Misleading Measurements

[The Computer Audiophile]

Hey Paul, I just went outside to feed the chickens and step away from this discussion a bit. I then realized that I’d much rather have this discussion with you over a beverage at a local pub or something. It’s hard to remain cogent on a forum, interrupted by life, then other stuff, then posting, etc... You’re a very logical guy who I’m sure I’d love to talk to in person. Sure we have differences but that can be the fun part. 

 

I’m sure we could’ve gotten much further and possibly enjoyed the discussion. Such is online life. 
 

Enjoy your Sunday. 

[Summit]

32 minutes ago, pkane2001 said:

 

There's a reason for that, and we both know it.

 

 

Why yes, I've looked at audiophile switch measurements, at least those I could find. And found them to be well below audibility, in fact, below any measurement capability. This is as I'd have expected based on my understanding of networks. I've done a lot of testing and measurements in my own system, using different routers, switches, wi-fi networks, usb converters, optical networks, etc. I found no measurable differences (not just audible differences) that could be attributed to network equipment. 

 

As explained before, I prefer well-engineered products that improve transparency, even when I can't hear it. Audiophile switches do nothing to improve transparency of the system, cost a lot more, some generate a lot of heat and lower network speed. So, explain to me why I should be looking at one again? None of this sounds like good engineering.

 

And yes, measurements helped confirm all of this, so I'm still in favor of having them published for everyone to see and not hidden, as you seem to want, because someone might get the wrong impression. At the very least, the measurements confirm that the switch isn't causing harm to audio and that's already useful information.

 

Paul I’m curious, which source, DAC, amp and speaker do you have?  

[plissken]

41 minutes ago, The Computer Audiophile said:

Hey Paul, I just went outside to feed the chickens

 

You must be Bizarro to my Superman. Both drink tea and have chickens. Or it could be the other way around.

[The Computer Audiophile]

4 minutes ago, plissken said:

 

You must be Bizarro to my Superman. Both drink tea and have chickens. Or it could be the other way around.

Ha!

[plissken]

5 hours ago, Summit said:

Global Negative feedback even if they have clearly lower THD sound better that than apparatus with Zero Global Negative feedback.

 

I think Bruno Putzeys just did a really good article on feedback:

 

https://www.audioholics.com/audio-amplifier/amplifier-negative-feedback

[pkane2001]

44 minutes ago, Summit said:

 

Paul I’m curious, which source, DAC, amp and speaker do you have?  

This forum isn’t big enough for me to describe all my equipment

 

Three systems (one is 5.1) plus a ton of DACs audio interfaces, headamps, amps, headphones.
 

WiFi, Ethernet and USB are all in the digital audio path between the three floors. No PC in the main listening room.

[Clockmeister]

I can see this topic is quite a hot one at the moment.

Measurements will help you when designing products in certain areas, other measurements are essential for CE and UL certification.

Together with relevant  experience, empirical evidence and and understanding of what you are attempting to achieve all  go towards the attaining the end result.

 

I feel to much emphasis in audio  is paced on thd / sinad, yes these are important pointers, however recently a clutch of so called super dac's that are currently being touted as the best measuring ever, do leave a bit to be desired in the sonic replay stakes.

 

One of these much praised devices may have looked good in the sub 20Khz arena on an APx555 but in the real world the sound was very forward, grainy and stark plus two dimensional at best.

 

When looking deeper in to this particular product believe it or not there was NO line filtration on the a/c input side (CE anyone?) that was causing  high amplitude harmonic noise ingress way, way beyond even the fifth upper audio replay harmonic (100Khz).

 

There were other issues with this product yet potential customers were being swayed in that particular direction by a certain internet body. Audiophile parts being promoted as the desirable must and 'in' capacitors to be included at all costs. These were qucikly substituted for a far more suitable component for that particular application.

 

 

Now when designing digital audio products and power supplies a broad spectrum of methods should be employed to bring the design to fruition, common sense and understanding should be at the forefront of the initial concepts.

 

With all forms of power supplies measurements are very critical to achieving, satisfactory line stage common mode noise reduction, reduced switching noise, gate frequency optimization, PSRR  improvements. 

 

Recently I read an article where a European audio manufacturer claimed a noise figure of 2nv for an after-market power supply,  Needed a new kidney after rolling around on the floor for 20 minutes after reading that piece of marketing BS

 

Let me think:- "I know lets use the lowest possible available voltage reference and regulator the LT3045 assemble a nice transformer, cute looking enclosure, couple of fancy connectors and hey we have an ultra, ultra low noise supply 🤣

 

Here is a novel idea, measurements should be quoted at the point of entry and USE of the DUT (Dac/router/streamers/clock etc) while under  normal operating conditions for that DUT

 

My point here is measurements will assist you without a doubt, though you will need other attributes to finial your final design goal. 

