Audio Science Review Review

ASR replied to my Reddit post about evaluating speaker imaging by listening to mono. Link: https://www.reddit.com/r/headphones...ersy_of_amir_from_audiosciencereview/ggj0ilf/

Short version: Amir did not intend for this to sound like was referring to stereo imaging. He says he was talking about what Toole calls “apparent source width”. I don't know what to make of the word “imaging” anymore.

He also replied to the criticism of listening to the HD800S at 94dB: https://www.reddit.com/r/headphones...ersy_of_amir_from_audiosciencereview/ggj1agu/

Short version: it seems the 94dB number was paired to a specific frequency at which it is perceived as not loud; see Fletcher-Munson curves. Not sure what to make of this — for example, do the OSHA standards refer to SPL at a specific frequency?

 

Then at least he isn't that stupid. But yes, what imaging, then?

I don't really do theory much, so excuse my ignorance, but there is a thing (???) where speakers are more or less identifiable and placeable point sources of sound, whereas others are not so much. Some speakers seem to be able to do a disappearing act. There is one speaker design that specialising in not appearing as a point. I forget the name, one of those TLAs, I think, and rather pricey. Looks like a space craft. Tries to make the whole room feel like the sweet spot. Have to say that I was impressed when I heard them at someone's house. Of course, I did hear the stereo pair: had no reason to try one at a time! Edit: the make is MBL.

Aren't higher frequencies more dangerous? Maybe they are just the first to show the damage.

 

I was actually just watching videos of people with crazy car subwoofer systems that kind of answered this. It seems like the standards for damage are around 1k or in the vocal range. Sitting in a car with 150 dB at 20Hz - 40Hz is not as dangerous for hearing.*

*according to the video. Do your research to confirm, but I do think there's validity to it.

 

Anybody who's listened to a stereo before they ever read ASR would interpret "imaging" to be in the context of the stereo image produced by 2 speakers. Amir seems to have been referring to the perception of spatiality based on the directivity/dispersion characteristics of a single speaker, and in his attempt to justify his inappropriate use of the term he's now confused matters further by discussing and finding a quote about the characteristics of not speakers but rooms.

But he doesn't state this specific frequency - he says "Loudness is subjective and much of the energy in music falls in lower registers where our hearing is extremely insensitive. To wit, threshold of audibility 20 Hz is nearly 75 dBSPL! This is some 85 dB above threshold of hearing at 3 kHz!!! This is why very deep bass is felt far more than heard."

This is horseshit on multiple levels. Most of the energy in music is in the flat area of the equal-loudness curves, ie the mid frequencies; the content way down at 20 Hz will be none or almost none. Also his use of the threshold of audibility to justify his point is deceptive: the curves flatten markedly up at the volumes being talked about, where the difference between 20 Hz and 3 kHz is around 35 dB, not 85. Unless he's using a signal calibrated at 94 dB in the mids to listen very quietly to music having only bass, his arguments are irrelevant.

And as has been mentioned before - is he talking average or peaks? If 94 dB is average, the peaks (assuming normal music) will be over 100.

The OHSA standards for noise exposure are in terms of dBA. So yes, if you're listening to something that's all bass, you could add 10 dB or more to the numbers in the OSHA Table G-16 and be compliant with the regulations. Note "could" is not "would want to".

 

What? Unless he’s listening to a mono overhead or room mic, mono lps, an early Beatles or Motown album or adjusting the width on an algorithmic plate reverb (yes this is inherently wtf but real) then wtf?

 

And back when they made mono recordings, they used big ass horn speakers like Altecs and Tannoys where the distortion and treble would tear your face off at Amir volumes

 

Notice how Amir doesn't mention what the specific frequency was in his hand waving reply?

Yeah, that's because it was 425 Hz, which is quite a sensitive range for hearing:

https://www.audiosciencereview.com/...ser-hd800s-review-headphone.18424/post-602066

Note the plot references 94 dB @ 425 Hz. Immediately below the plot he mentions that he thinks a 'sufficient level' for '300 ohm headphones' (sensitivity what?) is 2 Volts, aka ~110 dB on the HD 800s, no mention of switching to 'measurement levels' just a continuation of the discussion of the output of his Samsung phone. . .

