Larry's Phase Linear 700B

[speakerman1]

Re: Larry's 700B

No no Christmas gift. I am awed at all you have done. I pity the neighbors when it gets home. I hope I have the speakers done. I will think of something you need that I have. On the meter about using them I was talking about the dirty probe. No your not getting my Perpetual Tech gear either. LOL

I want to hear how it holds up to your toys.

Larry

 

[laatsch55]

Re: Larry's 700B

OK, a good transport will do. Gotta work today, but it'll be pushing the Kornerhorns tonight.

 

[speakerman1]

Re: Larry's 700B

I might be able to do that. LOL What size T-shirt do you wear?

Larry

 

[laatsch55]

Re: Larry's 700B

2X, the wife large.

 

[speakerman1]

Re: Larry's 700B

Did Tom get back to you?

Larry

 

[laatsch55]

Re: Larry's 700B

No Larry not yet. Here in a couple hours it may be a moot point. Had a little snag with the meter board but Joe at White Oak Audio cleared up the snag. Onward.

 

[laatsch55]

Re: Larry's 700B

Got the meter board wired in, mI'll be load testing and setting bias for the last time in a few minutes.

 

[laatsch55]

Re: Larry's 700B

The load test is over. Test conditions; Leader LBO-308S scope, Eico 377 signal generator, Fluke 179DMM, 2-400 watt 8 ohm loads. It's a beast.
Using --Power(watts)=volts squared/ ohms gives us 492 watts at 200 hz, 502watts at 2000Hz, 316 watts at 20,000hz.
All measurments were with both channels driven.

 

[laatsch55]

Re: Larry's 700B

Now the fun part. 15 minutes and the listen test will begin. I expect this to take most of the night.

 

[laatsch55]

Re: Larry's 700B

You know what I'm doin!!!

OK, imagine this, A KICKASS SPEC 2 with more headroom. Yep, that's what we got here.
Took the fuses out on the horns twice (not the bass bins) till i set the attenuators on the crossovers, it appears the 700 is a little brighter in the midrange, other than that A louder Spec 2 is what we have. Didn't think that was possible. I have not generated this SPL from a single amp setup, till now. I also didn't know the KHorn bass bin could get louder, it did.

Larry, I think you'll like it, and depending on your neighbors taste in music they might too.

PS, the heavy bass passage on "Star Shpongled Banner" took out my 2 300 watt incandescent bulbs I use in the mancave.

 

[laatsch55]

Re: Larry's 700B

The aftermath........

 

[Elite-ist]

Re: Larry's 700B

Hi Lee,

That is serious power from the 700B! Do you have a 20 amp breaker for the circuit in that room? I know, the light dims, momentarily, in my bedroom when I power up my Pioneer Elite M-90. To your knowledge, is there anyone else who has done the modifications you have done so far, or achieved the kind of numbers you generated at full load(s) on another Phase linear 700B? That's better than the factory rating. Good job, Lee. How do you feel about giving it back to Larry?

Nando.

 

[laatsch55]

Re: Larry's 700B

Ya know Nando what 've done should have not increased the power, raising the rail voltage is the only thing that should have done that. Advertised is 345 at .01 THD, IIRC, 425 just before it clips, I can not explain the 500 watts. I'm sure this has been done hundreds of times to these 700 B's, like I said before Nando, I wouldn't make a pimple on a real tech's ass, but I'm a fast learner and I retain well. A REAL TECH COULD EXPLAIN THE ANOMOLOUS READINGS. Hell could have been my test gear but somehow I doubt it. When Larry takes this to the Capital fest maybe some one there could stress it and see what they get. I don't possess a distortion analyzer although thats on the agenda.
I restored a 700 Ser I and had readings above the 425, IIRC they were 457. It will be interesting to see how the Cali 700B's turn out, then I'll have some baseline info.
I feel like a mother giving up her child, well a foster mother anyway.
I have 2-30 amp dedicated circuits feeding the rack, wired with #10 THHN solid.
I know for a fact I had not heard " Star Shpongled Banner" that loud.
It's also my understanding that a scope is Peak-to-peak voltage, RMS would be P-to-P times .707, so that doesn't jive with the voltage on the Fluke DMM WHICH IS RMS. Perhaps a scope calibration is in order.

