Good Class D amps ??

[barrows]

Jeff Rowland Design Group Model 825

[Ralf11]

58 minutes ago, barrows said:

Jeff Rowland Design Group Model 825

 

$32,000

 

 

[barrows]

1 hour ago, Ralf11 said:

 

$32,000

 

 

Yes, out of my league!  But the thread is about good Class D amplifiers, this is one.

[Ralf11]

Right !  I put no $$ restrictions on it, but as a 2o issue, I am collecting a list of amps to replace my old Sunfire with, and would like to economize, partly just to fulfill my Cheapskate expectation bias...

 

So far, I think I'll rule out the Vidar (hum issues)

 

List includes:

PS Audio (Class A to D) $1,500

Benchmark ("magic" AB) $3,000

 

[R1200CL]

12 minutes ago, barrows said:

Yes, out of my league!  But the thread is about good Class D amplifiers, this is one.

 

Would love to see a comparison test with those expensive clad D amps. 

 

Mola, Mola, Theta, and those other expensive once mentioned. 

As long they all use the Ncore 1200. 

 

 

[Summit]

17 hours ago, Ralf11 said:

Right !  I put no $$ restrictions on it, but as a 2o issue, I am collecting a list of amps to replace my old Sunfire with, and would like to economize, partly just to fulfill my Cheapskate expectation bias...

 

So far, I think I'll rule out the Vidar (hum issues)

 

List includes:

PS Audio (Class A to D) $1,500

Benchmark ("magic" AB) $3,000

 

 

I have not personally heard Auralic Merak mono power amplifiers, but I know some people that really like them, and they are not ultra-expansive. Just like MBL they are hybrid class A and class D. Chris Martens liked them with his Magnepan speakers.

 

http://www.theabsolutesound.com/articles/auralic-merak-mono-power-amplifiers/?page=2

[firedog]

18 hours ago, barrows said:

Yes, out of my league!  But the thread is about good Class D amplifiers, this is one.

Sure, but the interesting question is; where are the "levels"?

 

Pretty much everyone (except GUTB) thinks the Nord, Apollona, and PS Audio amps that don't sell for more than $3000 MSRP are very good amps by any standard.

 

How much more do you have to spend to get a significant improvement? Something like the $5000 Merrill?  Is it even noticeably better? Or one of the amps in the 10K neighborhood? It would be interesting to hear from someone who has compared or upgraded within Class D.

[barrows]

2 hours ago, Summit said:

 

I have not personally heard Auralic Merak mono power amplifiers, but I know some people that really like them, and they are not ultra-expansive. Just like MBL they are hybrid class A and class D. Chris Martens liked them with his Magnepan speakers.

 

http://www.theabsolutesound.com/articles/auralic-merak-mono-power-amplifiers/?page=2

I get a little annoyed when i hear about these so called "hybrid" amps.  I have heard this term used for things like Devialet, etc. Pretty much every class D amp I am aware of is actually a "hybrid" design in terms of this!  All class D amps have a relatively normal, input gain stage, which is accomplished using normal linear circuits, usually running in class A-so every class D amp is a "hybrid" by this definition!  Devialet started this naming proposition and it is a bit misleading!

 

For example, all nCore modules require an input buffer in front of the class D switching stage.  My NC-400 DIY amp has a fully discrete circuit, linear input stage with discrete voltage regulators as well.  The NC-1200 as used in the Merrill amps has an opamp IC based input stage, with discrete voltage regulators, and a linear circuit driving the switching output stage, etc, etc...

The Nord One Up amps use discrete class A opamp circuit, with discrete regulators in its input stage.

 

I think we need to stop using this "hybrid" term to describe various class D amps, they are all this way!

 

The Meraks use Hypex uCD modules for their output stage, powered by a linear power supply with a custom input stage designed by Auralic.

 

There is a comparison of the Merak amps with the newer Nord One Up amps at 6moons in the Nord review for those interested in where the older design Meraks stand in relation to newer class D tech (N core). 

 

[Ralf11]

ok

 

how about the term "gain cell" ??

[monteverdi]

6 hours ago, barrows said:

I get a little annoyed when i hear about these so called "hybrid" amps.  I have heard this term used for things like Devialet, etc. Pretty much every class D amp I am aware of is actually a "hybrid" design in terms of this!  All class D amps have a relatively normal, input gain stage, which is accomplished using normal linear circuits, usually running in class A-so every class D amp is a "hybrid" by this definition!  Devialet started this naming proposition and it is a bit misleading!

 

For example, all nCore modules require an input buffer in front of the class D switching stage.  My NC-400 DIY amp has a fully discrete circuit, linear input stage with discrete voltage regulators as well.  The NC-1200 as used in the Merrill amps has an opamp IC based input stage, with discrete voltage regulators, and a linear circuit driving the switching output stage, etc, etc...

The Nord One Up amps use discrete class A opamp circuit, with discrete regulators in its input stage.

 

I think we need to stop using this "hybrid" term to describe various class D amps, they are all this way!

 

The Meraks use Hypex uCD modules for their output stage, powered by a linear power supply with a custom input stage designed by Auralic.

 

There is a comparison of the Merak amps with the newer Nord One Up amps at 6moons in the Nord review for those interested in where the older design Meraks stand in relation to newer class D tech (N core). 

 

Devialet's ADH is not just a class A input stage (as more or less all class D amps) followed by class D but they claim the class A stage generates the full voltage for the speaker output and 4 class D amps work in parallel to generate the necessary currant. I wish Devialet's technical explanations would explain more than their old white papers. Also I remember reading that the 4 class D stages are arranged in a fashion that cancels switching noise and therefore does not require filtering in the final output stage.

