Dumbleland Special Schematic

[Aaron]

Have been working with Tony (Talbany), trying to get the bottom of the Dumbleland Special #009 amp.
This schematic is unconfirmed but hopefully we can get the ball rolling with this circuit.

Thanks,
Aaron

[martin manning]

I notice the filter circuit is a little different there, it doesn’t have the isolated 3n. Is that based on an actual example?

[Aaron]

I notice the filter circuit is a little different there, it doesn’t have the isolated 3n. Is that based on an actual example?

Hi Martin,
Good catch, have edited the schematic.
Thanks,
Aaron

[erwin_ve]

Is the 12BH7 not supposed to be a cathode follower driven pi?

[Guy77]

Thanks Aaron and Tony for posting this .

I had this idea come to me when I saw your schematic.

I see this is using 3 1/2 preamp tubes. Another single tube for reverb could be added just like the Bloomfield drive has. Then the other half of the unused 2nd tube in the schematic (that is currently set after the Hi Low filters) can drive the reverb recovery and become your Tweed Mixer, mixing the clean and dry signals.

So 5 tubes only and you have a Dumbleland with its cathode follower driven pi and added reverb!

Guy

[talbany]

Is the 12BH7 not supposed to be a cathode follower driven pi?

Erwin
Not as far as what we know so far you are thinking about the ones used in the SSS amps..We think the Dumbleland used the same 12AU/12BH7 driver configuration as the Odyssey

Tony

[talbany]

Thanks Aaron and Tony for posting this .

I had this idea come to me when I saw your schematic.

I see this is using 3 1/2 preamp tubes. Another single tube for reverb could be added just like the Bloomfield drive has. Then the other half of the unused 2nd tube in the schematic (that is currently set after the Hi Low filters) can drive the reverb recovery and become your Tweed Mixer, mixing the clean and dry signals.

So 5 tubes only and you have a Dumbleland with its cathode follower driven pi and added reverb!

Guy

That sounds cool There are all kinds of different directions you can go with the schematic as far as different drivers and reverbs and power tubes is wide open and free to your interpretation.. We kept this version stock and what we know about the Dumbleland and ser #009 to start the discussion and just to get what we know out there documented for those who like the amp.
Perhaps in the future if we get more time we can do the Dumbleland /w Reverb

Tony

[Max]

Is that based on an actual example?

AFAIU the preamp is based on some schematic of SSS100W#002 circulating here:

… I pulled the schematic from 002 and ditched the reverb and wala! Dumbleland. Dumbleland is supposedly a bass amp so I would imagine it might have a slightly different tonestack.I don't play bass so used the Classic/Deep configuration …

And AFAIU the poweramp is based on some schematic of some Odyssey 100W circulating here:

… Just checked, it's the Odyssey amp I'm referring to. Basically, the PI/driver board topology of the Dumbleland style clone that TR built for me is nearly identical in toplogy (values different though) to that shown here: https://ampgarage.com/forum/viewtopic.p ... it=odyssey …

Thanks! The Winterland closely resembles the Williamson /Split load..The Odyssey is LTP (common cathode) and driver
They both appear to have similar driver set ups accept for the .22 couplers on the Winterland vs the .1 for the Odyssey which is more than likely set up for guitar and that Winterland for bass..I assume?
(The give away is the common cathode on V1 and V2 of the Odyssey.. The Winterland has no shared cathode on V2..If they were similar both V2 and V3 of the Winterland would be shared like the Odyssey.Both are AC driven.

Quotes from this thread: https://ampgarage.com/forum/viewtopic.php?f=4&t=34367

BTW: Here's a picture showing DL#009 in the early 90ties:

DL.png

Cheers,

Max

[talbany]

And AFAIU the poweramp is based on some schematic of some Odyssey 100W circulating here:

Max
Thanks for jumping in!
AFAIK Dumble utilized 3 different P.I driver configurations
1. SSS w/ 2 7025's like used in #002 here

SSS-002-JD-1-2.pdf

2. Winterland (williamson) This is the one used in amps like the Marshall Majors and Ampeg V9 here is the schematic
3.Odyssey uses this 12AU/12BH7 PI Driver combo Here is the schematic

ODYSSEY GUITAR.jpg

Aaron.jpeg

As you will notice all 3 of these are different style Drivers.
Here you wrote

The Odysseys have a PI that's more or less similar to the Dumbleland With some simplification you could perhaps think of an Odyssey as a 100W version of the power amp of a Dumbleland. For my ears a Dumbleland in best shape (tubes, filter caps etc.) has the "purest" tone of all.With an Odyssey you move at least one or two steps into Dumbleland territory.

