Atma-Sphere Class D Mono blocks

[Atmasphere]

I am not sure Ralph fully appreciates the ramifications of his claims.

uh-oh!! Whu'd I say??

 

[DonH50]

uh-oh!! Whu'd I say??

If you're going to hang yourself, hopefully it is on a glider.

 

[Gregadd]

If you're going to hang yourself, hopefully it is on a glider.

Or a surfboard.

 

[Gregadd]

Obsolescence- What happens when something equal and/or better, less complicated, and less expensive, is produced.
See Wikapedia

 

[Bjorn]

We are actually trying to get the distortion down as much as we can since its always barrier to transparency/detail. So zero intentional distortion. As I've said before (I can't speak for other designs), it worked out that the non-linearities in the amp (the encoding scheme and the deadtime in the output section; the latter of which dominates the distortion generation) tend to generate lower ordered harmonics rather than higher ordered. So it has a prominent 2nd and 3rd harmonic, its distortion spectra being somewhere between that of an SET and our OTLs in that regard (IOW, the 2nd is dominant but not as much as seen in an SET, whereas in our OTLs the 3rd dominates), but considerably lower overall; about 1/100th that of an SET and about 1/10th that of our OTLs.

Have you provided any measurements of the amplifier?

 

[morricab]

Just ordered a pair from USA Tube Audio, Scottsdale, AZ.. In a month or so, after maybe 300-or-so hours of burn-in, and in spite of NOT being a quick-to-hear-differences GEA, I'll be able to characterize their sounds compared with my much-loved and -improved Atma-Sphere MA-1s and also my 60Watt Allnic A-6000 PSETs.
View attachment 102099

And what do you hear differently between the Atmaspheres and the Allnics?

 

[thomask]

Orchard Audio Starkrimson Stereo Ultra Amp Tour!

I would love to audition this amp. I'm looking for an amp upgrade. Can I be added to the audition list? I have sent you a pm.

forums.stevehoffman.tv

#287

Interesting comparison between

Starkrimson Ultra class D
Class D Audio Mini GaN 3
Benchmark AHB2
Atma-Sphere S-30 amp

It would have been more interesting to have included Atma D amp.

I am in line for auditioning Starkrimson Ultra class D.

Maybe I can give my opinion around February.

 

[Atmasphere]

Have you provided any measurements of the amplifier?

Yes.

 

[Bjorn]

Yes.

And where is that? Couldn't find anything on your website.

 

[Gregadd]

The Snake consuming itself. It is important to point out here that I have no negative image of snakes. They are a magnificent, beautiful creature with an obviously lethal self-defense system.
I use this an analogy.
By declaring Class D amps as good or better than his tube he has rendered his entire tube amplifier line obsolete. In essence his own company is consuming itself. It should be quite disconcerting to his customer both present and future.
Of course, there is always the possibility I am overreacting.
Snake consuming itself

 

[Gregadd]

utput power
100 watts per channel into 8 ?
200 watts per channel into 4 ?

Input Impedance
100 K? balanced/single-ended
Output Impedance:
~0.010 ?
Input
2.15 Vrms for full output
Gain
22dB
Power Bandwidth
1Hz-20KHz
Frequency response
1Hz-20KHz
Distortion
Total Harmonic Distortion less than 0.1% at full power.
IM distortion less than .04% at full power.
Feedback
35 dB
Power consumption
5 watts at idle (per channel)
Dimensions & Weight
13" deep x 11" wide x 3" high (33 x 28 x 8 cm) per chassis
14 lbs (6.35 kg), per chassis
Warranty
Three year general coverage

 

[Atmasphere]

The Snake consuming itself. It is important to point out here that I have no negative image of snakes. They are a magnificent, beautiful creature with an obviously lethal self-defense system.
I use this an analogy.
By declaring Class D amps as good or better than his tube he has rendered his entire tube amplifier line obsolete. In essence his own company is consuming itself. It should be quite disconcerting to his customer both present and future.
Of course, there is always the possibility I am overreacting.

When we embarked on this project, it was not with the intention to replace our tube amps. It was to sort out exactly how good a class D can be. This was because I heard one that was very good at AXPONA. I realized that any amplifier manufacturer simply had to sort this out; class D at that time had been a rising star in high end audio for 15 years.

When we got it going several things were obvious right away:
1) our market was going to be larger because a wider range of speakers could be used with our amps
2) the amp sounded better than our most popular amps, suggesting that it could supplant them at lower cost

Of course the latter thing flies in the face of the Veblen Effect but we've been doing that for nearly 50 years.

We felt that we should give it the same look as our other products, but owing to the fact it didn't need any adjustment or meter, we opted for the look that our preamps have. So the construction is similar and it doesn't look like the denizen of a mancave. At home I have them sitting on top of my speakers, something I could never consider with the tube amps.

As to whether we are a form of Auroboros; hard to say; the class D has been our most successful product entry in the history of the company whereas Auroboros is more a symbol of the circle of life. Am I being too literal?

 

[jeffreybehr]

And what do you hear differently between the Atmaspheres and the Allnics?

I guess you didn't actually read my post. I quote: "Just ordered a pair from USA Tube Audio, Scottsdale, AZ.. In a month or so, after maybe 300-or-so hours of burn-in...".. Since 'a month or so' has not transpired, I have no idea what differences I'll hear.. Or were you thinking/writing about some other Atma-Sphere poweramps?

 

[christensenleif@msn.com]

I´m sure it commented somewhere, but what speakers do you use Ralph?

 

[Atmasphere]

I´m sure it commented somewhere, but what speakers do you use Ralph?

My speakers at home are the Classic Audio Loudspeakers model T-3, equipped with field coil midrange and woofers. They are 16 Ohms and 98dB. My speakers are a bit taller than the stock model to increase the cabinet volume; they are flat to 20Hz.

 

[microstrip]

utput power
100 watts per channel into 8 ?
200 watts per channel into 4 ?

Input Impedance
100 K? balanced/single-ended
Output Impedance:
~0.010 ?
Input
2.15 Vrms for full output
Gain
22dB
Power Bandwidth
1Hz-20KHz
Frequency response
1Hz-20KHz
Distortion
Total Harmonic Distortion less than 0.1% at full power.
IM distortion less than .04% at full power.
Feedback
35 dB
Power consumption
5 watts at idle (per channel)
Dimensions & Weight
13" deep x 11" wide x 3" high (33 x 28 x 8 cm) per chassis
14 lbs (6.35 kg), per chassis
Warranty
Three year general coverage

These are specifications, not measurements.

 

[Atmasphere]

These are specifications, not measurements.

Huh. We measured them- so yes, they are measurements.

 

[microstrip]

Huh. We measured them- so yes, they are measurements.

Well , they list in the specifications section of Stereophile reviews , in highend jargon measurements are supposed to show real data, not just limits.

If you send me a pair for evaluation I will be able to measure myself - although you risk that I will not return them!

 

[Atmasphere]

Well , they list in the specifications section of Stereophile reviews , in highend jargon measurements are supposed to show real data, not just limits.

If you send me a pair for evaluation I will be able to measure myself - although you risk that I will not return them!

Hm. Maybe that's the issue I've been seeing. On the one hand, the 'only tube' people have trouble understanding that the class D sounds the way it does, OTOH the measurement guys don't like to see what we measured. FWIW this was never a problem with the tube amps!

 

[Gregadd]

Well Ralph since you have gone live with this experiment, we will see how it plays out in real time.
I think the snakes is taking a huge gamble. It is trading short term nutrition for long term survival. Certain animals are able to regenerate parts of their anatomy.