Dirty Harry 2

[erwin_ve]

Let's start 2021 with a nice amp!
Last year I build Dirty Harry which was a kind of Jose mod Marshall. https://ampgarage.com/forum/viewtopic.php?f=9&t=33668

I really liked I could get from clean to dirty to metal with the same tonestack setting but different gain, volume and master settings.
So why not switchable pots? Made a pcb design, a frontplate design and some other goodies for the looks. I might get a less mirror like faceplate, with a more brushed alu look.
Work in progress.

[ChopSauce]

Would you mind telling me which resistors are these?

[erwin_ve]

Would you mind telling me which resistors are these?

You mean the brands: Nos Beyschlag, Piher, Draloric and a newer Xicon CF and Dale Rn65d somewhere.

[erwin_ve]

After waiting for a PT more than 1,5 months I finally finished the amp.
Testing went well, no plops when switching the relay.
In my previous build I had a different brand of silver mica which was sold out this time, the previous ones sound better so they are gonna be changed.
No dc heaters this time which also went well.
Only biggie is the frontplate lettering on the edges are not as visible due to the cab. Prototype update

I'm happy with the outcome for this proto.
Now get me a gig in these strange times!

[ChopSauce]

This second one is more sober, yet looking at least as efficient ...

Like french use to say (translated version) "you already told too much or not enough" about silver mica cap brands ...

[Reeltarded]

VERY cool!

[erwin_ve]

This second one is more sober, yet looking at least as efficient ...

Like french use to say (translated version) "you already told too much or not enough" about silver mica cap brands ...

Sober yes. A Jtm45 chassis was used, that chassis is smaller with more knobs so less room for fancy faceplate items.

That French saying : I guess there is more to share on the silver mica. The previous Dirty Harry had CD 19 series silver mica. This time I had Tad and for the 2700p bright some unknown brand blue color sm. That blue one has real nasty overtones.
Conclusion is that the yellow sm cd19 is a better choice, no weird overtones, just a good cap.

[erwin_ve]

VERY cool!

Thank you Miles:
I had so much fun reading your posts and besides the fun there actually were quite a lot of informative posts on Marshall stuff that I tried. Clippers were somewhat new to me and your posts helped a lot !

Erwin

[ChopSauce]

Thanks!

[Reeltarded]

VERY cool!

Thank you Miles:
I had so much fun reading your posts and besides the fun there actually were quite a lot of informative posts on Marshall stuff that I tried. Clippers were somewhat new to me and your posts helped a lot !

Erwin

Your choice of the 45 format is loveable. That is most of what I have done.. the silver mica question is also revealing. (or in this case stringent and splatty) I love that amp. I would love to hear it mid volume where the output is awake but the frontend can do all its things.

The thing about the eq curve holding through gain settings is my target. I like it when everything about the amp stays put.

Good stuff. Glad something I did helped you too.

[erwin_ve]

CD19 silver mica caps as bright caps are in, massive difference!
Lowered the B4 stage voltage (for the entrance triode and the following triode stage) which make it a little juicier to play.
Balance pot for the PI set, bias is about 60% at 449v.
Even on low volume the amp has nice sustain and feedback abilities, almost like a Dumble

[Reeltarded]

we are all moving toward infinity and the evolution of all amps ends at a singularity

im not kidding

[erwin_ve]

we are all moving toward infinity and the evolution of all amps ends at a singularity

im not kidding

Im fine with that as long as it doesnt end with a big bang.

[Reeltarded]

I hate to tell you.. in 10^70 years, when all of the entropy has been swallowed by the ultra massive black holes, at a time when the black holes have evaporated completely as simple ionized particles speeding through virtual nothingness at near the speed of light, and in a kind of region that comes to an absolute ground state.. those particles entering those regions are now in violation of the collapsed second law of thermo dynamics, blowing through an existential speed trap where the limit is nearer to zero than 300,000km/ps...

i have other news that is pretty good though.. i saved over 300% by firing geico.

[didit]

we are all moving toward infinity and the evolution of all amps ends at a singularity

im not kidding

Im fine with that as long as it doesnt end with a big bang.

Space-time gets well & truly dilated; such that you really won't notice all, and so won't care.

..