The “Sound” of receivers…

[b_panther_g]

Hey guys,


Has anyone ever done a DB comparison of mid-fi receivers? If all the models tested had pre-outs, were all connected to the same amp, and they were all adjusted to the same volume – can/did anyone here the difference in a DBT or a SBT?

If it’s never been done before, would the Audioholics be willing to perform such a shootout?

As a control, I guess they could use uncompressed .wav files from a computer and a quality sound card with analog outs. This would allow them to connect the computer directly to the amp and still control the volume.

Does anyone else have any thoughts about this? Does it sound like a good idea? Is such a test even possible? Or maybe I’m the only one who would like to know.

Anyway, just a thought.

Later,
B

 

[ruadmaa]

Sound of Receivers

Tests have been conducted before by such magazines as Stereo Review (Hirsch Houck Labs). Their conclusion after carefully controlled tests was quite simple - all receivers sound the same. You'll hear quite a bit of squawking about that statement on this forum but no one to date has ever been able tell a Sony from a Denon or Pioneer or any other receiver you care to mention for that matter (under highly controlled double blind testing).

Argue all you want to people, I personally have never heard any vast difference in any receiver I have ever owned since the 1960's. If you think a certain receiver sounds better, simply buy it. Myself, I would put my faith in the research done by Julian Hirsch.

 

[Karp]

If the receivers had exactly the same bandwidth, THD, DAC's, and exactly the same power there wouldn't be a difference. They don't though, and I can hear a difference between brands. Most of the time I cannot tell the difference between two models of the same brand, although I have never compared a cheap model vs a flagship model of the same brand. I am quite sure there would be a easily noticed difference between them.

If you compare three different receivers with the same "rated" power you definitely hear a difference, since they do not all have the same amount of power or bandwidth.

I brought a meter with me when I was shopping for receivers to make sure that they were at the same db level, and set the three receivers in Pure Direct mode. I listened to the same set of speakers for all three. I brought my own CD's with me. I listened to a Dennon, Yamaha, and Pioneer Elite and preferred the Dennon - It sounded warmer and had more punch in the bass region that the other two. The Yamaha sounded accurate but a little flat. The Pioneer sounded a little bright.

I had a friend with me and had him switch between the three randomly without me looking and I could pick out the Dennon every time, and could tell the difference between the Yamaha and the Pioneer most of the time.

I certainly do not have "magic" ears, but I could tell a difference.

I could also hear a difference between a HK, Onkyo and Sony when I was at CC, although I didn't listen to them "blind".

Just my 2 bits.

 

[Rob Babcock]

Without making any judgements upon the topic, it would be fair to point out that the Hirsch/Houck Labs experiment was done over twenty years ago (maybe much longer- I remember reading the article in my HS library! I graduated in the 80's...). I certainly don't recall any Denons in the test, and if memory serves, the only receivers were an Onk, a Yammie & a Pioneer. I could be wrong about the specifics, but not the date. This test was done well before the advent of affordable digital (eg mass success of CDs) and DSP, too. This doesn't invalidate the test- and it was amusing to see the test reveal no diff between a spendy OTL tube amp and a cheap Pioneer receiver. But I'm not aware of any recently done test.

One other note: much more recently (say, within the last 7-8 years) the same mag (now called Sound & Vision) conducted a series of tests with musicians, and in the one of these tests the members of one band (was is PHish?) easily and reliably differentiated between a tube & SS amp. Was the test done properly? If not, then I'd also have to wonder about the first test they did. Food for thought.

 

[mtrycrafts]

Without making any judgements upon the topic, it would be fair to point out that the Hirsch/Houck Labs experiment was done over twenty years ago (maybe much longer- I remember reading the article in my HS library! I graduated in the 80's...). I certainly don't recall any Denons in the test, and if memory serves, the only receivers were an Onk, a Yammie & a Pioneer. I could be wrong about the specifics, but not the date. This test was done well before the advent of affordable digital (eg mass success of CDs) and DSP, too. This doesn't invalidate the test- and it was amusing to see the test reveal no diff between a spendy OTL tube amp and a cheap Pioneer receiver. But I'm not aware of any recently done test.

