Jasmine Rocks

WOPL Sniffer

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#1
Just finished up a New Build for a customer. Jasmine turned out Very Nice. I just pulled her off the test bench.. Nice and quiet as usual.

Thanks to Joe, she has a new chassis, fins, backplanes, control board, light board... And much more..... Including one of Joes Beautiful faceplates. White Oak Audio Design KICKS ASS!!!! Thanks to his fast shipping, I was able to complete this build in record time.

He likes it so much, I have another of his getting upgraded....




Todd's new WOPL.jpg
 

Netfly

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#3
I'm curious, you seem to like the 700B for your base and they look great. I was wondering about the published S/N difference on the B vs Series II and does that become irrelivant after a rebuild? Was it different output transistors or something else?
 

Northwinds

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#4
I'm curious, you seem to like the 700B for your base and they look great. I was wondering about the published S/N difference on the B vs Series II and does that become irrelivant after a rebuild? Was it different output transistors or something else?
The 700B provides the Class, the series II displays the Balls. Same killer amp
 

Gepetto

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#6
I'm curious, you seem to like the 700B for your base and they look great. I was wondering about the published S/N difference on the B vs Series II and does that become irrelivant after a rebuild? Was it different output transistors or something else?
Same amp. Only noteworthy difference between the two is the cosmetic treatment. Analog vs. Cylon meters and faceplate styling. The Series 2 was a cost reduced 700B.
 

Netfly

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#7
So what accounts for the difference in quoted specs for s/n and power? 100db vs 110db, 345w vs 360w.
 

Gepetto

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#8
So what accounts for the difference in quoted specs for s/n and power? 100db vs 110db, 345w vs 360w.
Beats me, maybe more modern test equipment and the amplifier spec wars that they were faced with at the time...

As Lee, Perry and Jer will tell you, you can make or break that last 10 dB of SNR based on how well you route the wiring within the amplifier chassis. The S2 may have invoked a cleaner input cabling run than the 700B did which makes all the difference in the world. It is a matter of ~360 microvolts at those levels which accounts for such a small difference.
 
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laatsch55

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#11
Just finished up a New Build for a customer. Jasmine turned out Very Nice. I just pulled her off the test bench.. Nice and quiet as usual.

Thanks to Joe, she has a new chassis, fins, backplanes, control board, light board... And much more..... Including one of Joes Beautiful faceplates. White Oak Audio Design KICKS ASS!!!! Thanks to his fast shipping, I was able to complete this build in record time.

He likes it so much, I have another of his getting upgraded....




View attachment 30422

Love that faceplate man!! Pristine!!!!!!!!!!!!!!!!!!!!!!!
 

Gepetto

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#13
Depends entirely on rail voltage.....not all transformers are wound the same...
Whenever you test things like a power amp for publishing specs, you put your best foot forward by bringing out your best lab queens to perform the test on. You can bet that test amp was tweaked to the hilt.
 

Gepetto

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#16
Whenever you test things like a power amp for publishing specs, you put your best foot forward by bringing out your best lab queens to perform the test on. You can bet that test amp was tweaked to the hilt.
Power ratings; the 700B is rated at >345W into 8 ohms, the S2 is rated at 360W into 8 ohms. The power ratings on the S2 are given at 120VAC in. Not stated in the 700B specs but likely a 115VAC input voltage (old school). (achievable output power is proportional to the input AC voltage). In fact, (345/360)*120VAC = 115VAC giving rise to the very strong likelihood that the PL700B was rated at 115VAC instead of the 120VAC that the S2 was rated at.

The SNR ratings on the S2 are nominal and IHF "A"-weighted specs whereas the 700B are not. The 700B ratings are "greater than 100dB" versus nominal for the S2. This "A"-weighting makes a big difference. The residual noise is 120 microvolts "A" weighted for the S2. Lee and I have readily been able to produce 700B specimens with less than 100 microvolts "unweighted" residual noise (these amps sound truly like a black hole).

The long and short of it is that there is a lot to specsmanship so pay careful attention to how spec sheets are written. :) The 700B and 700S2 are the same basic amp.
 
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bill7621

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#18
Why wait? You could be enjoying listening to one rather than lusting over pictures of other peoples. As I was told in the beginning, they seemed expensive until you compare them to amps with with that kind of power. That's when they make you realize they're a bargain no matter how you look at it. Plus, you're getting a custom built amp that'll probably outlast you. Even though it will look similar to others, it'll be one of a kind. I had Perry build me one of the Clair Bros. amps and I've never once regretted it. Mine was a retirement gift to myself. I'm sure any of these guys that build these things would be glad to accommodate you. Heck, you could be enjoying one before Christmas.
 
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