[maty]

My words about PS Stellar M700

Re: Are we on the verge of a SS revolution???

http://www.audiocircle.com/index.php?topic=156250.msg1673278#msg1673278

Good class D IcePower 700ASC module with a buffer (PS Gain Cell) -> H3 predominance. I find it an incomprehensible decision.

[OzarkTom]

But you can get the M700's and their gain cell DAC for $3999 also. Max trade in is $1200.

https://www.psaudio.com/products/stellar-m700-gcd-combo/?utm_source=facebook&utm_medium=dearlocal&utm_campaign=stellar_package_dearlocal

PS Audio also accepts Amazon and Paypal credit cards. Free shipping and 30 day trial.

[Mark V.]

But you can get the M700's and their gain cell DAC for $3999 also. Max trade in is $1200.

https://www.psaudio.com/products/stellar-m700-gcd-combo/?utm_source=facebook&utm_medium=dearlocal&utm_campaign=stellar_package_dearlocal

PS Audio also accepts Amazon and Paypal credit cards. Free shipping and 30 day trial.

I would be a bit careful with this amp and not buy it "blind". There was a pair of them available 2nd hand in our country for EUR 2300 (EUR 3500 new). It seemed this pair of amps was already owned by 2 different people. So if they are that good as what some people do say, why do they change owner that often?

[OzarkTom]

I would be a bit careful with this amp and not buy it "blind". There was a pair of them available 2nd hand in our country for EUR 2300 (EUR 3500 new). It seemed this pair of amps was already owned by 2 different people. So if they are that good as what some people do say, why do they change owner that often?

30 day trial from PS. Not so good if you live out of the states. No amp is perfect.

[Roninaudio]

I would be a bit careful with this amp and not buy it "blind". There was a pair of them available 2nd hand in our country for EUR 2300 (EUR 3500 new). It seemed this pair of amps was already owned by 2 different people. So if they are that good as what some people do say, why do they change owner that often?

Hard to judge an amps performance by just one example.. You see them for sale infrequently here to but for many different reasons. I have never heard sound or quality as a factor for sale; people flip equipment for various reasons.  As mentioned above no amp is perfect and some systems have synergy with other components and some system matches leave a bit to be desired.  I have them and love them. They fit in my system very well. Also the reviews are top notch.  However as in your example above, one review does not tell the whole tale either.  In home listening is always best..

"Set up side by side rather than stacked, and sitting on IsoAcoustics Orea Audio Equipment Isolators, the Stellar M700s came ever so close to matching the sound of my high-end reference monoblocks, Theta Digital's Prometheuses—which are ranked Class A in "Recommended Components" and, at $12,000/pair, cost four times as much as the PS Audios. The Stellar M700 is an outstanding bargain."


https://www.stereophile.com/content/ps-audio-stellar-m700-monoblock-power-amplifier

[maty]

First post updated with:

Purepower Icepower 1200AS2 amp listening impressions

https://www.miveraaudio.com/forum/purepower-amplifier/purepower-icepower-1200as2-amp-listening-impressions

[maty]

Mike

Another review of the Mivera Audio Purepower SE. However this guy is so against believing cables, connectors and case quality makes a difference in sound that he refuses to mention the amp he heard or who actually made it.

https://forum.audiogon.com/discussions/the-new-ice-edge-1200as2-amp-module

I agree with Mike (Mivera Audio). In a review you must say the manufacturer or assembler of the class D module if it is not diy.

And the preamp + speakers (sensitivity at least) too.

[wushuliu]

I agree with Mike (Mivera Audio). In a review you must say the manufacturer or assembler of the class D module if it is not diy.

Wha?

Anyway, that review makes the amp sound an awful lot like the TPA32XX amps I have, just with more power. So far I am not sensing the same level of GAME CHANGER status from the 1200AS2 as when Ncores hit the scene.

[maty]

He does not build the amplifier like a diyer.

The case and cables geometry/build is more important with class D technology. I have verified that I need at least 4 mm aluminum (better more) or 1 mm steel sheet to avoid the very great RF/EMI I have in my house. With two class AB amplifiers and with my cheap USB DAC (ODAC).

With 1200AS2 you do not need to add a good buffer (with very low SNR) and PSU. More cheap!

[maty]

http://www.ti.com/product/TPA3251

[PDF] http://www.ti.com/lit/ds/symlink/tpa3251.pdf

http://www.ti.com/product/TPA3255

[PDF] http://www.ti.com/lit/ds/symlink/tpa3255.pdf

I suspect that the SNR (about 112dB) is at max power. Much less than IcePower 1200AS2 or Hypex NC500 v2 at the same power.

tpa3251.pdf, page 8

SNR is calculated relative to 1% THD+N output level

* BTL: 111 dB

* SE: 100 dB

And the true power at THD 0.1% is much less!!!

TPA3251 vs. TPA3255 THD according to datasheet

http://www.360customs.de/en/2016/09/tpa3251-vs-tpa3255-thd-nach-datenblatt/

[IMG] http://www.360customs.de/wp-content/uploads/2016/09/g5078-5.png


And one thing are the chip specs and other their implementation in a board like DAC.

[maty]

IcePower 100AS1 / AS2 have the TPA3251.

https://icepower.dk/products/amplifier-power-modules/as-series/

ICEpower 100AS2

Containing a capable fly back power supply with a continuous power capability of 100 W and a short-term power of 300 W, combined with a 2x 100 W class D amplifier. The 100AS2 is perfect for applications such as stereo hifi and home automation amplifiers, active speakers, studio monitors as well as 2 channel guitar or bass amplifiers without the need for forced cooling.

