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elwood127
12-15-2008, 11:06 PM
Hey guys, I was reading recommendations for this brand off caps. It says not to bypass thier caps unless in a power supply. Goes against what I've read here. Quick read.
http://www.audience-av.com/capacitors/a_applications.php

4313B
12-16-2008, 03:02 AM
and what other people are doing with theirs. :p

Like Greg said, do whatever you want.

If you don't know what you want to do then follow the manufacturer's recommendation. They should know how to use their product.

Ducatista47
12-16-2008, 07:37 PM
I can't disagree with what they are getting at in the instructions. Auricaps are of the quality used to bypass lesser caps, so it would be silly to bypass them. It begs the question, with what?

Clark

Allanvh5150
12-16-2008, 08:05 PM
One would first need to ask the question "why do we bypass capacitors"?:)

Ducatista47
12-16-2008, 09:52 PM
Well, I can tell you why I bypass caps sometimes. A long time ago, few if anyone believed that passive components had any effect on the audio signal. When better capacitors became available, there was something to compare to and many, including myself, subsequently felt that better caps in the signal path yielded better sounding playback.

Fast forward to now. A friend rebuilds a crossover for me. We can't afford the quality we would like for the high value caps, good stuff but not what we like to hear, so we bypass with what we do like to hear and all is good with the listening experience. Later I buy a speaker kit and the notch filter and high bandpass filter parts are not as good as I would like. A solution I can afford, buy a few .01 value Auricaps and bypass the big boys.

Works for me. Worked for JBL when they designed the 3145 crossovers. Doesn't work for Canton speakers because they come with Mundorfs. Doesn't work for my Grommes tube amp because the point to point wonder comes with Auricaps.

Clark

Ian Mackenzie
12-17-2008, 12:21 PM
Sometimes it works and other times it does not.

With really budget capacitors ( metalised polyester or mylar) its a no brainer but people then use an equally budget bypass capacitor and its often too large.

Its a case by case thing and you dont always need to bypass

Different types of capacitors sound different as bypass capacitors.ie polypropolyne, polystyrene.

What you decide on also depends on what the filter is for. Sometimes it can result in an effect that is too hot in the top end.

Auricap dont recommend bypassing their own product. I would not argue but why have they introduced Teflon capacitors.

Having done it all I would advise using the budget capacitors and then bypass with something like what 4313 says in many threads.

The next step go the Solen Fast cap and charge couple (dont worry about bypassing). It works.

There are a lot of "me too" polyropolyne capacitors around that are really just alternatives to the charge coupled approach so I would not look to them as being better, they are just different.

To go better you need to spend a real lot of money and only then that look at Mundford silver Oil or Dueland which dont require bypassing. You are talking 4or 5 x the cost of charge -coupling at least and unless you have a serioous investment else where in your system its not necessary.

jcrobso
12-18-2008, 02:20 PM
One would first need to ask the question "why do we bypass capacitors"?:)
Take two sheets of foil(2"X12") place a insulator between the sheets and press the sandwich together. Now attach a wire to each foil and you have a capacitor. But it is rather large so you roll it up to make it smaller. Now with the capacitor rolled up you have the same capacitance, but you now also have some inductance. This is an undesirable by product of rolling the capacitor. The effect of this on the audio signal can be seen on a scope.
the high frequencies can suffer, to compensate for this a small cap is placed in parallel with the bigger one. The highs will easily pass through the smaller cap and the lows pass through the bigger cap. Usually 5~10% of the total capacitance is used in the smaller one. Hope I didn't bore you with the details.:blink: John

Allanvh5150
12-18-2008, 04:58 PM
Hi John,

Brilliant response. I was waiting for that exact answer but no one came back with it. You could have also said that the total inductance will be smaller than the smallest cap, that is the reason why the bypass cap is kept small. i.e. .047 or .1.
:)