Tone pot 500pf silver mica capacitor connection to vol pot on 18 watt lite vs 5e3

[Guy77]

Does anyone know why the 500 pf silver mica coming from tone pot on 18 watt lite connects to far right of vol pot ( connection on vol pot that goes to capacitor on circuit board of amp) but on 5e3 same 500pf connects from tone pot connects to middle connection of the volume pot ?

[printer2]

The 5E3 uses an old Fender volume control arrangement where the signal goes into the wiper of the pot and comes out of the top terminal. A more standard way of using the pot is as a voltage divider, where the signal comes into the top of the pot and the signal leaves out of the wiper. This is how the 6G3 Deluxe is set up. I used a four pole switch to change from the 5E3 circuit to the 6G3 circuit in the amp I am building now.



The switches are in 6G3 position and when switched they are in 5E3 mode. The 18 Watt uses the pots in a voltage divider arrangement.

[Guy77]

Thank you for the explanation! That was great . I finished building a smokin joe II amp and I am changing the cascode preamp to a parallel one and I am debating whether I will leave the vol pots as they are (old fender style) or change to the 18 watt style. At least I now know that both ways are correct and it's more a matter of taste!

[printer2]

I originally wanted to put a 5E3-6G3 switch on the amp, may have left it that way but I also threw in a BT tone stack. I decided to keep it simple and kept the 6G3 and BT tone stack. While the 5E3 was interesting I decided to go for the more consistent response of the voltage divider arrangement.

[Guy77]

I originally wanted to put a 5E3-6G3 switch on the amp, may have left it that way but I also threw in a BT tone stack. I decided to keep it simple and kept the 6G3 and BT tone stack. While the 5E3 was interesting I decided to go for the more consistent response of the voltage divider arrangement.

Yes i think I would like to add a BT tone stack to my smokin joe II as well. I switched it to a parallel preamp and I like it better a certain volume levels. I will install a switch to switch between the cascode preamp and the parallel one. I think I will also try to find a way to switch between running a simple tone knob to a treble bass stack that way both options are available!

[printer2]

Yes i think I would like to add a BT tone stack to my smokin joe II as well. I switched it to a parallel preamp and I like it better this way. I think I will try to find a way to switch between running a simple tone knob to a treble bass stack that way both options are available!

Well you are talking to the right person. I did the Tweed/BT tone stack on my last amp. You need a three pole switch, I used a four pole as I switched the cathode bypass cap also.



The treble control turns into the tone knob. You could do it with separate controls and just switch between them, I wanted one less knob. In my latest amp I am using separate controls and running the triodes in parallel for the Tweed control and in series when using the BT stack.

[Guy77]

Very nice! Great work. Looks like I will be busy for the next while! I switched the vol tone connection back between the old 5e3 style and the newer 18 watt style and I now know why wanted to switch between the 2 styles there is a lot of tonal differences between the too!! I can't decide witch I like better !!!

[printer2]

Very nice! Great work. Looks like I will be busy for the next while! I switched the vol tone connection back between the old 5e3 style and the newer 18 watt style and I now know why wanted to switch between the 2 styles there is a lot of tonal differences between the too!! I can't decide witch I like better !!!

I spent a few days switching between the two deciding which I liked better. I also had a switch that selected from one channel or the other or both, so I could do a quick change and still remember what the other sound sounded like. I will probably make an amp later with just the 5E3 with the volume/tone switch.