Strange Oscillation


Alright, I need to get to the bottom this. On a couple of CD's at certain passages, the music goes into an oscillation and won't quit until the volume is reduced or the disc stopped entirely. My playback source is an Ayre C-5xeMP, Plinius Tautoro pre and Plinius SA-103 amp. Interestingly this only happens on a few CD's and usually when there is a sustained chord such as from a keyboard note that is held or a sustained vocal. Two examples are Pink Floyd, Dark Side of the Moon, track one about mid point with the EMI Japan release CDP746001 Z. I also have the MFSL issue and it plays with no problem. Another example is Patricia Barber, Cafe Blue standard redbook release during a sustained high pitch vocal note and only at high volume. So what causes this to occur? It is obviously related to the CD itself since DSOTM MFSL issue plays just fine. Can anyone enlighten me?
128x128falconquest

Showing 1 response by williewonka

Falconquest - much of this thread points to issues unrelated to my comments below, but there are a couple of comments which made me wonder....

I do have first hand experience with a problematic Ayre amplifier and internal osculation issues.

The amp actually blew some internal components and the reason was the speaker cables, which had a sufficiently high capacitance, caused the amp to "oscilate" to a degree that some internal components were overloaded.

The cables in this case were from Cardas - replacing the cables with a pair of a lower capacitance resolved the issue completely.

The amp had previously been working with the Cardas cables, but the introduction of a high quality power cable was just enough to provide enough electrical energy to put it over the top.

The amp is now working perfectly well with the new power cable and a new pair of lower capacitance speaker cables.

BTW, the owner of the amp had also tried the Cardas cables on another high-current design amp and blew that amp also.

This oscillation issue is well documented on the web and effects only those solid state amps of a high current design - Ayre being one of them.

I don't know if this is your problem, but it is pretty easy to rule it out - simply try installing a different speaker cable.

Hope this helps