5E3 bridging input jacks with switches

[M Fowler]

Got some chassis that have 1/4" mini toggle switch holes on faceplate of chassis and I don't know what the originator of the chassis intended to use the switches for.

I was thinking about using them to bridge CH. 1 high into CH. 2 low
and CH. 1 high into CH. 2 high etc.

What else besides bright or boost would switches be used for on the 5E3 any ideas?

Mark

[EtherealWidow]

Are they just SPST?

Could use it to adjust the bias on V1. For example, two 1k5 resistors in parallel for a total Rk of 820 ish, then take one out and the stage is center-biased to 1k5 or whatever.

Could also implement some NFB and then use the switch to toggle NFB in and out.

Could also toggle weird things out with the power tube cathode. For example, different equivalent Rk, different equivalent Ck (for partial bypass), no Ck at all, whatever.

Being that I own a Mesa Boogie and am still new to the amp building game I have this horrible impulse to want to toggle everything in and out of a circuit.

[M Fowler]

I edited my OP to show the switches are on the faceplate of the chassis so at first I was assuming bright switch or boost but thought how boring.

So then I thought about using them for jumpering the input jacks.

I had played through a Louis Electric KR amp one day and on that fantastic sounding amp you plug into the four different jacks with each one having a different gain to the circuit.

[Firestorm]

I had played through a Louis Electric KR amp one day and on that fantastic sounding amp you plug into the four different jacks with each one having a different gain to the circuit.

How would you wire that? On the 5E3, plugging into four input jacks just makes them all "high." One channel bright, the other normal.

What would bridging the inputs sound like? Considering the volume pot interaction.

[M Fowler]

No you choose a single jack to plug into but each one brings on a different gain.

The KR looked to me to be Marshall JCM type with EL34's and Celestion Vintage 30 speaker.

[Firestorm]

No you choose a single jack to plug into but each one brings on a different gain.

The KR looked to me to be Marshall JCM type with EL34's and Celestion Vintage 30 speaker.

Maybe like a Tweed Vibrolux with four inputs.

[dorrisant]

Rotary switch with different values for the input resistor? Nopey, that won't get you two channels. Unless... Double pole rotary maybe?

Maybe two separate switches?

I would love to do something like that with the one I just built. I haven't put a faceplate on yet.

Mark, did you find any schems on it?

I'll look look around...

Tony

[pops]

You can bridge so one input goes thru both channels. Really cool sound not twice as loud, but much more intense.

[M Fowler]

I'll just use a mini toggle switch that will bridge 1 high with 2 low.

As well as mini toggle switch to bridge 1 high with 2 high.

The holes are already drilled in the chassis and I have a draw full of mini switches so why not use them instead of a simple jumper cable, right.

[dorrisant]

Someone on TGP had mentioned bridging the two inputs close to the tube socket with a relay and switch... Then a bright/normal switch at the jacks. I don't think that this would cover all of the possible bridging combinations though.

I kinda like the idea of two inputs. Run straight into one channel and delayed into the other.

Damn, Leo was a genius!

Where's my drill?

Tony

[M Fowler]

On my Swamper model I have one input jack/1m but high volume and low volume so you can mix them, the rest of the amp is 5F6A but with MV.

[Gordie]

Right now, I'm shoehorning a 6G3 circuit into "FrankenGarnet". Weber's "Lenore" 6G3 kit has bridging on the inputs with a slider switch. Check it out on Weber's kit pages....