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Author Topic: Audiophoolery  (Read 72147 times)
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W1DAN
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« Reply #75 on: May 26, 2006, 02:36:01 PM »

Hi Bear and all:

Thanks for all the input. To counter what you stated below:

"Julian Hirsch never found *anything*. Those early 70's articles are a joke. Back then TIM wasn't even well understood. The State-Of-The-Art has come a long way since then. There is no doubt that R, L & C are the dominating factors in cables, and there is no doubt that variations in RLC absolutely can and do cause clearly audible and measureable variations in amplifier output. Degree plays a role, but surprisingly small variations are measureable and in a really clean low distortion system without masking effects can and are audible. Important to you or the average joe? Probably not. Doesn't mean it is BS."

In my oipinion Julian Hirsch was one of the last true audio engineering consumer equipment testers that exist. Him and Len Feldman. They're both gone now. I find that today's "reviews" have no numbers and tout the audio sound of a piece of gear with adverbs instead of true numbers. Junian used a Sound technology test set, which is nothing to sneeze at. He knew his numbers and they are solid to this day. In this article (late 70's early 80's) he also used A/B/X blind testing. In both the numbers he took and the blind tests there was no difference between the cheap zip cord and the expensive speaker wire. TIM was known then to be from many things like amplifier bandwidth limiting with negative feedback around it. I agree today the numbers achieved are alot better than then, but Julian measured them accurately.

I agree that RLC can affect things in the audio range...like runing 2000 feet if Belden 8451 with a 600 ohm source will cause HF loss due to capacity. However I feel that with an audio amp designed to run an 8 ohm speaker, 10 feet of zip cord will have maybe a few hundred PF of capacity. At 8 ohms the 3db point is above the audio range. I run a Hafler 200w power amp with the really thin radio shack zip cord into a set of Ohm B speakers. Passive preamp with an SACD player.

As far as recording is concerned, their goal is to faithfully record a performance. Same as yours. They spend $$ for better recording gear all the time. I am truly amazed at the sound quality that was obtained even in the early 1940's. That tells me that basic engineering laws and numbers worked then.

As far as the audio salesman I witnessed, he owned the store for about 25 years. He knew alot about audio and electronics. It was BS and I almost called him on it. Pure BS.

Now I agree that some things can improve sound (better supplies, stable designs, not using cheap electrolytic caps in the path). Many things like those fuses and speaker cone feet do not.

So in my opinion, I will rely on the numbers and listen for myself. Other opinions are fine too for them.

I in no way wish to degrade anyone personally and enjoy this discussion. There are many good people with opinions. So I hope to keep this conversation in an honorly and respectful way. I hope I have not offended anyone personally.

73
Dan
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W1RKW
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« Reply #76 on: May 26, 2006, 02:53:37 PM »

Audiophoolery or non-audiophoolery is pointless for nearly any level of audiosystem one has if surrounding environmental acoustics suck. 
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Bob
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2ZE
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« Reply #77 on: May 26, 2006, 03:31:29 PM »

I have been following this thread with some interest and waiting to see where it would go. I think both sides of the argument have very valid points, but Dan hit on perfectly. You just cannot change or argue imperical data gathered in a scientific manner. Alot of audiophools out there just see these ad's and go nuts buying anything that might improve their listening experience, and convince thenselves that it made a difference.yet there are audiophiles that recognize what will make a difference, and apply it correctly. I think alot of them get overshadowed, but also I feel they are in a very small minority.
A good example would be this:
Say you have a $5 POS violin bought in a second hand store Vs. a Stradivarious. To me, niether would make a difference because I cannot play the violin. Both would sound awful in my hands. Now take someone like Izaac Perlman ( I may have misspelled him name), he could make either one sound incredible. However, he uses a Strad. because he can distinguish the sound between the 2. Same goes in high end HI-FI, and same goes in HI-FI amatuer band AM. I can recall numerous times I have heard guys on the air installing some wiz bang gadget, and convincing themselves it was improving thier station somehow, until someone chimed in "what happened to your audio, OM....". It can be a 2 way street.
Point is: educate yourself and make informed desicions, listen to both sides of an argument, and go from there. Cool
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The Slab Bacon
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« Reply #78 on: May 26, 2006, 04:21:49 PM »

Pigmeat, Hmmmm......................... what happened to bacobits??  Looks like soomeone iis getting upset............

