ieales
Stating that 1.5GHz will solve all the problems is as silly as saying a 10MHz Class AB bandwidth has to sound better than 100KHz.
Not "all" but the major one, that point to listeners having issues with the upper/mids and highs.
Cheers George
The Truth about Modern Class D
All my amps right now are Class D. ICEpower in the living room, and NAD D 3020 in the bedroom.
I’ve had several audiophiles come to my home and not one has ever said "Oh, that sounds like Class D."
Having said this, if I could afford them AND had the room, I’d be tempted to switch for a pair of Ayre monoblocks or Conrad Johnson Premiere 12s and very little else.
I’m not religious about Class D. They sound great for me, low power, easy to hide, but if a lot of cash and the need to upgrade ever hits me, I could be persuaded.
The point: Good modern Class D amps just sound like really good amplifiers, with the usual speaker/source matching issues.
You don’t have to go that route, but it’s time we shrugged off the myths and descriptions of Class D that come right out of the 1980’s.
I’ve had several audiophiles come to my home and not one has ever said "Oh, that sounds like Class D."
Having said this, if I could afford them AND had the room, I’d be tempted to switch for a pair of Ayre monoblocks or Conrad Johnson Premiere 12s and very little else.
I’m not religious about Class D. They sound great for me, low power, easy to hide, but if a lot of cash and the need to upgrade ever hits me, I could be persuaded.
The point: Good modern Class D amps just sound like really good amplifiers, with the usual speaker/source matching issues.
You don’t have to go that route, but it’s time we shrugged off the myths and descriptions of Class D that come right out of the 1980’s.
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@guidocorona Class D, as analog as it has been, was always the bastard design. Many, many thanks to Guido to lending his splendid ears to critic the prototypes Oganesson amps line from Merrill Audio and also his generosity with excellent suggestions which some of which have been implemented. There are a few items with Class D and switching frequency is not one of them. Although the GaN transistors allow for faster switching, it is really all the removal of dead time, overshoot, and ring that has resulted in the exquisite nature of the GaN amps. Switching at a higher frequency only introduces more problems then it solves. I have a thread introducing the ELEMENT 118 Power amplifiers on tour. Feel free to take your best Class A amp or any other amp to compare with the ELEMENT 118. Currently you can do that at distinctivestereo.com in New Jersey, or HearEverything.nl in Europe or audiogenese.fr in France. More sites to come in the US. As noted earlier, issues with prior Class D was deadtime, overshoot, ring, and to add to that the heavy use of feedback to reduce distortion. With the ELEMENT 118 Power Amplifiers and the Oganesson line of amps, the dead time is zero. (Trivia: Oganesson is the ELEMENT 118 in the periodic table). That means no dead time at all. This takes any argument away from Class D whatsoever. The rest is design - reducing overshoot and ring means designing the circuits and PCB to bring the parasitic inductance and capacitance to a point where it has no or very little influence on the board. Finally the last piece of magic in the ELEMENT 118 Power amplifiers is that it has zero feedback - it is an open loop design. This frees up the system much like an open baffle speaker system does to speakers. We are shipping in limited quantities so you can look for reviews coming. But why read about anything about Class D when you can hear it for yourself and compare it directly with your amps. This is an open invitation to anyone who can travel to NJ. I hope to have more sites soon. Hope that helps the Class D conversation. A bit more on GaN Transistors. They are fast, allow great switching, limited to a few vendors like TI etc. However put a Bugatti in the hands of a neophyte and you still cannot win any races. GaN Transistors in itself, while providing the technology to finally make Class D the best, still requires a whole lot of design challenges behind it. But yes, it is the future. |
Georgy, You misinterpreted what I said about mosfets.........The category that mouser put these new GAN devices in was under "mosfets" (they have no category for GAN devices yet)......this is why I said they were not mosfets......so in case you read their thing real fast, you might think they are mosfets. Which is why I suggested downloading the data sheet. So, the one going off half cocked is...... Also, I think Merrill has a great point......maybe we don’t need higher switching frequencies.....just less overshoot, dead time, ringing via circuits using super high speed output devices (GAN). The use of parallel output mosfets (like the older Icepower amps) makes it worse with even more capacitance. The ICEedge modules have one pair of output mosfets that give 1200 watts a channel into 4 ohms. Icepower also claims they have "continuous dead time compensation". Maybe these two things are part of what makes the new ICEedge modules so good. Surely, this is not zero dead time.........but I will say these modules implemented right are really sweet. |
Thank you so much Merrill! Indeed I had suggested a few small things... I believe that you actually implement my recommendation to use 20A IEC to maximize stability of connection with heavy power cords.... Well, at least now, if anyone complains about 20A inlets, you can refer their lamentations all to me *Grins!* And yes, the Element 118 prototypes I played with were already exceptional performers, even with their pre-production circuits and assemblage! BTW, have you published pricing for Element 116 and 114?
Saluti, G.
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