18 watt modern classic hypothesis

[Bieworm]

Josh,

Hypothetically...

What if I disconnect the jumper wire between pin 2 and 7 of V1.. And put that jumper wire between pin7 V1 and pin 2 V2. Would I fatten the sound on the trem channel like it does now on the normal channel? I just really like the fatness of the normal channel and wonder if it's transferable

[JMPGuitars]

Josh,

Hypothetically...

What if I disconnect the jumper wire between pin 2 and 7 of V1.. And put that jumper wire between pin7 V1 and pin 2 V2. Would I fatten the sound on the trem channel like it does now on the normal channel? I just really like the fatness of the normal channel and wonder if it's transferable

What do you think that would do? Pin 2 and 7 on the preamp tubes are the grids. The grids are like the tube inputs. 12AX7/ECC83 are "dual triodes" - that's like 2 tubes in 1. Running a dual triode in parallel usually does give a fatter sound, because both halves of the tube are pushing the same input signal to the next stage. But if you took the input wire from one tube, and instead connected that wire to another tube (that uses the other half of the PI), how would that benefit you? Or how might it change the sound?

Take a look at the schematic to try and get a better idea of how the signal passes through the amp from the input jack to the OT. Can you see how it goes from stage to stage?

Besides that, you have to be careful modifying the tremolo channel. If you mod it the wrong way, you'll kill the trem function.

EDIT: download the schematic again if you already had it. There was an annoying Visio glitch in it.

[zaphod_phil]

Just replace the 0.005uF coupling cap going to the Trem Channel volume pot, with a 0.01 or 0.022uF. That will nicely thicken up the Trem chanel's tone, without any risk to tremolo operation.

[Bieworm]

I already did that. And it indeed gave more low.
But I tried a G12H30 instead of the 2x10 1028K speakers. Wow what a dif!!! The G12 was way more bass...

[zaphod_phil]

I have a 1970s G12H30. It's a fantastic sounding speaker!

[JMPGuitars]

I already did that. And it indeed gave more low.
But I tried a G12H30 instead of the 2x10 1028K speakers. Wow what a dif!!! The G12 was way more bass...

Build yourself a vertical 2x12 cabinet, and put in just the one G12. I think you'll like it even more.

[bvayling]

Building a 2x12 vertical stack for the JTM45. Could always use it for the 18. Endless variations!