 

 

 

 

[pkane2001]

23 minutes ago, Clockmeister said:

 

Here is a novel idea, measurements should be quoted at the point of entry and USE of the DUT (Dac/router/streamers/clock etc) while under  normal operating conditions for that DUT

I hope you meant at the exit and not the entry point. It doesn’t tell me anything about the DUT if the measurements are taken at the entry point.

[PeterSt]

5 minutes ago, pkane2001 said:

I hope you meant at the exit and not the entry point. It doesn’t tell me anything about the DUT if the measurements are taken at the entry point.

 

I am sure he meant that (entry point : where you hook up). And earlier on I wanted to say exactly the same, but I think I scratched that. So length of interlinks from DUT towards Analyzer and what the type of interlink is (quite meaningless to about everybody, but very meaningful to myself).

If I measure jitter, do I measure the clock in there, or at the output of the DAC (and at the end of interlinks etc.).

[Clockmeister]

Indeed my point was at the point where the DUT actually uses the power after all the psu transmission lines and circuit board entry, so what you are seeing is a real world noise figure at the point of use. The DUT has already been characterised thoroughly so you can de-embed all of the transmission lines, fixtures and interconnects before arriving at the REAL WORLD figures.

 

A combination of power analysers, Lecroy  12 bits scopes also time domain reflectometry with de embedding capability will help no end find the audiophoolery from the real mcoy. Clocks ultimately a phase noise measurement device like holtzworth with tell you more than any audio analyser.

 

Sorry for the confsuion

 

 

 

 

[Bill Brown]

I read this thread at the beginning then stopped for a bit, catching up on the last 3 pages or so today.  I began thinking of some historical context.

 

In the very old days, mid-late 50's to the 60's as "Hi-Fi" blossomed, measurements came to rule supreme.  Some realized there wasn't full correlation of the measurements with sound quality and shifted towards a more subjective approach (JGH, who did do some basic measurements), HP, purely subjective, and the reviewers they published.

 

Then was then the phase of Stereo Review and Audio magazines.  In these measurements were dominant and we were told that products that measured well couldn't be differentiated in listening (and note the measuring systems were comparatively crude compared to what can be done today).  I do have to note the loudspeaker measurer at Audio who developed the TEF measurement system that advanced the art significantly, Richard C. Heyser.  This dedicated piece of test equipment could perform the array of time-energy-frequency (TEF) measurements based on his pioneering work on time delay spectrometry (TDS) for audio, perhaps the next major advance after the development of the Thiele-Small parameters.

 

This is the era that I entered the hobby, first with subscriptions to the above two, poring over the measurements and dreaming and buying equipment based on their data.  Then I was exposed to Stereophile and TAS and my evolution took off.  Before anyone decries these, please remember that they were the only sources available to us (aside from coming and going fringe sources).  Was this a normal/natural progression?  I think it was for me.  Surely it wasn't for all.  That is probably ok.  I suspect those folks are analogous to the current ASR types.

 

When JA became the editor at Stereophile it was very important to him to institute a measurement program with the stated intention of attempting to develop a body of measurements that would correlate with listening impressions.  He has expressed disappointment that this hasn't been as fruitful as he would like.  Certainly there remain massive questions/gaps in understanding, but there have been some good things.  The hypothesis of, then measurement of jitter (unknown as an issue in early digital products) would be one, further advances in loudspeaker measurement another.  I do think at this point that I am able to interpret to at least some degree correlation of subjective impressions with measurements.  It is certainly worthwhile to see measurements of products that seem poorly engineered in very basic aspects.

 

I drifted away from TAS at that point as I wished for measurements, believing that there would likely be measurements that correlated with the reviewers' subjective impressions, perhaps producing euphony (emphases in certain speaker frequencies, 2nd harmonic distortion, etc. as examples).

 

I am neither a radical subjectivist or objectivist.  I want to read both, and do.  Engineering advances guided by measurements are important.  Listening is important as I don't think measurements fully correlate with listening.  Too strong an emphasis on either isn't as interesting to me.  I occasionally skim through ASR just to see the measurements, but avoid the commentary, have no interest in the attitude, and don't have the site bookmarked by any stretch.

 

It is just a hobby.  There will always be all types, some that evolve in different directions, some that don't, oh well.  No need to fight about it.  I suppose in this respect, I disagree with your fundamental hypothesis, @The Computer Audiophile, just let them have their fun. 

 

Bill

[The Computer Audiophile]

25 minutes ago, Bill Brown said:

I disagree with your fundamental hypothesis, @The Computer Audiophile, just let them have their fun. 

I enjoy your disagreement. Thanks for posting. 
 

Now I’m going on vacation (unrelated to this discussion). To Ely, MN for the week :~)

[AudioDoctor]

1 hour ago, The Computer Audiophile said:

I enjoy your disagreement. Thanks for posting. 
 

