Apparently not. Class D seems to be vastly outnumbered on the Vanity Fair... errrr... Stereophile Class A list.
But you still owe me a drink, which probably costs more than your royalty.
I will confirm in a few weeks, my last attempt with Bel Canto's never bettered my Krell 200s or Threshold S500
If true .. eureka ....
Tripath can be very good, but VERY sensitive to PSU.
Right now, i'm thinking about an other way (active) to remove the distortion of the filtering coil and the switching frequency residues.
Rick
I had thought of it. I had split the resistor between the caps equally to + and – leads.
I had done some measurements but i didn’t see any difference (with a constant load).
May be things are different with PSU load varying, or with current measurements instead of voltage measurements that I was then doing.
I have to revisit the topic.
Thanks
George
It's interesting to me to have watched the evolution of switchmode amps in relatively recent history. Initially they were thought of as a means to more efficiency, not a path (single, dual, or Tri) to enhanced fidelity. When digital storage and retrieval became prevalent, the notion of staying within the symbol domain for as long as possible occurred to many, a good number of them discussing the ideas at the Technical University of Denmark (something that led to extreme contentiousness among the participants in later days) .
Without attempting to recapitulate everything, which would take pages:
If I have my facts straight the first person out of that group to commercialize a "pure" digital approach was Lars Risbo*. The product, the TacT Millenium, was not touting efficiency as much as sound quality. It had a cool level control, which was actually controlling the power supply rails to determine the gain, and had such good bearings that it attracted onlookers at shows to give it a big spin and see how long it kept rotating.
Other graduates from that school, and ongoing research there, prompted Tim Shuttleworth once to quip that the D in class D and "digital" amps really meant Denmark.
But Risbo's amplifier was filled with big output filters, necessary to reduce distortion otherwise arising, since the product was inherently open-loop. And the power supply was elaborate, as except at zero signal and a bridge-mode output, there is virtually no PSR.
But it was a start. More at 11.
*searching for Risbo I ran across an astonishingly recent, rather gushing, and in places howlingly inaccurate IEEE piece: Class-D Audio: The Power and the Glory - IEEE Spectrum We are assured that class D is better
Without attempting to recapitulate everything, which would take pages:
If I have my facts straight the first person out of that group to commercialize a "pure" digital approach was Lars Risbo*. The product, the TacT Millenium, was not touting efficiency as much as sound quality. It had a cool level control, which was actually controlling the power supply rails to determine the gain, and had such good bearings that it attracted onlookers at shows to give it a big spin and see how long it kept rotating.
Other graduates from that school, and ongoing research there, prompted Tim Shuttleworth once to quip that the D in class D and "digital" amps really meant Denmark.
But Risbo's amplifier was filled with big output filters, necessary to reduce distortion otherwise arising, since the product was inherently open-loop. And the power supply was elaborate, as except at zero signal and a bridge-mode output, there is virtually no PSR.
But it was a start. More at 11.
*searching for Risbo I ran across an astonishingly recent, rather gushing, and in places howlingly inaccurate IEEE piece: Class-D Audio: The Power and the Glory - IEEE Spectrum We are assured that class D is better
With a d'Appolito configuration, it is not so much a matter of accidents happening, but rather of some predictable laws at work. Understanding these laws and staying within their confines, this configuration may bring advantages for some setups. Not in full range though, just as mid/high section of a multiway.
It worked well for them. TI bought them and integrated the technologies into TI's product lines and, per the CEO of TI, is completely delighted with the results, great management skills and a line of excellent amplifier products.
Our perch on the "Hi End" is starting to fall way behind what is happening in the mid price range. Multi-amped speakers with really sophisticated crossovers and eq doing things not even imaginable a few years ago. Decent drivers plus the sophisticated tuning possible can make for genuinely good speakers. The bigger challenge today is deciding what constitutes a good speaker in terms of response, balance etc. The ability to make it is not a challenge.
PMA, as far as I can tell you fancy measurements yourself and you've called out JC a lot of times in this thread for talking about subjective, intangible, pseudo-engineering parameters.
So, please, enlighten us and point out parts of the measured performance presented (or left out) here:
http://www.hypex.nl/docs/NC400_datasheet.pdf
...or here:
http://www.hypex.nl/docs/NC1200_datasheet.pdf
...which indicate we are talking about a "horrible" and "not high quality audio" product.
Also what percentage of amplifiers marketed in the HiFi/HiEnd market do you consider better than the aforementioned units, and what is the average cost of said amplifiers?
Mind you, I'm not asking for a subjective evaluation - though I don't think you could provide one anyway since, judging by your stance, I gather you wouldn't even come near the NCores lest they permanently damage your hearing or something.
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I couldn't agree more, and this is a lesson that should be learned by high end audio, or it might perish i.m.o.
More loudspeaker manufacturers should start to offer the option for their speakers without passive Xover, but with an electronic xover/compensation box instead. And amplifier designers should start designing high end 4 channel amps for 2ways and 6 or 8 channels for moreways. But since both speaker and loudspeaker builders are locked into their present markets of big shiny boxes with solitary functions, this might not happen in time.
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