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Announcement: ASR Will Be Measuring Speakers!

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amirm

amirm

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Geddes observes that less resolution is needed at the rear of the speaker since high frequencies aren't radiating back there but the Klippel system seems to have uniform sampling resolution?
No, there is a whole paper on optimizations it performs to reduce the number of points. Here is an example:
1578636092532.png
 

mkawa

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the room and field correction math is fascinating. but! what to measure next?
 

Rockfella

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This will be epic!
 

Matias

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Milt

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I don't sell anything. I should given so much gear I have bought that I have tested for the forum, or received as samples. Definitely could use the money. :)

I do want to measure some of the things that I owned prior to this site, but just have not had time. Dug up my vintage Optonica amplifier for example and there has been requests for my Mark Levinson DAC. Per earlier discussion, there is a shot at measuring my Revel Salon 2 speakers. I also have a Mark Levinson amp I could measure but the thing is so heavy. And has potential to blow up my dummy load. I also want to measure my Otari Reel to Reel tape deck.

Is this what you were asking?
Yes it was. How perceptive of you from my inarticulate post.
I was thinking of the Levinson amps and Salon2 speakers.
I own Studio2s & while they have been reviewed extensively, I look forward to seeing gear on this site and the resulting discussion.
Any thought of reviewing subwoofers?
I don't know the logistics.
 
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Any thought of reviewing subwoofers?
Love to measure some. Not sure what resonances they create in the garage where I have the unit and what impact that has. I will try one soon...
 

AudioJester

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Wow, those frequency sweeps are pretty quick, but loud in the Magico video.

I hope your garage is isolated from the rest of your house, or at least sealed off. That must be a lot of noise testing speakers. Thanks again for undertaking this, there must be many sacifices. Where do you park your vehicles now?

On another note, is that many full range frequency sweeps at the defined dB, in a short period of time, harmful to the drivers?
 

aarons915

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What speakers are on their way besides the Kali IN-8? Very interested in the KEF LS50, Q150 and R3. Also, @echopraxia mentioned supplying the new Sierra 2 EX and Sierra Tower with RAAL that many would be interested in I'm sure, he's local to Seattle so no delivery needed.
 
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I hope your garage is isolated from the rest of your house, or at least sealed off.
It is. At the volumes I am testing you can barely hear it inside. There are double doors to the garage which also helps.
 
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Wow, those frequency sweeps are pretty quick, but loud in the Magico video.
They have set the microphone position quite far from the speaker. That is probably the reason they are using higher volume. My scans are much closer so signal to noise ratio is excellent at the lower volume I am using.
 
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On another note, is that many full range frequency sweeps at the defined dB, in a short period of time, harmful to the drivers?
I have not listened to theirs. In my sweeps they last 2.5 seconds and no, they are hard to speakers. They are tested with chirp signals like this all the time. It is more gentle than the old way of pulsing them with an impulse.
 

No. 5

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I'm late to the party, but I wanted to add my deep gratitude for this happening. This is a huge service to everyone who's interested in, and cares about, the technical part of consumer audio.

Thanks Amir!
 

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daverosenthal

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Amir, the first couple of reviews are fantastic. The NHT one contains the key graphs I think. A couple of ideas:
  1. A good addition to the "estimated in-room response" graph might be a line showing the basic goal as defined by the Harmon work (a straight line from 20Hz to 20kHz loosing ~9db if I recall correctly)
  2. I think a distortion measurements would add a lot. Big speakers that effortlessly play loud transients are a whole different beast to little near-field monitors but the spinorama numbers will not necessarily show it. If you had a way to reference to e.g. 90db output @ 2m and show distortion by frequency, that would be sweet.
 
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amirm

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I think a distortion measurements would add a lot. Big speakers that effortlessly play loud transients are a whole different beast to little near-field monitors but the spinorama numbers will not necessarily show it. If you had a way to reference to e.g. 90db output @ 2m and show distortion by frequency, that would be sweet.
I don't want to show meaningless information. I have to calibrate the microphone first so that SPL values are correct. Then I need to experiment in controlled situation to see if the data is correct. We also need to standardize on levels we want to measure. And distance. The latter is problematic because the system is setup for near-field measurement and can't go too far back from the speaker.
 

Juhazi

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Hmm, we readers seem to have countless number of detailed measeurement/analysis requests! Modern mesurements and FFT-based analysis of measured impulse response make this possible.

The publisher must decide what she thinks is relevant, valid information, and also reliable with her measurement system. Stereophile/Atkinson has decided to not show distrtion, but some others do like Soundstage and German Stereo. Many pro-sound oriented sites/mags do and show distortion analysi, because it is a very important factor for their readers. In home hifi only small speakers and soundbars are seriously challenged with spl limits/distortion.

A good example of problems with measuremetns is JBL LSR305. It is a really cheap active speaker with flimsy cabinet and cheap components. Still it has one of the best ever measured dispersion profiles and nice sound. If we knock on it or listen to bass-heavy music loud, problems appear. I happen to have a pair of MkI which I measured, listened, opened and pimped. https://www.diyaudio.com/forums/multi-way/320206-jbl-lsr305-tweaking.html
 
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