ShortScale.org

very excite. it sounds different enough from my other plexi that i've still got that "new amp" feeling despite the identical control lay-out. demos to follow.

basically we've got some seriously thick 'n' chewey chunk on vol II and a bright spiky attack on vol I. the crunch on vol I is probably immense, but the amp is simply too loud at the mo for me to crank the bright channel and be happy afterwards. vol II breaks up pretty quick and would make that "knackered dude" from the gearwire Tiny Terror video jizz his pantalons.


what remains:

• ordered a gold-screened plexi-size marshall logo out of boredom, but it's not guaranteed to go on... still deciding.
  
  putting ohm selector right-side up (no comment for now )
  
  need some sort of cheap attenuator... am currently in the posession of a marshall powerbrake schematic, but it's got some pricey parts. i've only opened this thing up into heavy gain territory once and it was almost too loud to hear.

dad and I overlooked some things since we were working upside down... the biasing stage was gut-wrenching as we discovered major mistakes at that time while risking 500 volts up the fingers. the mains switch was upside down, for one... wrong two legs of the bias pot were bridged, and we'd left out a resistor. it cost us an extra day. and the ohm selector I've kind-of/not-really explained... that was just a silly mistake, we installed it so we could read the numbers, forgetting the chassis was upside down. we had a laugh about it but those wires are so stiff that we can't simply flip it and it'll have to be redone later.

also, the metroamp dude's guide is a little bit crap. he obviously knows his stuff, but he forgot to mention certain things and gave incorrect instructions at a couple of key stages (just slips of the tongue, really... "pin 3" instead of "pin 5," naming the wrong value component, just showing a picture of something without explaining it, etc... i can definately say that if you don't already more-or-less know the plexi circuit or can figure out an amp just by looking at it, you'd have a REAL hard time with one of his kits. my dad was a life-saver, he's been building radios since he was 14 and has an electronics degree, but i'm no expert by any means.

so anyway, 1959SLP circuit (1967 marshall super lead). we toyed with both a 100k resistor in the negative feedback stage (like on my superbass) and a 47k, which is what we ended up using. the marshall re-issue of this amp is 3 times as expensive as what we ended up sinking into this project, and i doubt it could possibly sound or look any better, plus we had loads of fun every time we worked on it, so i'm pretty psyched about it. CUSTOM BUILT MARSHALL, A LA THE ICEMAN!!



starting the heater wiring (the red and black braid at the back, soldered to all the tube sockets along the way, what a bitch!)



when i started the board


the next day while i was at a doc's appointment my dad got the lone capacitor we were missing and we bombed through the rest of the board when i got home. this is when we started to get antsy to HEAR it.


i can't believe the "orange drop" was a "leftover"


NUMBER 5 IS ALIVE!!!! NEED INPUT!


"What do you mean upside-dow---OH BOLLOCKS."



The Super Pat? "1959slp clone?" Laney-Raper? they all sound so clinical.

Absolutely cool!

Looks absolutely fantastic

That is awesome. I'm so proud of you and jealous as well. You've done an excellent job and should be proud 'o yourself.

I bet it sounds immense, can't wait for the clips. Maybe look into a hotplate?

Now you need to take a white spray can to your cabinet to complete the look. That thing looks amazing, and I'm sure it sounds even more amazing. Your own handwired amp, that takes mojo to the next level.

Soooooo cool.

A handmade, point to point Plexi clone that you built with your dad? That sounds like one of the all-time most satisfying projects. Looks fucking awesome.

CLIPS! WE NEED CLIPS!

Phenomenal. Glad you two are still alive as well.

Blow our ears out sometime soon, please.

so rad. i wish i had those skills!

That is awesome!!! I wish I could build an amp. I wish I could build anything.

Thats awesome dude! Congrats!

thanks for the props, dudes. clips and probably a vid are coming this week.

a THD hotplate is exactly what i was thinking Mike. the powerbrake is far too dear for me, in fact i'm still looking out for slightly cheaper alternatives to the THD, even. between this amp and the impending music festival season, i'm pretty damn broke!

my dad said we could install a master volume in one of the speaker outputs temporarily, might do that for the sake of bedroom testing. right now i'm leafing through a marshall circuit mods tutorial for the non-mv models... some interesting possibilities. i'm glad i have a nice amp that i'm not afraid to dick about with.

How about a PPIMV?

I think Weber make an attenuator that's chepaer than a plate - minimass or something?

Mike wrote:How about a PPIMV?

I think Weber make an attenuator that's chepaer than a plate - minimass or something?

the Webers are the cheapest, thanks for the heads up on that one.. but i'd need the Mass to get a 100w version, which'll still be $225. i'll probably go with either that or the THD, though Gibson actually make a hotplate identical to the thd's (same casing) with an XLR line-out for the same price ($300).

my superbass has a ppimv added in a push/pull pot... very useful. i'd do that if i had an extra hole somewhere, right now it looks like i'd be drilling for a knob on the back panel, which would be cumbersome to reach around for/look at. the guy who did it to my superbass just moved the mains lamp and put it there (i remember i wondered at first what this mysterious "indicator control" was before i tried out the amp).

haha.. Hmm this must adjust how "on" the amplifier is.

Attenuators are expensive, but I'd be scared to make my own seeingas teh test process is "oh the transformer melted, I guess I screwed up". Think the Gibson plate or the Mass might be the way forward

hahaha, this would be perfect:

That amp looks awesome....

haha.. how awesome is that?

The one thing I'm unsure of with Power Brakes is their lack of tone controls, seeing as attenuation has a big effect on trebs and bass.

Mike wrote:haha.. how awesome is that?

The one thing I'm unsure of with Power Brakes is their lack of tone controls, seeing as attenuation has a big effect on trebs and bass.

yeah but i've heard from some reviews that the power brake has less tonal influence on a marshall head than the other leading attenuators. i actually only recently noticed the weber's "tone stack" and almost feel like it's them admitting the thing is going to compress the sex out of my tone... but i've heard horror stories about each and every one of these things. i'll probably just keep reading reviews until i've got a couple hundred bucks saved up and then hit up ebay.

the thing actually does sound really good clean n' gritty (the low volumes) so i'll knock up some preliminary samples. the differences between all my different guitars are so apparent it's crazy. raw power.

Awesome. looking forward to it.

An attenuator is kinda a must have on an amp like yours, I only own Master Volume amps so it's a little less of an issue but maybe somthing I might get in the future. ANd yeah the controls make me a little icky too.