a second DVM I have and measure 7.2 ohms & 0.1 for the leads making 7.1 ohms.
Question is, is this significant or not for restricting the tweeter output.
For the caps, this was a brain fart, and I meant to say in parallel ! Sorry for the confusion. Still wondering why they put 2 caps in paraellel. I was wondering if they did this to allow them to match available caps in the factory to get a more precise final value. This is the drawing I have :
For the leads, when I touch them together I get 0ohms, but very ocassionally it flashes 0.3 ohms then goes back to 0. I guess this means 7.2ohms
I tried a second DVM I have and measure 7.2 ohms & 0.1 for the leads making 7.1 ohms.
Question is, is this significant or not for restricting the tweeter output.
For the caps, this was a brain fart, and I meant to say in parallel ! Sorry for the confusion. Still wondering why they put 2 caps in paraellel. I was wondering if they did this to allow them to match available caps in the factory to get a more precise final value. This is the drawing I have :
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Also the old film caps (ITT -GB PMT/2R UK) are actually metallized polypropylene caps and according to some sources are very good quality. Bit confused now.....
Took out the crossover from the second speaker. Wow every single electrolytic cap was massively out of spec from +25% to +80% above spec ! Once was even leaking badly. Also the magnet on the woofer is covered with a thick white powder, so some sort of chemical attack.
About the 3 film caps they were spot on, except for one slightly above tolerance.
What is strange is that the caps on the tweeter circuit differ from the drawing.. Also the crossover is marked with "B&W DM2ii issue 3", so I reckon a production change towards the end of these speakers. Mine were built in October 1979
About the 3 film caps they were spot on, except for one slightly above tolerance.
What is strange is that the caps on the tweeter circuit differ from the drawing.. Also the crossover is marked with "B&W DM2ii issue 3", so I reckon a production change towards the end of these speakers. Mine were built in October 1979