Again you wrote?

And what comes to my mind right now: The Odysseys have a PI that's more or less similar to the Dumbleland PI. And if you listen to EJ manzamp/odyssey sounds you will find nothing dull too. Or remember Kevin Dukes: Two Odyssey power amps in his rack and nothing dull or flat in his guitar tone!

Again

As far as I know and remember now the only similarity between an Ampeg V9 and a Dumbleland 300SL is the use of the same kind of transformers. Otherwise rather different as far as I remember now.
As far as I remeber a Dumbleland 300SL has more in common with a Dumbleland 150W and a SSS as with an Ampeg V9.

https://ampgarage.com/forum/viewtopic.p ... sey#p85298


As far as the tone stack goes
You wrote

Just try this with a 4th generation "classic" and you’ll perhaps understand what Alexander is talking about (in 1985 the "skyline" amps had not yet arrived in Dumbleland).

I didn't use the TS from 002. i think of it as we used the 4th Generation "Classic" like you mentioned above and it so happens that 002 had this same classic tone stack..Yes the filters were from #002.

So If you can confirm any errors made on Mine and Aarons schematic I am sure the Amp Garage would appreciate it Otherwise we'll go by what you wrote.
BTW.I like the old knobs better
Tony

[Aaron]

Thanks Aaron and Tony for posting this .

I had this idea come to me when I saw your schematic.

I see this is using 3 1/2 preamp tubes. Another single tube for reverb could be added just like the Bloomfield drive has. Then the other half of the unused 2nd tube in the schematic (that is currently set after the Hi Low filters) can drive the reverb recovery and become your Tweed Mixer, mixing the clean and dry signals.

So 5 tubes only and you have a Dumbleland with its cathode follower driven pi and added reverb!

Guy

I built this 5-6 years ago. Power amp is a pair of vintage KT88's.

[dorrisant]

Is it just me, or does that filter set before and after the standby switch look strange? Looks like 50μF before and 50μF after that would combine for 100μF when the switch is is operate. Very cool... im wondering what Aaron's sounds like.

Very cool guys, much appreciated!

[Max]

... 2. Winterland (williamson) This is the one used in amps like the Marshall Majors and Ampeg V9 ...

Are you sure?: Marshall Major: https://drtube.com/schematics/marshall/1967u.gif vs. Ampeg V9 https://ampeg.com/support/files/Schemat ... Manual.pdf

... 3.Odyssey uses this 12AU/12BH7 PI Driver combo ...

AFAIR all the Odyssey amps have 4 power tubes (this schematic = 2). And AFAIR elsewhere you wrote that there isn't a fixed relation between the kind of tubes (2x7025 vs. 12AU/12BH7) used and the kind of coupling (AC vs. DC).

... Otherwise we'll go by what you wrote. ...

My personal recommendation: One should perhaps take into account the possibility that what I wrote may be wrong and/or that the contents of somebody's personal perception/interpretaion of what I wrote may differ from the contents I intended to communicate in my personal anecdotal descriptions.

Cheers,

Max

[talbany]

... 2. Winterland (williamson) This is the one used in amps like the Marshall Majors and Ampeg V9 ...

Are you sure?: Marshall Major: https://drtube.com/schematics/marshall/1967u.gif vs. Ampeg V9 https://ampeg.com/support/files/Schemat ... Manual.pdf

... 3.Odyssey uses this 12AU/12BH7 PI Driver combo ...

AFAIR all the Odyssey amps have 4 power tubes (this schematic = 2). And AFAIR elsewhere you wrote that there isn't a fixed relation between the kind of tubes (2x7025 vs. 12AU/12BH7) used and the kind of coupling (AC vs. DC).

... Otherwise we'll go by what you wrote. ...

My personal recommendation: One should perhaps take into account the possibility that what I wrote may be wrong and/or that the contents of somebody's personal perception/interpretaion of what I wrote may differ from the contents I intended to communicate in my personal anecdotal descriptions.

Cheers,

Max

Max
I just didn't go by what you said about the Dumbleland only I had others that contributed as well..

Again If you see something that is not correct and want to positively identify something that is incorrect that would be great.
Otherwise the schematic stands as is.

