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Old 8th November 2009, 02:46 AM   #2371
anatech is offline anatech  Canada
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Hi Joshua,
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This is because the experience is that there is no direct correlation, not necessarily, between how piece of audio gear measures and how it sounds.
Okay, I don't see too many faults with the beginning of your post, but I don't fully agree with the above line.

There is some correlation between some measurements and what is heard. Your statement is more of an absolute that does ignore what some engineers and technicians do know at present. I think that many issues being argued about may simply be because an extreme view is taken by at least one party.

I do know that many audio engineers (and technicians) will test sub-circuits by listening and measuring. There is more than enough evidence of this within the threads here. So maybe we should drop the extreme views. It is not reality, although we can both probably point to examples of all the ways that products can be engineered.

Quote:
Now, designers who don't hear differences between (well engineered) cables and who don't accept that such differences exist, will have listening evaluations that I cannot rely upon.
There are really two separate issues in the above quote. It's one thing to say that designers may not hear differences and yet another to show they will not accept the fact that audible differences may occur.

Most designers will not waste their time testing a cable design that is not well suited to the job at hand. There is a world of difference between a high impedance connection, and a low impedance (say ... balanced) connection. Then we have a couple major signal level differences, like line level and phono or preamp to amp connections. The differences are really about picking the connection that does the least damage to a signal - or allows the least amount of interference to occur. If we then allow the idea of altering the signal as some kind of tonal control, the very idea of transferring a signal from A to B has been violated. The other problem may come about defining which is the "best sounding" cable. In my books, a cable design that alters a signal is a failure as a design or application.

Remember, if you can hear a difference between cables, at least one of them is "damaging" the signal. Unacceptable.

So selling / auditioning cables without any form of pre-selection to match the circumstances is completely unprofessional, and just plain wrong.

Quote:
Moreover, naturally, they'd choose people with attitude similar to their own for the listening tests.
That's an unwarranted assumption on your part. Quite unfair to people who are honestly doing their best to get a truthful answer. In my own case, I have some people I trust for an opinion who's preferrences are fairly different from my own. Children are the best here. I also tell anyone who listens to anything for me that a critical review is far more useful to me than a positive response (ie. hurt my feelings, please!). I have colleagues who ask the same from me these days.

Most designers do not want to be surrounded by "yes men".

Quote:
This is in brief. If necessary, I'll expand.
No, I think you were pretty clear on that.

My own view is that it's odd for anyone to ignore options or any additional information. In your case, one of your stated criteria is to accept what you are being told, even though there is substantial economic pressure for a designer to lie about what they can hear or not. From some of your earlier comments, you have stated that you need to hear the product yourself before purchasing it. Yet, you actively ignore products on the flimsiest grounds. It just doesn't make any sense to me, given your experience especially.

-Chris
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Old 8th November 2009, 03:01 AM   #2372
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I take exception to the phrase:"...even though there is substantial economic pressure for a designer to lie about what they hear or not."
Let's look at this, it is mean spirited toward me, since it is put on THIS thread, but how much sense does it make in reality? IF a designer lies to anyone about his design, then he is also lying to himself, as well. He is not usually the sales, marketing or necessarily the manufacturing arm of the business. He is just the designer, surrounded by his data books, armed with his education and experience, and limited to the intended cost of the design and the parts at his disposal. A serious designer will do his best to do as good a job as possible, often depending on test equipment to make sure that the design meets at least a reasonable set of specs. Usually, a designer when finished with his effort will think it, (perhaps unfairly), as one of best of similar designs, both sonicially and aesthetically.
This is especially true of loudspeakers, but it is also true with electronic designs. You should had have seen the beam of pride that a certain young designer had, in my presence 35 years ago, when he showed the first BOSE power amp. Where is that amp, today? Everybody keep their Dyna Stereo 120, Quad 405? Now don't modify a designer's efforts, it is perfect sound from the get go. :_)
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Old 8th November 2009, 03:10 AM   #2373
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Hi John,
The interaction between different cartridges and the active circuits to amplify them can vary with loading. There have been MC phono circuits that oscillated with some cartridges. Denon comes to mind for one.

