Fizz/Treble Caps - Composition and Sound

[Kramer]

Hey everybody, I'm getting back into researching the specifics of my next build, and something that isn't talked about a whole lot or seems to be eluding me is what kind of capacitors (used in PI and treble positions) generally sound good/generally sound bad/generally sound like this:, etc. So what do you all prefer? There are the normal silver micas that you can get for real cheap and then ceramics which are also cheap, and then you can get into the NOS variants of those two types which can range up to $20 per cap. I've seen a few people using the Lemco Silver Micas, so what do you people think about them? What have you guys found makes a difference, or is there really no difference at all with these things?

Many Thanks, and Happy Holidays!

alex

[VelvetGeorge]

I love old single layer ceramic disks or old stock silver micas. Modern silver micas are decent too. Modern ceramics are mostly bad sounding to my ears.

george

[Roe]

I'm not happy with modern silver micas for the plexi sound - they sound too smooth and lack the aggressive snarl of old plexis. some of the higher voltage reading ceramic caps can be nice, they have a dirtier sound without sounding as harsh as the lover voltage ceramics.

I've pretty much replaced all these treble/fizz caps lately in my plexis, partly with nos tonebone lemcos. I'm much closer to the aggressive marshall snarl now

[shakti]

So the cap type in the PI matters too, huh?

On the same subject; how high can you go with the fizz cap value before it starts to roll off high end? 56pF? 70pF? 100?

[Kramer]

From what I've heard the PI cap certainly does matter; a few people like to use 100 pF. See this thread for more info.

Where did you source your Lemco's from Roe?

[Roe]

I got several of ebay over the last two years. also a few from rich m at plexipalace

[Roe]

From what I've heard the PI cap certainly does matter; a few people like to use 100 pF. See this thread for more info.

Where did you source your Lemco's from Roe?

yes, 100pf will give less highend than 50pf. but what about 68pf etc?
and more importantly (in the context of this topic): will the type of cap make an difference?

[myfoot]

I got several of ebay over the last two years. also a few from rich m at plexipalace

Isn't that Sparky from here?

[Roe]

I got several of ebay over the last two years. also a few from rich m at plexipalace

Isn't that Sparky from here?

No, not as far as I know

[shakti]

Yes, sparky and Rich M is the same person. Great guy to deal with!

Back on topic...what do people find when changing...

- tone stack treble cap from silver mica to ceramic (the 250 or 500 pF one)
- PI "fizz" cap from silver mica to ceramic (the 47 pF one)

...and how much higher than 47pF can you go before the high end gets rolled off to a noticeable degree?

[Roe]

I can easily hear the difference when it comes to the 500ish cap on the mixer resistor as well as the 250/270/470 cap in the tone stack. the new silver micas (most of which I got from metro) sound too polite and smooth. some newer ceramics, sounds harsh. but some sound pretty good.
before I found some NOS stuff I used metro's ceramic across the mixer resistor and the silver mica in the tone stack

[Kramer]

I saw these and thought they looked good..maybe not NOS ball park, but maybe a step over the normal silver micas.

http://www.tubeampdoctor.com/index.php? ... 0719f6722c" onclick="window.open(this.href);return false;

[Roe]

It been a while since I tried the TADs but I dont remember the TADs being better than the silver micas george sells.

[RockingJTM]

Is it also possible to use NOS mustards instead of silver mica caps or ceramic caps.
Does anyone try this yet? and how does it sounds?

[PCollen]

From what I've heard the PI cap certainly does matter; a few people like to use 100 pF. See this thread for more info.

Where did you source your Lemco's from Roe?

yes, 100pf will give less highend than 50pf. but what about 68pf etc?
and more importantly (in the context of this topic): will the type of cap make an difference?

68 pf will give a little more highend than 50 pf, and a little less than 100 pf....