Amplifiers with IcePower 1200AS2, class D module

maty · « **Reply #160 on:** 4 May 2018, 10:45 pm »

On the part of guilt that corresponds to me, I apologize to all those who have bought it.

I am very sorry.

bavmike · « **Reply #161 on:** 4 May 2018, 11:10 pm »

OMG! What a shocking revelation! How did you not catch this months ago? We have all been fooled. It really doesn’t sound good!

bavmike · « **Reply #162 on:** 4 May 2018, 11:30 pm »

After millions invested over a 10 year period, we now learn it was all wasted. Had they only hired Maty years ago this disaster could have been prevented.

Tyson · « **Reply #163 on:** 4 May 2018, 11:38 pm »

Quote from: maty on 4 May 2018, 10:41 pm

I think everyone should read the thread I opened days ago. The new comments are very instructive.

Phase shift in class D amplifiers. How it affects the sound?

http://www.diyaudio.com/forums/class-d/321578-phase-shift-class-amplifiers-affects-sound.html

For me, measurements are always a necessary condition, which is not enough. The 1200AS2 phase graph is unacceptable if you want a top system I think.

I summarize it: I am glad I did not buy the IcePower 1200AS2.

Ironically, I just bought a 45 SET amp with 2 watts of power and even worse measurements. But I too am glad I didn't buy the IcePower amp

gab · « **Reply #164 on:** 4 May 2018, 11:43 pm »

Quote from: maty on 4 May 2018, 10:45 pm

On the part of guilt that corresponds to me, I apologize to all those who have bought it.

I am very sorry.

Me too Maty. I bought 2. If I had only listened to you. So sad. So sad.

gab

restrav · « **Reply #165 on:** 5 May 2018, 12:10 am »

NELSON pass should hire maty to take care of the necessary stuff for him.

restrav · « **Reply #166 on:** 5 May 2018, 12:10 am »

oh i forgot to bold the word necessary

Ron D · « **Reply #167 on:** 5 May 2018, 12:13 am »

I guess there can be at least 2 camps:

1. People that base their entire decisions on measurements. If it measures like crap it obviously sounds like crap despite what one hears.
2. I don't care what the measurements are, I either like it or I don't telative to how it performs in my set up.

Tyson, one could assume that you are in camp #2 as I am and I would think I don't have the depth of experience you have but if one likes what they like does experience really matter?

If I am wrong as Rosanna Danna once said "never mind"....

WGH · « **Reply #168 on:** 5 May 2018, 12:13 am »

Maty, I tried to warn you but noooooo, you went ahead anyway. I had the same response commenting on the nCore amps, quit while you are still ahead of the crowd.

Tyson · « **Reply #169 on:** 5 May 2018, 12:21 am »

Quote from: Ron D on 5 May 2018, 12:13 am

I guess there can be at least 2 camps:

1. People that base their entire decisions on measurements. If it measures like crap it obviously sounds like crap despite what one hears.
2. I don't care what the measurements are, I either like it or I don't telative to how it performs in my set up.

Tyson, one could assume that you are in camp #2 as I am and I would think I don't have the depth of experience you have but if one likes what they like does experience really matter?

If I am wrong as Rosanna Danna once said "never mind"....

I used to be firmly in camp #1, now I'm in camp #2. I'm a Gen X person so I love technology (and I work in IT), so I always had a bias that newer (and better measuring) is better. But the more I'm in the audio game the more I think we made a wrong turn when high powered SS amps were invented and low efficiency speakers became the norm. And now with Class D it seems like we're just going faster and faster in the wrong direction.

But, I could be wrong. The nCore amps all pretty much sucked, but perhaps the newest generation won't. So I'm open, but skeptical.

JohnR · « **Reply #170 on:** 5 May 2018, 01:52 am »

Um, the graph is of the output impedance vs frequency, with both magnitude and phase shown. It does not show "phase shift" of the audio signal.

(For example, at 10 kHz the output impedance is 0.03 ohms with a phase component of 70 degrees. It's hard to see how this can have any consequence at all.)

gab · « **Reply #171 on:** 5 May 2018, 01:56 am »

Quote from: maty on 4 May 2018, 10:41 pm

I think everyone should read the thread I opened days ago. The new comments are very instructive.

Phase shift in class D amplifiers. How it affects the sound?

http://www.diyaudio.com/forums/class-d/321578-phase-shift-class-amplifiers-affects-sound.html

For me, measurements are always a necessary condition, which is not enough. The 1200AS2 phase graph is unacceptable if you want a top system I think.

I summarize it: I am glad I did not buy the IcePower 1200AS2.

And in thread #31 of your DIYaudio thread above you summarize: "IcePower 1200AS2 is only usable (high end audio) up to f < 500 Hz.[/b] "

I am pretty sure there are LOTS of people with 1200AS2's that will disagree with your finding of < 500 Hz ....

Can we at least agree that the 1200AS2 amp shouldn't be used for high end audio above 700 Hz? Or maybe 800 Hz?

I mean come on Maty.....give a little will ya?

gab

OzarkTom · « **Reply #172 on:** 5 May 2018, 02:33 am »

Darn, no 1200as in my future. My 3 year old DAC Cherry amps must also in the same camp. But wait, maybe those two little red lights on top of the amps are actually tubes. Keeping my fingers crossed.

maty · « **Reply #173 on:** 5 May 2018, 06:54 am »

I do not think any class A or class B, tubes or solid states, do not have flat phase at least at f < 20 kHz, I would very surprise.

I wrote an email to the IcePower more than two weeks ago and they have not answered me. The same happens with PS Audio.

************ **************

@WGH

It is a little puppies multitude/crowd. I live in Catalonia (Spain), where a lot of people hate to others to think differently and physically threaten from October 2017, so... they are puppies.

maty · « **Reply #174 on:** 5 May 2018, 08:59 am »

With modern commercial music with so many awful things that they do in the studies, with electronical/computer instruments one more crap will not be noticed I think.

With some speakers it may not be as problematic as with others. But I want a clean poweramp, without harmonics (added via preamp -even harmonics only- if I want) and that does not alter the audio signal.

I do not want to add a new variable to a system that is already complex. I want to remove it from the equation.

JohnR · « **Reply #175 on:** 5 May 2018, 09:35 am »

You're barking up the wrong tree. The graph is not the phase of the amplifier....

Audiogeek2 · « **Reply #176 on:** 5 May 2018, 09:53 am »

Quote from: JohnR on 5 May 2018, 09:35 am

You're barking up the wrong tree. The graph is not the phase of the amplifier....

John, not sure where in Sydney you are located, but if you want to hear/borrow a 1200AS amp let me know. So far everyone locally who has heard it in a few different systems have been very positive.

maty · « **Reply #177 on:** 5 May 2018, 10:48 am »

Which is the usual graph of the output phase in a well-designed class-D amplifier?

OzarkTom · « **Reply #178 on:** 5 May 2018, 01:11 pm »

As long as the system gives me the emotion I want, I don't care what the measurements say or class tube, a,b,c,d, or z.

glynnw · « **Reply #179 on:** 5 May 2018, 02:51 pm »

I have a Mivera amp with the new ICE board and I love it guys. I am in the "measurements be damned' camp and this new amp sounds better to me than either of my 2 tube amps. After 2 weeks I keep looking for a fault and have not yet found it. In the past 3 days I have twice switched to a tube amp to compare and quickly went back to the ICE amp just because I preferred the sound. I have owned several class D amps in the past and they were too harsh in general - not so now.