Which ODS is "correct" - totally confused!

[Aurora]

I signed up here over ten years ago, thinking I should get something done with an ODS, but life got in the way. Now I'm trying to get back on track, but the amount of info that has piled up in the D-section is truly overwhelming, and quite frankly I seem to be unable to sort out which schematic and layout is "correct" between all the iterations posted. I'm looking for an basically for an ODS 50 or 100 ( or maybe use the switch option)...
Any solution or pointers as to which sch-layout combo that can be "trusted"? ( I know there's "a few 'variations' out there.. but still...)

[pompeiisneaks]

There is no 'correct' Overdrive Special (BTW Dumble never called them ODS and Fuchs has claimed the ODS name, so technically it's wrong to call them ODS ), there are hundreds of variants based upon how he built them for the specific guitar player. The reason there are so many is they're based on the serial number of the amp AND in some cases (#124) he went back and modified the amp a second time, converting it from a low plate classic to a high plate, etc. Therefore the 'layout' and 'schematic' changed for that specific amp. Basically you'd need to either :

A: build many of them
B: mod some with specific mods he's done on a regular basis

There are tons of 'base' mod he did and then 'tweaked' too. You'd have to determine what specific amp is the sound you're shooting for before deciding on a specifc amp, and even then some people don't like the way that amp sounds and mod it again to be more like another etc. Some of the changes are pretty easy, going from low plate to high plate is pretty simple, just a few component changes in the resistors if I recall (I've not done it yet, and am only on my first build of a #124, thus why I'm familiar with it).

Others that know a LOT more than me can probably give a good summary of the variants, in fact I seem to recall there being a thread someone did that summarized the known ones here, but I may be mistaken and that would be a great document to have detailing the known variants and builds we have here.

~Phil

[Aurora]

Thanks, much, - so far... #124 is probably the one with the most info... can one assume that the layout and schematic presented on the first pages are updated in accordance with the many post and suggestions later int thread, except for component variations mpre rerlated to "voicing"? Are your videos mainly based og this version?

[pompeiisneaks]

My videos are solely based on this version, yes they seem mostly 'right' but the layout seems to have a decent amount of things that are hard to follow for me, but it's also a super complex amp. The layout I'm using there seems to fit the original '84 schematic, but the new updates he did to that SN is listed as a second schematic, so you know what components to change etc.

I'm building the original '84 one.

~Phil

[xtian]

I built #183, and found the documentation good. There's still a lot of care needed to decipher the correct wiring for the relays, and other minor details, but no show stoppers.

Here is my build thread: https://tubeamparchive.com/viewtopic.php?t=30282

[Guy77]

Which ever one you build add a dumbleator to it! For me the tome was so much richer and better with the dumbleator. Better yet add it to the actual build .

Cheers

Guy

[drew]

To try to ease your way back into it without getting lost in the minutia, I would suggest reviewing recent threads and posts by norburybrook (Marcus). He has built most of the common Dumble variants, does a good job commenting on the strengths and weaknesses, and speaks from the perspective of a working musician rather than just a home hobbyist builder. (No knock on the latter; I'm one of them.)

[norburybrook]

To try to ease your way back into it without getting lost in the minutia, I would suggest reviewing recent threads and posts by norburybrook (Marcus). He has built most of the common Dumble variants, does a good job commenting on the strengths and weaknesses, and speaks from the perspective of a working musician rather than just a home hobbyist builder. (No knock on the latter; I'm one of them.)

Thanks Drew. I'll add that I was a complete novice when I first came here and you'll see from my build threads I needed a lot of 'hand holding' to trouble shoot my early builds.

Main thing is, even though I was a novice, I was well aware of the safety issues involved in tube amp building so always used safe practices, probably was a bit too concerned in the beginning but gradually relaxed when I felt more confident. You're probably further down the line than I was so if you can solder well, follow a schematic/layout then you should be fine.

why not start with the #124 as Phil is making one at the moment and is running video's of the build, what could be better? The #124 is a good middle ground amp and can be converted to a #102 easily if you don't like it and it has great documentation. I would say #102-184 all have a characteristic 'family' sound so whichever you build you'll find out if you like the overdrive special, some don't, they're not for everyone. The bluesmaster is probably the most different from thses amps, but even that has the dumble family sound. Great cleans and a more raucous OD when used with the PAB, it's one of my favorites, again great documantation. I don't think it matter what you build first, just build one.


Marcus

[dbeasley]

From my experience, I've found that for whatever reason you will ALWAYS end up tweaking the hell out of your very first Dumble build, regardless of where you start. It only seems to get easier to make them sound fantastic after you've had several under your belt. As far as completeness goes, most of the important details for most of the variants are pretty well cataloged in the Dumble files.

