6sj7 tone control quest

[andrew]

I would like to run a 6sj7, volume, then a tone control into a paraphase PI. What tone control would be effective. Thanks!

[Alexo]

No expert here, but the SJ7 being a pentode will have a pretty high impedance output, like an EF86. You could do something similar to what a lot of folks do with EF86's - a cap selector switch (rotary 6 way) for a tone control, followed by a volume control. Works surprisingly well.

[UR12]

I would like to run a 6sj7, volume, then a tone control into a paraphase PI. What tone control would be effective. Thanks!

Just my 2 cents but I wouldn't put the Vol control right before the tone stack. I would put it before the pentode or after the stack. I would go with a baxandall but that is more of a personal choice than a technical choice. Why are you wanting to go with the paraphase?

[andrew]

I haven't had any experience with one but I've read they distort nicely. Thank you for the advise guys!.

[klingo]

Hello,

IMHO, this one (schem) work nicely with an 2M5/ra EF86, so it may work with a 1M/ra 6SJ7.
never tried the cap switch/cut control device, but most of the time less components = better tone.

[andrew]

Thanks KLINGO! It shall be tried.

[jimipage]

for some reason I'm not able to view the attachment


(edit: problem was on my end -- solved )

[Andy Le Blanc]

I've wired a 50w with a paraphrase....it will have a much dirtier tone with less head room...but you will get a nice harmonic distortion with good tone color...the pentode pre will have a lots of gain potentialy.....try a simple treble bleed with .01 cap and 500k or 250k pot. first....it can be applied before or after the invertor....some old amps used zero bias and had the tone and vol. wired in front of the pre....

[andrew]

I used the tone control schematic KLINGO provided and it worked great. I decided not to use a paraphase and used a LTP. It sounds really good but I would like to know if another style of power supply would be better suited for a 6SJ7-12ax7 PI with two 6v6? My power supply lineup is a 135ohm choke-5K and a 1.5K (20 watt PP from the AX84 site) and a 275-0-275v 150ma transformer. Thanks again!

[Johnhenry]

Look at the early Ampeg's, simple tone stack, just a tone control and vol. straight into the P/I, a TMB or Bax Stack will suck a lotta tone and gain, you can make it back up by adding more pre/amp tube's but simple can sound so sweet.
Johnhenry

[Andy Le Blanc]

I have a Gretch on my bench that has tone control you might like.

Its a G-6162 and a schematic can be found under bargain bin at schematic heaven.... Dual twin reverb...

on paper it looks weird... its a phase angle thing similar to the tone control
used in a big muff....

its very useable for a one knob affair..(no puns please)