 

Yeah well bad 400-500hz can be boxy feeling on a recording or speaker. That small room or small cabinet (on loudspeaker or guitar cab) sound. Strategic 1 to 3 db dip there can sound bigger. He has no idea what he’s talking about.

 

What annoy's me more beyond them being insecure bassheads, Is them getting upset when a headphone distorts at 90db to 100db but is low under 90db. I'm sure the Clear could maybe do 6db if under 80db but that means Amir admitting his very loud SPL tests are junk.

 

I should add that many of the speaker Amir apologizes for over others, will never ever sound right due to uneven midrange. A guitar cab will never sound right. A vocal will never sit right on a JBL LSR 305. It’s impossible. It’s not even really color, the cab is straight cheaped out too much. It’s worse than the KRK Rokit 5 except for a not as bloomy port and the weird boosted high end that’s fatiguing but let’s You pick out pops and clicks.

meanwhile Amir dares to shit on much better speakers that have been around for 30-40 years like Yamaha, NHT, and ATC. And speakers that have improved a lot recently like ELAC. The Chinese company that bought them did a bang up to make a reasonable sounding product to be sold in big box stores. Nit picking any of these is what the f**k? How do you even criticize ATCs except for that the sealed two ways can be boxy and freestanding, the ones below the 50 all sound low pass filtered but that’s all out in the open, on the website and brochures. Many of these speakers have only a few flaws in reasonable use and then just scale with detail and price. You get what you f'ing pay until a certain point unless you decide to be a retard and get something with pa or Dayton drivers and shitty dsp like the present Genelecs and Kiis.

you know what? These complex crossover active monitors sound broken. Same with the equalizer controls in normal active monitors. They’re horrible and kill detail. They’re meant for atrocious rooms and huge old school mixing consoles with massive reflections. Even the shelves kill depth and transients. Now take something with a stupid complex dsp crossover like the Genelecs, Kiis, or ultra complex analog like the Neumann KH. Do you how what they sound? Dead inside. Low detail sound inside the speakers. They don’t have depth. It’s like you take a normal active monitor that sounds good in your room, flip the switches on the back to god knows what, just f**k them up to hell and back, then apply an eq in REQ or whatever half decent linear phase eq or minimum phase mastering type eq you want to make them reasonably flat sounding. You know what you get in a reasonable room? Dead inside, low detail phase scrambled speakers that sound more fucked up than a cassette despite being fuller range. This is what Amir and Ilkless like. They’re deaf idiots.

 

These I actually enjoyed, but not as much as other speakers of the same sort, here I mean Dutch&Dutch 8C and Grimms.

 

Please have a look at this post:
Relationship between Fletcher-Muson curves and Sound Level Measurements

Now with that information consider that just because the Human Auditory System is less sensitive at low frequencies doesn't alleviate damage from exposure to loud low frequencies. The high frequency detection cilia of the basilar membrane are just on the other side of the oval window in the cochlea. Low frequency detection cilia are deep down inside the cochlea far from the oval window. When presented with high levels of low frequency the basilar membrane is vibrating the high frequency cilia like seaweed in a tsunami. It may not be audible but damage is occurring.

Here are a few more references to ponder:
https://www.sciencemag.org/news/2014/09/sounds-you-cant-hear-can-still-hurt-your-ears
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4448896/

 

Frank Laico, recording engineer from Columbia Records, visited my project studio years ago on several occasions. The first one we auditioned some of the music he had recorded from the likes of Miles Davis and Thelonious Monk using genelec 8030s. He commented that something sounded seriously wrong with them.

Later we used a Synthesis Nimis tube amp + PSB Imagine B speakers. In his usual understated fashion he simply commented "Those sound correct."

 

Sounds like me with single driver IEMs sounding better than the multi driver ones.

 

Those are both high up on my curiosity list. Reviews seem to be few and far between.

 

Connected the dots in the thread for everyone.