Which tonestack?

[Tarkus]

As the Dumble ODS preamps have a bewildering array of different versions/circuits (especially the tone stack), can I ask if there is a consensus of opinion on which one is the best?

I know this is a bit of a loaded question and depends on a lot of variables. But if I was looking for something like a Blackface Twin Reverb clean sound, only more so, (with a bit of blues crunch but not so much Marshall overdrive) were would I start?

It seems that when ever Mr. Dumble got access to his existing amps, he would "update" the earlier circuits with what ever was the latest version at the time. This would suggest that he considered each modification to be an improvement, which itself would suggest that the latest version is the best one (which would simplify choice) is this the case?

So any suggestions on which versions (with v numbers, and where to find schematics if pos) would be greatly appreciated.

[xtian]

I think, with Howard, it was more about, which sound suits the player.

If you like the blackface sound, you will like Jazz mode (look at #183). For more Marshall style, look at Bluesmaster.

[talbany]

As the Dumble ODS preamps have a bewildering array of different versions/circuits (especially the tone stack),

Really there are only 3 to choose from
1.Classic
2.Skyliner/2nd Generation
3.Bluesmaster

But if I was looking for something like a Blackface Twin Reverb clean sound, only more so, (with a bit of blues crunch but not so much Marshall overdrive) were would I start?

Low Plate "Classic"

"It seems that whenever Mr. Dumble got access to his existing amps, he would "update" the earlier circuits with whatever was the latest version at the time. This would suggest that he considered each modification to be an improvement, which itself would suggest that the latest version is the best one (which would simplify choice) is this the case?

Not always. It would, of course, depend on the player's needs. I cannot see where if an owner of an ODS liked the sound of his or her amp would want to or be forced to change it simply because it was an update. I am sure Dumble would explain the changes and if the owner wanted the updates Dumble would then do them. Probably for a price. it's not a smartphone

So any suggestions on which versions (with v numbers, and where to find schematics if pos) would be greatly appreciated.

In the files section "124 Low Plate Classic" is the one you want and Pay attention to parts like resistor and capacitor types. For instance, a BF Fender amp has a ceramic cap so use a ceramic cap etc etc. BTW. All ODS's use metal film's on the Plates (If that is what you're building?)
https://ampgarage.com/forum/viewtopic.php?f=5&t=12872

Tony

[donvan]

Really there are only 3 to choose from
1.Classic
2.Skyliner/2nd Generation
3.Bluesmaster

Hi Tony,
I'm curious why you left out the Ripper. Is the Ripper tone stack similar to one of the other 3?

Thanks,
Don

[talbany]

Really there are only 3 to choose from
1.Classic
2.Skyliner/2nd Generation
3.Bluesmaster

Hi Tony,
I'm curious why you left out the Ripper. Is the Ripper tone stack similar to one of the other 3?

Thanks,
Don

I don't know? for certain 100% only rumors. If someone can post me a schematic (an accurate one) I'll be glad to tell you .If there was a gun to my head I would say Bluesmaster, given the " Ripper" is based on a Marshall thang!

Tony

[Charlie Wilson]

Hello, #189 is a Ripper with a skyline. That was the tonestack the owner wanted. I think most Rippers have a Bluesmaster.
https://www.youtube.com/watch?v=Sbo15gAgcsY
CW

[donvan]

Hello, #189 is a Ripper with a skyline. That was the tonestack the owner wanted. I think most Rippers have a Bluesmaster.

Thanks Charlie.
My understanding is that Ripper refers to the clean section of the preamp. Is that correct?
If it is correct and a Ripper can have different tone stacks then what makes it a Ripper? I always incorrectly assumed it was the tone stack. Is it just the plate resistor values and cathode bypass component values?

Thanks,
Don

[Charlie Wilson]

No Ripper is the Cathode follower OD section. Similar to a JCM800.
CW

[donvan]

No Ripper is the Cathode follower OD section. Similar to a JCM800.
CW

Thanks Charlie. Man, am I confused.
I got my information from an interview with Brandon. His info on this site always seems excellent in my opinion. And yours does as well, Charlie.
Can you help me clear this up?

So there is an article here: http://gjd.guitaraffair.com/insiders/11 ... ery-dumble
It's called: Amp Insider with Brandon Montgomery: The Dumble Zone

He says this:
"There are 4 basic voicings of the clean channel. Classic, Skyliner, Bluesmaster, and the Ripper. There are also a few different overdrive circuits. The Standard, HRM (Hot Rubber Monkey), and another more obscure circuit known as the MegaPlex. I believe The MegaPlex circuit really only exists in the Ripper model."

So he is calling the OD section of a Ripper a MegaPlex but he is also saying that the Ripper is a clean channel voicing.

[Charlie Wilson]

Hello, well Brandon is the man but in this case I have to disagree. The photos of #189 in the file section are of a Ripper that I have been in and know it is a Skyline. The attached schematic of a Ripper was posted by Gary at Glasworks and it comes from someone who was also inside a Ripper. It has a Bluesmaster clean section. As far as the Megaplex goes. There are only a couple of those around and I know one of the owners. The funny thing is a made him a Dumbleator and he called me up and asked were does it go in the amp. I was a bit confused until I realized there are no preamp out/power amp in jacks on the amp.
CW

[norburybrook]

Can I jump in here and ask, is Larry Carlton's amp a ripper?



M

[erwin_ve]

Thank you Charlie for posting the ripper schematic, I have a map on my computer with things posted over the years on #189 but this is different .

Couple of things that jump out: special Air Core inductor from B-17 Intercom system. What does it do? A antenna or a filter? And what size are we talking about?
Plate-cathode is very different.
Od entrance with a HRM entrance and a 270k to earth, never seen before!

[donvan]

Thanks for the info Charlie!

Marcus,
My understanding is that LC plays a Ripper. Does this mean it's time for you to build a new amp?

Erwin,
Near the end of the following thread, this schematic is discussed. Consensus is to leave out the air core inductor.
Also of note is that the power supply to be used is a bluesmaster supply.

https://ampgarage.com/forum/viewtopic.php?f=5&t=27644

[rdodson]

Did anyone ever divulge/figure out what the purpose of the inductor is/was?

Ron

[jcsifu]

I don't remember anyone saying why it is there, but I seem to recall it being a 15MH choke...anyone else remember that?