Could Class D really be that good?

Whilst Discussing OP Amps, the OPA 1656 is one known to be selected for use in place of other OP Amp's.    

I first heard about the 1656 from a description of the LSA Discovery Warp 1 amp. I bought some and put them in place of the 1612s in the Purifi factory input board. Did not like them, not as musical as 1612. You might love them....but trust only your OWN ears.....not what others say. Most people act like sheep.....just following and repeating what others say somewhere. How about the "You just need to have the impedance 10 times higher for a preamp to amp match".....another words, a 100 ohm output impedance is fine driving an amp with 1K input impedance. Who the heck made up that statement? But you see it repeated on forums over and over. My 50 ohm output impedance source sounded better with a 150K load than it did with a 50K load. How about bypssing caps....."The rule is that you need a bypass cap that is one tenth the value". What a bunch of nonesense. You need the value and type that sounds best with the main cap. Many use .02uf to bypass large caps. You must listen to know. You must love to really know love. Please Love more......more often and more deeply. Makes you happy.

Did you not read what I said?  I said the amps will all measure the same.....this is absolutely true.  While it is true that when changing parts the distortion changes....because all noise and veils are distortion.  However, you CANNOT measure a change in measured distortion when changing passive parts. 

@ricevs Oh I read what you said. But it was false, as is the above statement. You certainly can measure a change in distortion when passive parts are replaced! The idea that this isn't so is laughable.

Yes, some will laugh at their own folly.  I would llike to see you prove this statement: "You certainly can measure a change in distortion when passive parts are replaced!"  Show us the beef!  Where are your graphs?  Show us the volumes of statements from other high end audio designers who have tested this and show graphs.....please.......I have NEVER in my entire life heard of any high end audio designer, engineer, manufacturer say this except for you.  If this statement were true then every time a manufacturer made the sound better by upgrading the jacks, fuses, wires, resistors, damping of parts, capacitors, power supplies, power supply parts, etc. into infinity.....they would state it.....and they would show graphs to prove it. They would say.  We found a better cap.....we replaced our super last years cap with a new one and not only does it sound better but the distortion went down .001 percent of distortion.  But no one has ever said this....because you CANNOT measure the distortion of most parts. 

A Furutech AC inlet sounds better than the one you use.  If you replaced yours with a Furutech would your amp measure better?  (By the way, the Furutech ones with Rodium plating sound different from the ones with gold plating....same with their NCF technology.....do they measure differently?  does Furutech claim such?).  Removing the steel hardware on your power supply transformer and raising it off the chassis improves the sound.  Can you measure that?  I listened to three different brands of tiny .1 percent nichrome surface mount resistors that all looked the same and all of them had slightly magnetic end caps.  This was a 75 ohm resistor on the output of a Crystek clock.  One brand sounded much better than the others.  Did that change the measurements of the Oppo I was modding?  Hardly.

If you are using junk parts....like bad electolytics, ceramics, very inductive resistors and put them in a sensitive place then not only will the device sound bad but it will measure worse than using a better made part.  But what high end manufacturer uses junk ceramics as a feedback or coupling cap?  The knowledge on caps and their sound and distortion was first published in Audio Magazine by Marsh and Jung back in 1980....I am sure you remember that.  That article changed what high end manufacturers did.  They realized that bad dialectric caps sounded bad.....so they all changed to film caps and the high end electrolytic caps market (Elna, Blackgate, etc.) started.  Conrad Johnson started using all film caps in their power supply (no electrolytics whatsoever).  However, every brand of super high end film caps sounds different (including all the various models from the same company).  For instance....Clarity cap makes many models of film caps.  They claim the better ones "sound better".  There is no mention of lower distortion measurements on their site.  If they could measure lower distortion....they would brag about it....obviously.

Ralph, I wish you the best.....but if you are going to sit all by yourself on that tiny branch and saw away......well, eventually.....you fall.  

Here is an article about using really bad parts in portable audio devices......yes, those seriously bad parts can be measured.......However, we cannot measure the parts that are used in high end audio......unless you are Ralph....he must have super sensitive test equipment no manufacturer of better sounding parts has.

I don't believe it's necessary for components to be of poor quality to show disparities in measurement. Take the Fosi V3 and Aiyima A07 as examples. Both of them use the TI TPA 3255 module, but Fosi utilizes quality passive parts like Japanese/German capacitors and inductors. Both use the same stock op-amp (active). These disparities in the quality of passive parts are sufficient to produce audible differences in THD, as shown in ASR measurements.