Built my first 5E3! Comments/questions

[mbratch]

Depends on the quality of the pots you have. A lot of modern production audio pots are cheaply made with two bits of carbon, and have a 'two-line' taper instead of a log taper. They are susceptible to funny bumps. Best thing would be good quality NOS 1MA pots if you can find some.

Thanks for the suggestion tubeswell. I double checked and I have CTS 1MA pots. They're probably a good quality by today's standards but, as you say, pots are on the cheap these days. I'll keep my eyes open for NOS. 8^)

[Five_E35]

Any idea where I can get these? I checked Mouser but couldn't find them there. I did a quick Google troll and didn't come up with something, but I could dig further. Wondering if others here have used them and know of a good supplier.

The last Peaveys and early 90s Fenders with working ground switches used a .01uF cap. Mouser has them, try searching X1 Y2 Suppresion Capacitors or try Mouser Part # 81-DE2F3KH103M

Most people convert the ground switch into a far more usefull standby switch. With a 3 prong plug the ground cap amounts to a poor mans EMI/RFI filter. The newest Fenders have a .1uF cap hot to neutral, probably to meet the new EMI/RFI standards. Mouser also has IEC power inlets with more extensive filtering. Maybe someone familiar with the standards can comment on whether any of this is worth adding to home builds, or just puts more noise on the chassis.

[mbratch]

The last Peaveys and early 90s Fenders with working ground switches used a .01uF cap. Mouser has them, try searching X1 Y2 Suppresion Capacitors or try Mouser Part # 81-DE2F3KH103M

Most people convert the ground switch into a far more usefull standby switch. With a 3 prong plug the ground cap amounts to a poor mans EMI/RFI filter. The newest Fenders have a .1uF cap hot to neutral, probably to meet the new EMI/RFI standards. Mouser also has IEC power inlets with more extensive filtering. Maybe someone familiar with the standards can comment on whether any of this is worth adding to home builds, or just puts more noise on the chassis.

Thanks. I had done a search at mouser.com before with "x1" and something else and it got nothing. Not sure what I did wrong there. But the part number you gave took me right there, so that's cool. So a .01uF is OK in place of .05uF in that spot?

Regarding standby conversion, I may do that. I said in a prior post that I'm a little anal about the amp in that it says "ground" on the silk screen of the chassis, so I was going to (for now at least) leave it as a ground understanding that a standby isn't functionally necessary for an amp of this design. I use a SF Princeton Reverb which also does not have a standby and I have never missed it. I just turn the volume down on my guitar when I'm not using it. On that amp, I always leave the ground switch in the center position.

Ultimately, I'll probably wire the 5e3 ground as a standby or something else.

[hasserl]

The taper of modern pots is different than it was in the pots made back when 5E3's were new, so the reaction you are getting is common. Also, because of the design of the 5E3 Volume control where the input to the pot is the wiper, this adds to the action you describe, and the 1M value adds to it. Use a 500k audio taper pot to reduce this somewhat, but it is more lossy (loads down the input gain stage). A 250k pot will reduce the effect even more, but is more lossy still.

Change the wiring so that the input to the Vol pot is at the top of the pot and the output is the wiper, as in most other Fender amp designs, and you'll get better control action of the pot. I.e. the volume will increase over a greater swept area of the pot travel. But it won't be a straight 5E3 anymore, and you'll loose the interaction of the two Volume controls.