bypassing electrolytic capacitors

[kivanculgener]

Hi all,
     My searching about some upgrades is continuing.i need info about prosedure of bypassing electrolytic caps. (talking about 220uf 250v and 100uf 450v caps) is it posibble to bypass all electroliytics with same value film cap.(for example with 0.22 uf 600 v Hovland supercaps)if this cap or value is wrong can you give me a spesific value and  brand name. How is the prosedure? Ä°s it only solderring this cap's two axial leads to electrolytic cap's + and - leads.?.Ä°s it that simple?i am affraid these are very silly questions and i am taking your time but this will be my first diy project and i am not a technician.A little patience can be very supportive for me. .Thank you already for help.

[Doc B.]

The process of selection requires some knowledge of ESR, bandwidth of the circuit components, etc. It might be an upgrade, i.e., it might  improve the sound - and it might not. To make this a paint by numbers kind of thing just pick something around .1 to 1 uF and make certain it has as least as high a voltage rating as the cap you are bypassing. It goes in parallel with the existing cap, as close to it as possible to keep the lead length short.

[kivanculgener]

Hi Dan;
    Thank you for info.Ä° am afraid i know nothing about ESR or components bandwidth.But i want to try anyway.Lastly ; if i go for this direction should i pypass all of electrolytics or select some of them for this purpose?( in this case would you please specify the location numbers)

[Doc B.]

It can go on any of them. Attach it to the same terminals that the electrolytic is attached to.

[kivanculgener]

Hello again;
   Can i put 0.1 uf 630 vdc (arizona cap) capacitor between 5U and 6U to bypass the 250uf 220v electrolytic cap?
i am asking because there is also a 0.1 uf metal film cap which is feeding this electrolytic.Thank you.

[kivanculgener]

OR Perhaps .22uf plus 0.1 uf together.Will this be tooo much??.

[corndog71]

I've tried it but I'm not sure how effective it is.  I know one amp manufacturer who discourages this practice as it does no measurable good in a power supply.  Now replacing those power supply electrolytics with film caps such as Clarity TC caps can make a positive audible difference in my experience.  The downside is that they are very large.

I've tried bypassing line level caps in the signal path (eg. preamp output caps)  but found them to make the sound worse.  It could have been the cheap caps I was experimenting with so YMMV.

Caps in speaker crossovers however can benefit from bypassing with a 0.1uF film cap however the bypass should be the same or better quality than the cap being bypassed.  Teflons work well.

[tubenerd]

OR Perhaps .22uf plus 0.1 uf together.Will this be tooo much??.

by together (if placed properly in parallel) you will have a total capacitance of .32uF, since caps placed in parallel will add together. I think the idea here is that one should try it and see if it makes an audible different. If so, keep it in, be happy. If not, remove it; no harm and no foul.

If you are making changes, make them incrementally but duplicate for each channel. In this way you can make better subjective assessments about the effect of your change. I would also recommend that you allow each of your changes to age in the circuit...don't make assessments until after you have played music through the unit with for a number of hours. I have heard components "form" in a circuit. They sounded horrible for the first 20 hours or so but then things clicked right in. Your experience will be different than mine, no doubt, and I wish you the best of luck.

[Doc B.]

Hey Brad! How the heck are you?

[tubenerd]

Oh man, so many changes afoot. I will email you to catch you up...read and reply only as you have the time.

[kivanculgener]

Hi corndog71 and tubenerd;
   Thank you for your replies.1 gave a desicion and will keep the kit in original form .Actually i don't have much knowlage about electronic and shematics.it is realy scary for me to play on kit and change  some parts.Perhaps in future i can try these mods but not now.Your experiences very important for me.Thank you again.

[tubenerd]

kivanculgener, your questions are good ones though. The cool thing about Bottlehead designs are they are using very innovative topologies that are not commonly found (if at all) in other kits or manufactured products. As such, the Stereomour topology and operating points have been very well refined over the history of the product line. Understand, most of the tweaks throughout our hobby are to cure the ills found in the implementations of other company's traditional topologies. The Bottlehead team isn't just recycling the same old single-ended circuits, the are innovating their own path! These designs are unique, well-vetted, and very well supported.

If you have not already, go here: http://bottlehead.com/bottlehead-technology-story/

You will enjoy the kit stock, and while tweaks can be fun, at most you MIGHT hear very small increments in musical enjoyment.  I support and encourage you to build it stock and enjoy the heck out of it. Later, if the mood strikes, then modify. Get your legs under you first, and I wish you the best.

[kivanculgener]

tubenerd thank you for your comments.i am building as stock.i am very sure that i will get to much fun.i wish you the best too.