Good Class D amps ??

[crenca]

3 minutes ago, GeneZ said:

 

 

That's how I came across?    I was speaking of speakers rated at 2 Ohms. (which is how the premise was worded).  Not speakers that simply dip into 2 Ohms.  Meaning,  some speakers dip near to zero ohms.

 

Like here!  https://www.audiocircle.com/index.php?topic=18325.0

 

Not disagreeing with you on the back and forth, but the end user (consumer) of speakers is better served by looking at the "dip" as opposed to the rating.  Since there is a rating game going on, the rating is as often as not not informative.  So the "dip" becomes a more useful data point.  Often, the "dip" is down around in the mid bass where there is alot of musical energy (particularly in modern genres) and so the consumer should be interested how the amp/speaker are going to perform there...

[Matias]

14 minutes ago, GeneZ said:

 

 

Definitive Audio Pro Monitor 800's?      Not to be done.

 

  ? Great little speakers for desktop if you have means for bass reinforcement. 

 

They are tiny and only have three legs built in. Too small for Iso Acoustics  (which I have)...............................

 

 ISO Pucks should do, 3 pairs: https://www.amazon.com/IsoAcoustics-Iso-Puck-Isolation-Studio-Monitors/dp/B06ZZ72LL6

[GeneZ]

1 hour ago, Matias said:

 

 ISO Pucks should do, 3 pairs: https://www.amazon.com/IsoAcoustics-Iso-Puck-Isolation-Studio-Monitors/dp/B06ZZ72LL6

   Thanks.   Good to know. Those pucks were no being sold when I had the speakers.  I really liked them in my set up at that time.  Just vibrated the desk like crazy... 

[GeneZ]

2 hours ago, crenca said:

 

Not disagreeing with you on the back and forth, but the end user (consumer) of speakers is better served by looking at the "dip" as opposed to the rating.  Since there is a rating game going on, the rating is as often as not not informative.  So the "dip" becomes a more useful data point.  Often, the "dip" is down around in the mid bass where there is alot of musical energy (particularly in modern genres) and so the consumer should be interested how the amp/speaker are going to perform there...

Now we know that... and many still do not.   They see the ohm rating listed in the specs and that will be their frame of reference. When someone says they have a two ohm speaker?  I assume there will be a dip and cause many amps problems.  No problem...

[Ralf11]

Can we please discuss Class D amps here?

 

Some of the speaker comments are interesting but belong in a separate thread - and this is notice to re-post them there before they are zapped form here...

 

Thx

[fas42]

Perhaps you might like to start a separate thread on this? Strongly stabilising the speakers has always been an essential part of my 'method', and the better one does it, the better the end results.

[GeneZ]

1 hour ago, fas42 said:

Perhaps you might like to start a separate thread on this? Strongly stabilising the speakers has always been an essential part of my 'method', and the better one does it, the better the end results.

 

Fas 42....   Start the tread and give us a heads up.

..   

Sorry for the hassle Ral11.. 

[fas42]

Busy life stuff at moment - will kick it off in the headphones and speakers forum later today ...

[Matias]

I would really like to see NuPrime's measurements like the typical THD x power graphs by frequency, as ICEpower and hypex use. I could not find any measurements on their website or manuals... Not that I am an objectivist only but still I enjoy analyzing the differences. Specially with all the hype around the Evolution One.

[John769]

On 12/3/2018 at 2:55 PM, Matias said:

 

And I ended up ordering yesterday the Apollon NC800 SL with Sparkos opamp, but I am going to test the SI from a friend as well.

 

On 12/3/2018 at 3:26 PM, mocenigo said:

 

I think none of you two will be disappointed. These amps are just great. Everybody knows where my preference lies and I won't repeat it (I also sent them back for an upgrade and I will report).

 

Looking forward to some more discussion. 

 

"The NCore MP modules have an on board PSU and twin channels providing 85-90% of the sound quality of the NC500 in a compact footprint. They easily outperform older UcD amplifiers. They retain all the bass control, dynamics and most of sound stage and resolution of our NC500 amplifiers out performing most commercial amplifiers found on the high street costing 3-4 times more."

 

Anyone listened to the MP variants?  They seem good value..

[Matias]

@John769 I went the opposite direction, ordering the more expensive PRO opamps to get even higher performance and higher price. But I agree, the NC502MP based stereo power amplifier has a great price.