 

[Elite-ist]

Re: Larry's 700B

Lee: As good as the test instruments at your work station are, you, also, have two mounted on the side of your head. You, already, know what your modded Pioneer Spec is capable of, and the PL 700B is now to be rebadged as a PL 1000B. Did the resonance on the low notes, while playing SSB, pop those light bulbs like a pair of cherry bombs?

Looks like the aftermath at your shop was the result of a few long nights. Where's the empties, or do you recycle those beer cans as quickly as you down them?

Nando.

 

[laatsch55]

Re: Larry's 700B

Yep, the two test instruments on the side of the head tell me it was way louder than the Spec, and yes the bulbs gave up their filaments in a flash. Actually it was a bunch of Crown and Cokes, you Canadiens make good whiskey. When i was younger and broker i used to drink Canadian Hunter. We called it poor mans Crown.
I do not praise the PL lightly, it takes a lot for me to say it bests the Spec, some long held beliefs have been challenged. Not that I'll ever give up the Spec's. It's just that i have a pair of 700B's to go with my pair of Spec 2's. Life is good.

 

[Elite-ist]

Re: Larry's 700B

Lee: Canadians take pride on making good booze to live by. It's remarkable how powerful that amp is, as (and I don't need to tell you) it takes twice the power output to achieve just a 3dB increase in SPL.

So, the mods you have used on Larry's amp will be used to make another UFC 700B?

Nando.

 

[speakerman1]

Re: Larry's 700B

I may have to go to my cousins farm to test it. I was scared before now I'm really scared. Did you get it to clip? I'm sure the Norman Labs aren't rated @ 500 watts. Did it ever distort? You have to put your mark some where on it to say you were there. Now you have given me incentive to work on the Labs. Am I going to cry like a baby when I crank it? The little Chinese lady will call the cops. LMAO To bad I'm 100 feet in the city limits. In my sound room I hit 3 and I'm @ 100dbs before this. I know the Black Gates didn't change the wattage; but what about sound?

I don't know how to thank you. Mark said he is getting ready to send the Onix CDPs to me. I was going to pull the CBs out of the Labs now I don't know. LOL Do you want my 1st born? He is a pain in my butt. LOL. I might go get you some Virginia Gentleman. If you like Crown you will throw it away after you taste what Virginia can do with whiskey. I'm glad I don't drink any more or I would probably burn the house down. Maybe I'll start doing parties. LOL

Larry

 

[Web Police]

Re: Larry's 700B

Looks good. Your gonna like it Larry.

 

[laatsch55]

Re: Larry's 700B

Never even got close to clipping it, and my ears could detect no distortion in the 400-450 range.
Keep the CB's in the normans, they've saved a set of CV D-9's of mine quite a few times.
Yeah Web, it's good stuff.

The sound..................Ya have to hear it Larry. If you love music like I do, it should bring a tear to your eye.

AND i'M ALWAYS UP FOR TASTING GOOD WHISKEY. Ive been told I'm a jolly drunk, not a mean one.

Nando, I'll stay as close as I can to the same procedure as this one, minus the mistakes of course.

 

[laatsch55]

Re: Larry's 700B

News Flash!!
Joe at White Oak Audio is prototyping some new replacement PL14A/B boards, both stock and an enhanced version. That's fantastic news for us PL nuts, looks like the future is pretty bright for quality, affordable high wattage. I gotta get him to include the DC protect though. I think that would be something a fella could not refuse. If you've seen any of his stuff it's top quality, and like us he's a vintage dude. We'll keep you posted on this.
He oroiginally was talking about a fully comp version too.................................