I've been looking into my Squeezebox Receiver (SBR) specifications and I've come across some figures I don't understand. Maybe one of the resident experts could help explain.
In the SBR is a Wolfson WM8522 DAC. The manuafacturers of this DAC unit claim a THD+N value of -85dB. I've attached the spec. sheet. Logitech then go and put it into a Squeezebox Receiver and get a THD+N value of -88dB? You've somehow got an extra 3dB reduction in THD+N from adding extra circuits after the DAC - effectively managing to undistort an already distorted signal. The same applies to the whole range: SBR: DAC THD+N -85dB SBR THD+N "less than -88dB" SB3: DAC THD+N -90.5dB SB3 THD+N "less than -93.5dB" Transporter: DAC THD+N -100dB Transporter THD+N "-106dB" Clearly there will be manufacturing variation between circuitry and some will be marginally better than others, but making a claim that your product can in any way normally produce a better output than the DAC contained within it is, in my eyes, just plain wrong. Unless you can somehow explain how this could be? Squeezebox take the DAC, add in some extra components, an LED screen and some wifi antennas and still manage a LOWER distortion than that provided by the source DAC - despite all these potential source of noise. How? Thanks in advance for any information. Ben +-------------------------------------------------------------------+ |Filename: WM8522.pdf | |Download: http://forums.slimdevices.com/attachment.php?attachmentid=6241| +-------------------------------------------------------------------+ -- jaffacake Ben - eco conscious techie and author of Jaffa's Green Blog - http://www.jaffacake.net ------------------------------------------------------------------------ jaffacake's Profile: http://forums.slimdevices.com/member.php?userid=3206 View this thread: http://forums.slimdevices.com/showthread.php?t=55083 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/audiophiles
