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Odds are, the AVR is good enough anyway unless you're trying to drive something either very efficient and have noise issues, or woefully inefficient floorstanders. In other words, just use the speakers jacks you have. If you can't use a Hypex, you're not going to identify a Class D that is...

Generally, no. Only IOM seems to have one that works with low level pre-outs reasonably well, with a variable gain over 30dB. NAD standardizes around 28dB I believe. They're among the highest. Most of cheapy integrator outputs just provide a bunch of largely worthless additional low and...

It's got to be basically just a voltmeter. That's the only way you're going to get one of these things to work, so they move in proportion to something and it has to be measuring something to move the meters. (Okay, fine, you could actually make it accurate by spending money on engineering for...

Let's just quote Audioholics on it, since those are more of a feature/product review than ASR which is more of a measurement dataset. I know Amir has noted it at least once ( can't find it except where it shows up in measurements), but Audioholics puts this or something similar is a bold box in...

Never set a receiver to 4 ohm mode. The Audioholics reviews all tell you not to do this and why, as do many ASR reviews. You severely limit power by doing this. That mode exists solely to pass regulatory testing and does limit power. Has nothing to do with any protection circuit.

I'm sure it's been mentioned, but just look up what Douglas Self calls "class B" in his handbook. It's just an optimized bias point which actually involves very little bias current. On further reflection, that's probably all they mean and they call it Class B because Douglas Self says they...

So what I just said, basically. I'm just adding that 15kHz still provides a pretty good correlation for Class D, and still generally tends to be indicative of a good or bad twin tone IMD. Hence, when twin tone is not measured, which it often is not, the 15kHz still provides a useful technical...

I'm horribly confused why you keep posting this. Are you trying to say the 15kHz distortion measurement has zero meaning? If so, that's just technically wrong. If you're just trying to say the harmonics are not audible, that's true. But also irrelevant. No one says they are. The point is...

Perhaps the best thing to do is not to speculate about other's motivations. Personally, I don't find it all that offensive, but I'm not very easy to offend! :D Really, though, let's get back to the technical. What I haven't seen anyone say a word about is whether my impression that when...

Possibly a good backstop. Unless you're trying to tease out what causes a particular distortion, in an AB amplifier you may as well just hit it with 20kHz (or 15kHz) to assure yourself there is nothing untoward going on. If it passes that, it probably passes everything else you can throw at...

I believe everything he said was qualified by "appears to be", "if" "came across as", "have to believe that", "seems like" and "my interpretation is". The reality is that most people cannot interpret amplifier measurements well, so they rely on the subjective commentary and the little "panther...

I'm going to return to this amplifier for just a bit, because it stands out on a chart I'm building, and its a relatively inexpensive name brand product. I said before that it was linear. This is also a good spot for this until I have the time to do a more detailed post about amplifier...

If you want a screen in this form factor, I don't think you can do better for less or even similar price. True, the analog section could be better, but if you're all digital, this is already great, particularly if the room correction actually works. Hook this to a Hypex and you're kinda at end...

I was pointing out simply that most people aren't going to care how a PWM Class D works, and what various measurements may mean in that context. PMA does, so I responded to him. There's not really anything to agree or disagree with, unless someone seriously believes high IMD is desirable...

Agreed, and I don't know that it's a known fact yet that taking the feedback after the output inductor necessarily solves everything that was seen in your excellent set of posts and measurements on the Aiyima A07. Obviously, it helps, in that the feedback can deal with some of the nonlinearity...

Again, bad 15kHz THD is just an indicator of a potential problem. Maybe it's fine, maybe not. Your money, your gamble. Buy this for whatever the feature set is, not for the "great" technical performance of the amplifier, which does not exist.

This is where I'll beg to differ. They voted how they did because they are technically ignorant about power amplifier design, by and large. To be clear, that's not a criticism. Most of those who understand anything about amplifier design tuned out long ago and stopped commenting because they...

The test results. It's actually .2% at 15kHz. Typo first from me (corrected) then John. We know from prior comments from Hypex this is a hard problem to solve in Class D. This amp hasn't solved it. We also know it can cause IMD which is much more obnoxious to the ear than low order...

.20%, .08%, and .04%. Audible or not, that translates right into "not good" by any reasonable metric. It also suggests it is prone to IMD, which in fact it does exhibit. Audible? I'll leave that for someone else to judge. But as an amplifier it's not impressive. This is objectively bad...

Remember that you can't use a cheap SPL meter to measure peaks. The sample rate isn't high enough to capture a 20ms transient. You would need one that complies with the "impulse" standard, which costs $500 an up. So, the "peak" reading could be wrong. I just checked the REW docs, and it also...