talbany wrote: ↑Sun Feb 27, 2022 12:16 pm

First, it's hard to know exactly what Type of O.D.S circuit you have there with simply one picture of the front. The one identifying factor you do have is it's a "Gold Script" chassis which Dumble used on his 4th/5th/6th "generation" Amps
http://ampgarage.com/forum/viewtopic.ph ... 33#p237433
Here you can find a breakdown in some detail of what exactly is a 4th/5th/6th generation (Including the Bluesmaster)
http://ampgarage.com/forum/viewtopic.ph ... 31#p237431
On top of this Dumble did upgrades to his amps throughout the years so the amp could have started as one version and have been upgraded or converted into another. Dumble also did a 4th generation style with a Music Man (high voltage) output section in the "gold script" chassis.
Unfortunately the only way to know for sure is to talk to the owner, see what he/she knows or is willing to tell you, Get more photos, a serial number, and any other info you can find about the amp, Otherwise it's just a guess.
Dumble considered his amps a one off prototypes custom made for each customer (Some had to submit a recording) and the chassis were basically a platform to build these various models.
BTW. If you can identify what model/ generation it is all the info you need to build it is buried within the Amp garage.
We'll be more than happy to help with all the component stuff
Tony
No totally, I understand that it's unreasonable to ask you to tell me anything about an amp you don't have or haven't worked on. Sorry if it came off that way. I'm just more wondering if it's it possible to make an educated guess or tell based on how it sounds? I don't mind hearing speculations, they're fun of course. There are a few links that I posted underneath the image going to some really incredible sound clips of the amp where it displays quite an exceptional amount of harmonic overtones and whatnot. The thing sounds amazing!
The only info I have from the owner is that it's "from the mid 2000's and not that old" and has 6L6's and is an HRM going into an EV speaker. I honestly don't want to bug him I'm sure he's gotten a ton of DM's about it haha
I'd love to build it but that's probably not going to happen since there's no info about it. I feel like I should build something that's more right up the central alley of what Dumble ODS's are. I know there's no such thing as just a "Dumble ODS" and am aware that they were all custom made with tons of tweaking but I'd love to just build your basic ODS (with regards to what most people on here go for as a first build) so to speak. I've found the best way to learn about something is to start somewhere where everything branches off of (and ask an annoyingly large amount of quetsions to whoever will listen

). But I don't mean necessarily Mr Dumble's branching paths but say within the ampgarage world. There's so much coverage on amp 124 I feel like that's a good place to start? Is there another ODS that is as fully documented as that one? Basically I want to get my feet wet with a proper ODS build and just learn from there by changing it once I have absorbed the design into my psyche so to speak. Yeah I know that sounds weird lol but yeah I'll read the generation identification thread you shared with me and see what's what.
Please forgive me for asking so many annoying questions, I am just excited to participate in this community. I'm quite amazed by Mr Dumble's creations and honestly have an awe of fascination with regards to the way they sound and work. I hope I don't annoy you guys by being so curious.
martin manning wrote: ↑Sun Feb 27, 2022 12:00 pm
My recommendation on component selections is to use new good quality parts, and pay close attention to the values and the materials they are made from. By that I mean use metal film resistors in the locations they are called for, carbon or metal film elsewhere, and capacitors with the specified dielectric type and construction. Certain brands have traditionally been used, such as Dale RN65D resistors for plate loads, and Sprague Orange Drop film/foil for the coupling and tone caps. They are currently in production, and I would stick with those. A brands, they have been bought and sold over the decades, and may not have exactly the same construction as in the past, but the differences are negligible, IMO.
Honestly that was the approach I wanted to take initially but I keep seeing so many people say that the correct parts are what makes the sound of some of these amps and I just want to be able to have that proper Dumble experience when I'm finished you know? I know it sounds kinda snobby but I want to strive for accuracy and "good enough" isn't good enough for me. It doesn't mean I think I'm better or anything offensive like that, it's more that I'll always have that question in the back of my head about how it's "supposed" to sound vs what I've created with new production parts and that will drive me crazy!
If I may ask, what's your reasoning for avoiding the vintage components and suggesting to me that I go with all new stuff? Is it mostly just ease of availability? I kind of enjoy looking for parts to be honest. Even trying to find those sprague 300uF caps was quite a fun journey though I came up with nothing in the end. Before you mentioned it, I had actually discovered the snap in radial caps that fit the bill for the filtering values that Dumble used.
BTW my board set is apparently based on your pdf files according to Amplified Nation so I must thank you for sharing those with us all! Would you be able to take a look at the preamp board I have and tell me what ODS model would work best with the eyelet layout that I believe is of your design?
photo_2022-02-16_16-23-14.jpg
The other boards are not pictured but I have those as well (FET, RECT/BIAS, RELAY POWER)
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