Can you jumper the inputs on a Tweedle-Dee?

[dannieh42]

If you are plugged into the normal-high input can you jumper the normal-low to bright-high input? I read somewhere (even though I can't find it now) that the mods to this amp removed the interaction between the channels. Is that true?

I tried jumping the inputs, and amp made a squealing sound similar to microphone feedback (as opposed to normal distorted guitar feedback). It wasn't very loud, but I immediately knew it was not good. I have a master volume installed in the hole usually occupied by the bright-low input. The jumper I used was a patch cable with 90 deg. ends. and the case of one of the ends was touching he shaft of the Master volume pot. Could this have cause the squeal? If I experiment with this further will it damage anything?

[pompeiisneaks]

I think it may depend on the setup, but normally when you bring two channels together they have two 'mixing resistors' 220k or 100k is what I've seen in the past. This helps make sure they can't create feedback loops. This amp, if both volumes are high enough would cause that problem for sure, as there's only a mixer resistor equal to the value left in the volume pot between input and wiper on either side. I also think the tone pot works on both channels, but slightly differently on each. Either way, there would definitely need to be some modification done to allow jumping the channels. The squealing you mention is the typical sound you get with positive feedback and oscillation. Another bad jumping method is when you have inverted signals and you end up with signal being weakened or muted entirely depending on how differing the channels are tonally.

~Phil

[PaisleyTube]

There's less interaction compared to a stock 5E3.

Jumpering ain't no problem (no phase issues for example) but you'll get a lower input-impedance and the amount of bass is already enough.

Just give it a try and see if you like it!

[PaisleyTube]

the problems are probably due to layout-problems, move the MV further away from inputs/preamp

[dannieh42]

the amount of bass is already enough.

That's no kidding. If jumper will give more bass, then I won't be doing it. I keep the tone on the amp pegged and would even like a little more. I like the way my Tele cuts through. I don't want to tame it too much. I've heard people talking about getting rid of those "ice pick" highs...I don't want it to be an ice pick, but I would at least like it to be a really sharp stick LOL

[67plexi]

I built my Tweedle-Dee Deluxe's with 4 inputs. And the other D Deluxe's I'm aware of have 4 inputs. They jumper just fine.

[pompeiisneaks]

well then I stand corrected!

~Phil

[rogb]

I built my Tweedle Dee as per TAG info (Thanks guys!)
I didn't much care for the 6V6 thing so converted to 6L6 and 35w iron. Everything else is the same apart from RobRob 3 way NFB switch.
It jumpers just fine, in fact that is how I use it all the time.