White Oak Audio Design - Model ONE 1000 Watt Stereo Amplifier

mlucitt

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Yeah, So I blew the rail fuses on the first trip to the Power / Load test...
Joe told me I was "clearly" into the SOA Range...

Testing continues, but I did record a Residual Noise value of 99.3uV at Minimum Volume and 442.9uV at Maximum Volume.
The THD+N on Channel A was .0064% and .0037% on Channel B. Don't know why the slight difference, maybe I was standing on the Channel A side?
 

Mohawk

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I figured that would be the case !

Did you ever publish a Mod to change the 400 / 700 thermal switches to DC ?
Any particular scheme that would be beneficial ?

- Take the + or - DC from the rectifier and run series through the thermal switch or would that be asking for fantom trips via voltage drops ?

I think we may have touched on this but I can't remember .....
 

Gepetto

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I figured that would be the case !

Did you ever publish a Mod to change the 400 / 700 thermal switches to DC ?
Any particular scheme that would be beneficial ?

- Take the + or - DC from the rectifier and run series through the thermal switch or would that be asking for fantom trips via voltage drops ?

I think we may have touched on this but I can't remember .....
I did not touch on this Matt, to do that you need a control board of some form to disconnect the AC in cases like that. The Model ONE has a full blown power control board in it to handle this task and others. I have thought about that however for the existing PL amps, just not published anything on it (until now).

If you have installed the DC protect from Don Imlay, you could potentially get some benefit by running the rectified secondary AC run that powers that DC protect board in series with the one (PL400) or two (PL700) thermal switches instead of the AC primary runs present today. That would leave the amp powered in a thermal overtemp state but would disconnect the load allowing the output stages to cool down with no load attached. Don would have to comment on this but it potentially has some merit.

Also that run would not be pure DC, it would be the half cycle rectified AC for that run.
 

grapplesaw

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Just thought while your talking overheat switch wiring

I’m using a low voltage dc switch with the heat switch in series with it to operate a soft start I’m putting in
No ac along the run
 
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mlucitt

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THD & N ?? Any filters? 30k Out, 80 K out??
Still learning the AP Portable One Plus... I was running 1kHz, figured it was the most appropriate/comparable.
I wish there was a class/school for the various operations of the AP machine. I would sign up in a heartbeat.
Maybe I should just book a flight and spend some time in the Laatsch Mancave.
In the Summer!
 

laatsch55

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Still learning the AP Portable One Plus... I was running 1kHz, figured it was the most appropriate/comparable.
I wish there was a class/school for the various operations of the AP machine. I would sign up in a heartbeat.
Maybe I should just book a flight and spend some time in the Laatsch Mancave.
In the Summer!
There are worse places to be...
 

mlucitt

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The WOA-1000 is in the System!
I must say, the audio is brighter than my Full WOPL'd PL700B. I did not think it would be that different. WAIT, I thought maybe it was just listening bias, so I put the PL700B back into the System with my Carver C-19 CD Player. It was a bit duller, so the WOA-1000 went back into the System and paying some Live Van Halen (a CD I borrowed from my friend Jason Irvin back in 1978), it did indeed sound brighter, not harsh; just clearer and with more brilliance in the mid-range - vocals were more pronounced. I think the two units look good together...
Maybe some Black knobs?

Full Power runs (at Mach 10) coming soon.
15 In System.jpg
 

Gepetto

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The WOA-1000 is in the System!
I must say, the audio is brighter than my Full WOPL'd PL700B. I did not think it would be that different. WAIT, I thought maybe it was just listening bias, so I put the PL700B back into the System with my Carver C-19 CD Player. It was a bit duller, so the WOA-1000 went back into the System and paying some Live Van Halen (a CD I borrowed from my friend Jason Irvin back in 1978), it did indeed sound brighter, not harsh; just clearer and with more brilliance in the mid-range - vocals were more pronounced. I think the two units look good together...
Maybe some Black knobs?

Full Power runs (at Mach 10) coming soon.
View attachment 79862
Mark your setting looks better than mine which is sitting on a red lab cart :)
 

Vintage 700b

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The WOA-1000 is in the System!
I must say, the audio is brighter than my Full WOPL'd PL700B. I did not think it would be that different. WAIT, I thought maybe it was just listening bias, so I put the PL700B back into the System with my Carver C-19 CD Player. It was a bit duller, so the WOA-1000 went back into the System and paying some Live Van Halen (a CD I borrowed from my friend Jason Irvin back in 1978), it did indeed sound brighter, not harsh; just clearer and with more brilliance in the mid-range - vocals were more pronounced. I think the two units look good together...
Maybe some Black knobs?

Full Power runs (at Mach 10) coming soon.
View attachment 79862
Congratulations Mark!
Thanks for taking us along on the build, and sharing your thoughts on audio impressions.
That Model One is a beautiful amplifier.....inside and out .......in a league of it's own !
 
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