5E3 w/ DC at input jack

[JazzGuitarGimp]

HA! I'm in the middle of a build in which I used a generic fiber board from Weber. I've seen this type of board in internet pictures of the insides of a Divided By 13 FTR37 amp. I don't know if DB13 is buying from Weber, but I looked high and low, and that's the only vendor I could find that has it. But it too, is conductive. So I am in the middle of doing a layout for a new board.

[xtian]

Well, that sucks. Can you tell it's conductive with a multimeter, or only at high voltage?

[Leo_Gnardo]

I don't know if DB13 is buying from Weber, but I looked high and low, and that's the only vendor I could find that has it. But it too, is conductive.

I believe Mojo also supplies their kits with - conductive - black fiber board. A couple smaller outfits too.

If I could have a dollar for each hour I've spent warning people away from this stuff . . . could buy a month's groceries.

Got a customer who wants a custom amp built into a 5F11 Vibrolux chassis/box, I already warned him away from the board. I won't build on that stuff, period. Got lots other better things to waste time on.

Doug Hoffman's always been good about making turret boards & providing parts to make your own on glass/epoxy.

[JazzGuitarGimp]

Well, that sucks. Can you tell it's conductive with a multimeter, or only at high voltage?

Hi Aaron,

I had assumed you were asking this of the OP, but just in case you were asking me: Using my DMM with a 100K load across the probes, I can measure DC voltages to GND at unused eyelets. To be clear, this is a generic eyelet board, with rows of pre-installed eyelets. And yes, it sucks. But to the positive side, it has forced me into doing a pcb layout for the amp - and now I will get to incorporate all of the ancillary circuits I wanted to experiment with, such as AB2 MOSFET drivers and A/B/Y relay channel selection.

[Charlie Wilson]

OK at the risk of getting pounced on, here is my .02. I have this Pro Reverb that I have owned for over 20 years and done thousands of gigs with. A few years ago it started to sound bad, dull and lifeless. I checked everything component and connection in the amp and even swapped out transformers and it still sounded bad. Just by chance I read an article on conductive fiberboards and checked mine and there was voltage on the board. I purchased a Torres phenolic blackface reverb board and swapped it out for the original board in my amp. Well the amp was clear again and no more weird sounds but after a few gigs I decided that I hated the sound of the amp with the new board. The high end was hard and plastic sounding and the amp had no give to it. So I bought a fiberboard blank from Weber and copied my original board put it in and my amp sounded great. Like it did originally. Since then I have built dozens of Fender reproductions and have had no issues with fiberboard and all of the amps sound great. Now I am not saying that I don't see a tad amount of voltage on the boards or that they are ideal electronically but they sound right for vintage Fender style amps and to my ears fiberglass or phenolic does not. OK let the pouncing begin.
CW

[Charlie Wilson]

If I may add one more thing, the worst fiberboards for conductivity in old Fenders are the ones that have been waxed. I don't know what goes on with those things, maybe the wax traps moisture or dirt but those things are a nightmare. Also, old fiberboards that have been heavily worked on. Maybe the flux soaks into to the board and contaminates it. My Pro Reverb had been worked on many times by various repairmen(including Fred Tacome) before I started repairing and building amps.
CW

[JazzGuitarGimp]

Fred is a great guy. He did some work for me as well, also before I started working on my own stuff.

[JazzGuitarGimp]

but after a few gigs I decided that I hated the sound of the amp with the new board.

I've been wondering about that. Been thinking, "what if the co-mingling of signals has a positive affect on the sound of the amp"? I guess I won't know until I try it for myself.

[The Ballzz]

but after a few gigs I decided that I hated the sound of the amp with the new board.

I've been wondering about that. Been thinking, "what if the co-mingling of signals has a positive affect on the sound of the amp"? I guess I won't know until I try it for myself.

Well Sir,
I've seen this discussed several times on other forums. The general consensus "IS" that it indeed can have an effect, but being able to quantify, qualify and figure it into design calculations in a useful manner would likely be much like "herding" cats!
Just My $.02,
Gene