Well cant totally disagree... those old first gen HiFi gear was not something you would call highly accurate. Especially with a phonograph system. Though my ESL's were fairly neutral in midrange. Never-the less, HP continued to point out the differences between them and live performance sounds. Up until his death, he always had the best equipment the industry had to offer. If he really thought something had made a forward step in accuracy (to real sounds), then he would tend to keep the 'loaner' until something more accurate came to replace it, much to the consternation of the sometimes cash strapped mfr.
As time went by more and more subtle things could be detected and reported on and every year the top rated gear got published. He didn't know much about how the products were designed inside.... just if they were more or less true to the ref of live music.
It is up to the designer to improve the sound..... not just change it or sound different from brand X. But more realistic sounding over all or in some particular way really improved.
THx-RNMarsh
There is a lot more to accurate sound than these numbers.... but, the distortion is very low for the first 5-10 Watts .... where we use the amp most of the time. Doesn't tell you for example if it is mostly 2H or what.
THx-RNMarsh
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I have been successful with blind testing, so long as it was not ABX related. Sure, A-B blind is OK. I just don't bother with it anymore, as I am reasonably successful with 'sighted' testing. When I AM FOOLED, is when I just rely on measurements to tell me what an amp or preamp sounds like. This has created embarrassment every time my prediction did not work out. For example, when I designed the AD712 op amp in the front of my power amp, more than 20 years ago. What the heck, I knew the designer, I knew that he cared about IC quality, I was using the device in an 'easy' configuration, i.e. unity gain, line level, 2V max output ever expected, light loading, perhaps 25K ohm. What could go wrong? So I submitted the amp to 'Stereophile' and got quite a surprise listening opinion back. I had to design out the IC entirely, and have never looked back, except when the IC designer gets annoyed at me.
Fortunately, the modified amp passed 'Stereophile' with a solid 'B' rating, just what I hoped for at the time. We kept the 'B' rating until we made another major amp change, and I once again relied on my measurements instead of listening opinion, and we made another 'dud'!
My business partner Bob Crump and I took the amplifier virtually apart and put it back together and made it one of the best amps I have ever designed. Later, we used what we learned to build the Parasound JC-1 power amp that was even better. Today, we expect an 'A' rating or else we have failed somewhere. Yet, typical measurements would not tell you much as to why some amps sound great, and others sound lousy, even from the same designer.
Fortunately, the modified amp passed 'Stereophile' with a solid 'B' rating, just what I hoped for at the time. We kept the 'B' rating until we made another major amp change, and I once again relied on my measurements instead of listening opinion, and we made another 'dud'!
My business partner Bob Crump and I took the amplifier virtually apart and put it back together and made it one of the best amps I have ever designed. Later, we used what we learned to build the Parasound JC-1 power amp that was even better. Today, we expect an 'A' rating or else we have failed somewhere. Yet, typical measurements would not tell you much as to why some amps sound great, and others sound lousy, even from the same designer.
The AD712 story has been repeated by John to "put me in my place" for years now, I've learned to ignore it. $800,000,000 of satisfied customers and counting.
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I still used the AD711-12 for a long time for servo work. Worked OK. Today, I use the OPA134-2134 devices because they have better offset, are available, and cost effective.
In past years I have used the AD797 in instrumentation, and even in the prototype of the Parasound JC-3. I designed the AD825 (thanks for the samples Scott) in a prototype power amp that I made for Jack Bybee. I use that amp prototype in my office system. I will use anything that works well in my designs.
As for Stereophile 'peeking' I doubt that they did, because all of my power amps used AD711-12 IC's for servo and other housekeeping functions. I still don't know what went wrong, but I modified my own early units by just removing the input IC from its socket and putting a short wire across a couple of pins. I tried this with my own unit, my CTC business partner Carl Thompsen, and my office mate Brian Cheney. This worked OK, because we all then used single ended drive. The IC had been added to facilitate either single ended or balanced drive. This part of the design came from Taiwan, and I still can't see anything wrong with it. I replaced the IC with a class A biased pair of 2SK170 fets to implement balanced drive, and this is what we use today, including the new amp prototype that I worked on this week. Seems to work OK, but it can add a little 2'nd harmonic distortion to an otherwise balanced design.
In past years I have used the AD797 in instrumentation, and even in the prototype of the Parasound JC-3. I designed the AD825 (thanks for the samples Scott) in a prototype power amp that I made for Jack Bybee. I use that amp prototype in my office system. I will use anything that works well in my designs.
As for Stereophile 'peeking' I doubt that they did, because all of my power amps used AD711-12 IC's for servo and other housekeeping functions. I still don't know what went wrong, but I modified my own early units by just removing the input IC from its socket and putting a short wire across a couple of pins. I tried this with my own unit, my CTC business partner Carl Thompsen, and my office mate Brian Cheney. This worked OK, because we all then used single ended drive. The IC had been added to facilitate either single ended or balanced drive. This part of the design came from Taiwan, and I still can't see anything wrong with it. I replaced the IC with a class A biased pair of 2SK170 fets to implement balanced drive, and this is what we use today, including the new amp prototype that I worked on this week. Seems to work OK, but it can add a little 2'nd harmonic distortion to an otherwise balanced design.
