Ceramic vs Mica...?

[thyx]

Lot's of discussion recently on signal caps of the film variety, but I don't remember seeing anything on the lower value caps as used for Treble and Brightness, etc. It seems the standard is ceramic disc, but I was wondering if anybody had tried silver mica and had an opinion as to what it did to the sound in a Dumble. Subjective opinions please!

[mlp-mx6]

http://ampgarage.com/forum/viewtopic.php?t=9780

[Bob-I]

Lot's of discussion recently on signal caps of the film variety, but I don't remember seeing anything on the lower value caps as used for Treble and Brightness, etc. It seems the standard is ceramic disc, but I was wondering if anybody had tried silver mica and had an opinion as to what it did to the sound in a Dumble. Subjective opinions please!

There's been tons of discussion but subjective opinions are important to me. IMHO there's too much talk about what the big guy would do.

I've tried swapping SM with ceramic, and a variety of both. IMHO the ceramics have a grain to the highs that just make the tone what I want to hear. SM's are more brittle/sterile to me, but that said, I have one amp where the SM on OD master bright cap just sounded right.

A little while ago a friend came over with an amp that just didn't sound right in the highs. I swapped the SM treble cap with the same value ceramic and it just came alive. In my (sorta) TrainWreck Rocket like amp I tried ceramic on the treble cap, terrible, the SM did the trick.

Bottom line, these caps are really really cheep. Buy a bunch and experiment.

[Funkalicousgroove]

I've seen plenty of Dumbles with SM's, don't fear them just go with what sounds good in your personal amp- there is no wrong answer so long as it makes the sound you want to hear

[talbany]

If you go with the ceramics here is a tip if you want to spend the time... They sound different depending on the direction...Also tones very slightly cap to cap so try several.. I will get out the alligator clips and try a few as Bob says they're cheap in both directions you will be surprised at the difference.. Listen for smoothness or smoother!!..Don't go nuts with it I'll pick the one I like say out of 3 or 4..
(You will get some buzz from the clips that's OK test away!!) Good Luck..

Tony

[Cliff Schecht]

What audible difference between different ceramic types (i.e. C0G/NP0, X7R, etc..) have you guys heard? I would think that C0G have the least amount of distortion because they have the lowest dielectric absorption but not necessarily the most desirable sound.

I almost always use Silver Mica or Polystyrene caps because I have a crap ton of these and not many low value ceramics. Poly's sound the best IMO.

[Max]

Lot's of discussion recently on signal caps of the film variety, but I don't remember seeing anything on the lower value caps as used for Treble and Brightness, etc. It seems the standard is ceramic disc, but I was wondering if anybody had tried silver mica and had an opinion as to what it did to the sound in a Dumble. Subjective opinions please!

As far as I know Alexander has tried silver mica and obviously liked them for some applications (As far as I remember for some "Skyliner" tonestack mods e. g.).

Cheers

Max

[llemtt]

saying ceramic alone doesn't have much sense to me, they are completely different depending on dielectric and voltage rating

two weeks ago I replaced a Y5U treble cap in one of my amps with a SM because it was causing to much 2nd order harmonic and this was causing unpleasant sounds at certain frets position on high strings on a maple neck strat (not an uncommon problem with maple strats)

the SM solved the problem and now it's a lot smoother sounding with that strat but maybe it became a little too smooth with humbuckers and rosewood...

a C0G ceramic would behave very similar to the SM but I haven't any under hand

components (cap, resitors, tubes,...) DON'T HAVE any "sound" inherent to them, they only have different properties that let the circuits they are used into behave differently

you can think of SMs as the most linear and stable low capacitance caps available

but you can use them to obtain lots of different "sounds"

my .02

[Max]

I've seen plenty of Dumbles with SM's, don't fear them just go with what sounds good in your personal amp- there is no wrong answer so long as it makes the sound you want to hear

Yep!

Hope you are fine!

