I too received a response from Mathieu. My graph looks very similar to those already posted, although I have a curious upward kink at 14 kHz. This is particularly curious, as not only is this aspect different to the graphs referring to other phono stages, but it was not picked up in the analysis performed on my recording by @thumb5 and myself, see the first page of this thread. I think I will need to quiz Mathieu further on this point. Anyway, I have no idea why this aspect should be different in my case, but this is what Mathieu had to say:
I finally took some time this afternoon for an analysis.
Attached is the spectrum of your audio sample:
- The S-shape is due to the RIAA curved applied to the incoming stream. Without this curve it would be flat.
- The reference level is to be measured at 1kHz : approx -102dBc
- The bass level at 20 Hz is 20dB higher, as expected
- The treble level at 20 kHz should be 20dB lower, but it appears the noise floor increases after 14kHz
- The response of both channels is identical, no mismatch
- The response is deprived of any unwanted tone or resonance (which would immediately appear over the spectrum)
Feel free to share this picture and/or my comments on the forum. The obtained performance in no load mode is to my opinion excellent.
Next steps would be to redo the same measurements while playing a record with a sinewave in order to achieve and measure the SNR figure.
The perception of noise has always to be compared with the intensity of the reproduced signal (or the music)
I do use this one (can be found in many online shops)
https://store.acousticsounds.com/d/35532...t_Up_Tools
So what to make of all this? Clearly Mathieu thinks that the level of noise / hiss is acceptable in my case, which is also true of the others already analysed. In fact, in my case Mathieu is happy to state that the performance is "excellent".
My view has always been that the fact that the hiss is there is a little annoying, but as I am unaware of it when actually playing and listening to records, I am happy to consider the performance as acceptable. That said, as an audiophile, I consider that the very fact that there is some noise is itself is undesirable, and I would prefer if it was reduced or eliminated.
So this begs a question. Are all the phono stages performing in a similar way, or are those used by @Greg @Finn and others who find the level of hiss unacceptable actually under performing? Or to put in another way, are those of us more or less happy with the phono stage simply more tolerant of the hiss than others, or is there a hardware difference? We will know the answer to this if and when others send in there recordings. It should be noted that I have run the same cartridge as Finn (Candenza Black), which is at the lower end of cartridge outputs.
This also makes me think of some posts a while ago which suggested that the phono stage in the D-Premier was superior to that ultimately used in the Expert series and onwards. I have no idea if there is actually a technical difference with the D-Premier phono stage, but one thing that would be fascinating to do would be compare a "hiss" recording of a D-Premier phono stage with one from an Expert.
If there is anyone out there with a D-Premier who could make such a recording, I would be more than happy to make an equivalent recording with my Pro, using exactly the same phono stage settings.
It is a long shot, but is there anyone out there with a D-Premier willing to give this a try?
I finally took some time this afternoon for an analysis.
Attached is the spectrum of your audio sample:
- The S-shape is due to the RIAA curved applied to the incoming stream. Without this curve it would be flat.
- The reference level is to be measured at 1kHz : approx -102dBc
- The bass level at 20 Hz is 20dB higher, as expected
- The treble level at 20 kHz should be 20dB lower, but it appears the noise floor increases after 14kHz
- The response of both channels is identical, no mismatch
- The response is deprived of any unwanted tone or resonance (which would immediately appear over the spectrum)
Feel free to share this picture and/or my comments on the forum. The obtained performance in no load mode is to my opinion excellent.
Next steps would be to redo the same measurements while playing a record with a sinewave in order to achieve and measure the SNR figure.
The perception of noise has always to be compared with the intensity of the reproduced signal (or the music)
I do use this one (can be found in many online shops)
https://store.acousticsounds.com/d/35532...t_Up_Tools
So what to make of all this? Clearly Mathieu thinks that the level of noise / hiss is acceptable in my case, which is also true of the others already analysed. In fact, in my case Mathieu is happy to state that the performance is "excellent".
My view has always been that the fact that the hiss is there is a little annoying, but as I am unaware of it when actually playing and listening to records, I am happy to consider the performance as acceptable. That said, as an audiophile, I consider that the very fact that there is some noise is itself is undesirable, and I would prefer if it was reduced or eliminated.
So this begs a question. Are all the phono stages performing in a similar way, or are those used by @Greg @Finn and others who find the level of hiss unacceptable actually under performing? Or to put in another way, are those of us more or less happy with the phono stage simply more tolerant of the hiss than others, or is there a hardware difference? We will know the answer to this if and when others send in there recordings. It should be noted that I have run the same cartridge as Finn (Candenza Black), which is at the lower end of cartridge outputs.
This also makes me think of some posts a while ago which suggested that the phono stage in the D-Premier was superior to that ultimately used in the Expert series and onwards. I have no idea if there is actually a technical difference with the D-Premier phono stage, but one thing that would be fascinating to do would be compare a "hiss" recording of a D-Premier phono stage with one from an Expert.
If there is anyone out there with a D-Premier who could make such a recording, I would be more than happy to make an equivalent recording with my Pro, using exactly the same phono stage settings.
It is a long shot, but is there anyone out there with a D-Premier willing to give this a try?
1000 Pro - KEF Blade - iFi Zen Stream - Mutec REF10 - MC3+USB - Pro-Ject Signature 12
