• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Announcement: ASR Will Be Measuring Speakers!

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The Spinorama specifies 10° rotations, some people would even perform measurements with 5° rotations.
Klippel advertises the time-saving with 1° angular measurements. I would doubt that most loudspeakers need a very high order of harmonic expansion given that most drivers are run with a very limited range, not too far above ka. The structures of the wavefront would be limited, which gets to my point - how much resolution do you think you will need to capture the features of the wavefront? How much time do you want the measurement procedure to run for?
 

rgpit

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Love to see the Harbeth 30.1, 40.2, or the SuperHL5 plus tested.
 
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amirm

amirm

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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
 

Rockfella

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This will be epic!
 

Matias

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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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amirm

amirm

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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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amirm

amirm

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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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amirm

amirm

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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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amirm

amirm

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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.
 
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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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