All the best

Max

[brewdude]

I currently have a parallelled combination of 390pF silver mica with a 100pF ceramic. I was simply scrounging around trying different combinations of what I could find or scavenge around the house. The original goal was to taste some different treble cap values. This was the combo that gave closeest to 500pF. So far, it's the value that has stuck. I will eventually stock up on some assorted values of both types and try 500pF of each type individually and peraps a 250pF/250pF equal proportion combination.

[Bob-I]

If you go with the ceramics here is a tip if you want to spend the time... They sound different depending on the direction...Also tones very slightly cap to cap so try several.. I will get out the alligator clips and try a few as Bob says they're cheap in both directions you will be surprised at the difference.. Listen for smoothness or smoother!!..Don't go nuts with it I'll pick the one I like say out of 3 or 4..
(You will get some buzz from the clips that's OK test away!!) Good Luck..

Tony

I've tried the aligator clip thing but felt that it didn't reflect the sound I got after I soldered. Maybe it's tone memory, but I felt the clips changed the tone. Same for tacking in a component with just a little solder.

The closest I came was soldering aligator clips into the eyelets, but still I felt there was a change when I soldered the component in.

[max_lwedge]

Steve's Tube Pages have scope traces of different capacitor types. All of them have some sort of curve, and definitely hysteresis in some. Ceramics have a lot going on, almost like an active device, and there is a big difference between high and low voltage. You ears are still the guide, but it is an interesting look.

http://greygum.net/sbench/sbench102/caps.html

[Colossal]

I currently have a parallelled combination of 390pF silver mica with a 100pF ceramic. I was simply scrounging around trying different combinations of what I could find or scavenge around the house. The original goal was to taste some different treble cap values. This was the combo that gave closeest to 500pF. So far, it's the value that has stuck. I will eventually stock up on some assorted values of both types and try 500pF of each type individually and peraps a 250pF/250pF equal proportion combination.

'dude,

Did you notice a discernible difference when paralleling two caps of different composition vs. just going with the one type? I've been very interested in this which is why I ask. Polystyrene is reputed to take some "edge" off that ceramic or siver mica might bring, but edge can be a good or bad thing depending on the amp of course. But, mostly I'm interested in the utility of blending caps; if there is a gain in complexity and if you can actually hear the qualities of both caps or if by blending them, the sum becomes something altogether different.

[brewdude]

I currently have a parallelled combination of 390pF silver mica with a 100pF ceramic. I was simply scrounging around trying different combinations of what I could find or scavenge around the house. The original goal was to taste some different treble cap values. This was the combo that gave closest to 500pF. So far, it's the value that has stuck. I will eventually stock up on some assorted values of both types and try 500pF of each type individually and perhaps a 250pF/250pF equal proportion combination.

'dude,

Did you notice a discernible difference when paralleling two caps of different composition vs. just going with the one type? I've been very interested in this which is why I ask. Polystyrene is reputed to take some "edge" off that ceramic or siver mica might bring, but edge can be a good or bad thing depending on the amp of course. But, mostly I'm interested in the utility of blending caps; if there is a gain in complexity and if you can actually hear the qualities of both caps or if by blending them, the sum becomes something altogether different.

I noticed some differences, but I was also changing the total value of the treble cap. I have not had the opportunity to do the test with similar values for each individually and combined. However, I believe that there could be benefits to blending caps. Unfortunately, I am broke and don't expect to be placing any parts orders in the immediate future.

I would love to hear anyone else's experience and opinions on this.

[erwin_ve]

If you go with the ceramics here is a tip if you want to spend the time... They sound different depending on the direction...Also tones very slightly cap to cap so try several.. I will get out the alligator clips and try a few as Bob says they're cheap in both directions you will be surprised at the difference.. Listen for smoothness or smoother!!..Don't go nuts with it I'll pick the one I like say out of 3 or 4..
(You will get some buzz from the clips that's OK test away!!) Good Luck..

Tony

That's interesting! Never heard anybody talk about it. Thnx! Have to try this.