1967 Super Bass Build

[Danhalen]

All gone now
I have a 64 JTM45, 65 JTM45, early 69 JMP50, early 45 clone, 50w 2 in 1, 68 BB combo, 18w Trem comb, 18w TMBEF86 and an 18w head, 45/100 JH clone. A few Oranges (30, 50, 100 and a couple of OR120s), Selmer TnB 50 MkII, plus some projects to finish (DR103, JMP50, JMP100) but no 67s left.

Oh, I didn't expect to hear that! I seem to recall you saying that you used your 45/100 much more though. You've got some great stuff to work with. Those original JTM45's must be great.

[Danhalen]

I just ordered my transformers from Marstran! I decided to go with the 1202-132 OT.

Neil in the end I have decided to take your advice and build a single rectifier 10000 series! I changed my mind about 4 times, but I am excited to be finally getting started! Kats, our builds are going to be a lot more similar now

I have a feeling that a Black Flag is in my future, but who knows. This one will keep me busy for a while... I am going to start collecting my parts. Making a Valvestorm order tomorrow

[kats]

Cool. My OT arrives tomorrow so mine will be done in a few days. I’ll let you know how it turned out. Can’t post clips here but I have a build thread going on at the marshall forum:

http://www.marshallforum.com/threads/la ... ld.106436/

One tip. If you order the ‘68 kit from valve storm they only give you 2w metal oxide resistors for some of the long leads required for the build. I subbed them out with some AB carbon comp long leads. A couple of 820r, the NFB resistor and a 100k.

Also make sure they throw in cap/resistor for the 67 tone stack. It changed in ‘68.

[kats]

Ps, I also hummed and hawed about doing the duel rectifier set up. I din’t think it would be that much of a PITA to build a separate power board and sub it in “just to see”. I might do that some day.

[kats]

Heads Up!

The Marstran OT bolt pattern does not align with the Valvestorm '68 chassis. Perhaps you can get them to do the pattern specifically for that OT.

If not, I was able to get a clean install without the previous holes showing.

[Danhalen]

Oh! Thanks for the heads up about that! That is a good tip. I have been back and forth with Robert a couple of times about some details, so I can still ask him about that, my stuff has not shipped yet.

Glad to hear that the install still worked out for you though. Thanks for the other suggestions too. I am going to get a few CC resistors for sure. I am going for some other NOS bits too, going to use mustard caps on this build and I think NOS filter caps too.

P.S. I'll get around to responding to your comments re: recording stuff eventually!

[Danhalen]

Just thought of a transformer question: What gauge of wire is best/safest to bridge the secondaries on the 1203-80 PT with the dual taps?

[kats]

I’m not sure that it matters. Since the CT of the secondaries is going to the mains cap I figure I could have the hookup wire go through both lugs. (Currently I have 18g bridging it, but I wondered why? )

[neikeel]

Heads Up!

The Marstran OT bolt pattern does not align with the Valvestorm '68 chassis. Perhaps you can get them to do the pattern specifically for that OT.

If not, I was able to get a clean install without the previous holes showing.

Funnily enough I had two original 10 series’s split cathode amps both with Dagnals but clearly originally punched for 2” Drakes but hand drilled for C1998 Dagnalls.

[Roe]

Roe, I am curious why you prefer the slightly lower preamp filtering in this amp? Does it soften the transients, or make high notes a bit smoother? Or is it more of a feel thing?

22uf is more than sufficient in the preamp.the power amp matter more imho

[kats]

Heads Up!

The Marstran OT bolt pattern does not align with the Valvestorm '68 chassis. Perhaps you can get them to do the pattern specifically for that OT.

If not, I was able to get a clean install without the previous holes showing.

Funnily enough I had two original 10 series’s split cathode amps both with Dagnals but clearly originally punched for 2” Drakes but hand drilled for C1998 Dagnalls.

That is funny! It seems no matter how you screw up a clone, you can find an original example of the same variation

[kats]

And Danhalen, here’s a PSI.

Double check the colour codes of your transformers if you have any issues. I racked my brains dicking around with this build for 3 days only to find out the OT secondaries were colour coded incorrectly.

Amp is done - I really like it. I put a switchable 4700pf bright cap on it so I can go between SB/SL. I love the feature. I can’t decide what I like better. The extra gain is a riot, but it’s a bit of a one trick pony like that - so being able to go to SB spec is really handy.

[Danhalen]

Sweet! Do you like it better than your JTM 45? Maybe it's too soon to say...

And thanks for the tip, I will watch out for mislabeled transformer wires! I asked Robert about the Drake transformer drilling too, I'll see what he says.

I put in my Valvestorm order on Friday, after some back and forth during the week with Robert. I have to say, great service from Valvestorm so far. No surprise though really, MetroAmp was always top notch too, back when George was still doing the kits. I managed to get everything from him actually, other than Transformers. He was out of stock of .022 mustard caps, so initially I'll have .1 mustards and synergy Royal mustard .022 caps. Might look a bit goofy, but I care about the sound most of all. Maybe I'll swap them out eventually or if it sounds good, I might just leave it alone. Edit: Already found some .022 mustards! I have Silver micas for the tone stack and mixer bypass for now, but when I track down some nos ceramic caps, I'll probably swap those out. I have cc resistors for the positions recommended by George, but I am still missing 2 x 820ohm.

Getting excited!

[Danhalen]

Funnily enough I had two original 10 series’s split cathode amps both with Dagnals but clearly originally punched for 2” Drakes but hand drilled for C1998 Dagnalls.

Ha!

22uf is more than sufficient in the preamp.the power amp matter more imho

Interesting, ok cool thanks.

[kats]

Sweet! Do you like it better than your JTM 45? Maybe it's too soon to say...

Not too soon at all, the differences are apparent. Ultimately for me it comes down to the fact that I like 100 watt amps better than 50 or lower. It's like you get an extra octave/girth/bigger what ever term you like. Hiwatts, same thing - the 50s just don't have the "strength" of a 100.

Specifically though, I like the dirty tones on both amps - maybe a little more on the 100, especially with the bright cap. However, the cleans on the Jtm45 (GEC KT66's) are unbeatable -just shimmery, the amp cleans up much better than the 100. I know for my tastes I'd prefer the 45/100 over the 45. Might even like it better than the "67" although I imagine that I could not get rid of either.

Although I'm mostly LP guy, the Strat sounded fantastic through the 67 as well. It's really a full sounding amp.