TBH, I never found one being easier over another (with the ODS circuits). They all share a somewhat common preamp and PSU eyelet board, which I believe someone here has kindly provided templates for. You could start making those boards first, then listen to lots of clips (also thread on that somewhere) and start from there.

Be careful. Dumble amps are like Pokemon...you will eventually want to build them all [emoji3]

Sent from my Moto G (4) using Tapatalk

[pompeiisneaks]

From my experience, I've found that for whatever reason you will ALWAYS end up tweaking the hell out of your very first Dumble build, regardless of where you start. It only seems to get easier to make them sound fantastic after you've had several under your belt. As far as completeness goes, most of the important details for most of the variants are pretty well cataloged in the Dumble files.

TBH, I never found one being easier over another (with the ODS circuits). They all share a somewhat common preamp and PSU eyelet board, which I believe someone here has kindly provided templates for. You could start making those boards first, then listen to lots of clips (also thread on that somewhere) and start from there.

Be careful. Dumble amps are like Pokemon...you will eventually want to build them all [emoji3]

Sent from my Moto G (4) using Tapatalk

Be careful of those boards, I think they work very well for some circuits but not for others. I tried them, cut them drilled and eyelet boarded them to find out they don't match the #124 layout they're very well done, but just make sure what does and doesn't work for your build.

~Phil

[dbeasley]

From my experience, I've found that for whatever reason you will ALWAYS end up tweaking the hell out of your very first Dumble build, regardless of where you start. It only seems to get easier to make them sound fantastic after you've had several under your belt. As far as completeness goes, most of the important details for most of the variants are pretty well cataloged in the Dumble files.

TBH, I never found one being easier over another (with the ODS circuits). They all share a somewhat common preamp and PSU eyelet board, which I believe someone here has kindly provided templates for. You could start making those boards first, then listen to lots of clips (also thread on that somewhere) and start from there.

Be careful. Dumble amps are like Pokemon...you will eventually want to build them all [emoji3]

Sent from my Moto G (4) using Tapatalk

Be careful of those boards, I think they work very well for some circuits but not for others. I tried them, cut them drilled and eyelet boarded them to find out they don't match the #124 layout they're very well done, but just make sure what does and doesn't work for your build.

~Phil

Yes I can see how they wouldn't work *exactly* for things like the funky OD 70s entrance.

Sent from my Moto G (4) using Tapatalk

[martin manning]

Be careful of those boards, I think they work very well for some circuits but not for others. I tried them, cut them drilled and eyelet boarded them to find out they don't match the #124 layout they're very well done, but just make sure what does and doesn't work for your build.

Which board layouts are you referring to here Phil? All ODS preamp and power supply boards are very similar, and I think any of the amps documented here can be built using the same basic pattern.

Yes I can see how they wouldn't work *exactly* for things like the funky OD 70s entrance.

There is a space for that on the JBoarders/CE chassis board.

[norburybrook]

I think the only thing you'd have to change would be the cathodes caps/resistor wiring. on the earlier models they're separate ones stretched out across the board, you could just position them like the later models if you wanted i.e both meeting in the middle for their ground.


M

[Aurora]

Thanks, guys, - so far.... I'l start digging into this again.... I may be back for "more" questions...

[pompeiisneaks]

Be careful of those boards, I think they work very well for some circuits but not for others. I tried them, cut them drilled and eyelet boarded them to find out they don't match the #124 layout they're very well done, but just make sure what does and doesn't work for your build.

Which board layouts are you referring to here Phil? All ODS preamp and power supply boards are very similar, and I think any of the amps documented here can be built using the same basic pattern.

Yes I can see how they wouldn't work *exactly* for things like the funky OD 70s entrance.

There is a space for that on the JBoarders/CE chassis board.

The ones from this thread:

https://tubeamparchive.com/viewtopic.php?f=5&t=29630

The main board is fine, but all of the rest are nothing like (from what I could see) the boards in #124 and I had to rebuild them all based on the corrected layouts from that board.

A simple example would be the relay boards, see the two here and how they differ:

RelayNon124.PNG

relaySupply.PNG

one is a voltage doubler, the other doesn't seem to be. ONe uses 2 diodes the otehr 4, one uses 3 caps the otehr 2. very different circuits and I didn't see an easy way to mimic them.

On top of it for my build the chassis is much more shallow than the dumble chassis (Fender Bassman 100 chassis) so I had to redo the layout to be longer and more narrow.