As far as being a ham, you prolly have been lisenced longer than me, seeing that you have a WB call and Mine is a KB call. So what, at least I am active and on the air!!
I have looked back through my last 5 years of logs and scratch pads, Your call doesnt appear anywhere in them. Hmm....................

Most of you audiofools just live to carry your obsession to extremes!

As far as white man goes I do not consider myself "white" by the W.A.S.P. definition,
I am full blooded Sicillian, and proud of all 270lbs of it!!

As far as double blind tests and subtle differences go here is one to sink your teeth into:
         How about a double blind taste test, I can tell the difference between fresh garlic and dry powdered garlic in my spaghetti sauce. How about a double blind taste test. And if that doesnt work, I have 2 good recipes for pickled eggplant.

Dear Mr Beargrease You cannot upset me, Give it up now. I will be the one poking the stick Grin Grin
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                                                        (with the fat meat shakin)
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W9GT
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« Reply #79 on: May 26, 2006, 05:39:40 PM »

What would be really interesting in all of this controversy would be for someone to produce some meaningful empirical data to support the case.  If any of this “high end”
witchdoctor-certified stuff could produce any truly measurable improvement in actual audio quality and/or response range, it might be worthy of respect.  I have never seen any real data to support the premise that any of this stuff really makes a meaningful difference.  It is all subjective.   By meaningful difference, I mean enough of a change that the human ear could actually discern a difference or improvement.  Not just an imagined difference, but something that could be heard by most people with average hearing.  I believe that it has been repeatedly proven by the telecommunications industry in extensive laboratory testing performed repeatedly since the 1930’s that it takes a minimum of a 3 or 4 dB difference for most people to detect any change. 

Oh well, why worry about ethics or scruples when there is an easy buck in it?

73,  Jack, W9GT Smiley
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John Holotko
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« Reply #80 on: May 26, 2006, 05:45:40 PM »

Pigmeat, Hmmmm......................... what happened to bacobits??  Looks like soomeone iis getting upset............

As far as being a ham, you prolly have been lisenced longer than me, seeing that you have a WB call and Mine is a KB call. So what, at least I am active and on the air!!
I have looked back through my last 5 years of logs and scratch pads, Your call doesnt appear anywhere in them. Hmm....................

Most of you audiofools just live to carry your obsession to extremes!

As far as white man goes I do not consider myself "white" by the W.A.S.P. definition,
I am full blooded Sicillian, and proud of all 270lbs of it!!

As far as double blind tests and subtle differences go here is one to sink your teeth into:
         How about a double blind taste test, I can tell the difference between fresh garlic and dry powdered garlic in my spaghetti sauce. How about a double blind taste test. And if that doesnt work, I have 2 good recipes for pickled eggplant.

Dear Mr Beargrease You cannot upset me, Give it up now. I will be the one poking the stick Grin Grin
                                                             The Slab Bacon
                                                        (with the fat meat shakin)

Now you're talkin my langauge. Nothing like the taste of that fresh garlic when preparing a good sauce. And that pickled eggplant sounds very appetizing. If ever you wish to share one of those recipies I am all ears.  Smiley Smiley Smiley
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WBear2GCR
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« Reply #81 on: May 26, 2006, 06:05:25 PM »

Ok, well 2ZE and 1DAN come closest to a rational position, imho.

The BROAD BRUSH comes when someone writes like this: ...product XYZ is idiotic, you people who think abc are stupid audiophools. How would that play if you were a ham on an audio forum and someone said that "product XYZ for hams is idiotic, and these hams are hamidiots"?? How can anyone tell where one is drawing that line? Sounds to me like it is being drawn across the board.

The full understanding of TIM really didn't happen until way later than Matty Otala's articles... and probably until later than '85 for the most part...

Julian Hirsch and Len Feldman never published a review that said anything much. Stereo Review.
The contemporary mags in the US don't say much, but Stereophile does publish some reasonable FFT response curves. There are some foreign mags that fill in some of the blanks, fwiw.

Now, Porkmaster, ya wanna talk about extremes?? Check out some ham shacks and basements! That's extreme!! And, whatever, I think that there's nothing wrong with "going for it" with a creative and constructive hobby like ham radio or audio.

