ODSR #13 Hand drawn layout by H.A.D

[Max]

Reverb > OD:

https://www.youtube.com/watch?v=oF5bz61SJu4

http://ampgarage.com/forum/viewtopic.ph ... 52#p188952


OD > Reverb:

https://www.youtube.com/watch?v=fMIJuuk1SFs

https://www.youtube.com/watch?v=LfBgrtPbxOg


Have a nice weekend!

Max

[philbard]

Can you post that please.

Thanks
Tony

Got the impression that the one in the first post in this thread was created from the drawing. Is this not the case?
https://ampgarage.com/forum/viewtopic.php?f=4&t=22855

[Stephen1966]

Tony, I had a look at your drawing in Photoshop... When I am working with old manuscripts, I find it is sometimes helpful to invert the image. Here is the inverted image:

1200DPIDumbleLayout-3.pdf

And to this, I also applied an unsharp mask. Too much and this puts a halo around the characters - it becomes unreadable in a different way! There are other sharpening strategies - high pass filters (of the visual kind) but there isn't enough resolution in the original image to work with. This is a little better, but when you zoom in to read those written values, it is heavily rasterised. Do you have a higher resolution copy of this drawing?

Here's the drawing widened - yours appears to have a compressed width - probably a setting in the pdf output that was used.

1200DPIDumbleLayout-1.pdf

Stephen

[talbany]

Can you post that please.

Thanks
Tony

Got the impression that the one in the first post in this thread was created from the drawing. Is this not the case?
https://ampgarage.com/forum/viewtopic.php?f=4&t=22855

I have 3 schematics here of supposedly #013. All a little different at first glance.

Aaron says

Thought I would have a go at tidying up the blurry hand drawn layout that is supposed to be ODRS #13, dated 8th August 76.

Circuit is not 100% confirmed. Some values that I couldn't make out I took from the 2nd Gen files.

I have not built or tested so assume it has errors.

If anybody knows or has seen this amp I would appreciate any input. Feel free to send me anything

A quick glance at Aaron's schematic has a 100k mid pot and #13 is pretty clearly marked on the hand drawn 250KA (As is all 2nd generation amps)https://ampgarage.com/forum/download/fi ... &mode=view Perhaps he can comment? (BTW.Not meant to flame him Aaron does great work!! )
Tony

[philbard]

I have 3 schematics here of supposedly #013. All a little different at first glance.

Aaron says

Thought I would have a go at tidying up the blurry hand drawn layout that is supposed to be ODRS #13, dated 8th August 76.

Circuit is not 100% confirmed. Some values that I couldn't make out I took from the 2nd Gen files.

I have not built or tested so assume it has errors.

If anybody knows or has seen this amp I would appreciate any input. Feel free to send me anything

A quick glance at Aaron's schematic has a 100k mid pot and #13 is pretty clearly marked on the hand drawn 250KA (As is all 2nd generation amps)https://ampgarage.com/forum/download/fi ... &mode=view Perhaps he can comment? (BTW.Not meant to flame him Aaron does great work!! )
Tony

I sharpened it a bit after adjusting the contrast to try to improve its readability, its a pretty crappy photo, low res, so sharpening beyond a small amount only makes things worse. A higher res version, if its out there anywhere would be better material to work on, even if its a bit soft. Or an image that isn't in jpg form though I suspect that's unlikely.

[talbany]

I have 3 schematics here of supposedly #013. All a little different at first glance.

Aaron says

Thought I would have a go at tidying up the blurry hand drawn layout that is supposed to be ODRS #13, dated 8th August 76.

Circuit is not 100% confirmed. Some values that I couldn't make out I took from the 2nd Gen files.

I have not built or tested so assume it has errors.

