ODRS #13 Layout & Schematic

[M Fowler]

Nice I'll be waiting for an updated layout/schematic Aaron

Wish I could contribute but have nothing to offer.

[amplifiednation]

...

[bcmatt]

No, the reverb wet signal is split off the clean channel (at the parallel gain stage around V1b there is a jumper at the grids) and is mixed back together with the dry/OD at the mixer tube. I believe that's called an anode or "tweed" mixer.

Great job Aaron this looks really good!!

Right. So I understand that the amount of each dry/wet signal is mixed together with the trimmer/return pots, but then isn't the end result that whatever the mix is, will hit the OD circuit, thereby driving the sound of the reverb as well? Or does it somehow sound fine to do it that way in this case? Drive after reverb is OK as long as you can tweak the wet/dry signal mix before it hits the OD?
I'm not trying to sound flippant. I'm just curious. I do notice that my 6G15 sounds not bad in front of my distorted Liverpool against my expectations... Just trying to understand why that is so, yet when I have an HRM OD after my reverb in my Traynor, it gets pretty yucky...

[Aaron]

I don't get the node F on the power supply and what it's connecting to? The plates should be getting 400v from the reverb transformer, is there more voltage being fed in from that node to the plates of v3?

"F" connects to the mixer valve. That's what I could guess from the blurry hand drawn.

Aaron

I see that, but why is there a red lead coming from the node to the feedback loop on the reverb driver tube? And it terminates in the middle of that capacitor. Is it a typo?

Ahhh, I see what you mean. It's not actually terminating at the capacitor, it's going through the chassis to the cap can on the other side.

Aaron

[Aaron]

No, the reverb wet signal is split off the clean channel (at the parallel gain stage around V1b there is a jumper at the grids) and is mixed back together with the dry/OD at the mixer tube. I believe that's called an anode or "tweed" mixer.

Great job Aaron this looks really good!!

Right. So I understand that the amount of each dry/wet signal is mixed together with the trimmer/return pots, but then isn't the end result that whatever the mix is, will hit the OD circuit, thereby driving the sound of the reverb as well? Or does it somehow sound fine to do it that way in this case? Drive after reverb is OK as long as you can tweak the wet/dry signal mix before it hits the OD?
I'm not trying to sound flippant. I'm just curious. I do notice that my 6G15 sounds not bad in front of my distorted Liverpool against my expectations... Just trying to understand why that is so, yet when I have an HRM OD after my reverb in my Traynor, it gets pretty yucky...

Checkout the thread on #60. It's an Overdrive Special with post reverb. There is talk of what sounds better, but beauty is in the ear of the beholder anyway
Aaron

[dreric]

Aaron, As always awesome job.

Thanks!

[ElectronAvalanche]

Hi Aaron,

here are some more, since they seem to make you really happy!

Electron

[Aaron]

Thanks Electron! Did you get to play this amp?

So this amp (serial #???, twenty something?):-
- 68k grid stoppers
- reverb driver 1M0 - .02uf LNFB, 4k7 grid
- .047uf coupling caps

Might be pushing it, but.....You wouldn't happen to have any more photo's

Aaron

[ElectronAvalanche]

Serial is in the low 30s (sorry, can not tell you the serial right now).

I got to play the amp and it sounded really nice.

What section would help you? I will try and see if I have a pic of that section.

Take care and glad to be able to help!

Electron

[tylerbaster]

Found pics of another ods with reverb in Japanese web.Not sure the serial #.The layout looks close to #13.

http://prosoundsos.jugem.jp/?eid=36

[groovtubin]

Found pics of another ods with reverb in Japanese web.Not sure the serial #.The layout looks close to #13.

http://prosoundsos.jugem.jp/?eid=36

AFter translating to english!

Dumble OverDrive Special" Takamine.
The custody by "exchange there C electrolytic leakage, the entire check" and. PRE tube all Nos tube, output tube is used JJ/6L6. Amplifier is made ​​to put great deal of effort. It is built to select as if they are put soul into parts one by one. All of the few cars of Danburu amplifier that we have seen until now, because the wiring is are the mounting by winding the part, you feel like you have a stable operation without a poor contact, such as noise. (?) Substrate is incorporated FET incorporated to distorts the lower right. The admiration Tadatada to pioneer begin to create a Ibitsu-on in this era. Immediately, (part of the blue), Vol / Tone / Jack etc. cleaning of all, check each part, bias Measurement of output waveform and output measurement two exchange electrolytic C × get down to work. There is no need of exchange balance of output tube is good, I had a re-adjustment of the bias. The measured output-aging 90W/4Ω. It's my feeling, but it felt like summer was to (+ distortion) Natural Fender sound sound like passing refreshing after repair.

[Bombacaototal]

Found pics of another ods with reverb in Japanese web.Not sure the serial #.The layout looks close to #13.

http://prosoundsos.jugem.jp/?eid=36

Adding the pics in case the site is ever taken down

[Bombacaototal]

Serial is in the low 30s (sorry, can not tell you the serial right now).

I got to play the amp and it sounded really nice.

What section would help you? I will try and see if I have a pic of that section.

Take care and glad to be able to help!

Electron

Just wondering if you managed to find the serial # for these pics

[Bombacaototal]

For future reference I noticed that the schematic is missing the coupling cap .01uF after V1b and the value of the Trimmer which is 100k but the layout is correct

Does anyone know if the Trimmer is 100ka or 100kb

[Aaron]

Here's the amp in action

https://youtu.be/sl1cOLA4HVs