Your thoughts on Filter Caps.

[StratTone]

Ok, so I have noticed that certain amps don't care what type of filter cap it is replaced with in the power supply as far as tone goes.

However IMHO fenders seem to not quite sound the same when you replace the doghouse with Atom Drops............

Is it just me? Is there such thing as possible the Atom Drops being too good of a cap and cleaning up the DC to much thus making clean amps like Fenders sound a little thing or sterile?

Put some TADs in a '67 twin vs Sprague and they sounded great. I'm thinking about putting some Sqragues in there just to see if I'm crazy or not.

Your thoughts? I see tons of threads on polyester vs polyprophele, ceramic vs silver mica but not a lot of talk of whether people prefer a less effeiciant filter for the power supply.

[MWJB]

I've replaced filter caps in many, many Fenders with Spragues, as well as F&T, some TAD caps & some Asian "HL" caps. I have never noticed, or had it pointed out to me by a client that Spragues have ever made an amp sterile or thin. The amps in question have always sounded better after the cap job as opposed to before.

Which begs the question, is it the brand of cap that you are hearing, or simply the fact that the new cap is performing properly?

To test whether one brand of filter cap sounds better than another (I'm certainly not ruling it out) you really need 2 identical sounding amps to start with & just have different brands in them & compare with an A/B test. I think that listening to an amp with one brand of cap, removing them & replacing with another brand of cap, then listening to the amp again hours later, would be too much of a stretch for many people to make a definitive comparison.

Victoria, Clark, Kendrick and many other respected builders (who also get the opportunity to compare & A/B test amps) use Sprague Atom filter caps in their builds...if they were tonally deficient they would have noticed.

There does seem to have been a shift away from Sprague Atoms by various parties in recent years, but I thought that this was prompted by Spragues price hikes.

[StratTone]

Yeah I'm really thinking this amp in paticular just has "it". I've also just some jobs for guys who didn't want to spend a lot and put Nichicon in there amps and they sounded fine to me.

Not sure whether I believe the filter brand matters to much.

[tedmich]

Short answer: unless a real difference in some quantity that can be accurately measured (esr, Q, dissipation), you should take a ~100h "break in period" before judging the replacement caps.

longer rumination:
PS caps are at best a subtle effect on tone. The degradation of the cap very slowly changes the amp from new to old and in the case of an amp played ~1 weekly there is just too slow and subtle a change for most to perceive; you are acclimated to the current sound. Its a bit like noticing you (or your parents) hair turning gray. Humans are notoriously deficient at perceiving these subtle slow changes. Once you decide to get a "cap job" the change back to a fully functioning cap, along with the more subtle tone change from different cap types, lower ESR, etc. makes it sound quite different, and different can be defined as "bad" for highly subjective quantities like "tone".

This is why audiophiles maintain that their incredibly overpriced capacitors (I have seen ~10uf for $5k) require extensive "break in" periods (see the Sozo web site). The reality is that what you are "breaking in" is your brains perception of, and feeling about, the sound. A psych term related to this affect is "psycho acoustic masking". Marketing is needed to counteract this tendency, another counterforce being the deeply seated desire in some to keep "tweaking" their systems with purchases ("upgrades" or "mods"): a lucrative and antiscientific type of retail therapy.

An interesting extension of this is a sort of an inverse "break in" phenomenon; audiophiles who previously swore by their new PS SiC schottky diode's, hemp/silk dielectric capacitors, tantalum resistors, super fast op amps etc. and then decide they sound "artificial" "sterile" "obtrusive" "forward" "harsh". This is MUCH more related to the good feeling most everyone gets when buying, or unwrapping, a shiny new toy. Unless there is a real "3db effect" (see Steve Conner's 3db Club) on something measurable its highly likely you are chasing a subtle human brain bias which will very seldom (if ever) respond to the empirical method.

Some audiophiles embrace this (ir) rationale: they perform endless empirical experiments with only subjective "metrics": a practice which not coincidentally supports an entire lucrative industry. I am not saying anyone's judgments are WRONG, but I think its best to fully explore what (and who) motivates such non quantitative judgments (aka feelings).

[Jazz P Bass]

Retail Therapy

Kind of like Scientology.
How about "Musictology"
The science of spending money on perceived differences with absolutely no concrete data to back it up.

[StratTone]

Kind of like Scientology.
How about "Musictology"
The science of spending money on perceived differences with absolutely no concrete data to back it up.

Off topic but makes total sense.

[R.G.]

Kind of like Scientology.
How about "Musictology"
The science of spending money on perceived differences with absolutely no concrete data to back it up.

ROFLMAO!!

But I'd make it "music-toy-logy"