I have Ayre as well....when I use the balanced operation, there is a definite improvement in the sound. If you don't use the differentially balanced circuit, you're effectively not using 1/2 of the amp. You can call Gary at Ayre who is a very nice guy and will answer your questions
Audible Illusions 3A phonostage with Ayre KX-5 Twenty
This may seem crazy, but I'd like to try a tube phonostage with my Ayre KX-5/VX-5 Twenty preamp/amp, and wonder if the phonostage of an Audible Illusions Modulus 3A preamp might be suitable. The 3A has no balanced output. Its output is 1.5V; the Ayre can accept 8V. But the AI output impedance is 1.2 kΩ; the Ayre input is 1MΩ. Is that a problem?