What to do with Magnavox 6v6 amp?

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sluckey
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Re: What to do with Magnavox 6v6 amp?

Post by sluckey »

How would I use that circuit with only one input jack?
Just remove the top jack and it's 1M resistor. Connect pin 2 to pin 7 directly on the tube socket. The "parallel" jack becomes your single jack.
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Kagliostro
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Re: What to do with Magnavox 6v6 amp?

Post by Kagliostro »

Based on the 5F2 this will be a start point, then I think you must tweak R1 - R2 - C2 (may be only C2)

EDIT: The schematic is missing of the plate resistor and PS connection of V1b - see further post
Image

the same way is to do with the 18W preamp

Franco
Last edited by Kagliostro on Sun Mar 26, 2017 10:38 pm, edited 1 time in total.
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didit
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Re: What to do with Magnavox 6v6 amp?

Post by didit »

Advice so far spot on. Particularly mid-50s Gibson. Be prepared for fairly clean low gain tone. One small thought is a sub-mini pentode. There is at least one equivalent to 6AK5, perhaps slightly lower dissipation. That shouldn't matter. Less microphonic and could perhaps fit a socket where the RCA input jack is now.
nsmith01tx
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Re: What to do with Magnavox 6v6 amp?

Post by nsmith01tx »

BTW, have you an ef86 ?
No, no ef86 / 6267.
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Re: What to do with Magnavox 6v6 amp?

Post by nsmith01tx »

Kagliostro wrote: Sat Mar 25, 2017 11:41 pm Based on the 5F2 this will be a start point, then I think you must tweak R1 - R2 - C2 (may be only C2)
Thanks Franco, this looks good.
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Kagliostro
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Re: What to do with Magnavox 6v6 amp?

Post by Kagliostro »

If you want use only an input jack

Oh, I forgot, is good practice to replace the old electrolitic caps, they are source for problems

EDIT, Stop ALL, I forgot the second triode plate resistor and supply connection

Franco
Last edited by Kagliostro on Sun Mar 26, 2017 10:39 pm, edited 1 time in total.
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Kagliostro
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Re: What to do with Magnavox 6v6 amp?

Post by Kagliostro »

I apologize

Here is the corrected schematic

Image

Franco

p.s.: No 6SJ7 tubes on stock ??
nsmith01tx
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Re: What to do with Magnavox 6v6 amp?

Post by nsmith01tx »

Kagliostro wrote: Sun Mar 26, 2017 10:36 pm p.s.: No 6SJ7 tubes on stock ??
Thanks Franco, sorry work got in the way this week.

No 6Sj7 either, besides 12AX7's I have these:
  • 12BH7A - Noval (similar or equiv: CV5042)
  • 6973 - Noval (similar or equiv: 6CZ5)
  • 6CB6A - 7-pin (similar or equiv: CV8926, EF190)
  • 6DJ8 - Noval (similar or equiv: 6N23P, CV5358, ECC88)
None of which look equivalent to what you've suggested.
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didit
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Re: What to do with Magnavox 6v6 amp?

Post by didit »

nsmith01tx wrote: Fri Mar 31, 2017 5:50 pm
Kagliostro wrote: Sun Mar 26, 2017 10:36 pm p.s.: No 6SJ7 tubes on stock ??
  • 6CB6A - 7-pin (similar or equiv: CV8926, EF190)
None of which look equivalent to what you've suggested.
Might be workable. Small signal pentode with similar basing to 6AK5. Different specs. Potentially microphonic. Need to work through biasing detail. Adventure. Perhaps better to spend a bit for a well known quantity. Sleeve of 5x 6AK5 should be <$30 with shipping.

Best .. Ian
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Kagliostro
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Re: What to do with Magnavox 6v6 amp?

Post by Kagliostro »

If you haven't a known usable pentode, go with a 12ax7

search a circuit of your interest that uses only one tube

for space reasons (you have seen there are many possibilities) and build it

Franco
stephenl
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Re: What to do with Magnavox 6v6 amp?

Post by stephenl »

6U8a triode/pentodes are plentiful and cheap. The triod could be used to drive the pentode or as a cathode follower. It's a nice sounding tube, similar to 7199 with different pinout.

Jaff Woolsey at Sonic Dude Ranch has an input jack mounted LND150 circuit board preamp that is very transparent, if you don't mind a little sand in your box.http://sonicduderanch.com/products/jack-boost
Steve
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Kagliostro
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Re: What to do with Magnavox 6v6 amp?

Post by Kagliostro »

6N2P is the cheap russian version of the 12ax7 (european ECC83)

you can find on the cheap also the 6n2p-EV (or EB, is the same) they are strong long life military versions

the only bad thing is they are only 6.3v heater, no 12.6v heater connection

Image

the good thing is that pin 9 is connected to an internal shield between the two triodes and you can

find it useful in some projects

http://tubes-store.com/advanced_search_ ... words=6n2p

Franco
nsmith01tx
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Re: What to do with Magnavox 6v6 amp?

Post by nsmith01tx »

Sorry for the long delay on this ... working on a 5e3 clone now. I'll get back to this as soon as I have that together.
Again, thanks for all the help.
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