The adventure time tube amp- Did any catch it?

[JZatopa]

I'm not sure if anyone here watches Adventure Time or their kids watch it but this last episode had something cool in it. It looks to be a PP guitar amp to me. I thought I would post it for you guys to check out. Does anyone recognize the circuit?

 

[DeathRex]

Finn needs Princess' help.

 

[overtheairbroadcast]

My guess is this low power 6L6 phase inverter guitar amplifier.

http://www.ampbooks.com/home/amp-technology/6L6-phase-inverter/6L6-phase-inverter-amp.gif

But it is just a guess...

 

[JZatopa]

My guess is this low power 6L6 phase inverter guitar amplifier.

http://www.ampbooks.com/home/amp-technology/6L6-phase-inverter/6L6-phase-inverter-amp.gif

But it is just a guess...

That looks like it's it to me.

 

[overtheairbroadcast]

Wonder what this would sound like as a regular monoblock amplifier... Looks straightforward enough to try, but not sure what it might be missing in terms of tonal range and inputs (that skill level is way beyond my scope).

 

[TheGimp]

IN the first screenshot it is interesting to note the number of tubes. six orange ones in the lower rt corner, and several blue ones all over.

Kind of low B+.

EF86 screen voltages look reasonable so if you up the B+ you will have to change the screen resistor values.

Scratch the tone circuit.

personally, I'd change the two first tubes to 6AU6s, but that's because I have a bunch.


Oh! I just noticed the cathode voltage and cathode resistor. That 5.6K 5W resistor has to be changed or eliminated and the 200R resistor changed.

 

[cnpope]

Pi is wrong in the 8th decimal place in the second screenshot.

Chris

 

[TheGimp]

That schematic looks like a variant of the amp in the N709 datasheet.

Then again there are probably quite a few EL84 amp schematics with two EF86 stages.

Pi error... Calculator error on a cheap calculator?

 

[Merlinb]

I believe these are the droids you are looking for:
http://www.ampbooks.com/home/amp-technology/6L6-phase-inverter/6L6-phase-inverter-amp.gif

An externally hosted image should be here but it was not working when we last tested it.

 

[TheGimp]

Interesting design approach.

 

[stephen_keller]

Kind of low B+.

The B+ pretty much has to be kept that low, if one intends to combine phase-inversion with power amplification, doesn't it?

Stph

 

[Richard Ellis]

On the second screen-shot there is some non-sense symbols in the front-end of the PS...& some out of place connections.


__________________________________________________Rick..........

 

[TheGimp]

The B+ pretty much has to be kept that low, if one intends to combine phase-inversion with power amplification, doesn't it?

Stph

Not really. The Odd-Watt uses this topology with KT88s.

The earliest article I've seen was "COMPACT HI-FI POWER AMPLIFIER" By Melvin Leibowitz.

Compact 6 Watt Amplifier

I would be surprised it there were not other references that pre-date it.

It really is nothing more than an LTP using output tubes. The large tail resistor helps hold down distortion.

I didn't recognize it at first as I think of low power in the 1-3W range and I now believe this design is aimed at subWatt output.