The LJM 12-2 is a discrete Class AB amp. That's a rather different animal than a Class D amp. You need an amp with good PSRR if you want good results with a switching supply.
I've used the Connex SMPS300RE, SMPS300REh, and SMPS800RE with my Modulus amps. I'm not able to measure anything SMPS-related on the output of the amp. The Modulus amps are all Class AB and have a built-in error-correction circuit that makes them very low distortion (think -120 dBc) and rather agnostic to the power supply used.
Tom
I've used the Connex SMPS300RE, SMPS300REh, and SMPS800RE with my Modulus amps. I'm not able to measure anything SMPS-related on the output of the amp. The Modulus amps are all Class AB and have a built-in error-correction circuit that makes them very low distortion (think -120 dBc) and rather agnostic to the power supply used.
Tom