One other note: much more recently (say, within the last 7-8 years) the same mag (now called Sound & Vision) conducted a series of tests with musicians, and in the one of these tests the members of one band (was is PHish?) easily and reliably differentiated between a tube & SS amp. Was the test done properly? If not, then I'd also have to wonder about the first test they did. Food for thought.

You wouldn't have a good citation to that recent tes 7-8 years ago, would you? I do have a pretty good collection of published tests I may have that too.
In 1990 at the 8th Internationla convention of AES in their papers, they reviewed 23 previous DBT amp tests going back to the 1977 and on. 13,000+ trials. One amp was different, 10 watts compared to a 400 watt amp.
Some other significant outcomes had technical reasons, hence not really significant.

In the Spring 1997 issue of The audio Critic, Tom Nousaine reported on a test of Steve Zipser of Miami, Sunshine Audio, and two others. Yam AX-700, 100 watt integrated amp and Pass Lab Aleph 1.2, $14k, all three persons were null results.

The Audio Critic has been auditioning components over most of their existance, certainly after Peter Aczel gave up his golden ear certificates
While no exact numbers I know about, the components are transparent. The Technical Editor, Dr David Rich presented a paper on this to AES:
"Topological Analysis of Consumer Audio Electronics: Another Approach to Show that MOdern Audio Electronics are Acoustically Transparent", Rich, David and Aczel, Peter, 99 AES Convention, 1995, Print #4053.

While these components are not from last years crop or todays, why would they be worse than the older ones? Certainly our hearing is not evolving to better resolve smaller differences

The $ensibe $ound, issue 74, Apr/May 1999 did a CD player DBT, $80 RCA RP 8065 against ones costing $1000s, no names given , with nul results.
So, if that cheap player is sonically the same, one would have to design on purpose to be euphonic that, I guess, some will prefer.

 

[Rob Babcock]

Wish I could remember which issue...I have a couple of large tuperware-type totes of old audio rags, maybe I kept it. I was a bit skeptical at the time, but I didn't have any overt reason to think they failed to control the tests properly.

I don't know if the new electronics would necessarily be better. They may be better or simply cheaper & more profitable for the manufacturers. Nor do I know how the tests you allude to were conducted, or if they were conducted properly or with decent equipment. I'm only pointing out that in the newer S&V tests, there were verifiable, repeatable correct IDs well out of proportion to chance. That's S&Vs conclusion, not mine.

 

[Rip Van Woofer]

...in the one of these tests the members of one band (was is PHish?) easily and reliably differentiated between a tube & SS amp. Was the test done properly?...

A tube vs. SS amp is likely to be an "apples and oranges" comparison of course, as many tube amps have distinct sonic coloration, generally caused by high second harmonic (?) THD. High output impedance (resulting in a low damping factor) and frequency response irregularities are also "features" of some tube amps that are undeniably audible.

Otherwise: when the (figurative) blindfolds are on and the levels are matched, no one - NO ONE - can reliably tell a low-end Pioneer from a Krell. All modern, well designed amps (and electronics in general) have performance that is sonically transparent, with distortion, noise, and frequency response abnormalities that are below the threshold of human hearing. Tube gear does not qualify as "modern". One would think we would simply rejoice and consider such a state of affairs a golden age (or at least save our concern for the things that are still imperfect, like speakers)...but lots of folks need a reason to believe otherwise, it seems.

Finally, it mystifies me that double-blind testing (a.k.a. ABX in the audio world) is unreservedly considered the "gold standard" for experimental evidence in every scientific discipline from the "hard" sciences like physics to "soft" fields like psychology - but that audio, an engineering discipline that is based on several scientific fields, is held to be an exception to this established scientific standard by so many otherwise sensible and presumably educated people.

 

[Rob Babcock]

I dunno, Rip. In Stereo Review's initial experiments, no one was able to distinguish tubes from SS, either. I don't recall what speakers & associated gear they used in their first test, but they did carefully level match.

The euphonic coloration of tube gear is often wildly overstated; sure, some of it measures badly, but a lot of it doesn't. Certainly there's mounds of evidence stating that the diff between .1% THD & .001 is totally inaudible with music, so even fairly large amounts can't account for the supposed difference.

