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While the APS guys trying to figure out why this unit can not handle power (which more likely involved a phone call to China :-) I decided to give another try across everything, repeating my last listening, this time in relaxed environment with different music and with some sense not obligation to try the unit but rather enjoyment.

I made some observations that I feel worth to share.

1) The more I load to APS the worst it sounds. The buffer on my preamp, DAC and CD transport it almost OK, but if I load juts one of any component then it sound even better. Om the scope the idle APS unit has a near perfect wave and it become to be twisted even if I load 15W. Not good at all! Still up to 100W the sound is till fine, and then become bad becoming bad at 200W. BTW, I was loading the resistive load (!!!) With the Milq it is absolutely unusable as it was yesterday. BTW, Melquiades with it’s input choke filter everywhere is an exemplary load for APS unit – much better and much easer load then any other commercial load that the APS use even have seen out there.

2) I was a wrong in the following post:

http://www.audioasylum.com/forums/psaudio/messages/1/10526.html

I was not wrong about the “White Noise”. I was wrong identifying the reasons for it. Now I know the reasons. The “White Noise” did not go through the PP as I accused and was not because the isolation but was due to the fact that my preamp (for years, since 1999-2000 whet I begin to use P300) never was running form regenerators (I never was able to run any analog front end from PP too much sonic problems). With the APS I was actually able to run preamps from regulator and the “White Noise” is gone. Do not forget that the APS unit is much less decoupled form the mains then P300. So, it was not the UHF from the power line where going through (unless the APS’s output low-pass become handy to deal with the “White Noise”….

3) Sound of the VERY little loaded APS unit is extremely good, good, even up to the point of being tacky. In all audio I have seen the only one thing that did the similar trick – jack up dynamic range without to much touching other things and particularly the harmonics – it was Expressive Technology Transformers. Those few what heard my playback in my room would understand my next statement, my enthusiasm about it and how valuable it is: the APS does not screw up bass. Alleluia!!!

4) I would not that I do detect a very very very very very minor thinness in the upperbass and lover midrange region. I did added 1/3dB in my Fundamentals Channels and I feel it does fine now. I could live without it as well.

5) Apparently these little zigzags (20kHz) on the traces above, the residuals of the D-amps switching, do not affect sound.

6) It was eventually a magnificent solution for preamp. I trued in my room since P300 probably 8 preamps – not of them were agree with P300. The APS swallowed my preamp with such a effectiveness that only that was worth the price of admission. In fact it is VERY funny to test the active Placette. It draws a very little current has large CRC filter and a large for given current capacitors. So, what I disconnect the buffer form the power source it runs perfectly fine for quite a number of 5 seconds before collapsing. So, I have my dedicated feed, APS and P300 sitting right next to each other and I can switch them with no interruption in sound quality. So, sticking the Placette buffer into the dedicated lines (essentially the raw mains) I have the “White Noise”, some compression, and brutal upper range. Sticking the buffer into the P300 it sounds like someone dipped music into motor oil. Sticking the Placette into the APS made me not wiling to make this experiment again. Sing the brass opening of the last movement of the Dvorak’s New Wold…

7) OK, the price of admission. I begin to wonder about it. The unit is very large (running completely cold BTW) and frankly speaking pricy. How about the rest of my digital (AD/DA), how about my 3 phonostage, do I need to buy another APS unit….? Yep, you right! If the APS guys will not be able to detect what is going  on and why it dies with power then I would hardly feel that it worth to have this devise to run juts my fa few itemps of my ront end. From a different perspective I would like do not loose the Sound that I got from the APS. So, perhaps if the 150W is max that is possible to get from APS units then I need to harass these guys with request to come up with MUCH smaller, much less expensive 150W, no stupid buttery backup devise. But once again… who knows: if they would do 300W unit then would it men that it will sound good only at no more then 10% of it load?

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