[headphonejunkie]

I am building a cavelli jones amp and wanted some opinions on Auricaps,Hovland musicap, and Mundorf caps. Which has sounded the best and which would you suggest for a .47uf bypass cap for my 470uf electrolytics.Or are there others which are better?

 

[mrdon]

I like Auricaps myself.

BTW, what does the .47uF bypass Cap do for the sound?

 

[headphonejunkie]

From what I understand the .47uf is supposed to eliminate some of the shortcomings of the electrolyitcs. That is what was used in my millett but I removed mine because I was using blackgates caps in that amp.I have not powered up this amp yet so I cannot tell how much these will help but I am sure they should do something.I hope.mrdon,You didn't use bypass caps in your morgan jones?

 

[headphonejunkie]

You know something. I just had a revelation. I just looked back at my schematic and I don't have any bypass caps in the circuit. Where the heck did I get this from? Probably my millett. Oboy, I think I need some sleep.Good thing I didn't buy any yet. Nevermind.

Edit:
I know where I got it from. The aikido amp uses bypass caps on the output.I have two amp ideas going around in my head. I better make sure I keep them straight. Although maybe the bypass cap thing is a good idea.

 

[headphonejunkie]

Anyone have any opinions on what bypass caps on the output on the morgan jones could do? I may just try that and see what happens.

 

[headphonejunkie]

Ok. I was thinking of C2 on the morgan jones originally,but this is not an output bypass cap. This cap will probably not do too much for sound improvment but I do have a solen and orange drop I may try there.I am thinking about this amp stuff too much I think.

 

[headphonejunkie]

Ok. Did a little research and the bypass cap is supposed to give you a better sounding midrange. So, I may just try it out but it looks like I may need at least a 1ufd cap. That is what I like about DIY. You can learn so much, most of the time by your own mistakes.

 

[nikongod]

here comes a post that could stir up about as much fun as a DBT debate (but it will not involve any part of DBT, so dont ban my ass!)

for those who dont want to read the rest,
no bypass cap. that is all. just get a good quality output cap, and call it a day.

the LONG answer:
adding a bypass cap theoretically smooths a LOT of the sound of the electrolytic, but in practice it very often causes a smear in the tone of the music. when you bypass a cap you have 1 signal (assuming your amp didnt already screw it up somewhere else) going in and 2(!) coming out! the film and electrolytic caps have slightly diferent audio properties, and the signals dont always match up.

the argument is that you can bypass a $2 electrolytic with a $10 film cap and get a better sound. you could also buy a single $12 electrolytic..... which is what i would recommend.

for those who say "no mater what you should use a bypass cap, it is always better." i will proudly say "no mater what you should listen critically to the gear you make, it may make it better."

 

[cotdt]

for once i will have to agree with nikongod. just use a decent cap, no bypass cap. actually in simulations the bypass cap can create a resonance, and does not really help filter high frequencies much. the math is pretty clear.

 

[tomb]

The problem is that the above opinions apply to only one cap for certain: a Black Gate. For other electrolytic caps, this is much less clear. My own experience has been that bypasses work well. In some instances, it actually improved the bass, not just the highs. The contradictory opinion is that the two in parallel act as a single, new capacitor - with some of the properties of both, but different than either alone. There is plenty of math to support that, too.


EDIT: PS - Nikongod is correct in that this is a neverending discussion, often with lots of flame. The best thing to do is try it yourself - it doesn't take much to solder a film cap onto the pads of an electrolytic. This will tell you whether it sounds good in your circumstance.

 

[twc5964]

I'm not familiar with that amp or it's circuitry.I'm under the assumption the cap is in signal path you want to bypass ? I agree you should only use one cap but I've had very good results bypassing them in the signal path and have so far noticed no smear in sound.If your not using Blackgates try it out and see. You can always take the bypass cap off.I myself like Auricaps but I've used ICW sa series poly caps that work very good and are a little cheaper.

If you decide to add a poly cap I would not recommend you go higher than .47uf on the 470uf.

 

[AudioCats]

get a couple of 375VAC paper/oil motor caps and call it good......?

They are only like 4" long and 2" OD

 

[headphonejunkie]

Thanks guys. I will order some auricaps. They go for about 11 bucks each. that is not too bad. If they work great, if not I have some caps for my next build. I was doing the math though and it figures that a 1.5 uf would bring me down to about 3khz with grados. Why would it be bad to go above .47ufds?

EDIT: By the way I am using panasonic ts-hc 470u 350v caps. I am not sure of their sonic quality.

 

[twc5964]

Going higher may affect the sound.Not saying it will happen...just that it can induce time smear of the signal where the caps charge and discharge at different rates in time too much messing up the signal.