I don't know the circumstances of the 2nd test, or whether or not their methodology was sound, but I do recall their conclusions. I'm not sure what they were hearing.

BTW, the 2nd test was also an ABX test.

 

[mtrycrafts]

Wish I could remember which issue...I have a couple of large tuperware-type totes of old audio rags, maybe I kept it. I was a bit skeptical at the time, but I didn't have any overt reason to think they failed to control the tests properly.

I don't know if the new electronics would necessarily be better. They may be better or simply cheaper & more profitable for the manufacturers. Nor do I know how the tests you allude to were conducted, or if they were conducted properly or with decent equipment. I'm only pointing out that in the newer S&V tests, there were verifiable, repeatable correct IDs well out of proportion to chance. That's S&Vs conclusion, not mine.

I am not questioning you on this, just wanted to collect that article to add to the library, and read it as well

 

[Rob Babcock]

I wish they had a database of old articles. Or maybe they do but you have to subscribe (doesn't Stereophile do this?). It does seem to run counter to other studies I've read, but if I can find it I'll let you know what issue it is. But it could take awhile- I'll have to do it "the low tech way", by digging thru back issues.

 

[mtrycrafts]

Finally, it mystifies me that double-blind testing (a.k.a. ABX in the audio world) is unreservedly considered the "gold standard" for experimental evidence in every scientific discipline from the "hard" sciences like physics to "soft" fields like psychology - but that audio, an engineering discipline that is based on several scientific fields, is held to be an exception to this established scientific standard by so many otherwise sensible and presumably educated people.

Well, not all of audioland this is true Hi end, certainly. Dr. Floyd Toole at Harman now but spent a lifetime at Canadian National Research Center
http://www.crc.ca/en/html/aas/home/evaluation/evaluation#recent_tests

still doing DBT research along with the speaker companies who participated there, Paradigm, PSB, Mirage, etc. Dunlavy did. There are some in audio, certainly not universal.
How would you sell products if there is not sonic differences?

 

[mtrycrafts]

Wish I could remember which issue...I have a couple of large tuperware-type totes of old audio rags, maybe I kept it. I was a bit skeptical at the time, but I didn't have any overt reason to think they failed to control the tests properly.

I don't know if the new electronics would necessarily be better. They may be better or simply cheaper & more profitable for the manufacturers. Nor do I know how the tests you allude to were conducted, or if they were conducted properly or with decent equipment. I'm only pointing out that in the newer S&V tests, there were verifiable, repeatable correct IDs well out of proportion to chance. That's S&Vs conclusion, not mine.

I found a link to the Steve Zipser test in Florida

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=501fl6$ac3@oxy.rust.net&rnum=1&prev=/groups?q=sunshine+stereo+yamaha+abx+nousaine&hl=en&lr=&ie=UTF-8&oe=UTF-8&selm=501fl6%24ac3%40oxy.rust.net&rnum=1

 

[cornelius]

I feel another locked thread coming on.

 

[Mudcat]

Okay, before this thread gets locked.

I do not have golden ears, I'd like to think my wife does. I got my switcher (one of those amp/speaker switches you see at places like Tweeters, so you can listen to one of several amps and one of twelve pair of speakers - got it off ebay), took my Yamaha RX-V1400 out of the rack and tested it along side my Yamaha 396 stereo, an old Onkyo 600 something or other 9FROM THE 80'S), and old Technics (from the early 80's), and a very old Lafeyette (one of those all encompassing stereos with cassette, eight track, and turntable built into a single box). Hooked everything into the switch (5 receivers into a single pair of speakers). All my wife had to do was disconnect and reconnect the CD player (Pioneer Elite DV45A) to whatever receiver she was going to play from.

She tested me and I could not tell which was which. I tested her, and she could pick out the Lafeyette. She said it sounded muddy. The speakers were Mirage Omni 7s. (Before we went blind, we did a visual listening too.)

Then using my SPL meter (Rat Shack thingamagiggy), I tested each one to 80 dB c weighted through the same speakers, and measured (while playing a 1000 hz tone from a test disk):
1.62 volts on Yamaha 1400
1.62 volts on the Yamaha 396
1.83 on the Onkyo
1.95 on the Technics
2.03 on the Lafayette

Conclusive? hardly, but I had fun doing it since it took about 3 hours and I got to use some dorment devices. I was actually surprised the Technices and Lafayette still worked as they'd been in the attic for several years.

