Nearly all manufacturers do not advertise/exhibit their product measurements? Why?


After my Audio Science Review review forum, it became apparent that nearly the only way one can determine the measurements of an audio product is wait for a review on line or in a publication.  Most equipment is never reviewed or is given a subjective analysis rather than a measurement oriented review.  One would think that manufacturers used tests and measurements to design and construct their products. 

Manufacturers routinely give the performance characteristics of their products as Specifications.  Those are not test measurements.

I searched the Revel speaker site for measurements of any of their speakers and could not find any.  Revels are universally lauded for their exceptional reviewed measurements.  Lack of published manufacturer measurements is true for nearly every speaker manufacturer I've searched for on line, perhaps several hundred.   Same is true for amps, pre-amps, DACs, transports, turntables, well you get the picture.  Do they have something to hide?   I doubt the good quality products have anything to hide but poor quality products do.  

ASR prides itself in providing "true" measurements that will aid in purchase decisions.   Why don't the manufacturers provide these measurements so that reviewers can test if they are truthful or not?

Then there are the cables and tweaks for which I suspect that there are inadequate tests available to measure sonically perceived differences but which objectivists believe don't exist or are "snake oil."  

Well, please chime in if you have some illuminating thoughts on the subject.   

I would have loved to see manufacturers measurements on my equipment and especially those that I rejected.  

fleschler

@fleschler 

"As to tweaks, I say try it and if you like the sound results, keep it. "

Excellent advice.  I would just make sure you only use your ears in such an evaluation.  They are trivial to test this way because they don't change any linear aspects of the device (levels, frequency response, etc.).  Have a loved one add or not add the tweak 10 times and see if you can tell the difference 8 out of 10 times.  Take all the time you need.  Let your ears and only your ears be the judge and not fall for statistical error.

If you do pass such a test, repeat with capturing a video of it and we have something wonderful to discuss!  If you can't do that, then measurements, null tests, engineering analysis of what is going on, etc. are great help in getting to truth of the matter.

@amir_asr

If you do pass such a test, repeat with capturing a video of it and we have something wonderful to discuss! If you can’t do that, then measurements, null tests, engineering analysis of what is going on, etc. are great help in getting to truth of the matter.

Don’t just show up here and start telling everyone what to do when you don’t lead by example. You have not posted your own system, pics and measurements in the virtual system page, as you say, "we will have something wonderful to discuss"
You are all about what the OP should do, let’s go and show him what you got, you gonna walk or talk? I promise to make no disparaging remarks, just try to be helpful, please do same.

Is anyone beside me surprised that someone who is an expert on measurements either doesn't have or won't post his own room with his own measurements in the virtual system area, in a thread on measurements????

 

 

@holmz

I felt there is no other way for you to get the info you were requesting about gear.

The measurements of the gear are different than the measurements of how the gear behaves in a room right?

That depends on if it is a signal measurement or a room measurement?
The former is an electrical thing for components, IC, speaker cables, amps.
The later is about fields, which are measurement of the resulting acoustic field… that combines the electrical signal with the speaker and the room.

To isolate and remove the room and speakers, makes it a bit easier to consider how each component, IC, cable etc is contributing or not to the overall picture.

The ICs will not really have a whole lot to do with the room, unless it is high inductance or capacitance and being use like a tone control.

If there is some other thing happening with crystal boundaries, or dielectric polarisation, then that too should show up as the signal being changed when comparing one IC with another.
When this cannot be shown, it leads me to believe that it may not be measurable.

 

I advocate getting the room right first and yes, in room measurements can indeed make the trial and error process a bit faster (and maybe even less expensive).

^This^ I can abide.

 

Now, to answer your question to the OP of how to separate the real deal from a fable I can’t tell you a single measurement that will get you 100% guaranteed satisfaction that your money was a good investment. If you know a better way than auditioning it in your own room I am open to trying it.

Well there is a null test, and ICs should respond well to that… and power cords should show that the signal coming out of say a power amp is either the same or changed if one can compare them. But this never seems to be shown. 

Speaker cables have inductance and capacitance, and the speakers have larger current demands than an IC. When a cable coma-any has specs that is great.
With, or without, that I can only assume that if I want the total inductance and capacitance to be low, then I should probably keep those cables on the short side.

I’ll likely stay with the IC mostly using Mogami/Neutrik  combo, and a few speaker cables of Magomi or cotton/.copper, and a few ICs using silver and cotton.

Most of my ICs are only as long as they need to be, and I would rather spend the money on electronics until such time as I can understand if the IC are different or not.
Better is good, but to begin with can we even know if they are different? 

 

I would not recommend just taking some expensive speakers that measure well and sticking them in a room with bare walls like some of our scientifically minded guests.

There are step function and impulse response measurements.
The FR can be largely corrected with DSP/EQ, and the impulse response somewhat corrected with Dirac.

Whether someone starts off with the room or speakers, they often often end up with both good speakers and a somewhat treated room.  More often than not the room work comes later… so there is no great dishonour in having speakers that measure better as a start.

It doesn’t matter too much how well treated a room is treated if the speakers have poor impulse response, poor frequency response, resonating boxes, being output limited by compression, and have high harmonic (IM, and Doppler) distortion… but the room treatment may help with their radiation pattern and remove some brightness from the FR.

 

For casual listening, fine. For critical listening and professional reviews maybe get some feedback from a knowledgeable third party like Anthony Grimani at www.sonitususa.com or Jeff Hedback at www.hdacosutics.net.

A lot of people start with a speaker in a room, and then go to DSP, Dirac, or RoomPerfect, and/or add treatments.

I guess this last part is what separates us?
Namely whether it is a for critical listening, or causally listening to music.
And then what are we critically listening for?

I often start out wanting to listen to music and get blocked by sibilance, and once the grating sibilance is gone, then I get happy again.
The recordings that are overly sibilant just end up staying in their sleeves most of the time.

Quick post answer (I haven’t read them all yet). @holmz

1. I didn’t know that he needed a new power cord but upon seeing what he was using, knowing friends negative experience and knowing my own experience with this particular high end cable, I suggested it. He didn’t believe in it as an electrical engineer but did a 180 after he heard it for himself.

2. As to the ragged frequency response so obvious in the bass, I had two friends accompany me pre-power cable change and the Golden Ear remastering engineer friend blurted out that it sounds terrible. He is high functioning slight autistic so he just let loose. We heard as well but didn’t know why with such great gear. Anyone could hear that the bass was not linear, but ragged going up and down the scale. It was a total mess.

You write like a know it all as well. Why don’t you take a leaf from the book of ASR member Matt Hooper/prof (here) and read his comments on subjective listening and opinion (even as posted on ASR). The link is on page 3 with his agreement with Audiogon members (eventually) at the bottom third of the page.