 

Prices from Apollon website:

- NC800SL (NC500 based - 2 x 400W at 8 ohms) with standard SI opamp - 1575 euros.

- NC800SL (NC500 based - 2 x 400W at 8 ohms) with PRO opamps - 1875 euros.

- NCMP700 (NC502MP based - 2 x 350W at 8 ohms) - 825 euros.

 

Plus optionals.

 

That is half the price for the 502MP. Never listened to them though...

 

 

[esldude]

On 12/22/2018 at 7:34 AM, Matias said:

I would really like to see NuPrime's measurements like the typical THD x power graphs by frequency, as ICEpower and hypex use. I could not find any measurements on their website or manuals... Not that I am an objectivist only but still I enjoy analyzing the differences. Specially with all the hype around the Evolution One.

https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-nuforce-sta-200-power-amp.5039/

 

Measured results for a Nuprime amp.

[Matias]

18 minutes ago, esldude said:

https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-nuforce-sta-200-power-amp.5039/

 

Measured results for a Nuprime amp.

 

Thanks. I was thinking more of the ST-10 and Evolution One amps. But Amir seems to have more entry level DACs and amps available to test in general. Maybe it is what people borrow him so he has not much of a choice in this.

 

Also the datasheets of both ICEpower and Hypex show power x THD for 3 frequencies: 100Hz, 1kHz and 10kHz. And usually the 10kHz one is differente from the others, so it is quite interesting to see how each module handles the frequencies differently. And Amir only measures 1kHz. Still I enjoy reading his measurements.

[Matias]

Actually 6.67kHz instead of 10kHz, no Edit button...

[GeneZ]

On 12/22/2018 at 8:34 AM, Matias said:

I would really like to see NuPrime's measurements like the typical THD x power graphs by frequency, as ICEpower and hypex use. I could not find any measurements on their website or manuals... Not that I am an objectivist only but still I enjoy analyzing the differences. Specially with all the hype around the Evolution One.

 

 

You are going to decide on measurements?  Who has bad measurements today?

[Matias]

@GeneZ ICEpower ASP has quite a bit of THD in 6.67kHz compared to the newer ASX2 and AS, or the nCores. And they are still being sold today (Rotel RB-1091 and W4S SX1000R for example).

 

I decide on both measurements and listening. Just bought my Apollon NC800SL PRO a few weeks ago.

[esldude]

The new Icepower also works at a higher switching frequency. Over 400 khz vs 110 khz. Means reduced interaction between speaker load and treble response from the output filtering.

[GeneZ]

2 hours ago, Matias said:

@GeneZ ICEpower ASP has quite a bit of THD in 6.67kHz compared to the newer ASX2 and AS, or the nCores. And they are still being sold today (Rotel RB-1091 and W4S SX1000R for example).

 

I decide on both measurements and listening. Just bought my Apollon NC800SL PRO a few weeks ago.

  Nuprime does not use off the shelf modules like most other companies utilize. They design and manufacture their own.  I have not heard all.  But, I have heard one company using an ICE module. If I heard nothing else I would simply say it sounded very good, and better than any AB amp I have heard in my system. But, having a Nuprime ST-10 made a nicer difference.   Considering its also been (factory approved) modded by TDSS which makes it quieter yet... I am not sure what folks here are looking for.

 

One thing I believe is true.  If one has to nit pic on what I call ultra measurements?  We really do not know what they are looking for.  In a sense? ..  None of us do until after the purchase. Of course, we all want to make an intelligent decision.  But, there comes a point where we simply must find out for ourselves, unless we enjoy the discussion of possibilities equally well. 🧐

[fas42]

3 hours ago, GeneZ said:

 

 

You are going to decide on measurements?  Who has bad measurements today?

 

It's like the public service - the most important thing is to Cover Your Arse. "I awarded the contract to the company that provided the most paperwork - that had the most impressively presented metrics, graphs all over the place ... the fact they were incompetent in getting the job done is quite irrelevant, really "

[GeneZ]

39 minutes ago, fas42 said:

 

It's like the public service - the most important thing is to Cover Your Arse. "I awarded the contract to the company that provided the most paperwork - that had the most impressively presented metrics, graphs all over the place ... the fact they were incompetent in getting the job done is quite irrelevant, really "

 I just got this the other day in a newsletter.. I does a good job of describing the different kind of persons who buy audio. I thought it was spot on. .   Interesting read:   https://www.audioholics.com/editorials/bose-conundrum

 

[GeneZ]

Nuforce is no longer in business.  The Nuforce STA 200 was a class AB amp was designed in part by Goldmund - as in the JOB amplifier. 

