Dear friends: I come back on the RIAA eq subject because there is a subject of critical importance where almost no one ( and I say " almost " only because I don't read any single post on Agon but the true is that I never read nothing about. ) speaks on and that it is almost important as is the accuracy on the RIAA: inverse eq.RIAA interchannel deviation.
What this means?, well in a Phonolinepreamp or Phono stage we have the RIAA for the left channel and the one for the right channel. In a perfect world both must be exactly the same ( mimic ), any deviation between them degrade makes a signal degradation in many ways and yes you can hear it.
Take a look to some Phono stage measures through Stereophile on the RIAA subject and in all of those measurements ( SS or tube ) exist deviation between left and right channels RIAA curve of 0.1db ( for say the least ) and higher.
Now, we have to have not only " matched " inverse RIAA eq. curve channels but at the same importance level we must have both channels with the same gain, 0.1db of gain difference between channels well makes a " difference " in the performance and leave us faraway from the recording.
So IMHO are ( at least ) three critical areas to make justice to the recording through a Phonolinepreamp: inverse eq. RIAA accuracy, no interchannel deviation on the inverse eq. RIAA curve and matched gain in both channels.
As any one can see the Phonolinepreamp ( RIAA ) is truly a complex subject and a true challenge for any one that try to be near/truer to the recording.
Why am I posting about?, well because those subjects are IMHO of paramount importance and ( if the design take in count with care. ) make a great difference in the quality sound reproduction/performance .
Regards and enjoy the music.
Raul.
What this means?, well in a Phonolinepreamp or Phono stage we have the RIAA for the left channel and the one for the right channel. In a perfect world both must be exactly the same ( mimic ), any deviation between them degrade makes a signal degradation in many ways and yes you can hear it.
Take a look to some Phono stage measures through Stereophile on the RIAA subject and in all of those measurements ( SS or tube ) exist deviation between left and right channels RIAA curve of 0.1db ( for say the least ) and higher.
Now, we have to have not only " matched " inverse RIAA eq. curve channels but at the same importance level we must have both channels with the same gain, 0.1db of gain difference between channels well makes a " difference " in the performance and leave us faraway from the recording.
So IMHO are ( at least ) three critical areas to make justice to the recording through a Phonolinepreamp: inverse eq. RIAA accuracy, no interchannel deviation on the inverse eq. RIAA curve and matched gain in both channels.
As any one can see the Phonolinepreamp ( RIAA ) is truly a complex subject and a true challenge for any one that try to be near/truer to the recording.
Why am I posting about?, well because those subjects are IMHO of paramount importance and ( if the design take in count with care. ) make a great difference in the quality sound reproduction/performance .
Regards and enjoy the music.
Raul.