[Wavelength]

Gang,

I have been asked to look at a new USB DAC that I might build or someone else may. It will be a simple 24/96 dac with line and headphone output.

Since Black Gate no longer makes any new capacitors I am left looking for other possibilities and was wondering what people around here liked for headphone coupling capacitors?

I need 220uF and do NOT like the idea of paralleling caps as it smears the sound.

Suggestions?

Thanks
Gordon

 

[FallenAngel]

Yeah, if size doesn't matter, go with film caps; a few manufacturers make caps of that size. Check out the notes on coupling caps here for a nice rundown of them.

 

[tomb]

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif Gang, I have been asked to look at a new USB DAC that I might build or someone else may. It will be a simple 24/96 dac with line and headphone output. Since Black Gate no longer makes any new capacitors I am left looking for other possibilities and was wondering what people around here liked for headphone coupling capacitors? I need 220uF and do NOT like the idea of paralleling caps as it smears the sound. Suggestions? Thanks Gordon

Black Gate - they're not out of stock, yet. If you're just building one, there's no problem - either PartsConnexion or Soniccraft. Buy the NX.

 

[dsavitsk]

Hi Gordon,

I don't think there are really many good options out there right now. Besides the BGs, probably Muses of some sort, or Cerafines or Silmics. None of these, on their own, really excites me as a cap to couple to phones (though my experience with cathode bypasses says that Cerafines are the best of the bunch), however. My guess is that the smearing from a bypass will be less offensive than the lousy midrange and top end from an unbypassed electrolytic. You can see elsewhere that for a cheap option I like the Muse ES's bypassed by a Sonicap as the Sonicap basically swamps the Muse. Also, if you keep the bypass ratio large enough (470uF + 0.22uF or so), I doubt you'll hear much smearing. It really does wonders to the mids and highs. Obviously, a better film cap is better. Why not a switch to allow the user to switch the bypass in and out?

One other thing to look at, though, is that there are some Vishay type os-cons at Mouser that might do alright. I've used those and they seemed not too bad. Really, though, a bunch of parallel film caps, or one big one, or a servo is probably your best bet.

-d

 

[dcheming]

Quote:

Originally Posted by Wavelength /img/forum/go_quote.gif I need 220uF and do NOT like the idea of paralleling caps as it smears the sound.

What about using a 220uF Solen MPP?

 

[Logistics]

I noticed polymer caps have super-high leakage current compared to normal aluminum electrolytics. You could have a said voltage and capacitance in an aluminum electrolytic with 75uA leakage current, while a polymer version could be in the neighborhood of 1,500uA. I was under the impression that high leakage current is not desirable in anything audio related.

 

[Negatron]

I'm new over here in DIY but this is a good spot to weigh in. I don't know what your voltage requirements are but the BlackGate 220uf NH as an output coupling cap in OTL's has, after break-in, really screwed up some long held prejudices I have held about EL's for coupling . It's cost is something I tend to ignore by reminding myself what a quality transformer costs. The max voltage is 160, so if you are using cathode follower you're probably good to go, but SEPP is another matter. The caps are spooky after 150 hours or so in their ability to start to disappear. There is still a good supply around. If it's SS, Lotsa' options

 

[applevalleyjoe]

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif Yeah, if size doesn't matter, go with film caps; a few manufacturers make caps of that size. Check out the notes on coupling caps here for a nice rundown of them.

Great link...good info...thanks.

 

[Icarium]

Yay Gordon. Unfortunately given the quantity that Wavelength Audio probably needs cap-wise he probably either needs to stock up bad or find a true alternative.

 

[Fitz]

The best coupling cap is no coupling cap, but unfortunately some designs necessitate their use..

 

[00940]

The best caps I had as output caps on my tube amps were Audyn MKP-QS 220uf/400V. They're Solen 400V mkp caps rebranded for the European market. It was indeed quite a step-up from the electrolytics I had, especially to retrieve low level details. On the other hand, it sounded a bit "bland", less romantic.

Still, I'm not quite sure that a HUGE cap, costing 60€ a piece is really something worth considering for production. It could have a kind of weird sex-appeal though. Make sure to put it on display...

An even better coupling cap (barring paralleling) would be a Mundorf M-Cap MKP. A minor improvement in sound for just under 200$ a piece...

Seriously :
- what is the budget ?
- what is the free space to mount the cap ?
- what is the voltage sitting at the input leg of the cap ?

 

[Ferrari]

Yes, best coupling cap is no coupling cap at all. But... unfortunately it's not always possible.
In some amps designs it's an evil necessity. It's wise to be a bit selective when we have to use it.

And eehhh... Audyn MKP-QS as output caps for tube amps, bypassed with Russian teflon in my build

.

 

[Wavelength]

Gang,

Thanks for all the advice. I have about 200 of the 220uF/6.3 Black Gate N series and about 1700 of the 100uF so I may try the singles and maybe 3 of the 100uF in parallel.

If I have to parallel then only the same caps (i.e like two 100uF/6.3) the only way to go. We did some testing with fancy HP 3585A and you would be really surprised at how even two really expensive caps in parallel fail compared to a single cheap one.

Anyways I also bought some of the Mundorf bipolar caps to try and see how they fair.

I don't really have enough room for the Solen's in this size chassis.

Thanks
Gordon