Check out the audio DIY hobby, it's fun and run parallel to DIY ham radio in many ways...

          _-_-WBear2GCR

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kc2ifr
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« Reply #82 on: May 26, 2006, 06:16:36 PM »

Bear,
I found the web site u posted http://www.americanwired.com/news/oswaldsmill/oswaldsmill.html to be great. This is not to say I agree with all that is stated there....but just to see what these guys are doing and the pics they posted is great. Looking at those toobs amps in full operation was a site to behold!!!! To bad the class E  ham stuff cant be that perdy..... Roll Eyes
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WBear2GCR
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« Reply #83 on: May 26, 2006, 06:36:19 PM »

What would be really interesting in all of this controversy would be for someone to produce some meaningful empirical data to support the case.  If any of this “high end”
witchdoctor-certified stuff could produce any truly measurable improvement in actual audio quality and/or response range, it might be worthy of respect.  I have never seen any real data to support the premise that any of this stuff really makes a meaningful difference.  It is all subjective.   By meaningful difference, I mean enough of a change that the human ear could actually discern a difference or improvement.  Not just an imagined difference, but something that could be heard by most people with average hearing.  I believe that it has been repeatedly proven by the telecommunications industry in extensive laboratory testing performed repeatedly since the 1930’s that it takes a minimum of a 3 or 4 dB difference for most people to detect any change. 

Oh well, why worry about ethics or scruples when there is an easy buck in it?

73,  Jack, W9GT Smiley


Ummm.. .this is not quite correct.

3-4db is quite easy to detect.

Of course the type of source plays a role.

The actual figures are that a 1.5dB difference is a jnd, or Just Noticeable Difference. Two jnds = 3dB (iirc).
Now, you can hear far less than 1.5dB, depending on how the difference is presented - the context and type of sound.

Furthermore, it has been scientifically shown that people can hear information that is below the noise floor.

So, the issue of hearing, and what can or can't be heard is neither simple nor straightforward.

And there is a whole lot of testing and studies on this general subject. That is part of the way that the various compression schemes for digital audio were arrived at. They found ways to eliminate data that the brain tends not to notice or find objectionable. That alone should be sufficient to give a strong clue that hearing is neither simple nor straightforward.

          _-_-WBear2GCR
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W1RKW
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« Reply #84 on: May 26, 2006, 06:38:18 PM »

I agree. I think the website is cool.  But... We now know where good transmitting tubes are going.

Bear,
I found the web site u posted http://www.americanwired.com/news/oswaldsmill/oswaldsmill.html to be great. This is not to say I agree with all that is stated there....but just to see what these guys are doing and the pics they posted is great. Looking at those toobs amps in full operation was a site to behold!!!! To bad the class E  ham stuff cant be that perdy..... Roll Eyes
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« Reply #85 on: May 26, 2006, 07:19:53 PM »

What would be really interesting in all of this controversy would be for someone to produce some meaningful empirical data to support the case.  If any of this “high end”
witchdoctor-certified stuff could produce any truly measurable improvement in actual audio quality and/or response range, it might be worthy of respect.  I have never seen any real data to support the premise that any of this stuff really makes a meaningful difference.  It is all subjective.   By meaningful difference, I mean enough of a change that the human ear could actually discern a difference or improvement.  Not just an imagined difference, but something that could be heard by most people with average hearing.  I believe that it has been repeatedly proven by the telecommunications industry in extensive laboratory testing performed repeatedly since the 1930’s that it takes a minimum of a 3 or 4 dB difference for most people to detect any change. 

Oh well, why worry about ethics or scruples when there is an easy buck in it?

73,  Jack, W9GT Smiley


Ummm.. .this is not quite correct.

3-4db is quite easy to detect.

Of course the type of source plays a role.

The actual figures are that a 1.5dB difference is a jnd, or Just Noticeable Difference. Two jnds = 3dB (iirc).
Now, you can hear far less than 1.5dB, depending on how the difference is presented - the context and type of sound.

Furthermore, it has been scientifically shown that people can hear information that is below the noise floor.

So, the issue of hearing, and what can or can't be heard is neither simple nor straightforward.