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Regarding the word hearsay, if I were to tell you that I can hear undithered 16/44, that ought not be be considered hearsay even if you have concern that my claim might not be reliable. Hearsay would be if some third party told you I can hear undithered 16/44. In that case you would have to opportunity to ask me about it yourself to in order to judge my reliability.
Otherwise, if we use the word too loosely, one could assert that virtually anything someone ever said in their whole life could be considered heresay, because it might not be 100% reliably verifiable to the most stringent scientific standards. I don't think that's what the word is really for.
Hence, I still think it was not a good word choice to convey what I think you were trying to get at.
Anyway, how about we move along and let's see if we can get to a little more clarity on where we agree and disagree. For example, would you agree that a claim to the effect that at least some people can hear undithered 16/44, could reasonably be considered as settled science?
George, You are no doubt aware that certain subjects are restricted from discussion here due past problems. You are probably also aware that some threads have been closed due to very heated arguments, such as the recent thread about "what is hi-fi." And, things were also rather heated in this thread in regard to some claims of hearing abilities when I first came here. Why participate at all in that case? Why not? People calmed down and started behaving more civilly, and DIYAudio is the best audio website there is, so it's probably worth some effort to keep it functioning well.
As far as providing proof, you are welcome to come over to my place and I would be happy to show you that you too can hear undithered 16/44, and a few other things as well. However, if you want solid scientific proof that everybody can agree is very reliable, it would be a substantial project, and would probably cost some money as well. I don't see anybody here offering to do all the work and pay for it too, but I think it would be great if it could somehow be made to happen.
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Really? Search engines are bitches, aren't they:
Mr. Harley peeked and you got shafted by an eight legs hater, simple as that.
Chill Mark, but I take your advice.
Please note my complete statement - "In DJ world, sure it happens all the time....loud bass beat and alcohol and women lose all discretion lol."
In this scenario I am talking about young 'girls' at Discos, and in my experience is entirely accurate....just ask any DJ about the number of phone numbers they collect, even Ed Simon has been subject to this form of 'harassment'.
"This is pretty much the only time I have had women come up to the live desk, certainly the first time pleasing four women at the same time."
This scenario is entirely different.
In this situation the audience are 40's-60's age group, educated, well presented, cashed up and not drunk...iow discerning crowd who are there for the pleasure of the music.
I think we have all had the experience of female spouses when the home system is not good will say so in no uncertain terms, and when it is good will maybe offer compliments ...this live show example I give is the extension of this.
Where it gets interesting is that during the last break I treated the PA system to my filters and changed the sound from 'very good pub sound' to hifi clean, clear, fat and big (huge actually) and 'happy' sound.
After this (during the third and final set) is when these fine ladies came and voiced their compliments.
Several of us sounds guys regard this as particularly noteworthy.
In general conversations after the show and out in the beer garden, I heard several comments that the third set sounded so much better than the first two sets, and these coming from males and females who had no idea that I had a hand in transforming the system sound.
I have recently run some trials on a friends particular DJ system as preparation for fully kitting out this system...it will be interesting to see what crowd reactions he gets to what will be a uniquely good sounding DJ system playing to a range of audiences ranging from corporate functions to weddings etc.
There is deeper stuff going on in electric/electronic systems than what we learn in engineering class.
I do not yet have proper explanation or formal measurements (life has been in the way) for the effects I am exploring but they will come.
In the meantime it sure is fun (for me it's the ultimate fun) being able to walk up to any audio system and at will transform it from the typical harsh/electronic/mechanical sounding to clean, clear, musical and fun sounding.
The ultimate joy in this is watching crowd dynamics change to more friendly, bubbly and visibly happy, the room takes on a whole different atmosphere.
I'm talkin' bout a whole new concept in changing audio systems to 'analog' sounding, ie all the clarity of digital but none of the harshness of digital.
Dan.
Needless to say this whole sound of op-amps in servos is bogus and not substantiated by anything at all. I wish I could go back in time and make a youtube of a TAS listening session so everyone could enjoy a good laugh.
Yes, and different dither shapings are audible too.
I prefer non dithered....despite the low down 'dirt', recordings sound more 'real' and the noise can be 'listened through'.
Different dithers cause colourations that though on first listen may be 'pleasing', become identifiable and ultimately a hindrance.
Dan.
Back in my soundman days, I used to get about the same results you describe from turning up the volume. Particularly so in a club type setting, where people are talking and music is playing at the same time.
This is old, old news presented in the AES Journal decades ago, virtually anyone can hear it and NO ONE does it anymore.
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