Opinions on the role of the preamp in a modern single source system

[Gregadd]

I can't ever recall hearing anyone talk about a noise inherent in, or deliberately added to analog components to increase their fidelity.

Can noise affect stereo seperation?

 

[Phelonious Ponk]

Can noise affect stereo seperation?

Of course noise can affect separation. You know of a case of analog noise being used to improve separation?

Tim

 

[JackD201]

These?



Let's skip the fact that these don't relate to preamps for a moment. We know that the change in groove elasticity/tape hiss adds a noise akin to digital noise shaping, or we know it works like digital noise shaping to reduce distortion? They're two very different things.



And the answer is no, but I've seen no evidence of good analog noise other than the aforementioned thermionic noise in tubes. Analog audio has been around for many decades. Surely someone can point to/name/measure this "analog dither" if it exists. If it has the affect of increasing fidelity and it hasn't been codified and controlled by now, shame on the industry.



That question has been answered for decades, and the answer has been a founding audio design principle for as many decades -- one component presents more information than the next because it has lower noise, lower distortion. Because it obscures less information. This has been the goal of quality audio, and its founding premise for many, many years. The ideal? "A wire with gain." I've read a hundred variations on that concept repeated in studies, reviews, product literature, over and over again. I can't ever recall hearing anyone talk about a noise inherent in, or deliberately added to analog components to increase their fidelity.

Is this just a personal theory?

Tim

You seem to actually believe "straight wire with gain" has been accomplished. Surprise. It hasn't. That's what has been proven for decades not the ideal.

In the absence of the ideal, work has been management of noise and distortion. Can you understand this conceptual framework now?

You know what? Look this all up yourself. This thread has become as tiresome as the rant about auditory memory.

Audioexplorations, ask yourself about how much you trust your auditory memory the next time you answer your phone and instantly recognize the voice of the caller. You expecting that call? Regurgitated internet B-S.

I'm outta here. Can't believe I took the f-in time to share my experiences if all you wanted was apparently a chance to promote an agenda. Geez.

 

[JackD201]

Of course noise can affect separation. You know of a case of analog noise being used to improve separation?

Tim

Yes. Many. Find them yourself.

 

[AudioExplorations]

Audioexplorations, ask yourself about how much you trust your auditory memory the next time you answer your phone and instantly recognize the voice of the caller.

This is clearly not the same thing as trying to remember the slightest nuances in the playback of music! The human brain can only actively focus on one thing at a time, the treble, then the dynamics, then the width and depth of the sound stage. You then get up from your chair, switch around a bunch of cables at the back of your gear, sit back down and try to compare and contrast these aspects to what you heard 5 minutes ago. It is just not something the human brain can do with reliable results. Quick, instant A/B switching is the only way, which is not really possible in the context of this discussion, unless you add a separate switch.

Can't believe I took the f-in time to share my experiences if all you wanted was apparently a chance to promote an agenda. Geez.

No need to get upset, we are having an intellectual debate about a subject that people can never seem to agree on. It's interesting hearing everyone's POV and input. If you are leaving then thanks for the input you provided to the discussion.

 

[Phelonious Ponk]

You seem to actually believe "straight wire with gain" has been accomplished.

Nope. Just believe it's the theoretical ideal. Think I said that, actually.

Tim

 

[JackD201]

Yeah? What makes it so different from remembering the formant structure of a person's voice? Do we use a different part of our brains? I'm talking about identification which is a prerequisite for any qualitative assessment. It is the latter that is unreliable but not because of quality of memory but rather what the memory is composed of, abstract impressions. That in turn can be addressed with training where the abstract can be translated into ranges of metrics. At least get that straight.

 

[AudioExplorations]

Yeah? What makes it so different from remembering the formant structure of a person's voice?

The differences are much less pronounced, more easily forgotten, and difficult to compare. With instant switching you could flip back and forth as many times as you need to to focus and compare a specific aspect. This is the level of detail that would be needed in a preamp/no preamp comparison.

 

[andromedaaudio]

Well one can talk about it for ages i guess , as goes with many things the proof of the pudding is in the eating

 

[AudioExplorations]

Well one can talk about it for ages i guess , as goes with many things the proof of the pudding is in the eating

Agree! I might take you up on that offer by the way!

 

[andromedaaudio]

Sure .
You might like it maybe not

 

[mep]

Sure .
You might like it maybe not

Yeah, we will need to do a blind taste test to make sure there wasn't some expectation bias that the pudding might actually be good.

 

[garylkoh]

Yeah, we will need to do a blind taste test to make sure there wasn't some expectation bias that the pudding might actually be good.

I recommend Hapi Pudding

 

[AudioExplorations]

I was actually talking about andromeda's offer a few posts ago to carry out a listening test at his home in Amsterdam.

 

[mullard88]

Hi ack,

Just saw your post #43. What is it that you find hard to believe? I presume you are asking for a web link to the particular audiophile's system. Unfortunately, I do not.