And there is a whole lot of testing and studies on this general subject. That is part of the way that the various compression schemes for digital audio were arrived at. They found ways to eliminate data that the brain tends not to notice or find objectionable. That alone should be sufficient to give a strong clue that hearing is neither simple nor straightforward.

          _-_-WBear2GCR

Bear, if the gimmick being advertized has real scientific backing and can produce measurable data that corresponds to something that can be heard then maybe the item being advertized is worth it. Otherwise it;'s notrhing more than a bunch of crooks ripping off people who have no idea what they are doing.It's like CB'ers who have no concept of the decibal system and how it corresponds to incresed S units.

Most of the advertised audipfool devices lack credible evidence. They are nothing more than ripoff scams taking advantage of peoples ignorance.
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The Slab Bacon
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« Reply #86 on: May 26, 2006, 07:58:25 PM »

Hmmm.............. I wuz wonderin when someone wuz gonna come up with audio grade knobs!!  There Ya go!!

Buy it now, for the descriminating audiophile only: NEW AUDIO GRADE KNOBS PRODUCE THE FINEST TESSITURA...........just $399.67 ea

only while supplies last.......................





Quality audio knobs will only set you back 485 clams.

http://www.referenceaudiomods.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=NOB_C37_C

You might want to give these a shot on that Ranger for my neighbor in Jersey.    Grin



Sam  /  KS2AM



Sam, Ya know I was having fun with it, I didnt really belive that some idiot would actually buy them!! Geeezzeee If someone would pay $485 for a wooden knob, what would they pay for a gold plated toilet seat with the promise of better sound?? I am flabergasted that anyone would actually buy them!! (come on Bear give us the reasons why it works).
Oh well Old P.T. was surely a profet, long ahead of his time!!
                                                                                         The Slab Bacon

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« Reply #87 on: May 26, 2006, 08:24:37 PM »

Bear,
       as far as all of your blind tests and other shake oil salesmanship tests, here is one thing to always remember. The "victim" is always open to the power of suggestiion!
If you seriously bellieve it is so, ot will be so no matter what. You can talk the victim into thinking that the "dingleberry deluxe" speaker wire sounds better.

I have told this story before, and I'm gonna tell it again, because it sure fits the audiofool mentality.

Years ago I was in the automotive repair trade. Next door to the shop that I was working at was a hair salon. Robert, the owner of the salon had worked a deal with the owner of the shop that I worked at. It was that we would fix his cars for free
(he paid for the parts) and he would cut our hair for free. It had gotten to the point that I would never live long enough to collect all of the haircuts that he owed me, and he was getting to be a real pain in the ass.
       He came over one day complaining that his car "just wasnt running right" I was in a bad mood that and didnt feel like dealing with him. I told him to park the car at the top of the lot and I would look at it later on. I later walked over to the car and raised the hood. I let the car sit all day with the hood open, but never touched it otherwise. He came by around 6:00 and asked me if it was done. I told him that I had finished, but never got around to closing the hood. He drove the car away that evening.  The next morning he came over to me and said "I dont know what you did to it but it has NEVER run this good"

This goes to say one hell of a lot about the power of suggestion!! If you really believe it is so it will be so!! I am no psychologist, but isnt this how hypnotism works?

Now enter the audiofools, rug merchants, snake oil salesmen, and maybe Mr Bear!

The P.T.Barnum effect is still alive and well!! Long Live P.T. Grin Grin

I could go on and on with this, but you know what Murphy said: Never argue with a fool because sooner or later no one will be able to tell the difference"!!
                                                            The Slab Bacon   
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The Slab Bacon
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« Reply #88 on: May 26, 2006, 08:28:06 PM »


Now you're talkin my langauge. Nothing like the taste of that fresh garlic when preparing a good sauce. And that pickled eggplant sounds very appetizing. If ever you wish to share one of those recipies I am all ears.  Smiley Smiley Smiley

John,
        If youu come down for my "Post timmonium party" You can expeirence it firat hand!!

                                                                            The Slab Bacon
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Steve - WB3HUZ
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« Reply #89 on: May 26, 2006, 09:02:25 PM »

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Furthermore, it has been scientifically shown that people can hear information that is below the noise floor.


I'd love to see this scientific documentation. Where can I read it?
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WBear2GCR
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« Reply #90 on: May 26, 2006, 10:06:13 PM »



Good question.

