My 5w DLM Schematic

[JamesHealey]

Hey guys this is the 5w Dirty Little Monster I built for a friend,
it's trainwreck inspired but it's surely not a true clone by any sense.

But I thought i'd share it and see if anyone here wants to put it together, we've already got a working version of this and it's unreal!

Thanks,
James H

[Structo]

Interesting, I've been thinking about making a small SE amp.

What did you use for transformers?

Also, what is the tube topology as far as V1a V1b, etc.

Is V1 only the first half, then V2 uses both halves?

Thanks!

[Decko]

Hi James,

This looks very interesting. How does it sound with the EL84? Can you post pictures and a sound clip?

Regards,
Decko

[JamesHealey]

I no longer own this amp it was for a friend, but he owns a studio and we're hoping to get some clips made up soon!

The Single EL84 is a great sound it's got tonnes of sparkle and a real grind with some added sweetness from the SE power section.


The Mains transformer was from Ampmaker.com and the Output Transformer was from Astonelectronics.co.uk (5.1k Primary)

[JamesHealey]

I used all original mustard caps and erie electrolytics from the 70s, carbon film resistors through out apart from the 100k anode loads they were carbon composition, Silvered Mica Bright and Tone Treble Caps.

[Structo]

How was the noise level on it?

I see you have referenced the heater center tap to the cathode of the power tube.

Does that help lower the noise floor?

I have seen that done before on cathode biased amps.

Which tube are you using only the one side of?

[JamesHealey]

V2 was the one sided tube.

[Noel Grassy]

I love the sound of these SE EL-84 amps! I shoehorned two 8" AlNiCo speakers under mine and it "brings teh brewtal". Not Metal by a long shot but that chewy calorie rich Blues overdrive that likes Strats & ES-335s. I'm running a single triode in the pre so I dropped all the tone stack stuff in favor of 33n/330pf bypass caps. The silver mica sound heavenly in these SE amps fer sure. I used Pyramid PIO caps from the 50s for the33n.
So as killer as it sounds today I'm subbing in a Si diode string parallel with the 5Y3 for a switchable extra 40volts on my B+. Before tomorrow I'll have the cathode bypass resistors sussed out and on the same switch to keep the wee plate on the EL-84 from turning to ash.

I found a chassis in my treasure chest that sports what looks like some old Hi Fi console's iron, tube bases, etc. Each channel had a pair of EL-84 and a pair of 12AX_. These two OT about twice the size of my SE OT. With two new PT that are of similar B+ potential my stereo rig could be more manageable. Like mounted cabs on swivels that attach to either side of my rolling ATA case. That would put 'em at waist level.

What current does one half of the 12AX7 draw? Man I'd like to cheat that out of my PT for the extra gain stage! Or is it the filament current
that'll put the hurt on a PT? I'd bet it's the latter.
I'll build your design JamesHealey. It might be getting the Mustard massage too if I can source the ones I don't have. What brand did you prefer for the power string filter caps? Thanks for sharing,

Noel Grassy.

[JamesHealey]

I used old stock Erie filter caps from an old Carlsbro head they were still testing with no ripple/leakage.

I used a lot of old parts just scattered around for this build but it was a killer amp! and it's still pride of place in a local studio, im putting a 36w version of this amp into production soon.. but the pre-amp is even further removed from a Trainwreck design.

The OT was 5.1k Primary Impedance and 20w power handling it was very over spec'd for the application but the Impedance was perfect.

The PT was from ampmaker.com it was his 5w PT.

Cheers.