Zach's 700B Thread

Zach C.

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Well, I definitely was, but not now.

At least I had the other units, and had the new OP amps laatch recommended for my 3300II. So, not only did I still have stylin' gear to listen to, but also had a cool upgrade to make me feel better about the suck that was the 4000/ 700B.

:)

Zach
Well, I didn't intend to orphan this thread...meant to leave an away message...forgot...oops.

Anyway, I finally got a chance to spend some time on this again, and I've got it up and running now. Yay!

It looks like my distortion was coming from a bad connection on the back plane. I say looks like, because I changed the pre-drivers at the same time that I re-mounted all of the T03 devices- they all had silpads, and I switched to mica. One of the pre-drivers seemed a bit funny when I was doing basic resistance checks, so I bought some MJ15024to use there, knowing that d3imlay had used these with success with the 2sd555 as drivers, which I already have. Now that I've changed them out, I can't find what I thought was weird- they test fine. Odd

I still have some stuff to do, but it's working. Need to do some more rewiring, since I still have some (substantial) hum when the face plate is ungrounded. Need to install the WOPL control board. Gotta get something done with the lamps, since a few are burnt out. There's some cosmetics. etc. etc. etc.

I think I'll listen to it as is for a while. I need to switch back and forth with my PL300 II to convince myself that I really am hearing the differences that I think I'm hearing. I had expected better bass quality at higher SPL's when the 300's power supply is taxed, but was quite surprised to find how much better (tighter, more detailed) it seems even at normal levels. Maybe I'm fooling myself (all that work must be rewarded!), but at this point it sure seems real.

I had not expected that kind of difference. Tubes vs solid state? Sure, it's gonna sound much tighter. From one PL amp to another...holy wow!

~Great~ I was happily convinced that within their limits, most A/B SS amps sound more or less mostly the same. Well, maybe not.

At any rate, thanks a bunch to all who helped!

Zach
 

laatsch55

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Halfbiass...Electron Herder and Backass Woof
The difference between a White Oaked 700 and a stock one is even more pronounced, then when you go fully comp it's even better.
 

Zach C.

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The difference between a White Oaked 700 and a stock one is even more pronounced, then when you go fully comp it's even better.
The WO control board is stuffed and ready to drop in after I get a good feel for how it sounds in this configuration.

I don't think full comp is in the future for this amp, at least not the near future- too much work. And, even if a backplane board becomes available, I've got so much time in replacing all of the T03 sockets in this thing. I'd hate to think I did all of that just to tear it out again. Maybe later.

Regardless, it's awesome!

It keeps making me want to try to blow it up, but for whatever reason, the wife is always here to grouse about it. She likes loud, but...

And, I've barely been past 1/2 on the preamp so far.
 
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