 

[Rÿche 1]

Their conclusion after carefully controlled tests was quite simple - all receivers sound the same.

I beg to differ. I just replaced a Yamaha RX-V630 with a H/K DPR-1001, and i'm quite confident I could pick the H/K out in a blindfold test.

 

[mtrycrafts]

and i'm quite confident I could pick the H/K out in a blindfold test.

We won't know for sure untill this happens. Historically the odds are against you

 

[Rob Babcock]

To be totally fair, though, a negative result is only that- just a data point. A failure to distinguish in any given test only means the participants of that test can't hear a diff, not that there isn't one. I'd say to be statistically convincing you'd need a lot of subjects and/or a lot of tests.

I'm not saying they do sound the same or they don't. Despite a few studies and a lot of arguing, I've yet to see ironclad proof either way. How's that for hedging my bets?

 

[b_panther_g]

WOW. This thread really took off…

OK back to the topic at hand. Here’s my opinion FWIW…


I do believe that many people will be able to tell the difference between receivers ONLY IF they use each receiver’s internal amps. Why? Because I’m of the opinion that when amps approach their limits, they distort in different ways. The unique distortion of a receiver's amp would give that receiver a distinctive sonic signature.

(Please bear in mind…I do not think that amps have a sonic signature when they are not pushed beyond their “comfort zone.” I just believe that its very easy to push a typical 100W or even 200W amp to its limits with out even realizing it.)

Now if we take the receivers’ internal amps out of the equation, will the receivers still sound different? Well… I don’t know. I guess that there’s a difference in the sound of the DACs. But can the average (or even the above average) human hear it? Again, I don’t know. I’d sure like to find out though.

Later,
B

 

[b_panther_g]

Actually, I just thought of something. It could all come down to the DACs (or more specifically how the DACs are implemented). Here’s why...

The quality of the DACs and how well they are implemented can have a noticeable affect on the sound quality of CD players and pro sound cards (I’m making generalizations right now. We can discuss the need for a multi-thousand dollar CD player at another time). I guess it could be the same for receivers.

Although, it is generally accepted that if two similarly designed sound cards use the same DACs, then they will sound almost identical – regardless of which company makes it. When choosing between such sound cards, it all comes down to features and the stability of the drivers.

What does this have to do with receivers? Even though designing a receiver is a lot more complex than designing a sound card, maybe the same general rules apply. If two receivers use similar DACs and they are well implemented, then, if either receiver is used as a pre/pro, they will sound about the same.

What do you think? Does anything I just said make sense? Or maybe it’s just that it’s about 5:15 a.m. here and I’m suffering from not enough sleep…

Later,
B

P.S. - Please keep your opinions and incite coming.

 

[Rip Van Woofer]

The euphonic coloration of tube gear is often wildly overstated; sure, some of it measures badly, but a lot of it doesn't. Certainly there's mounds of evidence stating that the diff between .1% THD & .001 is totally inaudible with music, so even fairly large amounts can't account for the supposed difference.

True. My point was that maybe the tube outfit did have audible coloration -- unlike modern SS gear -- so that it was simply more likely that an audible difference would occur than between two pieces of SS gear. I know there is sonically transparent tube gear out there (and that the glowing glass bottles are sufficient in themselves to convince many 'philes that sonic magic is occurring).

On my "Audio Wisdom" page I have a link to a site where you can actually listen to varying degrees of harmonic distortion in brief music samples. I would be embarrassed to tell you how high the distortion had to be before I could hear it! My rationalization was that I was only using my dinky computer speakers. Yeah, that's it...fer sure!

You know, one of the rude shocks when I got back into audio after so many years away was, "hey, where's Stereo Review?!?" Kind of like that scene in Romancing the Stone(?) where the hero who has been a jungle pilot finds out the Doobie Brothers broke up years ago.

BTW, the S&V site has reprints of several Julian Hirsh articles to download, in memoriam.

And hey, I have some tube audio gear myself: a funky old Heathkit signal generator I got off of eBay! Works, too!