Dirty Little Monster

[mcrracer]

Go for it and let us know how yours came out.

[KellyBass]

You can bet I will...as I'm sure I'll need some help!

I built the preamp with ol' skool cinches instead of a turret board to make switching things out easy. I'm determined to use the EL34. I'd sure like to use fixed bias, but I'm not too clear on the negative bias supply with my current PT. (190-0-190)

Anyway, I think this thing has great promise!

[mcrracer]

Are you sure that will give you enough plate voltage???

[breakfastbuddy]

well it can be 380vac or 190 vac so it can be enough , 380vac makes around 530 vdc

[KellyBass]

I'm just not sure about using this 190-0-190 PT for this build. Maybe I'll save it for a SE EL84 build or something.

If I do use this trannie, I'll be forced to use a bridge rectifier...which pretty much restricts me to cathode bias. Is my thinking right on this?

My goal is to retain as much as the wreck mojo as I can...just in a single ended design.

Thanks for all your thoughts! I'm kind of new to this amp stuff. I'm just a poor musician who loves to solder!

[dblgun]

This DML thread looks to have just died 12 years ago with what seemed like a great deal of interest. There has since been photos of the real deal, at least of the exterior. Has anyone continued to work on the schematic and/or layout used by Ken? Who has recently built what they consider a great amp from what is known? One has been something I have wanted to dig into for some time and want to start research.

thanks

[Mark]

Without internal pictures of the DLM, it didn’t get up.

“I had the original Dirty Little Monster here for a few months. It had an EL34 output tube and a tiny little output transformer from an old RCA record player.
It had some really cool aspects to it, but didn't blow me away at the time.

Ken had designed an output transformer for it and had some prototypes made. I got my hands on those as well. It's a much bigger transformer (size of a Komet 60W OT) and properly air gapped. It's what's in the amp for sale now.

I built a DLM with the bigger OT, and it sounded much better. Still not quite there yet. I basically just put it aside and revisited it occasionally, constantly tweaking it. Literally worked on it on and off for 10 years.

I really love my current version. Mine is KT88 based. All that's left of the original DLM is the basic topology. It's a really cool, classic sounding amp that's ideal for studio use. It can get about as loud as a Tweed Deluxe, so I have used it on smaller gigs with great results as well.

Releasing it as a production amp would be difficult. The parts count, labor, build complexity, even transformer cost is about the same as a K60. Don't know if there's a market for a single ended 15W amp that costs as much as a K60.

P.S.:
Ken gave a schematic to some friends. It's hand drawn and dated 1999. I think Dr. Z built some amps for Joe Walsh off of it. The schematic is somewhat similar to the real Ken built DLM, but it's not the same.

Hogy, Komet Amplification.”

https://youtu.be/5vKnBBy_BzM

[dblgun]

Without internal pictures of the DLM, it didn’t get up.

That is unfortunate, there appeared to be quite a bit of interest at one time. The proposed "potential" schematics are interesting and varied. Some of those here put in quite a bit of work on them. I think I'm going to continue working towards coming up with something.

In looking at the photos of the known example I find it interesting a can capacitor was used as part of the filtering. Ken seems to have deviated from the "stacked" caps he normally fitted into the BUD chassis.

[Mark]

Have you seen the AX-84 stuff?

https://ax84.com/archive/ax84.com/stati ... 101004.pdf

https://www.hammfg.com/files/parts/pdf/125ESE.pdf

https://www.hammfg.com/electronics/tran ... ic/200.pdf

The 270EX, 270FX and 270 HX are all good options.

https://youtu.be/u_MBHfKI3cw

[dblgun]

Hey Mark,
I have seen the AX-84 schematic before but this is a great set of all the documents in one place, thanks.