"Things that cannot be measured"

[ahofer]

We should probably have a queue of people that will jump down other people's throats for saying something silly. It will save time and repetition

 

[rdenney]

Distortion doesn't mimic venue acoustics, echo, reverb, time delays
DSP can mimic that.

I dunno. A lot of my experience with rock music in my youth was with bands trying to out-muscle each other on stage using the likes of Phase Linear amps driving A7 cabinets. I expect there was plenty of distortion happening then, or at least plenty of clipping.

Music listening for me as an older adult has been mostly unamplified. For that, I have only the distortion of my aging ears--amps can't help that.

Rick "KSTR got there first" Denney

 

[solderdude]

But that's sound reinforcement issues not venue aspects (echo, reverb, tonal aspects)
These sound reinforcement issues are not even remotely anywhere near the -60dB H2 and -80dB H3 of 'audiophile' tube amps.
They would wish to come close to that.
They had more than several percent of nasty distortion.

 

[Tom Danley]

I dunno. A lot of my experience with rock music in my youth was with bands trying to out-muscle each other on stage using the likes of Phase Linear amps driving A7 cabinets. I expect there was plenty of distortion happening then, or at least plenty of clipping.

Music listening for me as an older adult has been mostly unamplified. For that, I have only the distortion of my aging ears--amps can't help that.

Rick "KSTR got there first" Denney

I am not sure, I was in live sound in the 70's and on and off since and am in large scale sound now..

What would say is in general concerts are a lot louder and have a lot more bass. At the same time, having a computer full of audio processing tools, is not the same as musicians that can play their stuff live like the recording which used to be more the norm..

Also regardless of the concept, pile of boxes, a checkerboard array or banana array (as systems progressed from the 70's) , all other things being equal, the larger the number of cabinets, generally the worse the sound quality and voice intelligibility (per Hopkins-Stryker).

Logically too as a single musical sound event should not arrive spread out in time according to the distances to each source

 

[egellings]

Tube "goodness", if there is such a thing, would not multiply like gain if fed through a succession of amplifiers. It's like a spice that tastes good in tiny amount, but would quickly ruin the food if overdone, like a pound of turmeric on my Sunday morning omelet.

 

[j_j]

Logically too as a single musical sound event should not arrive spread out in time according to the distances to each source

Well, a properly designed array should not do that. Array design is not actually that incredibly hard. How to make constant-beamwidth arrays with a particular apparent point of origin is now pretty much old hat.

 

[TLEDDY]

This is tiresome.
His genius friend likes tube and vinyl sound. So what? Stop whining about that.
Anyway Amir said you need to be trained for a successful blind test. Not everybody has the time and energy for that.

Gentlemen:

This thread is titled “Things that cannot be measured“, so I tossed in an anecdotal report. I point out my signature and my response to the “one man’s opinion “—- “Exactly!”

As to vinyl, he has not owned a turntable in a decade, rather all CD and Tidal streaming. He simply does not like vinyl.

Subjective opinions are just that; I subscribe to this site for the objective view. I try to understand why some object to measurement based evaluation. My friend‘s opinion on my Benchmark preamp and bridged amplifiers reflects his thoughts on tubes vs solid state- obviously we do not agree. I do not debate religion, politics or others intimate preferences; I will continue to post opinion statements on “Hi-fi” reproduction.

Tillman

 

[krabapple]

This is tiresome.
His genius friend likes tube and vinyl sound. So what? Stop whining about that.
Anyway Amir said you need to be trained for a successful blind test. Not everybody has the time and energy for that.

I disagree with Amir, in the case where we are testing an individual who ALREADY CLAIMS they can hear a difference between A and B -- sighted. They claim to be already 'self-trained', in effect. A simple level matched blind test , sans training, but otherwise under conditions they say they can hear the difference...will suffice to test *their* claimed prowess.

We aren't talking laboratory science in this case; we aren't testing a general proposition. We're basically administering a 'hearing test' to an individual.

 

[krabapple]

Gentlemen:

This thread is titled “Things that cannot be measured“, so I tossed in an anecdotal report. I point out my signature and my response to the “one man’s opinion “—- “Exactly!”

As to vinyl, he has not owned a turntable in a decade, rather all CD and Tidal streaming. He simply does not like vinyl.

Subjective opinions are just that; I subscribe to this site for the objective view. I try to understand why some object to measurement based evaluation. My friend‘s opinion on my Benchmark preamp and bridged amplifiers reflects his thoughts on tubes vs solid state- obviously we do not agree. I do not debate religion, politics or others intimate preferences; I will continue to post opinion statements on “Hi-fi” reproduction.

