Hello,
The dsp is connected to two TPA 3255 amps with unbalanced inputs.
First question, I connected AGND and + on the DSP outputs to, - and + of amp inputs, respectively, is this correct?
Both amps are powered by the same power supply, which only has a positive and negative lead. I have a ground loop between the negative terminal of both amps and across the outputs of the dsp (I get ground noise even when one of the amps is only connected to negative power in and even when the dsp is not powered on but with its outputs connected to the amps).
How should I break this ground loop across the DSP's balanced outputs?
Thanks!
The dsp is connected to two TPA 3255 amps with unbalanced inputs.
First question, I connected AGND and + on the DSP outputs to, - and + of amp inputs, respectively, is this correct?
Both amps are powered by the same power supply, which only has a positive and negative lead. I have a ground loop between the negative terminal of both amps and across the outputs of the dsp (I get ground noise even when one of the amps is only connected to negative power in and even when the dsp is not powered on but with its outputs connected to the amps).
How should I break this ground loop across the DSP's balanced outputs?
Thanks!
I could try to ground the dsp (while unpowered) to the negative of the power supply, which has a 0v potential to the negative input to the amp and thus AGND.
Would that help?
Would that help?
another question, when no music is playing, one of the amps moves the drivers in and out with a frequency of ca 1 Hz (even when it is the only amp powered on or hooked up to the DSP).
The other amp does not do this. Does anybody know what might be going on?
The other amp does not do this. Does anybody know what might be going on?
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Do you have the same problem when using only one amp? I've run into the same problem when using a DSP and powering two amps with a single power supply. No problem if I use a single amp. Also no problem if I use two amps, each with their own power supply.
Have the amp checked. Usually that would mean the main electrolytic capacitors in the amplifier
power supply are bad.
Which problem 😉 ?
I have the ground loop problem in only one of the amps (Han Zao) as long as even only the ground is connected to the other one (Shui Yuan) and with both connected to the outputs of the dsp (and dsp not even connected to a power source).
The Shui Yuan is the one with the motor boating problem with two distinct power supplies and both when connected to the mid driver as well as the both woofers.
If these are only the filter caps, then according to this post:
Those seem to be often replaced in anyway. Could these filter caps be faulty and causing both problems?