Comparing Buckeye and VTV Purifi Amps

[Julf]

I have a friend who owns the Hypex nc502mp and I think it sounds good but the real problem with this amp is that the input sensitivity is too low in terms of voltage (2.8Volt). Modern preamplifiers have output levels above 5 volts and keeping them at 1.5 volts for normal listening (in the nc502mp), in my opinion lowers the dynamics too much. The effect is even greater with the DAC's digital attenuators. my two cents

Really? You are talking about 6 dB worst case. Do you actually hear hiss?

 

[GiFi]

In my opinion is much more than 6 db.
No hiss however

 

[Julf]

In my opinion is much more than 6 db.

Your opinion is noted, but mathematics and physics disagree.

No hiss however

Then there is no reduction in dynamics at all.

 

[GiFi]

Your opinion is noted, but mathematics and physics disagree.

Then there is no reduction in dynamics at all.

I'm referring to the performance of modern preamplifiers which show low dynamics at values of 1-1.5 volts. This preamp pairs best with older generation preamps. My two cents

 

[Julf]

I'm referring to the performance of modern preamplifiers which show low dynamics at values of 1-1.5 volts. This preamp pairs best with older generation preamps. My two cents

"Dynamics" (more properly "dynamic range") is the ratio (in dB) between the maximum signal and the noise floor. As long as the maximum output signal you can achieve doesn't change, and you can't hear the noise floor, the audible dynamic range is unaffected.

 

[GiFi]

I am aware of this fact but evidently I expressed myself in an inaccurate way since I intend to refer to musical dynamics if it can be called that. I hear a less satisfying and suppressed delivery at low volume levels from the preamps.

 

[Julf]

I am aware of this fact but evidently I expressed myself in an inaccurate way since I intend to refer to musical dynamics if it can be called that. I hear a less satisfying and suppressed delivery at low volume levels from the preamps.

Your subjective perception is noted.How did you match levels when doing the comparison? I assume you are aware of the fact that small differences in level/volume aren't perceived as volume differences, but as increased/decreased "clarity" and "dynamics".

 

[GiFi]

Sure, levels matched.
6 ears... .i don't know why but I think that even electronics need to work in an optimal range of voltages

 

[Julf]

Sure, levels matched.
6 ears... .i don't know why but I think that even electronics need to work in an optimal range of voltages

On the output side yes, but on the input / small signal side there is no "optimal" apart from theoretical dynamic range.

 

[GiFi]

maybe there are other parameters or correlations that affect the sound,
maybe the sonic characteristics of the buffers come into play more, who knows....

 

[Julf]

maybe there are other parameters or correlations that affect the sound,
maybe the sonic characteristics of the buffers come into play more, who knows....

Maybe there us a teapot in orbit around the sun. Maybe. Who knows.

 

[GiFi]

you are probably not open to confrontation. who knows

 

[Julf]

you are probably not open to confrontation. who knows

Confrontation? I am an engineer, I trust facts, objective evidence and rational discussion.

 

[GiFi]

I too am an engineer but when I can't find answers to phenomena I try to understand if there are other types of correlations or formulas and above all I am open to confrontation. I also try not to make fun of others because maybe they just want to understand and learn

 

[GiFi]

as far as I'm concerned it was a pleasure talking to you up to a certain point

 

[Julf]

I too am an engineer but when I can't find answers to phenomena I try to understand if there are other types of correlations or formulas and above all I am open to confrontation. I also try not to make fun of others because maybe they just want to understand and learn

The fun I was making was in a general sense and not aimed at you. I agree about looking for answers to phenomena, but I have learned to first verify objectively if the phenomena is explainable by psychological/perceptual factors before I start speculating about technical reasons.

 

[GiFi]

That's what I do too, everyday but I've encountered this voltages thing and wanted to share it with ASR. I wanted to do it in a constructive way, trying to give an explanation for the perceived minor dynamics but obviously you are so expert in the sector that you assure me that I cannot afford to make assumptions. Have a good life.

 

[Julf]

That's what I do too, everyday but I've encountered this voltages thing and wanted to share it with ASR. I wanted to do it in a constructive way, trying to give an explanation for the perceived minor dynamics but obviously you are so expert in the sector that you assure me that I cannot afford to make assumptions. Have a good life.

If you are an engineer, you undoubtedly are also familiar with scientific discourse and the importance of questioning and verification. One of the prime questions is always "how do I know that what I think/hear/see actually reflects reality?". I offered a common (and rational) reason for the perception you described. You seem to have taken it as a personal attack.

 

[GiFi]

if you read critically the posts we wrote to each other, maybe you discover that you immediately started to impose your thoughts in a not exactly polite way. I think ASR users are bored with these exchanges so I suggest you don't go any further. I just want to tell you that I know the principles of the experimental method very well and that the experimental approach has served to validate new hypotheses which then led to the successes of the technique and ultimately to transform them into the applications of the technology they enjoy everyone. I believe that making hypotheses to explain something that we perceive differently with our senses can only help us discover new methods of measurement or correlations and that this activity represents the very heart of science. I cannot disregard what we have heard and at present I can only speculate. Anyway, I had fun until post n.30.

 

[Julf]

if you read critically the posts we wrote to each other, maybe you discover that you immediately started to impose your thoughts in a not exactly polite way.

Apologies for a direct style of communication. I think it is mostly a cultural issue.

I cannot disregard what we have heard

Why not?

Anyway, I had fun until post n.30.

The one followed by my light teasing about the "maybes"? My apologies, no offense intended.