About hearing something and measurements, I'm convinced the ear can measure a lot of things equipment can't and the body feels what the ear can't, it's a fact.

The audiophile industry couldn't exist without you.....

 

My long career was as an engineer in the high performance audio industry.
I have been an audiophile all my life. But I am not an an audiophool.

The audiophools bought extremely expensive Monster Cable.
I used ordinary inexpensive lamp cord that worked exactly the same.

The audiophools bought extremely expensive amplifiers with vacuum tubes glowing on top. The vacuum tubes were for show since they were not connected to the circuit of the amplifier.
I made and bought inexpensive excellent solid state amplifiers.

The audiophools bought extremely expensive speakers that looked good and sounded good. I listened to the expensive ones but bought inexpensive speakers that sounded the same and they did not look bad. I made many inexpensive speakers that have excellent sound.

The audiophools made up adjectives that described phantom types of sounds. If they were given a "blind" test of products then their selection was purely random and was different each time the test was given to them.

 

The audiophools made up adjectives that described phantom types of sounds.

My favorites:

"It has a more "natural" sound......"

"It has better "presence"...."

"It has superior "definition"...."

I'm sure I have forgotten a lot more

 

I used ordinary inexpensive lamp cord that worked exactly the same.

I made and bought inexpensive excellent solid state amplifiers.

I made many inexpensive speakers that have excellent sound.

If you don't understand that the body (skin, bones,..) can hear the music throught vibrations it's not my fault.

Ok, so can you suggest me some high-end gear in each category at inexpensive price which sounds the same?
Since you have so many types in mind why don't you share with us?

I've just received the answer from SPL that they choose the TL071 just because they like its sound better, not for cost reason, their alternative chip is the OPA134 but they feel during listening sessions that it sounds a little bright in some recordings.
I don't understand why if the chips are all identical the producer feels one chip better sounding than another.

 

When the word "bright" is applied to sound then it is with a boost or distortion in the upper midrange and higher frequencies.

I recently read that some FM radio stations add a fairly high amount of distortion to high audio frequencies to make the sound "bright".

The OPA134 does not boost high frequencies and its distortion is extremely low so I don't understand how it can sound "bright".

A while ago I bought some crossover coils at a local high priced Name Brand speaker manufacturer but their inductance was wrong. The expensive speakers that used them also sounded wrong. I measured the frequency response of the speaker and it was not good. But they made many speakers like that and they and their customers thought they sounded fine.

 

they chose the TL071 just because they like its sound better, not for cost reason, their alternative chip is the OPA134 but they feel during listening sessions that it sounds a little bright in some recordings.

I don't understand why if the chips are all identical the producer feels one chip better sounding than another.

I understand it. People hear what they believe they hear.

John has participated in a large number of blind tests over the past 28 years, and has discovered that it is "extraordinarily hard to produce anything but a statistically null result." ////


Arny strongly emphasized that sighted listening as practiced by magazine and webzine reviewers fundamentally changes the listener's mental state and is therefore unreliable as a means of assessing sound quality.

http://www.stereophile.com/news/050905debate/

 

If you don't understand that the body (skin, bones,..) can hear the music throught vibrations it's not my fault.

Really. Do you understand that most sound below about 50 Hz is "heard" in the human body via bone conduction?

I suspect AG understand the audio subject very well. What you posted doesn't affect what he has been saying. There is absolutely no audible difference between the parts listed in a pre amp application. One producer's opinion is hardly a base on which to build the science of acoustics.

 

Thank you all for sharing your point of view.

I'm right in the middle of the only sound vs only measurements matter.

Maybe I'm influenced a lot by reading reviews, but I'm also influenced by reading people who think cables don't influence sound.
My brain tells me each cable do influence sound and of course that's because each cable has its electrical characteristics.

I'll test the op-amps just for fun and I will post my results in the following days, I feel more influenced now by the technicians who are sure I can't hear a difference, but I'm still curious.

 

Install a socket in the board so you can plug in either op amp.

have your friend alternately turn the unit off and plug in one or the other op amp at random (blind to you) with device chosen by coin flip. You listen as much as you want and then you record "better or worse" for each case. Use the same music and headphones. Do that comparison maybe 25 times or more and at the end compare your results to his list and see if the "bad" one sounded bad a significantly larger percentage of the times you chose.

 

It is unlikely but you might have a defective opamp.

I designed and had an audio equalizer built with TL074 quad opamps. Over 10,000 were built and sold and not one was returned. After assembly each one was tested for 0.05% distortion or less, -70dB signal to noise level, accurate filter frequencies and low supply current.

Only 2 failed the test: one had the opamp IC installed backwards and the other had a shorted power supply filter capacitor.

Today I read a few articles about the sound of different opamps. One said that OPA134 opamps sounded harsh and another said the opposite that they sounded "layed back".
Who can you believe?

 

On the good audio at a good price question...

Back in the day Bryston made very, very good amplifiers at great prices. When Film House took over Mirrophonic sound (two motion picture post-production studios in Toronto) back in the late '70s we replaced all our McCurdy and Mcintosh tube amplifiers with them. They were top notch. Measured performance blew the old tube amplifiers out of the water and they did actually sound better too. They were tough as well, standing up without failure to the rigors of professional studio abuse. Zero maintenance required.

However, the audiophiles got a hold of them. Now the company makes vastly over-spec'd products with enormous prices.

