You stated "via balanced and unbalanced connection"
If you are using the Aleph 0 in balanced mode and the Aleph 3 in unbalanced, that is your problem. The Aleph P has 15 dB of gain using the balanced output, but only 9 dB using the unbalanced.
The only way I see to avoid using an attenuator is to use a splitter and drive both amps via their unbalanced inputs.
If you are using the Aleph 0 in balanced mode and the Aleph 3 in unbalanced, that is your problem. The Aleph P has 15 dB of gain using the balanced output, but only 9 dB using the unbalanced.
The only way I see to avoid using an attenuator is to use a splitter and drive both amps via their unbalanced inputs.