Audio Precision Issue

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hello,

I have an Audio Precision Portable One Plus that seems to have developed a strange issue. At certain frequencies and levels, the distortion measurement reads 0.0000%. I know that the residual THD of the device is about .0015% from doing loopback measurements. It also passes its own self-test.

Can anyone enlighten me as to what this issue is, and how I can go about solving it?
 
A fault in the measurement amplifier section ?
The Dual Domain version in the analogue section residual THD has a spec of = 0.0025 % across 15Hz to 20kHz (80kHz bandwidth ) .


The Portable One /Plus etc was discontinued in 2010 (PIPA ) --P1 version discontinued in 1997 -- support status =unsupported

system two =unsupported 2016 .


As far as I know D.Self has /had an expensive Audio Precision Analyzer .
It seems its still available on upmarket "second user " company websites.
 
The OP,s version is a cheaper portable version it isn't a 2722 with a dis.of 0.0025 % - 15Hz-20kHz -80kHz bandwidth ,the 2722 has a lower distortion , my old 8903 (HP)-Agilent has slightly better dis. than Portable One although I built the JLH 0.001 % dis. analyzer .
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.