I do not have a ready answer.

The topic was discussed in some depth on either rec.audio.high-end (inhabited by rabid "objectivists") or another forum, probably rahe.

I am fairly sure that the idea was that one could hear single tones belowa noise floor. But I don't think this is in dispute amongst the Phd crowd that deal in hearing/perception. I think you'd have to try for a google on it, or search rahe and maybe hit it - alternately ping a Phd in perception - they'd likely know the reference well. I am sorry, I do not.

The resident specialist on that topic is no longer participating, as he was at Bell Labs, running a department that did nothing but this perception and codec work, but left when it was dismantled a few years ago when AT&T was more or less scuttled. He would have known off the top of his head. Dunno where he is now, but he's not on that USENET group now.

You could post there or on other forums and see if someone pops up with a citation.

As far as 0.22dBW being audibly detectable, it might well be. Not in everyday music or voice, certainly. But scary small changes are audible with pink noise (from a tweeter for example) and very very small changes of capacitance or inductance in an xover... try it some time for yourself, you'll be very surprised at what you can hear that way and not with music or voice as the source. Quite revealing, actually!  Cheesy

In practice, when I am setting up or "voicing" a xover for a given speaker, using the measurements available (FFT boxes) with listening via pink noise certainly helps to "get it right." The FFT + computer simulations for the rough values always looks very good on paper. When you listen to it, it is usually pretty good. But once you work on the thing with the pink noise, per driver, and per pairs, then for the whole system, one usually finds that the result is "more right." And it's not bias or self delusion at work. I suppose it could be, but I tend to be a skeptic in these things and am not prone to thinking changes are better because they are changes, and have heard and seen far too much to be swayed by those usual biasing factors. But again that is only my opinion here.

The apocraphyl (sp?) auto mechanic story is no where as good as the story published by Dick Pierce regarding the Marantz 10B tuner alignment... similar, of course. No denying that people can and are swayed by appearances.

As I said, you all can come here and decide for yourself, being a skeptic you won't want to hear any differences, so you won't unless they are there. I know it will only be single blind, but in truth that is enough, and I can certainly randomize it sufficiently. You can decide for yourself. Who knows, you might not hear anything at all. I don't mind one bit.

       _-_-WBear2GCR
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Steve - WB3HUZ
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« Reply #91 on: May 26, 2006, 10:20:34 PM »

I'll dig around AES and the likes. Any written stuff should have wound up there.

I've made a lot of acoustic measurements in the controlled environment of an anechoic chamber. Getting repeatable measurements with less than a dB of variation was very difficult. Doing something at 0.22 seems to me to be unlikely, let alone audible. Not saying it's not, just in my experience, it would be very tough to do.

TNx for the leads.
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« Reply #92 on: May 26, 2006, 11:17:46 PM »

Ok, well 2ZE and 1DAN come closest to a rational position, imho.

The BROAD BRUSH comes when someone writes like this: ...product XYZ is idiotic, you people who think abc are stupid audiophools. How would that play if you were a ham on an audio forum and someone said that "product XYZ for hams is idiotic, and these hams are hamidiots"?? How can anyone tell where one is drawing that line? Sounds to me like it is being drawn across the board.


No, people  here are saying that if you buy junk that does nothing and has no rational basis for what the seller claims then the person is an audiofool. Persons who make sensible purchases of real devices that can really improve quality based on real measurement are audiophiles.
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« Reply #93 on: May 27, 2006, 01:45:15 AM »

Had an experience with high-end audio stuff that's illuminating to me....

I needed a phono pre-amp...the receiver I had with a phono input blew up & that's what I had been using.  I tried two different cheap devices and neither really did the job.

Then, to replace the receiver that blew up I got one of those Tivoli (Kloss...e.g. KLH) Model Twos, and I wanted to get a preamp to give it a phono input.

The high end shop where I got the Model Two convinced me that the Creek preamp ($250) was a good fit.  This is after I really pressed them about is it overkill for my turntable (Fisher MT-640) and the model two.  And yes, they were unwavering in their belief that that was the preamp that's appropriate.

OK, so I bouht it and asked about hook-up cables.  The sold me a Monster Cable Two RCA plugs to 1/8" phone plug for about $30.