Tony

[talbany]

Here are a few more things we know so far about #009

PT is what looks like Triad R-25A.Should deliver around 530 VDC (bias depending) Screens around 327
made 42nd week of 1968
Output transformer is from a Sunn 1200S Ultralinear (4x6550) amp. The Sunn original part# is 28-1312, 3-120T
(Looks like it has the same iron as ODS #121 (ODS150) made for Todd Sharp)
Choke 3-5H, ca 150mA (4X6550)

Let me know if someone has anything different



Tony

[Bombacaototal]

Great topic, my small contribution.

Here is my therad of 1973 Odyssey Deluxe
https://ampgarage.com/forum/viewtopic.p ... it=odyssey

Dumble It is Odyssey Concert Deluxe Amplifier 100W # 015 [Super Rare] made in 1973
Illusory amplifier, Dumble 1972 Odyssey Concert Deluxe 100 W Power Amplifier arrived.
It's been a while since then, Dumble Amp came to HOWL GUITARS.
Dumble Amp, made by Howard Alexander Dumble, is now a mythical presence in the boutique amp world.
Among the fewer existences, the individuals that arrived this time will be one of Dumble Amp's serial number 15 of the early 73 years.
Odyssey Concert Amp is said to be an amp model whose production was begun by asking the owner of a club called "Odyssey Club" in the US to make a power amp that can be used on stage at the dumbbell.
As the main use in the 1970s, the method of connecting the preamplifed amplifier head to the Odyssey Concert Amp and using a unique "Dumblize" sound, or simply used for cross-stage monitoring It seems that it was.
It is a simple power amplifier that can be used regardless of guitar, bass, keyboard and musical instrument, as an amplifier that produces a clean and pure tone quality, it is the best among the dumbbell amps.
Odyssey Concert Amp is only made in the metal panel period (which becomes a black panel in the later years) which is the feature of the early dumble amplifier in the 70's, and it is said that the total production number is less than 30.
The initial Odyssey's feature is the gold metal panel in a compact cabinet size. The model notation of the front is "Odyssey Concert Amplifier". However, this individual is written as "Odyssey Concert Deluxe Amplifier" not found in other individuals.
(Incidentally Odyssey in later years gets bigger cabinet size and will only enter Odyssey Concert on Silver Metal Panel.)
Along with Dumbleland Special and Wniterland, the crystal clean sound of the initial Dumble amp.
When using a preamp or an effector of an overdrive type, it produces a tremendous sound.
It's a pretty rare collector's piece that Dumbble Mania around the world is looking for.
Then release your photo.
Initial specification gold metal panel. INPUT x 2 / VOLUME / ACCENT SWITCH
Model name in the center of the front panel. Odyssey Concert Deluxe Amplifier. If lettering is DUMBLE.
It is on the right side of the front panel. Pilot lamp, Oparate / Standby, On / Off, Ground switch.
4 Ω speaker output. On the right side is the RCA type Input
It is a serial number struck by the back panel. # 015 Initial individual.
It is a main transformer. It is a transformer made by Fender that was used for high output amplifiers such as Twin Reverb and Showman.
It is a choke transformer. Also made by Fender.
It is an output transformer. Also made by Fender.
It is inside the chassis. I do not open the interior of the dumble amplifier in particular (Dumbleland Special made in 1978 which we arrived last time, etc.), this individual is a power amplifier, so it will be okay
It is the main part of the amplifier. The backside of the main transformer.
It is a pot of bias adjustment. Pot date is 137 - 7218. Week 18 of 72 years
It is an electrolytic capacitor. Characteristics of the dumbble amplifier, tag board is handmade with rosewood.
Here too the tag board is handmade with rosewood.
It is the back side of the front panel. It is a volume pot and jack and an accent switch.
It is the back side of the front panel. Switch such as pilot lamp and power ON / OFF.
It is the back side of the back panel. It is FUSE BOX and AC OUTLET.
It is the back side of the back panel. Speaker output jack.
70s Dumble 4x12 in our shop "with Cabinet and a click here.
(Note) The cabinet is NOT FOR SALE Death.

I am also adding a high resolution of the #12

The power section is based of Mcintosch MC275, schematic attached

I am also adding the schematic of 15 with some correctinos to Aarons 12 and some remarks in yellow

I build this exact power section (except for LTPI, where I used later HAD values) and it sounds gorgeous!

Hope it helps