Thanks for all the useful info on the sound of the new A-S Class D amps. As you continue to listen and compare these amps to other high quality amps, please provide some additional comments on their ability to convey a fullness and richness of tone, especially in piano, voice, acoustic guitar, and upright bass. When I hear about an amp's ability to convey great detail and transparency, I worry that the added detail may come at the expense of a natural fullness of tone. I've heard this effect in several good quality interconnects that provide excellent detail but don't have quite enough "meat-on-the-bones" in the upper bass and midrange to provide the balanced sound I like to hear. Any additional comments in this area of performance would be much appreciated.
Atma-Sphere Class D… Amazing
Today I picked up my Atma-Sphere Class D Amps. These aren’t broken in yet. And they are simply amazing. I’ve listen to a lot of High End Class D. Some that cost many times what Atma-Sphere Class D costs. I wasn’t a fan of any of them. But these amps are amazing. I really expected to hate them. So my expectations were low. The Details are of what I’ve never heard from any other amps. They are extremely neutral. To say the realism is is extremely good is a gross understatement. They are so transparent it’s scary. These amps just grab you and suck you into the music. After I live with them some and get them broken in. And do some comparisons to some other high end Amps Solid State, Tubes and Class D’s, also in other systems I’ll do a more comprehensive review. But for now, these are simply amazing amps.. Congrats to Ralph and his team. You guys nailed on these.
Showing 8 responses by sdl4
I've learned a few important things from this thread. I've been impressed by the consistently positive comments about the sound quality of the new Atma-Sphere Class D amps from users who have owned or heard these amps in a variety of audio systems. I have been extremely impressed by Ralph Karsten's intelligence, patience, and skill in explaining the design principles he's used in creating and building these amps. He's also been effective in correcting misconceptions about his amps by posters who have been quick to question Ralph's choices in component parts, business models, and retail pricing. At the same time, it has been concerning to read posts that question Ralph's honesty and transparency in providing sufficient information to potential customers who want more detailed measurements of the Class D amp. A number of basic measurements have been provided on the Atma-Sphere website, as is typical for Ralph's other amps. The amount of measurement information is more than provided by some manufacturers and less than provided by others. To suggest that Ralph is being insufficiently transparent about the functioning of this amp (for some dark reason) is silly and irresponsible. Ralph deserves greater respect than that, given his long career as an honest and talented designer of electronic gear. Based on the user opinions in this thread, as well as reading reviews and measurements of other Class D amps (some GanFET and some MosFET based), I look forward to listening to both the Atma-Sphere Class D amp and one of the Orchard Audio amps in my own system. Other listeners may prefer to focus on other products, but the Atma-Sphere and Orchard amps appear to offer the best balance of sound quality and cost in relation to my current budget and needs. As usual, other users may have different opinions. |
I'm guessing that "kuribo" is the same person who repeatedly posted very similar comments on another online audio forum using the name "goryu." That discussion was focused on comparing the sonic differences between Ncore modules and Purifi modules. The poster in question stated over and over that personal opinions about sound quality are meaningless. Naturally, statements like that are consistently effective in pushing audiophile "buttons." |
You may have already covered these issues earlier in this thread, but could you please explain a little more about the following two issues with regard to your Class D amps? 1. I noticed that the switching frequency for your amp is 500 kHz while several other GaNFET amps use a higher switching frequency. Did you decide that 500 kHz represented a "sweet spot" for switching frequency in your design? Does the choice of higher rates have unwanted side effects that can adversely affect sound quality? 2. What factors entered into your choice of a toroidal power supply rather than a SMPS? What number and size of capacitors did you use in the power supply and how did you decide on the amount of storage needed? Thanks for any additional info you can provide! |
@atmasphere Thanks for the helpful comments in response to my questions about the choices of switching frequency and power supply for your Class D amps. |
Can you comment on the fullness and tonal richness of the A-S Class D amps in your system? So many of the new generation of Class D amps (whether GanFET or MOSFET) receive praise for their resolution but are rarely described as outstanding in terms of warmth, smoothness, and richness of tone. I'm thinking of the naturalness and realism of voice and stringed instruments (especially guitars and upright bass) that emphasis tonal quality in the midrange and bass. My personal tastes value tonal balance over high-frequency pyrotechnics, but not everyone shares my tastes. Thanks for any further thoughts based on your extended experience with the A-S Class D amps. |
@atmasphere Thanks for letting me know about the HiFi+ review. I was able to track it down, and it presents a very positive view of the sound quality of the A-S Class D amps. Going forward, these monoblocks will be high on my list of amps I'd like to audition in my home system. Are you still planning to build a version with somewhat higher power output? |