Now I’m going on vacation (unrelated to this discussion). To Ely, MN for the week :~)

 

Safe travels and remember, if you see a bear grab the nearest fresh steak and run!

[Confused]

11 minutes ago, AudioDoctor said:

 

Safe travels and remember, if you see a bear grab the nearest fresh steak and run!

Yes, and never pause to measure it before running.

[ShawnC]

2 hours ago, The Computer Audiophile said:

 

Now I’m going on vacation (unrelated to this discussion). To Ely, MN for the week :~)

Are you going to the Soudan Underground Mine and looking for Neutrinos?  I tried to catch a WIMP but it went right through me😉

[AudioDoctor]

Don't forget the Hockey Hall of Fame in Eveleth either Chris.

 

It's allegedly #1 of all 5 things to do in Eveleth MN...

 

https://www.tripadvisor.com/Attraction_Review-g43055-d123097-Reviews-U_S_Hockey_Hall_of_Fame-Eveleth_Minnesota.html

[fas42]

For some bizarre reason the concept of weighting barely registers in the audio world - in many fields this is a vital component for assessing the relative importance of various factors; a brilliant number in some area is almost irrelevant, because it has a low weighting in the overall. But audio is caught up in the 'purity' of specific numbers, in themselves - no wonder people have no idea how good some component will sound; when starting from this low base in measuring technique.

[fas42]

6 hours ago, pkane2001 said:

This forum isn’t big enough for me to describe all my equipment

 

Three systems (one is 5.1) plus a ton of DACs audio interfaces, headamps, amps, headphones.
 

WiFi, Ethernet and USB are all in the digital audio path between the three floors. No PC in the main listening room.

 

Which tells me a thing or two ... 😁.

 

First thing I would do if I visited you to listen, seriously, to your "best rig", would be to go throughout your home, and pull the plug out on every single item that wasn't actually needed to make that primary rig work - and see what that gave me ... that would give me a baseline for assessing what the potential in SQ was, 🙂.

[pkane2001]

13 minutes ago, fas42 said:

 

Which tells me a thing or two ... 😁.

 

First thing I would do if I visited you to listen, seriously, to your "best rig", would be to go throughout your home, and pull the plug out on every single item that wasn't actually needed to make that primary rig work - and see what that gave me ... that would give me a baseline for assessing what the potential in SQ was, 🙂.

I’m afraid that’s quite impossible. All the plugs are removed and the bare wire soldered in. It cannot be pulled out... you know... to improve SQ

 

[fas42]

2 minutes ago, pkane2001 said:

I’m afraid that’s quite impossible. All the plugs are removed and the bare wire soldered in. It cannot be pulled out... you know... to improve SQ

 

 

... you do have those panzerholz headvices concreted in place, to guarantee the perfect alignment of the ear canals to the sound waves, of course ... ?

[pkane2001]

1 minute ago, fas42 said:

 

... you do have those panzerholz headvices concreted in place, to guarantee the perfect alignment of the ear canals to the sound waves, of course ... ?

Of course! Made out of the best balsa wood, naturally.

[Audiophile Neuroscience]

7 hours ago, Bill Brown said:

just let them have their fun. 

 

But Bill, they need to be saved from themselves !🤣🙄

[Audiophile Neuroscience]

12 hours ago, The Computer Audiophile said:

If you’re going to argue for things that don’t matter, why stop anywhere. Let’s include the color of the DAC in the measurements. It has a much to do with the sound quality as a measurement that doesn’t impact the DAC’s performance to human ears. 

 

Yellow and Red Dacs have a warmer tone, blue and white a cooler sound coloration. I think this is the main reason Toole advocated blind testing😄

[sandyk]

50 minutes ago, Audiophile Neuroscience said:

 

Yellow and Red Dacs have a warmer tone, blue and white a cooler sound coloration. I think this is the main reason Toole advocated blind testing😄

 The problem here is that we are relying on Subjective reports by the suppliers and Reviewers, as well as Measurements which may or may not, be applicable , or even enough parameters measured, or for that matter, even  representative of a product due to the variance between production samples.. Perhaps even a "blue printed" or carefully selected sample supplied for reviews in some instances ? 

 I would hope that the vast majority of this forum's members are smart enough to do their comparisons "non sighted, with all components powered up as to give no hint as to which device is currently being used.

 This is certainly the way that sessions where David and myself  have been present are performed.

[Teresa]

14 hours ago, pkane2001 said:

This forum isn’t big enough for me to describe all my equipment

 

Three systems (one is 5.1) plus a ton of DACs audio interfaces, headamps, amps, headphones.
 

WiFi, Ethernet and USB are all in the digital audio path between the three floors. No PC in the main listening room.

 

WOW! Tons of equipment on three floors! You must be a millionaire.

 

We need a WOW button.