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Phase Linear???

Can anyone please tell me how to contact Dean and Ed? I keep reading so much about them, but can't find any current contact information. Any help would be appreciated.
 
Amongst the self-appointed teenaged stereo "Experts" at McCallie school in Chattanooga in the early Seventies, P/L stuff was held in utter thrall because the 700 supposedly had an output roughly equal to one horsepower.. I think there was an audio boutique on Brainerd Road just past the school that had their gear-I'm SURE they got tired of all the "Experts" making pilgrimages to see/hear the object of their lust/affection/awe...
 
They were good reliable amps and a bargain in their day. I had a collection of ten amps that i just sold last year. Most were early with the Phase Linear logo in handwriting instead of the latter printed logo. If you go looking for one now just make sure that it was not converted to a guitar amp, many were back then, made popular by the Grateful Dead and others.
 
Sandy G said:
Amongst the self-appointed teenaged stereo "Experts" at McCallie school in Chattanooga in the early Seventies, P/L stuff was held in utter thrall because the 700 supposedly had an output roughly equal to one horsepower.. I think there was an audio boutique on Brainerd Road just past the school that had their gear-I'm SURE they got tired of all the "Experts" making pilgrimages to see/hear the object of their lust/affection/awe...
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Actually and recently measured by Laatsch55 at 774 watts/ch into 4 ohms at clipping on a stock unit so actually about 2.07 Hp. Seems they were slightly underrated back in the day!
 
And after pushing past clip a little the AP rolled over to KILOWATTS, kinda cool seeing 1.014KW. And the 700 will drive a 2 ohm load, but LOTS of cooling is needed, if you can stand the squeal of the output stage at 1khz....
 
And that was with both channels loaded and driven....monitored rail voltage at clip into 4 ohms was 79.7 volts DC+/-.. Ac mains droppod from 121 to 118 volts AC and held steady. With a better power supply the 700's would do over 1,000 watts per channel. We're gonna find out sometime this summer as I'm building some scratch built mono blocks based on the White Oak driver boards and new fully comp backplane boards with HUGE outboard power supplies developing 118 volt rails. The entire output section of one 700 will be dedicated to one channel with a total of 22 output devices , Mj21196's, and 21195's...there will be 2--800va toroids and 4--35,000uf/120 volt caps per mono bloc. Ouput should fall between 650-700 watts into 8 ohms and double that into 4 ohms, the power supply should be able to keep up , if not, I will double the transformer count..
 
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laatsch55 said:
If you could keep the rail fuses in...
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If the V/I limiter circuit is functioning they'll operate in constant current. Probably not enough current to actually weld with them. Laatch may want to give it a try and add to his legacy. Would at least make for an intersting pic.
 
d3imlay said:
If the V/I limiter circuit is functioning they'll operate in constant current. Probably not enough current to actually weld with them. Laatch may want to give it a try and add to his legacy. Would at least make for an intersting pic.
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Maybe 18 ga mild steel??? Lots of cooling required. Definitely there are welders plugging into 15 amp circuits/110V that will weld up to 3/16".
 
Is there someone in or around North Carolina that can work on Phase Linear gear? I have a Series II Model 700 amplifier and it works great, but it has a few very minor issues.

There's a slight hisseven with the volume turned all the way off, and nothing attached to the inputs. The hiss gets louder when the two volume pots are turned to half way, and then it starts getting softer again when the volume pots are both at max power. (these are the volume controls on the amp itself). I like to run the amp with the volume pots at half volume, which gives the volume control on the preamp a lot more useful range.

When starting up, there's a louder hiss on the speakers, and it takes a while for it to settle down. Likewise when powering off, I get a hiss a few seconds after shutdown, and sometimes it ends in a slight pop from the speakers. Slight, though.

Really nothing major, but this is an old piece of gear, and I'm sure there are capacitors that need replacing and servicing to be done. I also hear about something called a WOPL for the 700B amps. Mine is a series II though, so I'm not sure a WOPL can be done -- or evne what a WOPL is, to tell the truth.

I'd really rather not ship this behemoth, so someone within a couple hundred miles of Raleigh, NC would be ideal. :)

Charles.
 
Your Ser II can take all the White Oak upgrades, are you the Same ChopperCharles that is on Phoenix?? Shipping is no problem in a specially designed Cabbage Case...Don has a pretty slick method for shipping them too.

The hiss.....Pl had their head up the tushie when doing the grounding on these amps. It can be fixed, but your's doesn't sound like a ground loop, just some flaky front diff transistors...


BTW...a WOPL is a White Oaked Phase Linear...
 
I only heard a 700 once, back in the day.. University of Maryland, Kappa Alpha frat house.. They had one, I dunno what pre they had, & the speaks were big-@zz Cerwin-Vegas, somebody put on "Slow Ride" by Foghat, & Oh. My. Gawd...
 
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