Tillman

If your anecdote's aim was to demonstrate the proposition that even a 'genius' amp designer can make generically dubious claims about audio: success!

 

[Tom Danley]

Well, a properly designed array should not do that. Array design is not actually that incredibly hard. How to make constant-beamwidth arrays with a particular apparent point of origin is now pretty much old hat.

Hi JJ
I suppose the issue is how one is looking / what one is looking at. I have not measured a CBT but i have heard them and made a synergy horn which has similar dispersion behavior but doesn't radiate as individual sources or incur the excess hf loss or what ever it was called in Don's papers..


With the concert system based arrays used in large rooms, ball fields and sports stadiums etc, one could adjust each element to the nth, so that what arrives at your microphone and in at least one ear is from all the sources in each box in sync and your impulse response and phase looks like one arrival, like a single driver.


The issue is, because each source has an individual path length to the mic or ear and source phase response, what you hear or measure changes as you move around and if the wind blows, you hear the comb filtering inherent in the array's destructive / constructive interference principal of operation.

The down side is the correction for mix position is not right everywhere else, the best case is some kind of average.
The fact that the sources never do add completely, especially if the array is curved (when they generally radiate more acoustic power sideways than forward) is why they need delay rings, no way to have a working distance of 400-800 feet with a concert array.
Line array folk lore says you need them for "throw".

Best,
Tom

 

[j_j]

Hi JJ
I suppose the issue is how one is looking / what one is looking at. I have not measured a CBT but i have heard them and made a synergy horn which has similar dispersion behavior but doesn't radiate as individual sources or incur the excess hf loss or what ever it was called in Don's papers..


With the concert system based arrays used in large rooms, ball fields and sports stadiums etc, one could adjust each element to the nth, so that what arrives at your microphone and in at least one ear is from all the sources in each box in sync and your impulse response and phase looks like one arrival, like a single driver.


The issue is, because each source has an individual path length to the mic or ear and source phase response, what you hear or measure changes as you move around and if the wind blows, you hear the comb filtering inherent in the array's destructive / constructive interference principal of operation.

The down side is the correction for mix position is not right everywhere else, the best case is some kind of average.
The fact that the sources never do add completely, especially if the array is curved (when they generally radiate more acoustic power sideways than forward) is why they need delay rings, no way to have a working distance of 400-800 feet with a concert array.
Line array folk lore says you need them for "throw".

Best,
Tom

Actually, Tom, there are solutions that provide an appropriate impulse response over a wide area. This is not the usual arrangement for high-power arrays, because it impacts power handling, but the solutions exist, and have in fact been implemented in low-power arrays very nicely. Doing this in a high-power array is not actually that difficult, but the array structure is most certainly not a uniformly spaced array.

There's a paper by Jim Flanagan from 1985 that talks about a mike array that does that. The mathmatics and such are the same for speakers, I've built one (out of 2" drivers, though, it was low-end limited) that worked surprisingly well without individual driver compensation. (yes, it involved frequency sensitive shading of each driver with a 4K non-constant-delay filter, but the design wasn't too hard to come by)

 

[TLEDDY]

If your anecdote's aim was to demonstrate the proposition that even a 'genius' amp designer can make generically dubious claims about audio: success!

Thank you...QED

 

[Phoney]

Durability? Buying something that measures really well but doesn't last long is not the best if you're not the type to change gear often. It's not allways easy to know how durable something is if it hasn't been on the market for long.

 

[mansr]

Durability can be, if not measured, at least estimated. It is common to stress-test products by running them in conditions that accelerate ageing, such as high ambient temperature or supply voltage above normal.

 

[Frgirard]

Durability can be, if not measured, at least estimated. It is common to stress-test products by running them in conditions that accelerate ageing, such as high ambient temperature or supply voltage above normal.

Do you think Genelec put her speakers in an oven?

 

[solderdude]

Chances are Genelec does test in climate chambers (not an oven) where one can control humidity and temperature.

 

[Frgirard]

Chances are Genelec does test in climate chambers (not an oven) where one can control humidity and temperature.

I don't found links about the climate chamber used by Genelec.
Have you links?
Thanks

 

[mansr]

Manufacturers don't typically publish their full test protocol. That doesn't mean they don't test things.

 

[Frgirard]

Manufacturers don't typically publish their full test protocol. That doesn't mean they don't test things.

You shouldn't take me for a pigeon.

 

[krabapple]

You shouldn't take me for a pigeon.

He's right. Good manufacturers do test their production runs and rarely if ever publish such tests. Does that make you a pigeon?