Metropoulos Forum

I was one of the lucky few to score a 68 chassis several months ago during that metro stampede. So here is the build I've just finished thanks to all the guidance/coolness from vhjunkie. I wanted to try a 2" core OT (vs. the 1.5") in this build with stock 68 specs. Larry ground on this and a few CC's in the right places, plus the larger diodes and a little fred too. EH 6ca7's, two NOS Sylvania 12ax7's and one Tungsram in the middle. The grind is there with just the guitar and echoplex into the amp. Bright, raw and stock stock stock!!! Almost.

Edit April 2013: Here is the same amp but with all NOS Iskras and other fun things. Thought this would be a more interesting pic to start the thread.

Sounds great. Are the swamp resistors 1.5k? and I would change the NF resistors to 47k cc.

Here is how I like to wire the boards with everything on the bottom including all the jumpers. These are set up for Larry grounding, plus wiring of the power board for easy cap forming down the road. I put in the lengths for the pre-board wires as well, leaving enough wire on the pots sid of the chassis to be able to lift the board for easy mods.

axeman wrote:Sounds great. Are the swamp resistors 1.5k? and I would change the NF resistors to 47k cc.

Yes, 1.5k. I'm tapping the 4ohm so thats why I have the 100kNFB, but since the amp is so loose on 10 perhaps I should tap the 8ohm and go with a cc 47k there (I'll try the 47 anyway). I want to try a 5H or 7H choke first to see if that tightens things up a bit (That's a mm 3.8 choke now).

i never experience loose with less feedback only more hair. try the 8 ohm for sure.

Is your choke 3H?

axeman wrote:Is your choke 3H?

i use 3 and 7.

Strat78 is your choke 3H?

This build has a mm m-CH Late '60s 100 watt clone 3.8 Henry choke -ha ha, I just had to try it! Mark, I think "hair" rather than loose was the word I was looking for because the bass is actually allot tighter than Georges stock 68 build.

Strat78 wrote:This build has a mm m-CH Late '60s 100 watt clone 3.8 Henry choke -ha ha, I just had to try it! Mark, I think "hair" rather than loose was the word I was looking for because the bass is actually allot tighter than Georges stock 68 build.

I hear ya! so you don't like the 100k/4ohm? i think i prefer the 100k/8ohm myself.

rockstah wrote:

Strat78 wrote:This build has a mm m-CH Late '60s 100 watt clone 3.8 Henry choke -ha ha, I just had to try it! Mark, I think "hair" rather than loose was the word I was looking for because the bass is actually allot tighter than Georges stock 68 build.

I hear ya! so you don't like the 100k/4ohm? i think i prefer the 100k/8ohm myself.

I'm trying Freedmans specs at this point except for the 50/50 PI cap. I have a single 32up in there right now. I'm liking the ability to really push the amp into saturation just by slaming the strings, still I think there is a little too much squish right now, but perhaps that is because the pickup is a hot 14k mighty mite. It's hard to know where to begin to reduce that squish: 7H choke, 100uf PI, 8ohm tap!? Will all these things get me there with slightly different outcomesThis set up might be perfect with a super 70's.

Strat78 wrote:

rockstah wrote:

Strat78 wrote:This build has a mm m-CH Late '60s 100 watt clone 3.8 Henry choke -ha ha, I just had to try it! Mark, I think "hair" rather than loose was the word I was looking for because the bass is actually allot tighter than Georges stock 68 build.

I hear ya! so you don't like the 100k/4ohm? i think i prefer the 100k/8ohm myself.

I'm trying Freedmans specs at this point except for the 50/50 PI cap. I have a single 32up in there right now. I'm liking the ability to really push the amp into saturation just by slaming the strings, still I think there is a little too much squish right now, but perhaps that is because the pickup is a hot 14k mighty mite. It's hard to know where to begin to reduce that squish: 7H choke, 100uf PI, 8ohm tap!? Will all these things get me there with slightly different outcomesThis set up might be perfect with a super 70's.

very cool. the squish will go with the higher value in the PI. i like 50u here.

Right on....

What is that small square yellow cap laying on the board?

Did you reverse the OT? Greco, right?

Do more clips before you start mucking about so we can hear the changes!

This just made my week.

Great looking amp strat78. Unfortunately I can't listen to the clips ight now.

I was just wondering if someone could fill me in on those diods in the rectifier. Are they just big freds or are they not fast recovery diods? What is the code on those?

Thanks

I like the low end. Tight thump and in your face when you dig in. Nice....Sounds great....I bet in sweetens up more as it breaks in.

sounds killer! nice work!