 

Nuprime was created to transfer the high end line of Nuforce, and to continue with only that level of product.

 

These links provide some significant measurements of some of amplifiers, and the new the Nuprime Evolution Amp..

 

https://totallywired.nz/nuprime-2/nuprime-evolution-one/

 

https://www.hifi-advice.com/blog/review/analog-reviews/amplifier-reviews/nuprime-st-10-power-amp/

[DavidL]

Just add my two-penny worth. After listening to Bel Canto and other class D amps I bought a Primare A.60 3 years ago. Absolutely brilliant - it seems to impose no signature on the music and copes happily with all genres.

[esldude]

2 hours ago, GeneZ said:

Nuforce is no longer in business.  The Nuforce STA 200 was a class AB amp was designed in part by Goldmund - as in the JOB amplifier. 

 

Nuprime was created to transfer the high end line of Nuforce, and to continue with only that level of product.

 

These links provide some significant measurements of some of amplifiers, and the new the Nuprime Evolution Amp..

 

https://totallywired.nz/nuprime-2/nuprime-evolution-one/

 

https://www.hifi-advice.com/blog/review/analog-reviews/amplifier-reviews/nuprime-st-10-power-amp/

 

Where are the measurements in those links?

[GeneZ]

1 hour ago, esldude said:

 

Where are the measurements in those links?

  

Measurements?   What ones are you looking for in particular?   Will they tell you how good/bad it will sound?

 

Some specs are given while the reviews I linked was being written.  Input impedance,  switching frequency, etc. 

 

Look.  I am biased.   The ST-10 I own.  I used to own a MC275.  Nuprime captures a unique midrange that I have only heard with tubes. Specs?  This much I found online...

 

• Power Output: 150W x 2 at 8 Ohms; 150W x 2 @ 4 Ohms
• Gain: X 28
• Input Impedance: 23.5k Ohms
• 12V trigger input. It can use any standard male to male 3.5mm (3-pin type) cable.
• Sensitivity: 0.89 V to rated power
• THD+N: 0.01%
• Frequency Response: 0 Hz to 50kHz (-3dB)
• S/N Ratio: 91dB @ 10W

 

The signal to noise ratio I believe was effected when Nuprime decided to add selective even order harmonics to capture that tube sound I mentioned.  Its the end result that counts.

[esldude]

3 minutes ago, GeneZ said:

  

Measurements?   What ones are you looking for in particular?   Will they tell you how good/bad it will sound?

 

Some specs are given while the reviews I linked was being written.  Input impedance,  switching frequency, etc. 

 

Look.  I am biased.   The ST-10 I own.  I used to own a MC275.  Nuprime captures a unique midrange that I have only heard with tubes. Specs?  This much I found online...

 

• Power Output: 150W x 2 at 8 Ohms; 150W x 2 @ 4 Ohms
• Gain: X 28
• Input Impedance: 23.5k Ohms
• 12V trigger input. It can use any standard male to male 3.5mm (3-pin type) cable.
• Sensitivity: 0.89 V to rated power
• THD+N: 0.01%
• Frequency Response: 0 Hz to 50kHz (-3dB)
• S/N Ratio: 91dB @ 10W

 

The signal to noise ratio I believe was effected when Nuprime decided to add selective even order harmonics to capture that tube sound I mentioned.  Its the end result that counts.

I've been a bit suspicious of specs by manufacturers.  Some I trust, some I don't.  Having seen some measurements over the years by Soundstage, Stereophile, and other places that is more so than ever.  

 

Now I'm not calling them wrong, but that is not quite as convincing as the reviewer having supplied us with some independent measures.  Plus those aren't fantastic specs vs some available gear.  Their okay.  THD+N is low enough probably, but not great at -80 db and that didn't say what frequency, what power or anything.  Response to -3db at 50 khz is also not great. SNR is probably alright. 

 

So I wouldn't have called those measurements. I'd have called them manufacturer specs.  Sorry for the semantic quibbling.