I have a Hafler DH-110 preamp. It works fine with a Kenwood power amp I have and a DIY class D amp. When I plug it in to my BA-3 that I recently finished, however, there is a loud hum. With one input connected, there is a slight hum. With both inputs connected, there is a loud hum. This occurs if the power to the preamp is on or off, but only if the preamp is plugged in.
The BA-3 works fine with the Schiit Freya preamp I use it with (haven't tried any other preamps). I've tried connecting it through a ground lifter, as well as disconnecting the power supply ground, with no change. Connecting the two inputs on the amp together also has no effect. I've grounded the input stage through a 47 ohm hum brewing resistor, which solved an earlier issue.
Of potential note: Both amps I've successfully used the DH-110 with are not grounded. The preamp I've used the BA-3 with is grounded.
I have handy, and have been reviewing, "How to Wire-up an Audio Amplifier" by Andrew Russell, no need to suggest it 😉
I'm not sure if this should be here, or in the Amplifier category, as I'm genuinely unsure which unit the problem lies with 😕
The BA-3 works fine with the Schiit Freya preamp I use it with (haven't tried any other preamps). I've tried connecting it through a ground lifter, as well as disconnecting the power supply ground, with no change. Connecting the two inputs on the amp together also has no effect. I've grounded the input stage through a 47 ohm hum brewing resistor, which solved an earlier issue.
Of potential note: Both amps I've successfully used the DH-110 with are not grounded. The preamp I've used the BA-3 with is grounded.
I have handy, and have been reviewing, "How to Wire-up an Audio Amplifier" by Andrew Russell, no need to suggest it 😉
I'm not sure if this should be here, or in the Amplifier category, as I'm genuinely unsure which unit the problem lies with 😕