Johan's Phase Linear 700B Fully Comp Conversion

[laatsch55]

Yes I did Johan, thanks.

 

[Skynyrd77]

Throw out the dynamic output rating, it means nothing. Amp section distortion specs are GOOD. Power appears to be 150 watts into 8 before clipping.. The 4 ohm and 2 ohm rating show the power supply is not up to the task of doubling power into 4 ohms and then doubling again into 2 ohms, WHICH is what a properly desighed power supply should provide to the amp section. A lot of factors come into play when you see a rolloff of power into the lower ohm loads. Output devices having a limited current rating, transformer compromises, caps, etc.
A commercial application of any audio desigh is going to be a series of compromises, in essence it has to be to be a commercial success. Therein lies the niche for folks like Joe and his "take no prisoners " approach to his kits.He specs the very best components that he can reliably get, withthe result being what most of you have heard....exceptional sound quality. It does take a lot of effort on the implementation side to make it happen, but the cost savings are worth the effort and it's been shown time and again with the upfront engineering of Joe's, and some situationasl, and personal supervision it can be done by a wide spectrum of folks with varying degrees of expertise.


Sorry for not answering more of your question Jase, tuners and pre sections are still pretty foreign to me, but felt qualified to comment on the amp section...

Thsnks lee! As soon as I typed this morn the 12 hour flu hit me. It was the worst flu I've had !!!! 2hoots later I'm starting to come to life again!!!

 

[laatsch55]

Welcome Sir...

 

[laatsch55]

One last test suite before goes, all buttoned up...

 

[Gepetto]

One last test suite before goes, all buttoned up...

That is one pretty amp Lee...

 

[laatsch55]

Yeah, sounds even prettier...

Hookay......We have a new low-noise champeen in the house!! These are UNWEIGHTED figures. *8 ohm load, inputs terminated internally to the AP with 39K resistance.... Jeez people, these are low noise EVEN FOR A 400!!!!

 

[laatsch55]

IEC "A" weighted----

 

[laatsch55]

Other measurements.... SNR at rated output of 350 watts RMS into 8 both loaded and driven...

 

[laatsch55]

Frequency Response...

 

[laatsch55]

THD & N right and left--Tables....8 ohm load, 15 watts output, bias 387 left, 385 right.

Disclaimer---These figures show exactly three times what Joe has tested his at. My confidence is not real high on the AP distortion figures right now. Joe is showing .24% at 20Khz and goes down exponetially from there down to 20Hz. The FC amps are showing more distortion than the quasi amps but sound cleaner.....go figure...

Both tables are stated as "Right" channel, but one was mislabeled...

 

[laatsch55]

One more listen. Jani will make up the performance book in the morning then off it goes. The top is off to set bias one final time...

 

[derek92994]

Nice, what were the final specs?

 

[johan1212]

.....I wish all these figures would mean smtg to me....but if Joe and Lee are both excited about them,can only be good...lol...thanks guys..

 

[johan1212]

.....distorsion figures is smtg I know about....and you r right Lee....they are high....weird......and your listening of music was good?...keeping my fingers crossed....lol..if needed ,keep it more days if you think its or not normal or not good enough...you r the expert...not me...let me know..
thanks

 

[johan1212]

lee....is unit running warmer then before?..

 

[laatsch55]

D2, these are the final specs, just posted before your post.

Johan, I don't hear that distortion...that's why I say I'm not to confident in the figures. I'm gonna send it, and if you're not happy with it send it right back. Keep the cabbage case for a couple days while you evaluate it..

 

[laatsch55]

lee....is unit running warmer then before?..

Yes Johan I think they run a little warmer than the stock units..

 

[Northwinds]

THD & N right and left--Tables....8 ohm load, 15 watts output, bias 387 left, 385 right.

Disclaimer---These figures show exactly three times what Joe has tested his at. My confidence is not real high on the AP distortion figures right now. Joe is showing .24% at 20Khz and goes down exponetially from there down to 20Hz. The FC amps are showing more distortion than the quasi amps but sound cleaner.....go figure...

Both tables are stated as "Right" channel, but one was mislabeled...

This could actually be a good thing. People blah blah blah about how great their tube amps sound and what they are hearing is distortion when they put the gas to them but say it's so warm and comfy LOL

 

[johan1212]

D2, these are the final specs, just posted before your post.

Johan, I don't hear that distortion...that's why I say I'm not to confident in the figures. I'm gonna send it, and if you're not happy with it send it right back. Keep the cabbage case for a couple days while you evaluate it..

good idea....make sure you send it to my office adress....as usual..
thx

 

[laatsch55]

This could actually be a good thing. People blah blah blah about how great their tube amps sound and what they are hearing is distortion when they put the gas to them but say it's so warm and comfy LOL

Tube amps distort in even order harmonics, SS amps in odd order harmonics, very different set of circumstances
. Evens are pleasing to the ear, odds are not. This amp doesn't sound like those figures represent, therefore the disclaimer.

I've got another one to do right quick this week so we'll see...