Do ClassDAudio Amps Have Proper Decay Of Notes?

georgelofti,

Another innovation, meaning a different melange of approaches in the Technics amps are the way they handle jitter. The Reference Class SU-R1 can handshake in digital mode (with some form of Ethernet) with the SE-R1 until the amplifier does a conversion to analog to drive the speakers....Note that the amplifier uses a linear power supply! The final innovation is the LAPC or load adaptive phase calibration. This seems like the F1 "boost button" that makes the Technics two top ranges so pleasing to reviewers. I have an acquaintance in the industry (he does not have a dog in the fight though) who has heard the Technics new range in the context of a magazine review although he was not the reviewer. He is a degreed engineer by trade and is pretty sanguine about "breakthroughs." He thought the LAPC circuit was astounding with a range of box speakers.
I expect to be auditioning the Technics SE-R1/SU-R1 after the CES madness calms down. I'll be using my analog preamp as well as digital direct sources. Speakers will be SoundLab U-1PX Consummates and perhaps some other unusual speakers.  Let's see if they can handle those puppies, as a regular amp and with the LAPC enabled.  I will report back. 

@ivanj

Dear Ivanj,

Have you had a chance to test the new reference caliber Technics digital amp&preamp combo with your electrostats, and if so would  you kindly share your impressions?

Thanks so much....

Ancient thread here, but I have to chime in. I recently did a DIY Hypex nc500 implementation with one of their switch mode power supplies, and the amp, which is connected directly to a DAC (in this case Teac UD-503 with variable output and remote) that serves as a pre-amp. I've also used several other DACs including PS Audio Digital Stream III, various Cambridge Audio (both Azure series DACs) and an ebay Sabre 9038PRO DAC, also with remote and volume control. My previous amplifiers Krell, a Musical Paradise SET tube amp, Marantz separates, various Onkyo integrated and separates, "vintage" Technics, and others. 

The Hypex kit deserves every bit of "hyp" it gets. Seriously I can't imagine anyone who has ever listened to one (including with swapping op amps and stuff) could say that the sound quality suffers from the switching frequency or that decay is a problem. In fact I built this little kit as an experiment and because a friend basically 'forced' me to buy them off of him, which cost me about $1400 total, including a chassis/case. In the end, I sold my Krell KAV-400xi because it just didn't sound as good (and my tastes veer toward neutral and no emphasis on any particular frequency range) with any of the music types I listen to, not to mention that, as others have noted about Class A or AB transistor amps or even tubes, the Hypex runs cool to the touch even after hours of play.

There is never any fatigue and there is always sufficient power for even previously very challenging transients. As one example, on William Orbit's electronic classic, "Water From a Vine Leaf" - streaming and played on my CD transport/DAC combo - there is one moment where all the bass, chorus and rhythm comes in at once after a prolonged quiet passage. This is hardly a great track to test the typical "audiophile" criteria like soundstage and precision, but in terms of the ability to convey pure power and energy into a room at every frequency equally, there is no comparison between any of the previous amps I mentioned and the Hypex. Just amazing, really. 

Before I come off as some kind of Hypex fanboy, I do not listen to much challenging classical and my tastes in sound profile lean toward power, impact and clarity. So I haven't run every type of music through this system and my speakers aren't really "high end" - for example the best ones I've tested are the  KEF LS50, JBL Studio 590s (amazing, BTW - totally underrated), Wharfedale Jade series, B&W 600 equivalents, Elac UB5 (the ones that DO NOT deserve all the hype). But I challenge, or suggest anyway, anyone to put a good class D amp like the Hypex to the test for a few days in your own system. The only reason I can think of that anyone would hate the sound is if you're looking for "sweetness" or other unnatural coloration. That said, the Hypex gives my tube amp a real run for its money on midrange clarity and puts out a holographic soundstage (without super wide extension to the sides tho) with no emphasis on any particular sounds/frequencies. With the JBL Studio series compression drivers, voices are surreal and there is an intimacy that I have never heard from any other setup, including at hi-fi consumer shows or in showrooms. 

If you're interested in what you are or are not missing, it's 2018 and you really should give a solid Class D amp a try.  BTW, someone said that Class D is not "digital" which is partly true, but PWM is a digital signal processing technique, so it's understandable for those amps to be called "digital" especially from a marketing angle. 

My Emerald Physics 100.2 SEs do (in spades), but they can only give you what's upstream