I've never been able to measure any sonic impact of the Nichicon MUSE UES-series. I don't see widespread complaints about the sound of the Modulus-86 either. So it seems like a non-problem, thus requiring no solution.
Any sonic impact of the two UES-series capacitors would be about two decades below the audible spectrum, thus, inaudible.
Most have commented that they prefer the sound signature of the Modulus-86 Rev. 3.0 (which has the UES caps) to Rev. 2.4 and below, which does not have the caps. So maybe there's more to sound signature than a couple of capacitors.
Tom
Any sonic impact of the two UES-series capacitors would be about two decades below the audible spectrum, thus, inaudible.
Most have commented that they prefer the sound signature of the Modulus-86 Rev. 3.0 (which has the UES caps) to Rev. 2.4 and below, which does not have the caps. So maybe there's more to sound signature than a couple of capacitors.
Tom
The UES capacitors don't make noise either.
A 100 uF, 35 V film capacitors would be the size of a hand grenade and incredibly expensive. It would offer higher ESR and ESL than the electrolytic capacitor, hence, be further from an ideal capacitor than the UES.
But you're absolutely right that a large film capacitor would command attention from some audiophiles. I doubt Duelund has any issues selling their components for example. But I cater to those who value science and engineering higher than marketing babble and urban legends.
It's no secret that the Modulus-86 contains two capacitors in the signal path. That's immediately obvious from the information available on the Modulus-86 Product Page. If that doesn't suit your fancy, you can either omit the capacitors (and get higher DC offset) or you can realize that it doesn't tickle your desires and keep scrolling. I'm fine either way. This is DIY after all and we don't all have to like the same stuff.
Tom
A 100 uF, 35 V film capacitors would be the size of a hand grenade and incredibly expensive. It would offer higher ESR and ESL than the electrolytic capacitor, hence, be further from an ideal capacitor than the UES.
But you're absolutely right that a large film capacitor would command attention from some audiophiles. I doubt Duelund has any issues selling their components for example. But I cater to those who value science and engineering higher than marketing babble and urban legends.
It's no secret that the Modulus-86 contains two capacitors in the signal path. That's immediately obvious from the information available on the Modulus-86 Product Page. If that doesn't suit your fancy, you can either omit the capacitors (and get higher DC offset) or you can realize that it doesn't tickle your desires and keep scrolling. I'm fine either way. This is DIY after all and we don't all have to like the same stuff.
Tom
Great. Now go measure the distortion of a 100 uF, 35 V Nichicon MUSE UES-series when loaded by 2.2 kΩ, ±0.1 % metal film. Let me know what you find.
Here's the distortion of the Modulus-86, including the two Muse UES caps, at just below clipping levels. Let me know which part of this distortion curve you believe is from the capacitors.
Tom
Here's the distortion of the Modulus-86, including the two Muse UES caps, at just below clipping levels. Let me know which part of this distortion curve you believe is from the capacitors.
Tom
My reading of Self’s book is not “Do not use electrolytics in the signal path” it is “When you use an electrolytic in the signal path, ensure that it is sized such that there is always less than 80mv across the capacitor at the lowest frequency of interest.” Not following that advice means you would see a kick in distortion at low frequencies. There is no such kick in Tom’s distortion graph which means that Tom has done this correctly.
If you’re so hung up about it why don’t you design and market you’re own version?An electrolytic capacitor introduces distortion, this is a fact.
If the goal is to minimize distortion of the audio path, then electrical capacitors should be eliminated. This is the logic.
When you make the next version you can take this fact into account.
Except that the evidence suggests otherwise. Done right it isn’t a problem.But it’s better when there are no capacitors in the sound path
Anyway, I don’t want to derail Tom’s thread. I’m pretty sure this has been discussed elsewhere and I think Nelson has a capacitor thread going somewhere here. That might be a better place to discuss the merits of what type of capacitor to use, if any, for signal coupling.
Suffice to say that if I had the budget to build a few more amps, Tom’s would be at the top of my list. (Not that I think they are unduly expensive, it’s just that I’ve already spent as much as I can reasonably justify on amplifiers already).
Bruce Hofer of Audio Precision fame has made similar observations.My reading of Self’s book is not “Do not use electrolytics in the signal path” it is “When you use an electrolytic in the signal path, ensure that it is sized such that there is always less than 80mv across the capacitor at the lowest frequency of interest.”
It's like many other things. A tool in skilled hands can produce great results. The same tool in unskilled hands can produce disaster.
Yep. Measurements don't lie.Not following that advice means you would see a kick in distortion at low frequencies. There is no such kick in Tom’s distortion graph which means that Tom has done this correctly.
Tom
- Home
- Vendor's Bazaar
- Modulus-86: Composite amplifier achieving <0.0004 % THD+N.