Also as the input stage is directly the DAC it is impossible to compare Devialet to any N-core etc. amp.

[Ralf11]

54 minutes ago, monteverdi said:

 the necessary currant 

 

Black Corinth

[jabbr]

7 hours ago, barrows said:

I get a little annoyed when i hear about these so called "hybrid" amps.

 

Yes Class "D" is not the same as "direct digital" and so is "hybrid" by definition. In direct digital the digital signal itself is amplified, voltage and current and then typically the digital carrier is filtered. Conceivably the digital signal itself might be fed into certain speaker components but implementations are proprietary.

[jacquesr]

I strongly suggest you check Hattor.com

 

I have a passive preamp, and it works gloriously. Arek is a great guy.

Even the design of the gear is neat.

 

 

[opus101]

1 hour ago, monteverdi said:

Devialet's ADH is not just a class A input stage (as more or less all class D amps) followed by class D but they claim the class A stage generates the full voltage for the speaker output and 4 class D amps work in parallel to generate the necessary currant. 

 

My understanding of Devialet is they're rejigging the old Quad concept of 'current dumping' where instead of the 'current dumper' being classB, its class D. So 'hybrid' seems a perfectly reasonable term for it to me. 'Hybrid' is only about the output stage, not about the preceding signal stages (which in many classD amps with opamps, are classAB)

[mocenigo]

On 03/04/2018 at 3:12 PM, Ralf11 said:

 

They have a stereo amp under $1,000 USD, correct?

 

Well, the ones based on the NC252MP and NC502MP modules should (I just had a look at the web page) and if you order the Icepower 1200AS2 based one from outside the EU it should be very close to USD 1000 as well.  If you want NC500 + custom buffers, of course they will be way more than USD 1,000...

[mfsoa]

Digital Amp Co can sell you outstanding Class D amps for ~ $1K.

[DancingSea]

On 4/8/2018 at 10:23 AM, Ralf11 said:

ok

 

how about the term "gain cell" ??

 

Keep the PS Audio Stellar M700 monoblocks in mind as well.  FWIW, class A rating....

 

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

[GUTB]

On 4/3/2018 at 2:57 PM, Ralf11 said:

that appears to be NYA:

 

 

Not Yet Available

 

I listened to their ToTL model Big Cherry MEGAschino in monoblock mode through JTR speakers at AXPONA today. I’ve never heard the JTRs before, they are 3-way with double 10" drivers and a horn-mounted compression tweeter. I don’t know what DAC or preamp used, I saw a few little boxes in the dark so it was probably Cherry models doing that.

 

They drove the JTRs with authority. Strong dynamics, power and controlled bass. I didn’t get the best seat in the room so I couldn’t judge soundstage much, but I didn’t detect overt flatness or point-source problems. Sadly, it was a lo-fi experience: low inner detail resolution, results in the sound missing that sense of reality.

 

I may go back tomorrow to look into the system details to see if the lack of resolution is due to the DAC, pre, etc.

[GeneZ]

On 3/26/2018 at 4:51 PM, Ralf11 said:

is the NuPrime ST-10 Class D??
$1595

 Its the finest amp I have ever listened to ......  That does not mean there is nothing better.  I am sure there must be.  I just have not the means to go beyond the ST10 and still remain feeling justified for my desktop nearfield system.  I tried the NuForce/ JOB.... and several others.  And,  I have owned tubes as well.   Your mileage may vary....   And, yes.  The ST10 uses very little electricity compared to a typical amp of equal power.

[oneartist]

I have two M700's fed by Direct Stream DAC w/Bridge II. My Magnepan 3.6's  gloriously produce effortless music. 

[OneNoteSam]

Another vote for the Bel Canto monoblocks. I auditioned them against an Audio Research Ref 75. They were not put to shame... 

[GeneZ]

Update.... Besides the NuPrime ST10 I mentioned...   also a very good sounding amp is the PS Audio S300.  Very good balance of sound.

[oneartist]

PSAudio is flexible on their pricing structure. If you buy from them directly you can always trade up to a newer model and get full credit for what you paid on the old one. Or, you can buy the pair of $3000 PS Audio M700 mono blocks for $1900 like I did from  HighPerformanceStereo.com. When I crank these amps up, my Magnepan 3.6's sound amazing. For the price, I don't think you can do better than the M700's. I'm sure the PS Audio S300 can be had for a similar discount. 

 

 

[jmpsmash]

Has anyone compared the PS Audio Stellar M700 and the Hypex NC400?

 

I had the NC400 for more than a year and I love the detail, neutrality, dynamics and esp how it manage to control the woofer so well. Unfortunately my NC400 just blew (totally my fault) and I am thinking of moving to the M700 but I don't know if it will retain the same qualities. They will be driving a pair of Mezzo Utopias.

 

[ShawnC]

40 minutes ago, jmpsmash said:

Has anyone compared the PS Audio Stellar M700 and the Hypex NC400?

 

I had the NC400 for more than a year and I love the detail, neutrality, dynamics and esp how it manage to control the woofer so well. Unfortunately my NC400 just blew (totally my fault) and I am thinking of moving to the M700 but I don't know if it will retain the same qualities. They will be driving a pair of Mezzo Utopias.

 

I have a pair of M700s.  It's the only class D I've tried at home.  When compared to my my Emotiva XPA Gen2 stereo amp, the M700s go deeper with the sound stage and more defined in the midrange.  They are also louder.  Where they do lack is in the treble range.  Not as defined as any other class A or AB amp I've had.  I just bought PS Audio BHK250 amp.  That arrives in the next week, so I can compare the M700 to the 250.  I'd also consider Bel Canto's class D amps, from what I've heard at the dealer they are superb but cost more then M700s.