Beyond the Ariel

[Pano]

BTW - thanks very much Lynn, for your great explanation of the phenomenon, or parts of it. I was beginning to believe I' have to resort to the tired old "If you haven't heard it....." I was really surprised that some folks here had not heard it.

Just as you describe with phono stages and DAC analog stages, if the rest of the chain is also up to the task, wonderful things start to happen. "Magic" is just a fun way of describing it. It isn't magic, just very good (over) engineering. But it can be surprising enough the first few times you hear it to seem like magic. Surprising at first because because you've never heard a system do that. But it starts to make sense had sound quite natural very fast.

Maybe this little side discussion will help point some DIY folks down a path they didn't know existed.

Originally Posted by peterbrorsson

With the better riaa, the noise from badly handled LP's seemed out of phase and totally disconnected from the music. Cheaper riaa, the noise was right in your face.

A very good example of what I was talking about.

[soongsc]

Originally Posted by Bill F.

Dr. Geddes,

What's your Pioneer's model number?

That's a tough question.

[jacq.]

''The amp is a Pioneer DSX-V912 - a receiver. The point is that it was on sale at Costco for $150.00''

[Bill F.]

Google is stumped. Maybe VSX-V912?

[markus76]

Wouldn't it make more sense to ask Earl why this receiver is so good and what application fits best? What were the parameters he measured and why are they important?

Best, Markus

[gedlee]

Originally Posted by markus76

Wouldn't it make more sense to ask Earl why this receiver is so good and what application fits best? What were the parameters he measured and why are they important?

Best, Markus

Markus

Asking questions like that might make one sound like 1) they actually care and 2) that they don't already know the answer.

But here is the answer anyway!

In very high efficiency loudspeaker one is very often at extremely low signal levels within the amps circuitry. This makes a very insidious type of nonlinearity called crossover distortion (where the signal does not go smoothly through zero because the upper and lower sections of the amp are not well aligned) very problematic (audible). Typical measurements of THD versus level won't show this type of distortion at all. They will show high level nonlinearities, but for a high efficiency loudspeaker these signal levels mean very high SPL and very low perception of nonlinearity. Bottom line they aren't a problem. In a typical THD versus level chart the low level measurement is all noise - completely masks the effect of interest. One has to measure the nonlinearity of the signal well down into the noise floor. This can be done, but its not a standard measurement. There was a thread that Migeo posted above that describes the technique and shows some results.

[gedlee]

Originally Posted by Bill F.

Google is stumped. Maybe VSX-V912?

Yes, my typo.

[soongsc]

Originally Posted by Bill F.

Google is stumped. Maybe VSX-V912?

Man, that was a quick one. We somehow switched from CD player to Amp. I'm getting too slow for this.

[CLS]

Just out of curious, I found a manual of a (maybe) similar series model here:
http://www.scribd.com/doc/299744/Pio...-owners-manual

(I can't find the exact model. Their model numbers are changing fast.... )

A big WOW! I've been away from such AV equipment for quite a while, now they are so sophisticated! I almost fainted when seeing the rear panel. Is that a honeycomb or multiple rocket launcher? Another bigger WOW is that built-in "phase correction function" !! (see p11 in that manual)

Wow .... speechless....

[john k...]

Originally Posted by soongsc

Man, that was a quick one. We somehow switched from CD player to Amp. I'm getting too slow for this.

Actually it was slew limited phono riaa eq to slew limited CD to crossover notch distortion in amps.