Geko
It just occurred to me
You amps have non polarized AC plugs which give you a 50 /50 chance of having the amps plugged in correctly
You will want to make sure you have both AC plugs in the wall with both polarized correctly.
If you look at the AC wires you will see little ribs on the power cords wire.
Try plugging both amps ribs to the right or in the positive ac wall slit and then try ribs to the left see what sounds best with a female voice.
You can confirm you are optimized with an AC Volt meter Measure AC volts then plug each amp one at a time into the ac wall outlet with the amps turned off and no interconnects to amps...
Now measure the amps ground voltage by taking VM probes from the amps ground chassis to ac wall sockets Ground
which is the round hole. Remove plug from wall and re insert it the other way and measure again
The lower the chassis ground the better the sound
Now mark the cords and always plug them in this way
Keep in mind these mono block amps work best with shorter runs of speaker wire 3 to 4 feet is ideal even if your uncle fritz gave you some hi Cap anaconda peker wire
try some basic shorties
If you still aint happy try a vintage pair or later Vandersteen 2 series that have a faster response in phase mid range and have a blast.
Cheers Johnnyr