Love my Gold Note PA-10's and my Canor AI 2.10 both check all the boxes, my class A-B tube amp sits collecting dust.
Expanding the Class D Conversation: How Would You Characterize Their Differences?
Expanding the Class D Conversation: How Would You Characterize Their Differences?
I'm currently trialing the NAD M23 (1st gen. Eigentakt-based), and I find it intriguing enough to want to understand it better — which means understanding the broader sonic landscape of class D. So I'm crowd-sourcing.
In a recent exchange, the estimable Ralph Karsten (Atma-Sphere Music Systems) made two comments that stopped me cold. For those who missed it, here's what he said:
"IME, class D amps vary in sound more than tube amps, which is to say, quite a lot."
"IMO there is a bigger difference between various class D amps than you hear between various tube amps. IOW just because you heard one class D amp says nothing about how the next one might sound."
Link: https://forum.audiogon.com/posts/2885828
As I think through this more carefully, these are genuinely important claims. My own experience with tube amps confirms that they produce audibly distinct characters across topologies and designs. If Ralph is right and class D exceeds that range, then generalizing from one class D experience to another is even more hazardous than I assumed.
One specific question for Audiogon members:
If you have a Class D amp or have compared class D amplifiers, how would you describe their character(s)?
Here are some criteria I use:
- Frequency balance — Is the tonal response even across bass, mids, and treble, or does it favor certain regions?
- High-frequency texture — Are the highs extended and smooth, or edgy, grainy, and fatiguing?
- Bass definition — Is the low end tight and articulate, or loose and bloated?
- Midrange character — Does the midrange feel present and natural, or recessed and thin?
- Transient speed — Does the amp respond quickly to dynamic attacks, or does it sound sluggish and rounded?
- Dynamic range — Does it scale convincingly from quiet passages to loud ones, or compress the difference?
- Soundstage width and depth — Does it create a convincing three-dimensional image, or sound flat and narrow?
- Image specificity — Are instruments and voices placed precisely, or do they blur and wander?
- Background noise floor — Is the silence between notes actually silent, or is there grain, haze, or hash?
- Long-term listenability — After an extended session, do you want to keep listening, or has something been quietly fatiguing you?
If you can include relevant system context — room, speakers, preamp — please do. Those variables will help me interpret what the amp itself is contributing.
I'm less interested in rankings than in understanding what Ralph mentioned, namely the [vast] range of sonic signatures class D is capable of. Eigentakt, Hypex, Pascal, Purifi, GaN-based, etc. — all fair game.
Price is no constraint here — I'm interested in the full range of what's out there.
- ...
- 355 posts total
Let me try to reply. foggyus91: Thanks for sharing—it's telling that your Class A-B tube amp is collecting dust now; that's a strong practical endorsement of the pairing you mention. mapman: Good point about specificity; I'll use those tools. The idea that newer Class D tends to resemble the best tube or SS amps but in smaller, more efficient packages captures what people seem to be discovering. yyzsantabarbara: Thanks for the clarification—version 6.5 without glare is useful to know, and your side-by-side comparison of the GanFet with the CODA #11 next week should be revealing bluethinker: Your framing—whether modern Class D delivers the emotional experience we started this journey for—is exactly right, and your AGD experience validates that. kirkwallace: Thanks for the detailed scoring —exactly the kind of systematic feedback that helps. I'm very curious about your Gato DIA 400S report. earthbound: Let us know about your Orchard Audio monoblocks; a good additional data point on the broader Class D landscape. A local audio reviewer I know has them with Spatial open baffle speakers and they're pretty magical. dwest1023: That's helpful—the Nuprime bringing you closer to the music; the preamp pairing matters enormously. doni: Your experience mirrors bluethinker's—the "just keep listening" quality and lack of harshness with Atma-Sphere suggests a really good design. Have you heard the AGD or are you just comparing it to Atmasphere? |
From what Ive read in the past from owners of both AGD MK3 and Ralph's Atmosphere's the AGD is more Tubey and Ralphs design has more grunt like SS. Earlier in this post Ralph stated that his amps are more "tube-like" although he didnt compare his amps to AGD MK3. So I guess one must decide for themselves. |
@hilde45 - For additional context, my primary system includes: QLN prestige 3 speakers: Known for a somewhat laid back and musical sound signature. Cardas Clear speaker cables and interconnects Mad Scientist Prime USB cable Puritan 156 with the Puritan Ultimate cable |
- 355 posts total