Dumble OVERDRIVE SPECIAL OD-50WX on ebay

[dbharris]

That is the Hoyt Axton amp, right?

-Dan

[mikeram]

I'm hoping that Max has more info on this but to answer your question, Here's a picture of the serial number:

Mike

[Max]

I have only seen a few ODS pictures with "modular" PCB construction.

At the moment, I, too, can recall only two Transition Generation ODS amplifiers—each featuring separate circuit boards for V1, V2, and V3—namely, the one owned by Hoyt Axton (above, which has no serial number) and this one built for a customer named Don Alvarado (serial number #0080):

Don Alvarado #0080.jpg

OD-50W #0080.jpg

That is the Hoyt Axton amp, right?

Yes, absolutely right.

Here's a picture of the serial number

And as you can see, there is no serial number on the Hoyt Axton. To the best of my knowledge, there are some "transition generation" ODS chassis that feature a screen-printed serial number rather than a stamped one. Some examples include #0075 (Steve Farris), #0077 (Steve Haggerty), #0079 (Tom Verlaine), and #0080 (Don Alvarado). It is therefore possible that the transition-generation chassis of the ODS built for Hoyt Axton lacked a stamped serial number and—for whatever reason—also lacked a printed one. And as far as I know, Alexander Dumble would sometimes even use a 2nd-generation chassis from the 70s for an ODS built in the 80s:

Denis Herring OD-50Wjpg.jpg

Denis Hering OD-50W back.jpg

And the fact that different Dumble model designations are usually associated with different serial number ranges, and the same serial number can therefore appear multiple times on Dumble amps (e.g. Odyssey #020, #023, #025 vs. Overdrive Special #0020, #0023, #0025), sometimes may cause additional confusion. And then, of course, there are amplifiers where the serial number was altered—such as SSS #002. Perhaps for SSS-100 #002 he used an ODRS chassis that already had a stamped serial number from the ODRS series range, and which he therefore modified? But that is, of course, just a speculation.:

SSS-100 #002.jpg

While writing this post, by the way, I just came across a picture of the interior of Eric Johnson’s Odyssey #0004. And IMO in terms of cleanliness and the sheen of the solder joints—accentuated by the lighting—it creates an impression rather similar to the pictures of the OD-50WX #0023 discussed here.

Odyssey #0004.jpg

[dbharris]

Thanks for the additional info Max.

I wonder if this amp has a serial number in HAD's records and for whatever reason it was never placed on the amp or was removed at some later time. Those number stamps can be quite difficult to hammer in and never look very precise. I could imagine this bothered HAD and he looked for an easier and better method.

In college, I bought one of the first Asher lap steel guitars when he moved the junior production to Asia. The serial number was applied with a paint pen on the back of the headstock and in the control cavity. One day a friend of mine rubbed his thumb over the serial number on the headstock and it wiped right off. You would never know any had been there.

Alternatively, maybe the Hoyt amp was a prototype for HAD in trying out the circuit board style builds and that is why it was not serialized and has a more rare chassis screen printing. Though I believe other "prototypes" of HAD are serialized and of course there is the belief that to HAD everything was a one off prototype of some sort.

Off topic here Max, but I'm wondering if you might have any pictures of the internals of 1st gen amps you would be able to share? Or SSS #0003?

-Dan

[Max]

... picture[s] of the internals of 1st gen amp[s] ...

At the very least, I found this. Unfortunately, the image quality is rather mediocre. If I happen to find more in the near future, I’ll post an update here—or in another thread, should the moderators prefer to place this image (or a copy of it) elsewhere.

[dbharris]

Max, thank you so much. I cannot recall ever seeing this before. This is very interesting. Do you know anything about the history of this amp that you are able to share?

For instance, I wonder if it was updated by HAD at some point? See LNFB at V1, which we usually associate with circuits typically found in transition gen and classic amps. A single draloric (or maybe an iskra?) resistor.for the GNFB, a balance trimmer in the PI.

Then there are lots things that must be specific to 1st gen amps before being further refined, like most of the FET circuit positioned on the main board, choice of parts, etc. I'm sure I will notice more as I study it.

All the best and thanks again.

-Dan

[Max]

… Do you know anything about the history of this amp … ?

If I recall correctly, this 1st-generation ODS initially remained in its birthplace, Santa Cruz. In the 90s, the amp spent some time in Europe. For instance, in 1999, it was used during a live performance of Peter Wolf’s composition "Progression" in Linz, as part of the "Linzer Klangwolke" (Linz Cloud of Sound) event, in front of an audience of approximately 120,000 people. Later, I spotted this same ODS at a shop in the U.S.A. that, at the time, was selling a lot of items created by Alexander Dumble.

… For instance, I wonder if it was updated by HAD at some point? …

I do not know whether Alexander Dumble built this ODS in the configuration shown in the photo above from the very beginning, or if it only took on that appearance following a later modification. In my personal opinion, both scenarios are plausible.

… I'm sure I will notice more as I study it.

Have you already spotted any other such details?

If I recall correctly, this first-generation ODS was used at this concert by the guitarist positioned on the left side of the stage (from the audience's perspective):



And here is a short clip from this concert in which this guitarist plays a rhythm part and a brief solo part using this amplifier:

Coolio_(Peter_Wolf_Progression).mp3

[dbharris]

… I'm sure I will notice more as I study it.

Have you already spotted any other such details?

Hi Max,

Thank you for the reply and additional information/history of the amp. I will certainly give that a listen soon.

Yes, some other items I have noticed that lead me to believe the amp was certainly modified at a later date (who knows if by HAD, some other person(s) or a combination) are:

1. The heater wiring. I believe both wires in solid red is what we would typically see in an untouched Dumble amp from the first and second generations. Here it starts that way, then goes to red and black, then black and yellow.

2. The same black and yellow wires are used in the effects loop, which is a full send and return, not a send only as is typically found in 1st through 3rd gen amps. Additionally, the stereo switching jack appears to be of a part type not manufactured when this amp would have originally been built, especially compared to all of the other 1/4 jacks that are visible.

Other "quirks" I have noticed:

A. I believe the red box near the input jacks is a trimmer to set the FET Volume. It appears to be glued to the chassis with RTV. But it sort of looks like the triad inductors he used in some other amps.

B. Some ground and perhaps b+ wires sent to the bus bar and main board appear to have been routed outside the chassis via holes and grommets and then back in.

C. Cap can in the back corner by the AC input, this appears in several other amps of the same era.

D. No dedicated power supply board, terminal strips instead. No relay PT.

E. Shielded cable is pre the Columbia flex foam. One run is a different type of shielded cable into the OD entrance.

F. Grid resistor for v1a is either on the input jack or hiding in the shrink wrap after the shielded cable right before the pin.

G. Interesting capacitor choices compared to later amps. Less orange drops, I believe the black drops are Mallory.

H. Not running the cathode lead of v1a and v2a up and around the socket as was usually (but not always) the case in later builds.

I. No bypass or peaking cap in the funky OD entrance. There is a peaking cap on OD2 out.

I'm sure there is more I am missing and that is without looking at parts values b/c I don't have resistor color code bands memorized.

Curious what thought or observations others may have.

-Dan

[Max]

Hi Dan,
Thank you! In the meantime, I’ve found another (even worse) picture of the other side of of this 1st gen. ODS:

1st gen. ODS chassis outside.jpg

More thoughts on what you have noticed as soon as I have the time for it.

Thanks Neskor! Lots of good photos there.

and (as I just noticed) a short video to demonstrade the tonal character of ODS #0023. To me, the guitar sounds most like a Stratocaster(?).