[RonN5]

Long Rumored - Finally Arrived

[Don_S]

Ron,

Thanks for the pictures. Any other information? Power, cost, inputs (balanced or SE), black option?

[mresseguie]

Ron,

By 'arrived', do you mean in your home, or production has begun?

There's a good thread on Agon discussing these new Class D mono amps.

Don,

If memory serves me correctly, the retail on these will be $5000/pr (but I may be wrong). 100w/ch into 8 ohms.

[Don_S]

Ron,

By 'arrived', do you mean in your home, or production has begun?

There's a good thread on Agon discussing these new Class D mono amps.

Don,

If memory serves me correctly, the retail on these will be $5000/pr (but I may be wrong). 100w/ch into 8 ohms.

Thanks for the info. I believe Ron means they are showing at the currently ongoing (Feb 18-20) show in Florida. Florida Audio Expo 2022.

[RonN5]

Saw them at the show… from the Atmasphere website:

http://www.atma-sphere.com/en/classD.html

$5400 per pair

[Don_S]

Saw them at the show… from the Atmasphere website:

http://www.atma-sphere.com/en/classD.html

$5400 per pair

Ron,

Thanks for the link and information. Were they being used (on what speakers) or was it a static demo?

[Phil A]

Ron,

Thanks for the link and information. Were they being used (on what speakers) or was it a static demo?

Goldnote stuff per this video - https://www.youtube.com/watch?v=U2mEyAALXaM

[Phil A]

From the video, it looks like these speakers - https://goldnoteusa.com/product/a6-evo2/

[Tyson]

Saw them at the show… from the Atmasphere website:

http://www.atma-sphere.com/en/classD.html

$5400 per pair

Yummy!

[Freo-1]

Can't wait to see the reviews and the measurements.  Should be interesting.

[RonN5]

Phil… you are correct about the goldnote speakers… they were somewhat lacking in midbass which probably contributed to the top end sounding a little bright… but thanks to the Atmaspheres, big soundstage.

[TomS]

I spent quite a bit of time in the Unique Home Audio room 515 - Gold Note, Acoustic Signature, Atma-Sphere. The speakers are Gold Note S6, ~$9k and a beautifully made Italian design. I didn't find any brightness or midbass problems, rather found it very balanced and enjoyable to listen to for an extended time, at least with vinyl. The Atma-Sphere GaN amps were used the entire time I was there and sounded very good. Ralph obviously knows what he's doing, and it is great to see him apply his considerable experience and talent to a class D design. Well done!

[RonN5]

One more thing about the Atmasphere amps....I went to this room three times, they were cold to the touch each time.

[Freo-1]

One more thing about the Atmasphere amps....I went to this room three times, they were cold to the touch each time.

It's the GanFET performance. 

[Tyson]

It's the GanFET performance. 

Yes, GanFETs are no joke.  For the first time in my life I'm excited about Class D amps.  I just spent a lot of money on some Kismet monoblocks, otherwise I'd probably buy a pair of these.  What an exciting time to be alive if you are an audio enthusiast!

[goryu]

These run at 500KHz. The only real benefit over mosfets at this rate is less heat, which isn't really an issue with current mosfet class d designs like those from Purifi, which runs cool and has distortion well below most anything else on the market. The designer of the Atmosphere GaN amp said as much himself on another forum:



"At only 500Khz, what is the advantage of using GaN?



"In a nutshell, reduced distortion and less heat than MOSFETs, not like that's much of a thing. "

[Freo-1]

These run at 500KHz. The only real benefit over mosfets at this rate is less heat, which isn't really an issue with current mosfet class d designs like those from Purifi, which runs cool and has distortion well below most anything else on the market. The designer of the Atmosphere GaN amp said as much himself on another forum:



"At only 500Khz, what is the advantage of using GaN?



"In a nutshell, reduced distortion and less heat than MOSFETs, not like that's much of a thing. "

He also said that this was the first SS amp that can sound as good or better than tube amps.  Hi is going to post additional measurements to better understand how the amp actually performs. 


The Devialet Expert Pro 440/1000 has some amazing distortion measurements.  They also sound fantastic. 

[Tyson]

I think there's also something to be said for less feedback.  Not everyone is sensitive to the affects of feedback on sound, but I am. 

[Freo-1]

Although this article is dated,  much of what says remains applicable.  There are some very good reasons many still prefer valve amps over sand amps. 


The fact that a long time tube manufacturer came up with this  amp approach says something.




  https://spectrum.ieee.org/the-cool-sound-of-tubes#toggle-gdpr

[ACHiPo]

Hmmm wonder how they’d sound driving Sound Labs?