I bit and bought it, even though I thought that, WTF? that cable should be about $5.  I might be getting ripped off here, but then again, everything about the shop said they know what they're doing.

So I took the preamp and cable home, hooked it up, and was rewarded with sound that SCREAMED that the preamp I got perfomed AWESOMELY!  Wow...the way it sounds says that every stereo receiver or preampI've ever owend had crap for the phono input, and that includes a Dynaco PAS-3.  So, they did, indeed, sell me the preamp that was totally appropriate.

Now...that $30.00 cable.

It is probable that if I would've gotten a $5 cable from Radio Jack, it would've sounded just as good.

But it is also truie that the Monster Cable cable I paid dearly for is very obviously much better constructed.  The defining thing there is that when I plug the 1/8" phone plug into the Model Two, it's hard to get it aligned right...that means to me that the tolerance on the mechanical dimensions are much tighter than on cheap cables.  Does it make it sound better?  Probably not.  Will it last forever, and  is it well made?  Absolutely.  Is this worth and extra $25?  You be the judge.

OK...that shop really knows what they're doing, and, probably, would never sell $10,0000 speaker cable.  And if they did, the reason they'd do it is because some of their customers expect them to sell stuff like that.  After all, they ARE an ultra high-end place.

And if that's how they pay the rent so that I can buy the really good stuff that doesn't require a second mortgage, hey, thanks, guys who buy the really expensive stuff for helping them pay the bills.

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« Reply #94 on: May 27, 2006, 01:49:37 AM »

Quote
The rack is enclosed in glass for safety reasons (the RCA 845 amps were originally in a metal cage with pressure switches to shut off power if the cage was breached.) The RCA 845 amps were first used in the Disney Fantasia road show, a legendary production which was arguably the very first time multi channel super hi fi was attempted. Each amp weighs over 150lbs. Output in class A of minimum 60 watts.

Hmmm.  I use a pair of 845's to drive the 805 modulator on one of my homebrew rigs.  Run full voltage on them, as recommended by RCA (1250 volts).  I don't use any pressure swictches or have any glass panels or metal cages around them.  They merely sit in their EF Johnson sockets, mounted on the chassis in a vertical position, as RCA has recommended for over six decades, and they get plenty of ventilation in my open back relay rack.  They have worked fine just like that ever since I built that modulator in the early 90's.
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« Reply #95 on: May 27, 2006, 03:53:17 AM »

Actually any electronic reproduction of music or speech sounds terrible to my ears. So far inferior to the sound of a live voice or music played live. Then there is the added psychoacoustic depreciation in which simply knowing it is electronically reproduced and not live makes it sound even worst to my extremely critican and discerning ears. That's why I own no audio reproduction equipment. If I cannot listen to my music live I don't want to hear it.
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« Reply #96 on: May 27, 2006, 07:31:22 AM »

Hi All:

I am amazed at the number of messages since I left yesterday afternoon. Hot topic!

My opinion on phono preamps (yawn!)....

I used a number of the lesser expensive ones until I built a couple of circuits in the Walter Jung Op Amp Applications book in the early 1980's. They used the normal NE5534 op amp and sounded great for my cash. I learned then that splitting the EQ up a bit (and also using some passive EQ between the op amp stages) can help the sound. Since then I use an old Radio Systems broadcast preamp that I bought at Hosstraders for $15.00. It has one of the best sounds I have found for it's price.

As far as the things that Bear likes:

I am interested in the science behind them. If you can provide AES papers or other documentation, I would enjoy reading them. One frustration I have is the fact that today's reviews no longer have much test data or theory of circuit design, which is what I enjoy. There is some good stuff out there, but also alot of snake oil.

So...can you provide test data as wo why you like a certain type of speaker cable over zip cord? Have you blind A/B's this with a friend or even had a friend blind A/B's this for you using your setup? Give us documentation that supports your opinion. BTW, in an A/B test I can hear about 1db difference using tones. I cannot hear in the noise floor. In a non-A/B test my difference detection is much worse.

In the end an actual concert is much better than reproduction. I have never been able to get close to an actual performance, even while listening to very expensive systems. Try the Boston Symphony in Symphony hall or a large big band concert. The concerts blow me away, and when I go home and listen to my halfway decent stereo, I am let down, but then I accept it. Also When I recall a tune, I do not remember how good the stereo wounded, I just hear the tune without remembering if it came through a transistor radio or a high end stereo.