On the cable question, if the impedance of the cable is small when compared to the speaker over the desired range of operation and is capable of handling the current flow, it will be fine. It does not matter how the strands are wound, or what the insulators are made of. The only way this is not true is if our understanding of physics is incorrect.

For instance, #16 lamp cord should be able to handle in the range of 3000 watts into 8ohms over 10 feet (that would be about 0.04 ohms for the cable. A 200:1 ratio) without any issue at all. So if your are buying #6 cable for your 200 watt amplifier you are whacked.

Here is an excerpt from a Monster Cable ad:

"For serious audio enthusiasts, ultimate performance speaker cable can make a great system sound even better. Featuring patented Monster technologies including 2-way Time Correct® windings, XLN® Xtreme noise rejection construction and PEX™ dielectric, Monster Performance Speaker Cables deliver intense audio with maximum sonic clarity. Highs are extended and open. Midrange takes on a dimensionality that brings you closer to the experience. And low frequencies become tighter and more dynamic for sound reproduction so faithful you’ll swear it’s the original source recording."

​

My years in the audio industry and my background in physics tells me 2 things about this:

1. It's total bunk
2. PT Barnum was right, there's a sucker born every minute.

 

My years in the audio industry and my background in physics tells me 2 things about this:

1. It's total bunk
2. PT Barnum was right, there's a sucker born every minute.

You would be surprised what a large segment of the world economy depends on them.....

 

It's so sad, isn't it?

 

It's so sad, isn't it?

As all the kids say these days:

It is what it is.....

 

You can't hear the noise generated by the TL071 (even with headphones) because it is something like 80 - 90 dB down from the signal levels that a pre amp is operating at. The standard "line levels" in stereo (which are pre amp output levels to the power amp) are 0.775 VRMS = +3dB. That puts the 0 dB pre amp level at about 0.55 VRMS. When I did the noise calcs for my pre amp design, I used the higher noise FET amp LF-356 and the noise from it was still about 75 dB down. Even using Sennheiser headphones, the "hiss" is completely inaudible.

 

Hi Bountyhunter,
I also cannot hear noise that is at -90dB. I also can't hear distortion that is at -90dB (0.003%). Can you hear it?

Can anybody hear it? Maybe my dog can hear it.

 

Hi Bountyhunter,
I also cannot hear noise that is at -90dB. I also can't hear distortion that is at -90dB (0.003%). Can you hear it?

Can anybody hear it? Maybe my dog can hear it.

Nope. I always avoid distortion discussions because usually somebody is telling me they can hear .05% distortion never realizing most loudspeakers impart distortion in the 0.5 - 1% range to the sound or worse in the case of woofers.

I don't know what people think they hear, but I know that the MP3 "conversion" bends the music pretty badly each time you edit a file and resave it as an MP3. I could hear "warbling" on some MP3 files saved only a few times, so I stopped using MP3 to edit and worked only in WAV files until I was sure I had it edited, equalized and cleaned up completely then I convert it to MP3 at the highest quality level (320 k/B) and they sound good to me. But a lot of people I have heard say they can hear the difference in MP3 files and I believe they might (?).

 

A poor quality MP3 uses a low sample rate that beats against the high audio frequencies and causes audible "warbling". People who make low sample rate MP3s should be hanged and shot.

 

A poor quality MP3 uses a low sample rate that beats against the high audio frequencies and causes audible "warbling". People who make low sample rate MP3s should be hanged and shot.

Yeah.


I miss the "old days" where I bought CDs with WAV files on them....... now I buy MP4 files from Itunes and have to rip them onto a CD in WAV format to strip off the copy protection from the file, then rip them back onto my PC so I can use the files....

 

After nearly two months testing and swapping opamps I'm convinced they make a good level of sound difference in my system even if theorically I can't hear such a low noise, distortion and such measurables differences.

In a blid test I'm able now to pick clearly which of the 3 opamp are installed in my SPL Volume 2 preamp (which has dip8 sockets so it's easy swapping). I've tested a lot with fast swapping and in long listening session for few hours or few days, I think now I'm able to conclude something or at least my brain and body is convinced so, that's what's really important.

To summarize and without beeing too audiophile...
TL071 has the lower sound quality, with a dry and compressed presentation, lacks details and dynamics.
OPA134 is easier to listen but it's on the dark side and I miss some high freq details and dynamic, bass is also not very well articulated.
The TLE2071 is clearly the best with better dynamic and details, still musical and natural, with bass which is more articulated. I can hear more of anything with the TLE2071.

So I prefer not the more expensive, neither the best specs on paper, I'm convinced by the sound only. Maybe the TLE2071 being a direct replacement from the same company is still the best synergy in my preamp.

For reference I list my main system which reflects my taste for natural acoustic sounds (I'm a sax player) and it's not a budget oriented system, neither each piece is the most expensive I could buy it's just what I think was/is best money/performance:
Yamaha NP-S2000 network streaming player at around Euro 1.400 preferred over more expensive components tested like Linn Akurate DS newest version or Resolution Audio Cantata at around Euro 5.500.
SPL Volume 2 at around Euro 400 with TLE2071 no need to buy more expensive components like Electrocompaniet EC 4.8 at around Euro 4.000.
Electrocompaniet AW 2x120-M power amp at around Euro 5.000 preferred over Bryston and others at nearly the same price.
Trenner & Friedl Pharoah speakers at around Euro 8.000 preferred over any brand at any price...

I'm very happy I've tested a few different opamps, with the TLE2071 I've upgraded the SPL Volume 2 up to a point I don't feel the need to buy a much more expensive preamp.