Audio Science Review Review

FTFY.

 

No expert myself, but the crux of it seems to be that one speaker already tells you how the imaging will be in an actual stereo configuration. Sort of.

But Im with you. To sit and listen to one and think you can know how a pair will image is bold. You can easily hear directivity and even evaluate tone, but it seems a bit ridiculous to rely only on that when you can easily just run two and hear it directly. The on paper way is fine, but hes sitting there with a perfect opportunity to make direct subjective correlations and for whatever reason completely avoids it.

But thats kind of his bag. Extrapolate the entire experience. And then turn aroynd and make subjective commentary that doesn't line up with the data presented, or even the conclusions extrapolated.

Like a lot of things with him, the bare fundamentals arent ALL terrible and wrong. Its just that his execution is inconsistent and his approach is stubbornly myopic, to the level of totally missing the point. In his mind his methods and results are as complete as possible already, so anything else is superfluous. "Please don't discuss this for pages every time I bring it up."

Come to think of it, he says some variation of that a lot.

 

The distortion he is listening to is ridiculous. He is often listening through always active limiters in active monitors at that level. The lamo amps he uses (and in the powered Monitors he likes) are distorting horribly and most of the drivers in the speakers he is using can’t take that kind of abuse long term. He is not reviewing huge woofer towers, PA system subs, and horns. He craps on the speakers meant to survive abuse in a studio and would break them anyway. He got massive thermal compression on a genelec and bottomed out an ATC woofer with a bass shelf off either his crappy crown amp or his pretty much unrepairable mark levinson. He shat on ATC and Quested all the time yet praised McIntosh, B&W, and every middling active piece Harman and Neumann KH release but then derides the setups that replaces all of that stuff as you go up in budget because it’s just better everywhere. Better drivers in better cabs driven by better amps with no compromises (No Computer modeled Wave guides and dsp) for being poorly setup in Amir’s living room and garage. He seems to be the type of guy who would blow out a big subwoofer with distortion, dc offset, or just sustained volume.

 

My understanding is that the Harman people did tests comparing evaluations of two speakers to evaluations of a single speaker, and got essentially identical results, so then did the remainder of their testing on a single speaker, as they had confidence the results would transfer.

Which seems sensible, but it's also possible they missed a variable there. I think Toole and co have done great work, but it'd be really nice if another well funded lab tried to replicate/disprove their results.

 

Can you explain this a bit more? I thought the whole point of ASR was to use things which measure imperceptible distortion. Are we talking about a different kind of distortion, one not measured? I understand ASR favors class D power amps — does this suggest that all class D amps cause the kind of massive and possibly driver-damaging distortion?

 

So that was my summary of parts of a half-remembered thread from AVS, but I went digging a bit, and found that what I said was not quite accurate. Actually the deal is that (Toole says) stereo listening obscures some flaws in some program material, so mono listening gets you the clearest evaluative picture. The paper is apparently called "The Effects of Loudspeaker Directivity" from 1985, but if you google "effects loudspeaker directivity toole 1985" the first result (at least for me) is a presumably-not-legit PDF of his book, and he talks about that paper plus additional context from later years in chapter 8. The relevant summing-it-up paragraph:

 

yes. all modules have a significant rise in distortion well beneath their advertised wattage. they also usually use switchers that can't provide enough current and all have a big rise in imd in the treble.

compare this to class a and ab amps, which are typically advertised (if not made in the PRC and bought off of AliExpress) with the wattage meaning X watts RMS at Y ohms with Z distortion. Compare the emotiva and ATC 300 watt amps for exmaple.

Emotiva XPA-2 gen 3
300 watts RMS/channel; THD<0.1%; 8 Ohms; two channels driven.

ATC P2 Pro:
Output Power: 300W (8 Ω, 1kHz, continuous. avg., both channels driven)
THD: >0.002%/-95dB (8 Ω, 1kHz, -1dB below full Power)

Of course the ATC smokes the Emotiva like a brisket and can get way louder than the Emotiva. So will Bryston, MC2, shit from the 80s, and most things not class H or G or whateve the emotiva power supply is.

Now let's go to CLASS DICK
Let's take the most popular diy amplifiers, the hypex ncore 400 and ti tpa3255
First of all we're looking at shittons higher THD, IMD, and noise for the same wattages.
https://www.diyclassd.com/documenten/download/860
Just from the specsheet you can work out why it's a f'ing turd even compared to 70s-80s power amps. Not only does it have fullscale IMD in the air band (none of us can hear that high but it will f**k with shit below it where we can hear), rising distortion at 200w, treble transients will be shitty, etc. you’re better off with the emotiva
https://www.ti.com/product/TPA3255
The TPA 3255 shits the bed around 100w in almost all cases. 300 and 600w my ass.


You basically need at least two to three times the wattage of a class ab amp for class d. You don't even save any money at that point. It's just smaller and lighter and still more distorted. For subwoofers only and only with a real power supply.

 

lol no.

Sorry, it probably wasn't clear, but I was responding to an earlier post on the thread wondering what Harman was thinking in doing the eval on a single speaker. Amir's claims are beyond my understanding.

 

Makes sense. Thanks!

This is a bit off-topic, but what’s your take on LM3886-based amps? I was thinking of building one, and was attracted to it being class AB and therefore possible to fit into a more compact case than one of Nelson Pass’s class A beasts for more output power. But if it has hidden crap like weird distortion swings not on the basic charts, I’ll reconsider.

 

It seems that he has heard the sound of one hand clapping.

 

It was a very-quiet, quite nearly silent, whooshing that swept above his head and between his ears, barely agitating the stray wisps of grey matter lain in between and chancing upon, but wasting, the opportunity to spark a semblance of thought via the great caverns and valleys that hallmarked and pockmarked the spaces between aged and worn neurons.

 

There’s no point in spending over 500 bucks to diy given what’s available on the used market. Gainclones are mediocre and ncore 400, and tpa3255 sound okay on low wattages but if you have 200-300 to spend on something good and old and 100-200 on restorations or mods, that old thing will shit on class dick and lm3886

 

Imagine an ASR YouTube channel:
https://www.audiosciencereview.com/...nnel-for-more-income-source.18448/post-602286
The comments section will be... entertaining.

 

Because Amir’s absurd sub bass boost and ear-splitting listening levels cause the Clear to clip, he “cannot recommend them.”

 

At least some of his "acolytes" acknowledge the silliness of his Clear claims.

I'm more amused with his ASR headphone target curve.

I don't know why I visit that website. Most of his conclusions are absurdly flawed and arbitrary.

 

It is a dumpster fire, can't openly enjoy the ER4/HD600 flat bass without being told "I guess you hate bass". They really can't grasp at 6 ~ 12db the bass overwhelms everything making everything sound like crap, It the reason why the 7K area on Harman is got a high boost too.

/r/Headphones is still acting like kids about the Clear review being a dud.

 

I read that as ASMR and wondered... yeah, why hasn't someone monetized that yet? It would basically be the same as those demo disks with the 30 second intros to each 60 second musical excerpt, telling you what wispy or tactile thingamabobbers to listen for. Just add some husky close mouthed breathing during those intros and you're golden.