Loading will change the damping of the cartridge for one. You can also expect noise levels to change as the impedance is varied. Either way, I would expect these things to be audible.

For MM cartridge gain circuits, we are again concerned with terminating the cartridge into it's specified (by the manufacturer) load. Again, a perfectly audible change.

I know you are well aware of these things John, but for the benefit of our fellow members who are not used to dealing with a turntable. In fact, aside from the corrective equalization, amplifying a phono cartridge is pretty close to amplifying a dynamic microphone. Satisfying the loading requirements and keeping noise as low as reasonable possible.

So there are a couple of good reasons why terminating a cartridge is important.

-Chris
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Old 8th November 2009, 03:14 AM   #2374
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Chris, either prove your assertions or please let Syn08 answer the question. Have any measurements? You know, MC cartridges loaded with various loads measured with a test record, perhaps? Please, no 'handwaving' we need hard data.
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Old 8th November 2009, 04:15 AM   #2375
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Hi John,
Quote:
I take exception to the phrase:"...even though there is substantial economic pressure for a designer to lie about what they hear or not."
Let's look at this, it is mean spirited toward me, since it is put on THIS thread, but how much sense does it make in reality?
Why would you think any of this applies to you? Now I'm really confused, because I have never said or implied you are untruthful.

I was answering a specific question from Joshua. You've taken these comments out of context. So, let's look at this.
Quote:
even though there is substantial economic pressure for a designer to lie about what they hear or not
This is a completely true statement and does apply to some people in the audio business. It is critical that the person behind a design appears to have considered all aspects of a design. They must appear to be on the cutting edge in order to have a product that is acceptable to most of the high end purchasers. Example, Bob Carver is a master at packaging and presenting his equipment. He went as far as using Monster Cable in his amplifiers in order to appear concerned about the best sonic performance his product could deliver. Why? People at the time knew that Monster Cable was not cheap stuff, so why would a manufacturer use expensive parts unless it made a difference? In fact, any like product would have sounded as good, especially when one considers the parts between the outside end of the cable and the output jacks. Want more? Solid copper chassis's (Yamaha), copper plated chassis's (Yamaha later on), toroid power transformers (the industry) ... you get the idea.there are no shortage of fads used in order to make a product look like it's technologically superior to others. The viewpoints and beliefs of the design team, or the "name" behind the product becomes more important as the price goes up, or for the target market. True or not, it is critical that strong consumer beliefs are acknowledged. YOu can build the best - whatever, but it won;t matter if you can't sell them because it uses the wrong capacitors, wire, connectors. Well, the list goes on. Therefore, true or not, if the audiophile community thinks that you can hear differences in cables (sorry, they are called "interconnects" these days instead of "patch cords" way back when), the designer or lead engineer had better as well. The statements that Joshua just made the past few days are a perfect example of what I mean. Nothing here singles you out either John.

Quote:
IF a designer lies to anyone about his design, then he is also lying to himself, as well.
Exactly. There are many examples of this. That is why I pointed out that there are sometimes differences between what people sometimes say and what they actually believe.

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He is not usually the sales, marketing or necessarily the manufacturing arm of the business.
No, but any comments the designer makes will affect sales if they are not careful. The designer may be instructed as to what any responses are to be to specific questions.

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He is just the designer, surrounded by his data books, armed with his education and experience, and limited to the intended cost of the design and the parts at his disposal.
Now, that is the absolute truth. Problem is, some designers believe they are above these things. I can't name one who comes to mind, that person is not you and they are still active in the audio business.