Thanks and happy Memorial Day weekend!

73,
Dan
W1DAN
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Ian VK3KRI
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« Reply #97 on: May 27, 2006, 08:04:46 AM »

Quote
Furthermore, it has been scientifically shown that people can hear information that is below the noise floor.


I'd love to see this scientific documentation. Where can I read it?

My understanding is that for a single tone, the masking due to noise is for a small band around that tone, eg at 1K hz , most masking is due to the bands 950 hz to 1050 Hz.  If the signal is 'X' dB above the noise in this band it can be heard.
If the noise is white noise , the sum of the noise across the whole audio band may be greater than the tone.
In fact in my 'lets try this now'  test using the noise from a rx as the noise source, mixed with a 1Khz tone, and the resultant measurd with an audio level meter, I can easily pick a tone 10dB below the noise and I'm ptretty sure I can pick 15dB below.
 (Noise BW = RX BW ~= 4.5Khz ,  transducer = HD 457 'phones)
Of course the noise floor on even a substanderd 'hifi' setup is considrably belowthe noise floor on a HF reciver with a weak signal.
                                     Ian VK3KRI 
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WBear2GCR
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Brrrr- it's cold in the shack! Fire up the BIG RIG


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« Reply #98 on: May 27, 2006, 11:23:25 AM »

Actually any electronic reproduction of music or speech sounds terrible to my ears. So far inferior to the sound of a live voice or music played live. Then there is the added psychoacoustic depreciation in which simply knowing it is electronically reproduced and not live makes it sound even worst to my extremely critican and discerning ears. That's why I own no audio reproduction equipment. If I cannot listen to my music live I don't want to hear it.

Exactly the point!!

John, if you drive up north some time I'll try to show you some "reproduced" music that will not make you want to get up and leave the room. That's the aim of high-end. When high-end audio, be it inexpensive DIY or used gear or multi k$ gear, works properly you do not have the sensation that it is being reproduced mechanically or even that there are speakers in the room (yeah you see them, but the sound does not "come from them".)

 Grin

Oh, if you want to visit, please don't bring that iron shown in ur avatar...  Wink

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_-_- bear WB2GCR                   http://www.bearlabs.com
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« Reply #99 on: May 27, 2006, 12:05:03 PM »

Hi All:

I am amazed at the number of messages since I left yesterday afternoon. Hot topic!

My opinion on phono preamps (yawn!)....

I used a number of the lesser expensive ones until I built a couple of circuits in the Walter Jung Op Amp Applications book in the early 1980's. They used the normal NE5534 op amp and sounded great for my cash. I learned then that splitting the EQ up a bit (and also using some passive EQ between the op amp stages) can help the sound. Since then I use an old Radio Systems broadcast preamp that I bought at Hosstraders for $15.00. It has one of the best sounds I have found for it's price.


Ok, now we're getting somewhere!

I note how you say that splitting the EQ made some sort of improvement?  Wink
You're starting to catch on.
Now, take that same 5534 preamp and sub in some OPA2604 opamps and tell me what you hear.

Or try that with any circuit that uses 5532/5534... on paper there should be no audible differences.
 Grin

Quote
As far as the things that Bear likes:

I am interested in the science behind them. If you can provide AES papers or other documentation, I would enjoy reading them. One frustration I have is the fact that today's reviews no longer have much test data or theory of circuit design, which is what I enjoy. There is some good stuff out there, but also alot of snake oil.

Go to http://www.diyaudio.com
You will find a ton of in depth circuit discussion and analysis.

Quote
So...can you provide test data as wo why you like a certain type of speaker cable over zip cord? Have you blind A/B's this with a friend or even had a friend blind A/B's this for you using your setup? Give us documentation that supports your opinion. BTW, in an A/B test I can hear about 1db difference using tones. I cannot hear in the noise floor. In a non-A/B test my difference detection is much worse.

I have no discrete test data as to why I like one speaker cable over another.
I don't know that it is possible to generate any, since we have no direct correlation between the measureable parameters of a speaker cable (or an amplifier) and what we prefer when listening.
The only thing there is is empirical preference reports - be they A/B, A/B/X or not.

