Welcome To the Hoffman Amplifiers Forum

September 08, 2025, 05:44:21 am
guest image
Welcome, Guest. Please login or register.
-User Name
-Password



Hoffman Amps Forum image Author Topic: Silver Mica vs Ceramic caps for treble?  (Read 15051 times)

0 Members and 1 Guest are viewing this topic.

Offline markmalin

  • Level 3
  • ***
  • Posts: 827
  • Malin Sweet Loraine
    • Malin Amplification
Hoffman Amps Forum image
Silver Mica vs Ceramic caps for treble?
« on: June 09, 2016, 09:27:10 pm »
I'm wondering what the consensus is.  If I use a Silver Mica or a Ceramic cap for a treble cap (for example, the 500pf in an AC 30), is one better sounding?  I've gone back and forth, for a while I was thinking the Mica caps sounded more musical and the ceramics more harsh...Does anyone have a strong opinion on these or is it six of one, half dozen of the other, so to speak.

Mark
"... there are Flying V's and then there are the ones shaped like peanuts..."  - my son at age 9

Offline PRR

  • Level 5
  • *******
  • Posts: 17082
  • Maine USA
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #1 on: June 09, 2016, 09:40:21 pm »
Below 1,000pFd, NP0 ceramic is as perfect as it gets. Any "tone difference" is the cap color, or price, not its electronic action.

Over 1,000pFd, ceramics increasingly tend to be made of ugly-stuff to get the rated pFd in small space. C varies with voltage, enuff for a critical ear to hear.

Offline HotBluePlates

  • Global Moderator
  • Level 5
  • ******
  • Posts: 13127
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #2 on: June 09, 2016, 10:06:01 pm »
And be aware that NP0 ceramic is one of (at least?) 3 different varieties of ceramic caps.

And if you buy NP0, make sure to check a data sheet for lead length. Many have very short leads (for p.c. board work).

Offline Paul1453

  • Level 3
  • ***
  • Posts: 1085
  • I love Tube amps
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #3 on: June 09, 2016, 10:47:49 pm »
So you guys don't like the old domino silver mica caps?

I watched a youtube video by mrcarlsonslab (I think),

explaining some of the tolerances of the different caps.

He hated all paper caps, said to remove them all.

Some of the other newer material caps were quite temperature sensitive.

I thought he indicated the old silver mica caps were very temperature stable, and unlikely to leak.

I haven't had any problems with them since I began using them when I got my cheap capacitance testing meter.

Offline markmalin

  • Level 3
  • ***
  • Posts: 827
  • Malin Sweet Loraine
    • Malin Amplification
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #4 on: June 09, 2016, 10:55:06 pm »
do you buy the NPO ceramics from Digikey? I  see Doug doesn't have them, and I don't see them at CE Dist or Mojotone. 
"... there are Flying V's and then there are the ones shaped like peanuts..."  - my son at age 9

Offline PRR

  • Level 5
  • *******
  • Posts: 17082
  • Maine USA
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #5 on: June 09, 2016, 11:07:58 pm »
I would use the 500V Silver Mica.

I like the way they look.

I really think there are more productive places to stir the spice.

Offline markmalin

  • Level 3
  • ***
  • Posts: 827
  • Malin Sweet Loraine
    • Malin Amplification
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #6 on: June 10, 2016, 07:50:48 am »
That's what I have in there, but here's what's driving this.  I'm trying to track down a very intermittent situation where the amp start producing static (popping, sounds like an old radio off station) for maybe 2 minutes and then stops.  I was spraying some freeze spray around to see if maybe it was a cold solder joint and when I hit the bright cap (120pf silver mica) it caused the amp to rumble and pop.  Maybe normal, but I swapped it with a ceramic I had and it's not as prevalent ...which may be my own idiotic lack of experience...but I hit the mica treble cap and that made the same sound only worse. Hence the idea to swap it out.


Thing is, I'm not sure I like the sound of that particular bright cap


that's the whole story
"... there are Flying V's and then there are the ones shaped like peanuts..."  - my son at age 9

Offline Ed_Chambley

  • Level 4
  • *****
  • Posts: 3785
  • Nothing is too old.
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #7 on: June 10, 2016, 08:43:24 am »
Here is a Mouser link to the Ceramics I use. http://www.mouser.com/Passive-Components/Capacitors/_/N-5g7r?P=1z0z7l5&Keyword=npo&FS=True


I ran into some problems with Silver Mica caps, However the black ones Doug has are good.