[PDF] https://icepower.dk/download/2431/

Key Specifications

 1 x 100 W/4 Ω (100AS1) and 2 x 100 W/4  (100AS2) @ 1 % THD+N, 1 kHz
 0.003 % THD+N @ 1 kHz, 10 W/4
 50 kHz audio bandwidth
 <77 uV A-weighted output noise [maty: at max power, 100 W/4  (100AS2) @ 1 % THD+N]
 Minimum load impedance at 3 Ω
 Output currents up to 12 A
 +8 V DC and +/-17 V DC auxiliary supply outputs
 Universal mains (100 – 240 V, 50 – 60 Hz)
 Size (LxWxH): 140 mm x 77 mm x 36.5 mm (5.51 inch x 3.03 inch x 1.44 inch)

Chip specs: 60 μV (A-Weighted) Output Noise

[OzarkTom]

So Maty, how many of these Icepower amps do you own or have heard?  Most people here never rave about something they have never heard before in their system.

[rklein]

Wha?

Anyway, that review makes the amp sound an awful lot like the TPA32XX amps I have, just with more power. So far I am not sensing the same level of GAME CHANGER status from the 1200AS2 as when Ncores hit the scene.

I had diy'd tricked out NCore monos which were very good.  Since then, I unfortunately have gone down the rabbit hole when it comes to amps.  Modwright, Odyssey Kismets, Wells Audio...finally found Nord and Colin built me some very nice One-Up monos based on the NC500 modules.

I must say that the 1200AS2 modules are the best amps that I have had in my system.  I bought an SE version from Mike at Mivera and could not be happier.  IF the 1200AS2 is like TPA32XX amps that you have then the TPA32XX must be very good indeed.

Regards,

Randy

[OzarkTom]

I believe you Randy, I just wonder why a certain person here that downplays every other amp design except one. Does he really own one? Or is he just a salesman for a certain company here?

Anyway all  1200as companies are using the exact same module. Would a DIY'er buy a 1200as module and install it in a broken Krell or Classe amp chassis and have the very best sound of all? That should cost about 2000 or less.

[fredgarvin]

I had diy'd tricked out NCore monos which were very good.  Since then, I unfortunately have gone down the rabbit hole when it comes to amps.  Modwright, Odyssey Kismets, Wells Audio...finally found Nord and Colin built me some very nice One-Up monos based on the NC500 modules.

I must say that the 1200AS2 modules are the best amps that I have had in my system.  I bought an SE version from Mike at Mivera and could not be happier.  IF the 1200AS2 is like TPA32XX amps that you have then the TPA32XX must be very good indeed.

Regards,

Randy

Hi Randy, could you share what preamp or dac is feeding the Mivera, and speakers? 

[poseidonsvoice]

Hi Randy, could you share what preamp or dac is feeding the Mivera, and speakers?

Here:

https://www.audiocircle.com/index.php?topic=156814.msg1681136#msg1681136

Best,
Anand.

[maty]

@OzarkTom

I always write about specs in this thread.

If you have a class D module with very good specs you will want a buffer with specifications as similar as possible. The same with the PSU.

I was about to buy the initial kit, which I thought I would improve by spending the least. But I decided to try to improve even more the cleanliness of my disastrous mains. The improvement was so substantial that I decided that it was not worth risking to ruin a system that caused adrenaline rushes with some excellent recordings of analog master that I have, many of them probably recorded with tube equipment -> H2 predominance is my hypothesis -> EMOTION.


Re: How to clean the DC at mains. And ripple too.

https://www.audiocircle.com/index.php?topic=153802.msg1667589#msg1667589 EMOTION

https://www.audiocircle.com/index.php?topic=153802.msg1672876#msg1672876 GLORIOUS

https://www.audiocircle.com/index.php?topic=153802.msg1673121#msg1673121 Beauty

https://www.audiocircle.com/index.php?topic=153802.msg1675899#msg1675899 Awesome

https://www.audiocircle.com/index.php?topic=153802.msg1675913#msg1675913 EMOTION

https://www.audiocircle.com/index.php?topic=153802.msg1677229#msg1677229 More addictive

After the incredible improvement the logical thing is to enjoy music that gets excited and not take risks with a very different technology like class D.

I am not a compulsive buyer. For me the most important thing is music, enjoy and get excited when listening to it.

[mresseguie]

I always write about specs in this thread.

If you have a class D module with very good specs you will want a buffer with specifications as similar as possible. The same with the PSU.

I was about to buy the initial kit, which I thought I would improve by spending the least. But I decided to try to improve even more the cleanliness of my disastrous mains. The improvement was so substantial that I decided that it was not worth risking to ruin a system that caused adrenaline rushes with some excellent recordings of analog master that I have, many of them probably recorded with tube equipment -> H2 predominance is my hypothesis -> EMOTION.


Re: How to clean the DC at mains. And ripple too.

https://www.audiocircle.com/index.php?topic=153802.msg1667589#msg1667589  EMOTION

https://www.audiocircle.com/index.php?topic=153802.msg1672876#msg1672876  GLORIOUS

https://www.audiocircle.com/index.php?topic=153802.msg1673121#msg1673121 Beauty

https://www.audiocircle.com/index.php?topic=153802.msg1675899#msg1675899 Awesome

https://www.audiocircle.com/index.php?topic=153802.msg1675913#msg1675913 EMOTION

https://www.audiocircle.com/index.php?topic=153802.msg1677229#msg1677229 More addictive

After the incredible improvement the logical thing is to enjoy music that gets excited and not take risks with a very different technology like class D.

I am not a compulsive buyer. For me the most important thing is music, enjoy and get excited when listening to it.

Keep doing what you're doing, Maty. You're fine in my opinion.

Enjoy life!

Michael

[fredgarvin]

Here:

https://www.audiocircle.com/index.php?topic=156814.msg1681136#msg1681136

Best,
Anand.

Thanks Anand.

[maty]

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.