68 12,000 with 2" high impedance OT

[vanhalen5150]

If you have any noise problems, you may have to put your OT secondaries between V7 and V6. Having both primaries and secondaries close going between V6 and V5 can cause noise sometimes.

[julkke]

Good point but I doubt it. He has both primaries and secondaries well twisted and not running THAT close together. I'd think it's fine.

[emmjaydubya]

Thanks for the complements!

If you have any noise problems, you may have to put your OT secondaries between V7 and V6. Having both primaries and secondaries close going between V6 and V5 can cause noise sometimes.

That's interesting, I don't think I've seen any builds with the OT wires separated that way. Have you built and amp like this? I guess I missed it, if it ends up noisy then thats the first place I'll look. I've left enough wire under the pot-side of both boards so they can be lifted for corrections.

Speaking of the board, I've been wiring it and putting it together, it's looking pretty sick!!

[HTH]

Good idea on the primary taps on a strip, I did the same thing on an old amp...

[Strat78]

George wires his primary taps this way too on his 10,000 series builds. Looking at pics of vintage amps they seem to place the tag boards at a right angle to where the taps come out of the PT.

[emmjaydubya]

Board is almost done, I'm still waiting on a few more Iskras and the choke before I wire it in. Thought I'd post a pic anyway:

[rgorke]

Board is almost done, I'm still waiting on a few more Iskras and the choke before I wire it in. Thought I'd post a pic anyway:

That looks Terrific!! Even the hard to find 100k Iskras...do you have a good source?

[emmjaydubya]

Thanks, but sadly, no. A one time buy from a guy here on the board. I think he bought quite a few at once and he wanted to recoup some of his money, but he's holding on to rest of them, and I sure can't blame him. I was just glad I could get six 100k in one place, including the NFB! I thought I was gonna have about half and half Iskras/Pihers but I kept lucking out and getting ahold of more Iskras, hopefully the only Piher will be the 8.2k. The last trades I did were a total fluke, got all the rest of the values I needed.

Of course I say that, but they're not in my hand yet!

[BoogieEngineer]

Board is almost done, I'm still waiting on a few more Iskras and the choke before I wire it in. Thought I'd post a pic anyway:

This is one of the most beautiful boards I have ever seen. Congrats! I bet it will sound heavenly

[julkke]

Very lovely looking board!

[Strat78]

Looks great but Pihers are more accurate for that board and turrets, I'll trade you a full set of Pihers for your Iskras. I've been looking for 100k Iskras for about four years now, almost got those six that you have. If you find an 8.2k Iskra then I'll really through in the towel. Looking forward to seeing this build finished, but there is no hurry, better to do it right the first time around. Please no ppimv!

[BoogieEngineer]

Please no ppimv!

What is wrong with PPIMV? I've been using it with great result. You use an attenuator?

[emmjaydubya]

Looks great but Pihers are more accurate for that board and turrets, I'll trade you a full set of Pihers for your Iskras.

Haha deal!!! I'll tell you what, how 'bout we just trade boards, that seems simpler, wouldn't you say? I fully realize that getting those 100k was just pure blind dumb luck. Right place, right time, not to mention the seller's generosity for letting them go. Same thing with the .068 mustard and the 560pf RS. Don't worry though, I paid GOOD money for all of those things so I'll spare you the 'and I got a killer deal' routine. I won't hold my breath for an 8.2 k though, I think my luck is running out.

Please no ppimv!

Do you see any holes drilled in the back of my chassis?!? No way!

[BoogieEngineer]

Someone please tell me what is wrong with PPIMV. I've got the mod all over my builds.

[emmjaydubya]

No offense intended, it's just not for me. There is nothing as awesomely dangerous as a 100 watter giving all it has and there is a purity about it that appeals to me. That's why I wanted to build this amp, kinda like controlling the uncontrollable. A master volume is contrary to that whole idea, like neutering something that's wild and free. Ha, maybe I've had a few too many beers tonight.

I plan on exploring the attenuation route myself, I'm hoping there are some cool things around the corner with stuff coming out, maybe even exploring a DIY unit. Along with a Variac I'm really optomistic that I can gig with this amp without a master volume, call me crazy.