Quote:
A serious designer will do his best to do as good a job as possible, often depending on test equipment to make sure that the design meets at least a reasonable set of specs. Usually, a designer when finished with his effort will think it, (perhaps unfairly), as one of best of similar designs, both sonicially and aesthetically.
I agree with you totally on this. Test equipment is required to verify that the published performance levels are achieved. However, test equipment is also great for tracking down problems that can crop up in a design as well. It's not unreasonable for a designer to believe they just created the best 'whatever". He has to justify all the effort. A designer has every reason to be proud to create something that survived budgetary pressures from above (or sideways!).

Quote:
This is especially true of loudspeakers, but it is also true with electronic designs.
Speakers are a whole different thing! Box dimensions and materials are at odds with the costs of building a speaker, and especially in the shipping of same. Add the heavier packing box construction and it's not hard to see how much shipping is going to hurt the budget. Then, warranty issues can really chew up profits (which is why the selling dealer was expected to repair speakers). Something along the lines of the Carver Amazing speakers (take your pick) can literally kill a company simply due to shipping damage. Shipping these in the winter in Canada is a very poor choice. You should see the total destruction caused by all those strong magnets breaking free and reorienting themselves. However, electronic items can also suffer from mechanical failures. Once a transformer breaks free and spends the trip rolling merrily back and forth, the item is typically not worth repair.

Quote:
You should had have seen the beam of pride that a certain young designer had, in my presence 35 years ago, when he showed the first BOSE power amp.
Those amps didn't possess any of the finer qualities expected in home audio amplifiers. I wasn't impressed with them.

Quote:
Where is that amp, today? Everybody keep their Dyna Stereo 120, Quad 405? Now don't modify a designer's efforts, it is perfect sound from the get go. :_)
Gone I hope, but there were far worse designs out there too. Some people actually like the old 120's, even Quad 303's. The 405s were a step or two up.
There are times when a design is so botched that changes are required just to keep them working. Then, there are those changes that do measurably improve the performance. Even a discontinued component can force a design change. But, these changes should only be attempted by a good audio technician.

Anyway, my previous post was in answer to a specific question. In no way was it connected to you.

-Chris
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Old 8th November 2009, 04:20 AM   #2376
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It is funny to read that capacitors in signal path are an absolute evil, then read that Sansui designs were "Wonderful"... Go figure... I remember some Sansui that used electrolytics between tube preamps and tube amps, among christmas tree lights of capacitors in switchable filters that are always in signal path... Lots of knobs and buttons on nice looking front panel, and roughly welded iron chassis... Power and output transformers close to each other, aligned magnet paths, hot tubes squeezed between them...
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Old 8th November 2009, 04:21 AM   #2377
anatech is offline anatech  Canada
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Hi John,
I actually did have data years ago when running my shop. The Denon oscillation problem is a matter of record. The were engineering change orders issued on that problem.


Can you see me?


Can you see me now?

Time for now John. I'll bet there are some papers on this, but I also know you have an exact knowledge of this subject too.

-Chris
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Old 8th November 2009, 04:40 AM   #2378
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That was just a bad design. Does Syn08 make designs that oscillate with source impedance and load interactions? I don't. In any case, that is NOT why Syn08 put an elaborate loading scheme in the front of his MC preamp.
Do you know the slew rate of the Quad 303? Any guesses? Typical Quad. This is perfect example of all knowingness by engineers.
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Old 8th November 2009, 04:51 AM   #2379
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Everyone, just to clarify things. I know of no published measurements of MC cartridges and loading, showing significant measured differences, yet many hear differences. Go figure. I just found an attempt at a loading change from 3 ohms to 1Kohm that made no significant difference in the high frequency output, that was made by a major audio test magazine, years ago. They tried to find a difference, but failed.
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Old 8th November 2009, 07:59 AM   #2380
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Quote:
Originally Posted by Joshua_G View Post
Yes, I'm interested in checking out designs made only by audio designers (engineers or not) who can hear differences between cables.
Joshua,

If a designer can hear the difference and can remove it (to his ears) with some eqalization is he still disqualified? Same goes for fixing an oscillation caused by particular amp/cable/speaker combination.
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