New 700b WOPL build... blowing fuse 2 on left backplane

ok - went back in, reattached D52L. Pulled cathode of zener D51L.

Left Side
20 V AC
+15VL: +16.3 V DC
-15VL: -16.4 V DC

Right Side
20 V AC
+15VR: +11.7 V DC
-15VR: -11.8 V DC

Dialed up Variac to 40V AC

Heard a small pop... wisp of smoke coming from VR51L. Powered down. Fuses still intact.
 
That would say that the zener was shorted and VR51L was bad.

I am concerned about the +15V regulation on the left channel as well since you are overvoltage at 16.3V at 20VAC in. But then again you removed the load from that regulator so may not be fair.
 
Hi guys - sorry, fighting a head cold this past week.

Thank you Joe, got the replacement parts installed. Also redid basically all my wiring to clean things up nicely. Biased both sides to 365 mV DC after letting it idle for ~30 minutes or so, and hooked up to a PL 2000 pre. Using some HPM-100 test speakers at the moment, very, very happy. These WOPL'ed 700b's are simply amazing.

Hoping to track down a nice set of rack handles for this, as well as waiting on some of the Belden wiring to replace the black signal cables to/from the faceplate attenuators.

Thanks for all the helpful feedback and support guys, I really do appreciate it!

A couple pics:
 

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How nice do the handles have to be? I have some from the Aerosmith B's ..
 
laatsch55 said:
How nice do the handles have to be? I have some from the Aerosmith B's ..
Click to expand...

In all honesty, I'll be on the lookout for some real clean ones. Reason being is I'd like to rack this amp up next to my prior 700b build. One day, just for kicks, I think I'd like to try bi-amping some appropriate speakers, lol. Don't know if any of you maniacs have tried that yet... I suspect someone has.
 
Sure have, tri-amped my K's once. Had a pair of Heresy's on top of each K, and a D9 in front of each K.
3-400's and 2-700's...it got loud...
I have some pretty shiny handles too bud. Just wondered how good you needed..
 
Did everybody eat up their stash of handles already??? Maybe we should get some more machined.
 
Well, I definitely used all of mine. Can't afford to do another batch. Specially since the mortgage guy busted me out on my secret account.
 
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dtafil said:
In all honesty, I'll be on the lookout for some real clean ones. Reason being is I'd like to rack this amp up next to my prior 700b build. One day, just for kicks, I think I'd like to try bi-amping some appropriate speakers, lol. Don't know if any of you maniacs have tried that yet... I suspect someone has.
Click to expand...
I run bi amp on the house system, quad amp on the shop system. Highly recommend use of an “active line level crossover” which will split you frequencies before the amps. This saves amp power by not amplifying signals you will later take out by passive crossovers. Currently in the house system I have a monster carver PT-2400 running 80hz and down then a 700 series one running My three way cabinets 80hz and up. Highs are cut from the carver and lows from the 700/1 at line level with a slope of 24dB/oct, then the 700/1 feeds 80hz and up into standard passive crossovers to feed the mid bass/mids and tweets. Planning to add my 400/1 and split three ways at line level eventually, with the 700/1 running mid bass and the 400/1 handling the mids and tweets. The mid/tweet split will be the only passive crossover left in the system, everything else filtered at line level.
 
AngrySailor said:
I run bi amp on the house system, quad amp on the shop system. Highly recommend use of an “active line level crossover” which will split you frequencies before the amps. This saves amp power by not amplifying signals you will later take out by passive crossovers. Currently in the house system I have a monster carver PT-2400 running 80hz and down then a 700 series one running My three way cabinets 80hz and up. Highs are cut from the carver and lows from the 700/1 at line level with a slope of 24dB/oct, then the 700/1 feeds 80hz and up into standard passive crossovers to feed the mid bass/mids and tweets. Planning to add my 400/1 and split three ways at line level eventually, with the 700/1 running mid bass and the 400/1 handling the mids and tweets. The mid/tweet split will be the only passive crossover left in the system, everything else filtered at line level.
Click to expand...

Sweet !

What are you using for the crossover ?
I'm currently running a 3 way system with a 700B and 2 400's.. A minidsp 4x10 HD handles the Fq's ....
 
Mohawk said:
Sweet !

What are you using for the crossover ?
I'm currently running a 3 way system with a 700B and 2 400's.. A minidsp 4x10 HD handles the Fq's ....
Click to expand...
Got a couple, all analog. A DOD, Alto, Alesis kicking around somewhere and a China Rockville unit. Looking for an Ashly to match my Eq...
 
Check the bay for an Ashly crossover. Not always on, but set a notice email in eBay and you’ll get one soon.
 
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