Kevin's "I Want a Phase Linear 700 B White Oaked" thread

[laatsch55]

AC mains conditions

 

[Gepetto]

Crosstalk looks accurate Lee...would like to investigate that a bit more and find out the contributors. Some of it may be the "totally" shared power stage for the front end in the PL20 board.

 

[laatsch55]

Ok whatcha want??

 

[Gepetto]

the 3% is from the capacitor input front end on the 700 and your house wiring impedance.

 

[laatsch55]

SEriously??? How does it know what it is off the caps????//

 

[laatsch55]

Oh, that's what causes the distortion??

 

[laatsch55]

Ok , doing a little reading here. Since we are quantifying the White Oak upgrade from the stock config, It says here I can do an in and out gain from the ratio screen. I'm thinkin that might be useful.

 

[Gepetto]

Yup Lee, that is what causes the distortion on the AC mains that you measure. The peak charging of the bulk caps distorts the AC line when that huge current spike occurs. That is why switching power supplies have included Power Factor Correctors (PFC) front ends to make the power supply look resistive to the line. New international regulations are requiring that in new equipment. PFC equipped equipment would not produce that AC line distortion.

 

[Gepetto]

That probably would be useful Lee. To see that compare.

Signing off, done for the nite.

 

[laatsch55]

Later, me too . Sleepin at the console.

 

[laatsch55]

dB gain in and out.

 

[laatsch55]

Output level in watts into 8 ohms, both driven , then left only and right only. Just before clipping on all. This puppy is sick. Needs some White Oak TLC.

 

[laatsch55]

Guys, couldn't keep fuses in it long enough to get a screen dump of the 4 ohm output levels. BUT I can say at 1khz both channels loaded and driven it was outputting 54 volts, yep----729 WATTS!!!! It kept blowing the 10 amp main fuse. I'll try it again tomorrow with a 15. Had to go with 10 amps on the rail fuses.

 

[kevin]

WOW !!!! Snuck all this in on me ... I just now say this thread ! Ive been in the garage all day getting the mower ready !!! I'M EXCITED !!!!!!!!!! and not about the mower !

 

[laatsch55]

How do ya "sneak" 4 pages of thread by??

 

[Gibsonian]

So 729 watts, no clipping yet, limiting item was fuses, and with stock board?? Do I have it correct so far Lee?

 

[jbeckva]

PUT A 20 AMP IN THERE.. LET'S SEE SH** BLOW UP!!! BOOM BAM BING BONG KAPOWEEEE!!

(c'mon.. you know you want to.. enabler-me says GO)

* - don't forget to put a big bulletproof shield 'round er...

 

[laatsch55]

So 729 watts, no clipping yet, limiting item was fuses, and with stock board?? Do I have it correct so far Lee?

Correct Scott. Had the input impedance wrong on the AP too. It did scream a wee bit also.
Gotta say, shit got hot in a hurry. I can see why the PL's got a reputation if they pushed 4 ohms with em all the time. Without some air movin at my listening levels they wouldn't stand a chance.

 

[laatsch55]

PUT A 20 AMP IN THERE.. LET'S SEE SH** BLOW UP!!! BOOM BAM BING BONG KAPOWEEEE!!

(c'mon.. you know you want to.. enabler-me says GO)

* - don't forget to put a big bulletproof shield 'round er...

Let's just say I didn't "hover" real close when this was going on.

 

[Gibsonian]

So 729 watts, no clipping yet, limiting item was fuses, and with stock board?? Do I have it correct so far Lee?

Correct Scott. Had the input impedance wrong on the AP too. It did scream a wee bit also.
Gotta say, shit got hot in a hurry. I can see why the PL's got a reputation if they pushed 4 ohms with em all the time. Without some air movin at my listening levels they wouldn't stand a chance.

So you are stopping there or are you going to try to make her clip? Sound like fans need to be moving air when doing this, esp. after you've built her into a PLWO (protect your investment).