FET or Bright relay?

[mlp-mx6]

So, do I install the FET board (and input) that I'll likely never use, or do I use that space for the "bright only on clean" relay that I'm sure I need?

How much use do you give the FET input? I *really* feel the need to turn off bright in OD, but have it on for clean. Can anyone make a compelling case for the FET input?

I already have 3 relays (mid-boost is footswitchable), so I don't have a ton of room along the circuit board front edge. The side wall where I would mount the FET board looks like an ideal location for mounting a relay instead.

[talbany]

Here is an idea I did on 1 where I didn't have the room for another relay to mount to the chassis..I made the relay board for the bright big enough to sit on top of the 2 existing relays and used a little hot glue right on the top of the relays themselves and glued the board right to the top of them.. Hot glue works best in case you need to remove it to replace a relay you can work it loose but otherwise holds fine.. This may not work for yours but just a thought...

Tony

[tubedogsmith]

Maybe just put a bigger bright cap on the master and use a treble bleed on the OD section.

[Guitarman18]

Tony wrote:

Here is an idea I did on 1 where I didn't have the room for another relay to mount to the chassis..I made the relay board for the bright big enough to sit on top of the 2 existing relays and used a little hot glue right on the top of the relays themselves and glued the board right to the top of them.. Hot glue works best in case you need to remove it to replace a relay you can work it loose but otherwise holds fine.. This may not work for yours but just a thought...

Tony

That's a great idea Tony, but IME hot glue seems to eventually comes adrift, so for added security I'd add some cable ties for support. Keep the glue to prevent vibration.

Cheers,

Paul.

[mlp-mx6]

Maybe just put a bigger bright cap on the master and use a treble bleed on the OD section.

I have a treble bleed on an earlier ODS build, but I'd like to build one that sounds "right" without it. I've never seen the circuit in an actual Dumble, so it *must* be possible. (I know, the "switch off the bright" isn't in an actual Dumble either.) I also think that the bleed circuit loses something in the vocal quality.

I also expect the amp to open up and smooth out a bit as I continue to play it. Still, I much prefer the OD tone with bright off.

Still looking for an FET champion. Anyone?

[markr14850]

Still looking for an FET champion. Anyone?

I found the stock FET circuit to be a bit shrill, jangly, and hissy. I made a few simple tweaks, and now I like it.

I use it for single coils. Humbuckers go into the normal input. I adjust the FET output trimmer to make the two ways roughly match.

Details here: https://tubeamparchive.com/viewtopic.php?t=9561

--Mark

[Structo]

You could use longer screws and another pair of standoffs and piggy back the relay on top the other.

I tried the treble bleed as well and didn't like it.
What has improved my amp over everything I have tried is by adding the Dumbleator to the mix.

I have a 47pf bright cap on the master and it seems about right for my amp and speakers.
I also changed the .001uF bright cap on the D'lator to a 330pf as well as the other bright cap, both at 330pf.
I have 330pf snubbers on V2 as well.

[talbany]

Tony wrote:

Here is an idea I did on 1 where I didn't have the room for another relay to mount to the chassis..I made the relay board for the bright big enough to sit on top of the 2 existing relays and used a little hot glue right on the top of the relays themselves and glued the board right to the top of them.. Hot glue works best in case you need to remove it to replace a relay you can work it loose but otherwise holds fine.. This may not work for yours but just a thought...

Tony

That's a great idea Tony, but IME hot glue seems to eventually comes adrift, so for added security I'd add some cable ties for support. Keep the glue to prevent vibration.

Cheers,

Paul.

Paul
Good Idea..