If anybody knows or has seen this amp I would appreciate any input. Feel free to send me anything

A quick glance at Aaron's schematic has a 100k mid pot and #13 is pretty clearly marked on the hand drawn 250KA (As is all 2nd generation amps)https://ampgarage.com/forum/download/fi ... &mode=view Perhaps he can comment? (BTW.Not meant to flame him Aaron does great work!! )
Tony

I sharpened it a bit after adjusting the contrast to try to improve its readability, its a pretty crappy photo, low res, so sharpening beyond a small amount only makes things worse. A higher res version, if its out there anywhere would be better material to work on, even if its a bit soft. Or an image that isn't in jpg form though I suspect that's unlikely.

I agree Phil
I tried Photoshopping this thing 10 ways to sunday to try and enhance it and in most cases only made things worse. Unless there is someone out there that has any better ideas or some kind of forensic software to make it readable? or some detailed shots..
I don't know? it was worth a shot!..Having looked at it for about an hour I can determine about half the layout.

Thanks!

Tony

[Max]

Unless there is someone out there that has ... some detailed shots..

https://ampgarage.com/forum/viewtopic.p ... 39#p294839

http://www.antiqueamp.com/dumble/amporg.html

Cheers,

Max

[talbany]

Thanks Max

Erwin already posted this in the 2nd post however what amp is this?
https://ampgarage.com/forum/viewtopic.p ... 39#p294839
and do you know the serial # Judging by some of the components (Flexfoam/Mepcos TVA's say 77) it does look like a 2nd generation
So It looks like Aaron took bits and pieces from different Ser# ODSR's
BTW.Enjoyed the article on Bobby

2nd generation Overdrive Reverb:
3 tubes (driver, return amp, mix amp,). Mix is done before the OD circuit. So you have ìoverdriven reverbî. By this the reverb gets the more prominent, the more the OD decays. It is a bit like with a Deluxe Reverb in power amp saturation mode. When the note decays, the reverb gets more prominent. These amps have less gain AFAIR than the usual 2nd generation ODS.

3rd generation Overdrive Reverb: No idea

4th generation Overdrive Reverb:
3 tubes (driver, return amp, mix amp). Reverb send is behind volume and ratio, mix before master volume. By this the reverb is a bit like an effect in the loop.

Tony

[Aaron]

Hi guys,

The 100k was probably an over sight. The bulk of my schematics and layouts were done when I was working full time and only time I had to do them was late nights, there were many 2-3am nights!

Tony, doesn't SSS #005 have the "Tweed" mixer circuit, which is my favourite too!

Aaron

[Aaron]

Unless there is someone out there that has ... some detailed shots..

https://ampgarage.com/forum/viewtopic.p ... 39#p294839

http://www.antiqueamp.com/dumble/amporg.html

Cheers,

Max

Hi Max,

I think those amps are OD-50WR #0030 and OD-100WR #0081. Both are pre OD.

Aaron

[talbany]

Hi guys,

The 100k was probably an over sight. The bulk of my schematics and layouts were done when I was working full time and only time I had to do them was late nights, there were many 2-3am nights!

Tony, doesn't SSS #005 have the "Tweed" mixer circuit, which is my favourite too!

Aaron

Aaron
Hello!. So just to be clear the bulk of the info obtained for your layout was from the hand drawn or was it from the 2nd generation Electron posted or did you use both?..Just trying to get an idea as to where you collected all your data,was it from 1 amp or several and did you embellish any along the way?.. Believe you me having done my fair share of these reversed engineered layouts Time consuming is an understatement and typos will happen!
From Electron

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

AFAIK Dumble used the "Tweed mixer" in SSS #002. (I built one) not sure about 05. I know it was not in 07 (Bruton-EJ) 004 and 002

I've often wondered given how well that mixing section works (transparent and controllable) he didn't eventually integrate it into his ODSR's...If i were to design one the T.M would be how i would try to do it. (After the OD ) The other thing is go with either a straight Classic or Skyliner stack and not the one used in the 2nd gen amps..IMO
BTW. The tone reviews on 13 I have heard have been mixed? Did you build it and if so were you impressed?
Thanks!!
Tony

[Aaron]

Aaron
Hello!. So just to be clear the bulk of the info obtained for your layout was from the hand drawn or was it from the 2nd generation Electron posted or did you use both?..Just trying to get an idea as to where you collected all your data,was it from 1 amp or several and did you embellish any along the way?.. Believe you me having done my fair share of these reversed engineered layouts Time consuming is an understatement and typos will happen!
From Electron