We have done single blind A/Bs many times.
They are not "valid" as far as statistical testing, afaik.

The bottom line is that there are so many confounding and masking factors that are uncontrolled in the published tests that even those can not be reliably and safely generalized and applied outside of the exact test conditions. There is significant cost and time involved with even trying to document something seemingly as basic as the measureable electronic/acoustical parameters of a given system used in a blind A/B test. It has not been done thus far. Which, imho, is a serious flaw or "fly in the ointment' as far as the published tests of this sort are concerned.

It comes simply down to something like this:
- you listen using zip cord
- you listing using speaker cable X

...you either hear some difference or you don't. Be it a blind test or not. Blind is fine by me.

In the case of the cables I prefer, in a vast majority of the cases one notices that the entire presentation of the sound is noticeably "more natural" and less "mechanical" sounding. If there is no difference, or not enough difference, you continue to use zip cord. Simple as that.


Quote
In the end an actual concert is much better than reproduction. I have never been able to get close to an actual performance, even while listening to very expensive systems. Try the Boston Symphony in Symphony hall or a large big band concert. The concerts blow me away, and when I go home and listen to my halfway decent stereo, I am let down, but then I accept it. Also When I recall a tune, I do not remember how good the stereo wounded, I just hear the tune without remembering if it came through a transistor radio or a high end stereo.

This is quite correct.

Most people get most of the needed "information" from a table top or "transistor" radio (remember the "7 transistor radio"??). Interestingly, many world class musicians and composers do not have expensive hi-fi systems at all. They don't need or want them, the music is inside their heads!! (...this is an important clue - see below)

But two things are happening, no three in a live NON-AMPLIFIED concert that do not happen in a home:
1- distributed sound source
2- lower distortion than a speaker
3- much LARGER space

In the home you can usually overcome 2 & 3, if you have a large space. You can not overcome 1, which plays into item 3. If you have never heard a very high quality system in a very LARGE room, you should - the effect is quite different than speakers in a normal or even larger size home environment, and much closer to a "live" performance than you might imagine! The home stereo can mimic item 1 IF the system is set up properly, the acoustical environment is well "managed". But it also needs to push the envelope of item 2 as far as possible, which a vast majority of speakers or any sort fail somewhere across the spectrum in doing. But as you approach these three things the presentation and quality of the reproduced sound becomes more and more plausible compared to the live performance.

Keep in mind that the sole purpose of playing back sound is to convince your brain that it is hearing something!That's all. Think of the system as merely providing "cues" that your brain interprets. The closer to "natural" or "real world" the cues appear the more the brain decides it is "real." Similarly, the clearer the cues are, the less you brain has to work to decipher the cues, the more "natural" and "live" the sound appears!

Think of the problem this way - music or sound is information over time; for any given segment of time the brain has to decipher the information & cues and reassemble that into a thing that is compreheniible; cues are sonic events that you have learned or know how to catagorize and recognize;  so segments are assembled into what we hear as music or speech.

It's like watching the scenery out the side window as you speed down the highway!!  Shocked

Now, the more time and effort the brain has to spend on getting the basic information from any given time/segment of sound, like when listening to a "signal down in the mud", the less time/brain cycles are available to decipher the subtler cues (IF they are there!). The converse corresponds to a +20 signal: "oh ur running some reverb on ur audio" or "I hear your cat"! This is why eaking the last little bit of fidelity out of a stereo system really does mean something! It makes it easier to decipher the basic sound, so that there is literally time to make out the subtle cues and details! It doesn't take much to mask or confound the process of discerning those details at all. (...part of that reason is that stereo or even 4/5 channel sound is a poor sample of the original)

Which, in part explains to a great extent why "your system" always sounds good to you. Your brain has learned how to cope with many of the masking and confounding factors, and has built an algorithm which enables you (to the extent possible) to grasp the whole. Whereas a person coming to visit does not posess that ability and hears something rather different!

It also explains why and where the differences lie between a basic stereo and one that is refined.   Grin

Hope that illuminates some of this...

Quote
Thanks and happy Memorial Day weekend!

73,
Dan
W1DAN


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_-_- bear WB2GCR                   http://www.bearlabs.com
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