Power rating affecting sound?

[gutsofgold]

I've read a few statements here that the power rating of resistors and voltage rating of caps actually affects tone.

On a technical level how does this make sense if the power rating is mostly a 'safety' measure. Does a guitar pedal circuit ever reach anywhere near 1/4 watt at the resistors? And if its only a 9v circuit how can using a 1kV cap be any different than 50v? I'm assuming it has something to do with the  composition/construction of higher volt caps?

[Mick Bailey]

Just to argue the case;

It may do, just as some people can 'hear' the difference between brands of solder. The problem with putting higher rated components into pedals is the physical size and I tend to think that the device construction is the more important factor - eg, carbon film, carbon comp, metal film etc. I can honestly say that for a given brand and identical construction of capacitor I can't hear any difference between a 400v cap and a 50v cap. Or maybe it's just my hearing.

I misguidedly replaced all of the 1/2 watt resistors in my first valve amp with 2 watt and it made absolutely no difference. If it did, wouldn't Marshall be putting 5w or 10w resistors in their amps?

If you look at what commercial manufacturers put into their pedals, they're the lowest rated components that will adequately do the job in a given circuit. I don't think that anyone would argue that that commercial pedals sound 'bad' because of this. I've never repaired or seen a commercial pedal with 400v or 1Kv components and given the highly competitive nature of the business if this was a factor, it would be used as a marketing angle; "Improved Mojo-Tone, now with 500% extra Mojo with 1Kv components - hear the difference at your store today!"

Consider the size and close rating of SMD components - do these sound 'bad'?

[Mark Hammer]

It is entirely conceivable that the materials or process required for manufacturing much higher voltage-rating caps have some properties that work in favour of guitar signals.  Obviously not in spite of everything, and obviously not intentionally so, but sometimes things just "work out" for serendipitous reasons.  It's not like Viagra was initially developed to be for, um, "life enhancement" purposes.  It started out as something entirely different, much like the adhesive that "sticky" note pads depend on.  The same things can happen with components too.

Now, being within the realm of possibility, and being actually true, can be two different things.  So, I'm not saying there IS a difference, or that there HAS to be a difference.  I'm merely sayng that there COULD be, but it would require more refined testing and measurement to verify.  Personally, in view of the too-many-things that musicians tend to confuse and confound, I'm not betting my life savings on it.

[gutsofgold]

I don't think I'll put much stock in it myself. I was also prompted to ask because I noticed a lot of vintage effects (mostly distortions and fuzzes) used 1/2w and even 1watt resistors and those are usually the sought after tones.

[Mark Hammer]

Old pedals = big parts.  New pedals w/SMD = pretty decent sound too.

Maybe the "mojo" here is that people applying way too much heat to medium-small parts in the process of trying to clone old pedals produces some problems.  In other words, it's not the parts themselves, but how easy they are to mess up with bad soldering practice.......Maybe.

[Mick Bailey]

In general, older equipment does have bigger parts. Given that the tolerance of a standard resistor's value used to be on average 10%, and that could drift with heat and time, It's conceivable that the power rating would have a tolerance also. Therefore 1/2 watt may have been a safe rating, given that old carbon comp resistors could drift off by up to 20% after a few years.

It was also probably easier to make larger components consistently 30 or more ago.