RandomEar
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- Feb 14, 2022
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OK, so this is an odd problem: I've recently bought an SMSL AO200 as a stop-gap solution, until I find a Hypex or Purify implementation I like. Now, I've had two units of the AO200 already and both exhibit a peculiar behaviour: When the amp is connected to at least one speaker and is not muted, the amp and the speaker emit a very high pitched, low volume hissing sound. It sounds sharp and also has some crackling character. Spectrum analysis is inconclusive because the noise isn't very loud, but results indicate a possible mix of 4/8/12 kHz tones + some other stuff.
I've now debugged this noise and found the following: The hissing/crackling is only emitted, when the amp has a connection to the tweeters of my ELAC 243. The speakers can be bi-amped and I tested it with only the base driver connected, which results in the amp being silent. Nothing else I did (different wall outlet, disconnecting/turning off all other devices in the room, connecting only the cable without speakers, re-routing the cable) changed anything in the outcome.
My conculsion is, that the amp is somehow "incompatible" with the frequency divider for the tweeter in my ELACs and seems to oscillate when connected to that. Did anybody else ever experience anything like this? Any tips on how to possibly fix this?
I've now debugged this noise and found the following: The hissing/crackling is only emitted, when the amp has a connection to the tweeters of my ELAC 243. The speakers can be bi-amped and I tested it with only the base driver connected, which results in the amp being silent. Nothing else I did (different wall outlet, disconnecting/turning off all other devices in the room, connecting only the cable without speakers, re-routing the cable) changed anything in the outcome.
My conculsion is, that the amp is somehow "incompatible" with the frequency divider for the tweeter in my ELACs and seems to oscillate when connected to that. Did anybody else ever experience anything like this? Any tips on how to possibly fix this?