Today I noticed something odd with my BA-3B monos connected via XLR to my Aleph P1.7 pre whilst performing some THD measurements on the pre:
When the BA-3bs are turned off but still connected to the P1.7 the output of the P1.7 already starts to distort at 120mV output voltage (measured single ended) as if it was overloaded. When the BA-3bs are turned on or disconnected everything is hunky dory and distortion stays at or below 0,02% up to 5V (measured single ended) output of the pre. So far I checked the input DC resistance of the BA-3bs and measured the expected 48k. In a next step I´ll measure the current at 200mV or so.
Edit: The XLR cables are 5 meters
Has anybody experienced something odd like that or has some idea what might be going on?
It is not totally academic as I want to use the single ended outputs of the pre whilst the monoblocks are connected and turned off.
Many thanks
Ozo
When the BA-3bs are turned off but still connected to the P1.7 the output of the P1.7 already starts to distort at 120mV output voltage (measured single ended) as if it was overloaded. When the BA-3bs are turned on or disconnected everything is hunky dory and distortion stays at or below 0,02% up to 5V (measured single ended) output of the pre. So far I checked the input DC resistance of the BA-3bs and measured the expected 48k. In a next step I´ll measure the current at 200mV or so.
Edit: The XLR cables are 5 meters
Has anybody experienced something odd like that or has some idea what might be going on?
It is not totally academic as I want to use the single ended outputs of the pre whilst the monoblocks are connected and turned off.
Many thanks
Ozo
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