I have read where guys day you must use Silver Mica or you amp will sound harsh and the same person covets a 65 Stock Fender Deluxe. :l2:

Offline markmalin

  • Level 3
  • ***
  • Posts: 827
  • Malin Sweet Loraine
    • Malin Amplification
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #8 on: June 10, 2016, 09:34:51 am »
Thanks, Ed.  That helps.  I may just order a handfull of these and see if I notice any difference.


I have noticed changing ceramics for silver mica has mellowed out a 5E3 build I had, but this particular amp is so bright, so harsh and so hissy if I turn it up loud.
Anyhow, thanks - I'm going to try the NPO's


I'm curious to know more about the issues you had. Was it similar static?  Here's the thread to my original issue (not to hijack this one).  http://el34world.com/Forum/index.php?topic=20385.msg214615#msg214615
"... there are Flying V's and then there are the ones shaped like peanuts..."  - my son at age 9

Offline Ed_Chambley

  • Level 4
  • *****
  • Posts: 3785
  • Nothing is too old.
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #9 on: June 10, 2016, 12:06:12 pm »
Thanks, Ed.  That helps.  I may just order a handfull of these and see if I notice any difference.


I have noticed changing ceramics for silver mica has mellowed out a 5E3 build I had, but this particular amp is so bright, so harsh and so hissy if I turn it up loud.
Anyhow, thanks - I'm going to try the NPO's


I'm curious to know more about the issues you had. Was it similar static?  Here's the thread to my original issue (not to hijack this one).  http://el34world.com/Forum/index.php?topic=20385.msg214615#msg214615
No, not chasing noise.  I will use silver mica, but I buy Cornell From Mouser.  When I am building a clone circuit, I use what was used in the real amp.  Like My AC15, I could not get the exact ones, but I used ceramic.


They are not as heat sensitive to the soldering iron.  I can't hear the difference and even for snubbers I prefer ceramic.  Tougher and durable and easy to get in high voltages.


A few years back I read an article on how much better Silver Mica sound and I fell for it and bought a lot of them from Weber.  Big mistake.  They leaked DC and I did not have near the troubleshooting experience then as I do now.  Needless to say I kept getting problems.  I will say I learned a lot, but the frustration level was high.


I finally realized that all the old amps I have that everyone loves like my 68 Plexi, 65 Deluxe, 62 Bassman.............etc all have ceramic caps in them.  I also spent some time studying the caps and there are plenty of ceramics that are audio quality and they are normally cheaper.


I only use Silver Mica if I am replacing one for someone else.  Also, I use a lot of Sozo caps because I get them free. :icon_biggrin:


I have pretty good ears too.

Offline jjasilli

  • Level 5
  • *******
  • Posts: 6731
  • Took the power supply test. . . got a B+
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #10 on: June 10, 2016, 06:36:05 pm »
Angela says the old ceramic caps sound better than new production.

Offline Ed_Chambley

  • Level 4
  • *****
  • Posts: 3785
  • Nothing is too old.
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #11 on: June 21, 2016, 02:36:01 pm »
Angela says the old ceramic caps sound better than new production.
Who is Angela and why should we listen to her? :laugh:

Offline sluckey

  • Level 5
  • *******
  • Posts: 5075
    • Sluckey Amps
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #12 on: June 21, 2016, 02:45:51 pm »
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline FranciscoPerez

  • Level 2
  • **
  • Posts: 189
    • 22 nanofarads
Hoffman Amps Forum image
Re: Silver Mica vs Ceramic caps for treble?
« Reply #13 on: June 21, 2016, 03:15:33 pm »

I usually use a mix of polystyrene and C0G ceramics. Had a bad experience with some silver mica caps, which turned out to be microphonic, and stopped using them.


Distortion generated by old ceramic caps in an RC filter is severe compared with C0G, and things in an CR filter are much worse, in the neighbourhood of 1% at low frequencies
You might like this distortion for guitar, though.  :dontknow:

 


Choose a link from the
Hoffman Amplifiers parts catalog
Mobile Device
Catalog Link
Yard Sale
Discontinued
Misc. Hardware
What's New Board Building
 Parts
Amp trim
Handles
Lamps
Diodes
Hoffman Turret
 Boards
Channel
Switching
Resistors Fender Eyelet
 Boards
Screws/Nuts
Washers
Jacks/Plugs
Connectors
Misc Eyelet
Boards
Tools
Capacitors Custom Boards
Tubes
Valves
Pots
Knobs
Fuses/Cords Chassis
Tube
Sockets
Switches Wire
Cable


Handy Links
Tube Amp Library
Tube Amp
Schematics library
Design a custom Eyelet or
Turret Board
DIY Layout Creator
File analyzer program
DIY Layout Creator
File library
Transformer Wiring
Diagrams
Hoffmanamps
Facebook page
Hoffman Amplifiers
Discount Program


password