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

AFAIK Dumble used the "Tweed mixer" in SSS #002. (I built one) not sure about 05. I know it was not in 07 (Bruton-EJ) 004 and 002

I've often wondered given how well that mixing section works (transparent and controllable) he didn't eventually integrate it into his ODSR's...If i were to design one the T.M would be how i would try to do it. (After the OD ) The other thing is go with either a straight Classic or Skyliner stack and not the one used in the 2nd gen amps..IMO
BTW. The tone reviews on 13 I have heard have been mixed? Did you build it and if so were you impressed?
Thanks!!
Tony

Hi Tony,

The bulk of it was from the hand drawn layout, squinting as much as I could to try and make out most of the values.
It was unconfirmed and I mentioned if there was any errors let me know, no-one did until 8 years later

I built an #0013, but the reverb can get lost with the overdrive channel. I prefer the post reverb circuit as in #0060. But then the reverb can get too much, depends on how you set the overdrive level. I would mind having a go at building something like #0137 with "clean" and "overdrive" reverb controls.

Do you refer to the SSS #002 as "Tweed" because the signals are from the cathodes? AKAIK SSS #001 and SSS #002 had the same mixer circuit, #004 is similar to this ODR #0013 and SSS #005 is from the wiper?

Aaron

[talbany]

Do you refer to the SSS #002 as "Tweed" because the signals are from the cathodes? AKAIK SSS #001 and SSS #002 had the same mixer circuit, #004 is similar to this ODR #0013 and SSS #005 is from the wiper?

Correct! Mixing is done at the cathode end or low impedance mixer. This generally requires an extra tube so your typical SSS (with trem) Reverb with Tweed mixer (4 tubes) and P.I Driver would be 8 total. Others were called 3 tube reverb's

#001 Keiser amp 8 tubes w/driver Mixer sec bottom right front

SSS#4.jpg

SSS_Schematic.jpg

#002 Schematic taken from hand drawn schematic from Japan 8 tubes Tweed Mixer

SSS SN002.jpg

#00? Commissioned by Ry Cooder (Snakeskin) Pentode amp (AFAIK) 3 tube reverb

Pentode_SSS_Preamp.pdf

Tubes and their function 2xEF (input, recovery after EQ), 7247 (reverb mix), 7025 (reverb return), 12AX7 (tremolo), 5751 (reverb send), 7025 (phase inverter), 7025 (driver), 4 x 6550A.

SSS Preamp+Verb+Tremo-Board.pdf

SSS #004 Keiser (six preamp tubes) No Tweed No Driver

sss51.jpg

SSS #005 Santana/Bruton (I believe this is also the one Brandon used for his High Planes Drifter) no Driver no Tweed

SSS005_lay_v01.png

During the early days the ser#'s on the SSS quite often got confused or were simply wrong..So if something is not right let me know and will correct it.

Thanks for the rundown on #0013. Sort of sounds like some of the other reviews I've been getting.
Tony

[mojotom]

Thanks Aaron and Tony !

I wouldn’t mind the reverb disappearing on OD as long as it’s not over powering and washed out by the OD.

I guess 13 is a lower gain affair too as the clean is quite attenuated (like a JM) right at the output of V1b before the reverb stages.

How does it sound clean Aaron with that reverb and output stage compare to the others amps you build (SSS and the pentode amp for exemple) ?
I was thinking more about a clean with reverb amp with an additional OD rather than an ODS with reverb.

And btw do you have a favorite tank for those 3/4 tubes reverb ?
I’m a bit lost on reverb choice. Lately I use a classic Fender 2 springs like 4AB2A1B.

[Max]

... your typical SSS (no trem) Reverb with Tweed mixer (4 tubes) and P.I Driver would be 8 total.

Hi Tony,

why do you think so? I ask, because AFAIK all Dumble amps with 8 nine-pin tubes have a trem circuit?

All the best,

Max