Class D amps that are superior to all or most?
Its also impervious to weird speaker loads causing it to oscillate because its already oscillating!However, the driven device forms part of the output filter and thus effects the frequency response. Tube amplifier frequency response also suffers driving widely variant loads. Depending on the interaction, the results can be chalk or cheese. In all things audio, the whole system and the room affect sound quality. |
I can mod your PS Audio 1200 amps to sound way better. The modules are basically stock (they only remove a coupling cap they don’t need because they already have Rel-Cap capacitors after the tube stage and they remove a resistor on the board that allows a higher impedance so the tube stage will drive it better). Benchmark does not make Class D amps. Class A/B with switching power supply. The Tsunami amps (I believe) are the $4750 amps from Legacy. They use stock IceEdge modules.....same as PS Audio 1200....PS Audio ($6000 the pair, needs upgraded tubes) adds tube front end. Again, I can modifiy the Legacy amps to sound way better. You can buy a dual mono IceEdge amp from Rouge Audio in Italy delivered to your door for $1600.....$3150 cheaper than the Legacy amp. This can be modded, as well. https://en.rougeaudiodesign.com/product-page/studio-n-10dm The output filter in a class D amp has very little effect on the frequency response. Please see Stereophile reviews where John Atkinson measures this. The output impedance of a lot of class D amps is seriously low and only rises at high frequencies to levels that are still below many class A or class A/B amps (certainly way below any tube amp). Please read and learn. The Vera amps are very, very similar to VTV here in US....the VTV amps using Purifi modules can be bought for as little as $999 delivered. Way, way cheaper than the Vera amps......again the VTV amps can be modified for way better performance. You more you search and read and learn......you will realize that you don’t need to spend a whole lot of money these days for great sound. As good as modified Purifi and IceEdge sound......my sense is that they are not as good as the $7500 AGD Audio Audion mono GaN amps........so, if you have that kind of coin and 85 watts is enough for you than this amp may be the current ticket to ride. However, If AGD made the amp into a dual mono stereo amp and put all the circuitry inside like everyone else (including no fake tube thang, no flight cases, no upgraded power cords) then they could sell it for $3500. So, whatever you buy today will be equaled or bettered for less down the road.....which is great news, really. |
D tech and it's hybrids are still in their infancy in terms of development with regards to 'high end' audio. Since the latter social group is basically small population-wise, the equipment for now will demand a stratospherically lofty price for those adopting it.This was true 20 years ago. But right now the tech is pretty mature if you look at it using the technology development sigmoid curve. We're not expecting our initial class D entry to be over $5000.00 yet its making similar power to class D amps that are $18,000.00 (Technics, for those keeping track). However, the driven device forms part of the output filter and thus effects the frequency response. Tube amplifier frequency response also suffers driving widely variant loads. Depending on the interaction, the results can be chalk or cheese.I think you might have a misconception here! Its true that the output filter is affected by the load. But it won't change the FR significantly because of two factors. First, the load affects the Q of the filter. What this means is with lower impedances the filter broadens a bit and is less effective- so you might see bit more of the residual (sine wave at the switching frequency). The second is that in a self oscillating amplifier there is so much feedback that phase shift and the audio passband FR are unaffected. Quite literally there's enough feedback to correct for issues that might arise if the filter is operating at a lower Q. In our prototypes and in our Beta production amps we're not able to measure a difference in frequency response between a 16 ohm load and a 2 ohm load. |
Ralph, Are you using tubes on the input....or is it discrete solid state or integrated circuits? Have you tried all kinds (types like toroid or enclosed, wire wound or foil...better wire quality, directionality of the wire, cryoing the coils, whether you run the signal into inner or outer winding on an air core, etc.) of different iron core and air core coils on the output? Everything makes a difference. |