 

[JackD201]

The differences are much less pronounced, more easily forgotten, and difficult to compare. With instant switching you could flip back and forth as many times as you need to to focus and compare a specific aspect. This is the level of detail that would be needed in a preamp/no preamp comparison.

Are you trying to rally support? If you actually read my post on how I compared, you'd see that I did use fast switching and how. Please direct me to your post which does the same.

 

[AudioExplorations]

Are you trying to rally support?

Not sure what you mean with this.

If you actually read my post on how I compared, you'd see that I did use fast switching and how.

Sorry, completely missed that. Why were you so interested in debating auditory memory then?

Please direct me to your post which does the same.

I never said anything about how I did the comparison. What I did was position my amp, source, and preamp on the coffee table infront of the listening position with the back panels facing and only a few feet away, and manually replug everything, which meant around a 5 second gap in the music. A switch is obviously a better way to do it.

 

[Phelonious Ponk]

@Tim...........I think what a lot of people are hearing, if operation without a pre-amp is technically sufficient (low impedance source with power to drive high impedance load), when they add a pre amp, is easy to understand when you look at those twin tone IMD tests (19 + 20 KHZ or whatever) in Stereophile, and golly gee, look at all those new signals popping up all over the place...thats just two tones, now add several dozen or more together......yes, distortion, BUT, depending on the flavor of those distortions you can hear "more" or less "detail".

I realize now that I should have started my own thread, should have asked a much narrower question about the technical requirements for properly driving an amplifier. That question was answered here, but a lot of others were raised by the way I went about my inquiry, pushing so hard on the how and why, and not just accepting people's experiences on face value. I'm helping a friend put together a single-source system. It will be different - bigger - than my own, and I wanted to know if, once the source has sufficient output and a quality volume control, there is any substantive advantage to adding a preamp.

The answer, it seems, is "Yes. If you hear one." Unless you have the money to buy a roomful of quality pres to switch in and out of a system until you're satisfied that you've answered that question and sold off all, or all but one, or unless you're willing to displace at least a part of your love of music with a passion for years and thousands of dollars in the pursuit of system synergy, it's not an answer. It's another whole series of questions. I guess I was really looking for "your output x needs to be between A and B if your amplifier z is between C and D." Can it be that simple? Perhaps not, but I think it's a lot closer to that simple than it is to this complicated. YMMV.

When I got subjective evaluations of emotional experiences instead of my answer, I pushed for data. That got interpreted as me not excepting people's experiences. The truth is I probably asked the wrong question in the first place. Sorry.

Tim

PS: Looking back through, I see that my question was answered, pretty definitively, by page 5. Had I bowed out at that point instead of challenging people to provide some substantive explanations for subjective experiences, this whole thing would probably have ended better. My apologies.

 

[Keith_W]

Tim you sometimes come across as a hard man to please. It takes guts to say what you did. Kudos to you.

 

[microstrip]

(...) The answer, it seems, is "Yes. If you hear one." Unless you have the money to buy a roomful of quality pres to switch in and out of a system until you're satisfied that you've answered that question and sold off all, or all but one, or unless you're willing to displace at least a part of your love of music with a passion for years and thousands of dollars in the pursuit of system synergy, it's not an answer. It's another whole series of questions. I guess I was really looking for "your output x needs to be between A and B if your amplifier z is between C and D." Can it be that simple? Perhaps not, but I think it's a lot closer to that simple than it is to this complicated. YMMV.

When I got subjective evaluations of emotional experiences instead of my answer, I pushed for data. That got interpreted as me not excepting people's experiences. The truth is I probably asked the wrong question in the first place. Sorry.

Tim

PS: Looking back through, I see that my question was answered, pretty definitively, by page 5. Had I bowed out at that point instead of challenging people to provide some substantive explanations for subjective experiences, this whole thing would probably have ended better. My apologies.

Tim,

No reason to apologize for anything, it was a very interesting thread. But IMHO your summary of the answering posts distorts the real value of the answers and opinions of the responders - you seem to have picked just those you needed to discredit high-end with your negative perspective.

And although I thought I understood what you wanted to know I am not sure any more. If you just want the electrical rules to properly transfer signals between outputs and inputs they only imply a few ratios between voltages and impedance of the circuits bonded with some common sense about signal to noise ratios. I used to deal with it in Basic Electronics. But as a few people explained the real problem has many variables and parameters, that can not be properly quantified for audio electronics amateurs, such as you and me. I am sure that people from Audio Research, Burmester, Krell, Mark Levinson and many others know why their own units optimally match to create the result they pretend. It is why they use very powerful electronics CAD programs with enormous simulation capability to design their circuits and have their own perceptual models of the effects of their designs. Contrary to your belief, the reason of the continuous improvements in high-end is the great knowledge of the designers about their profession.