Regarding my suggestion of a test record or CD providing 1/3 octave warble tones, Stereophile's Test CD 3 appears to be suitable (specifically tracks 17, 18, and 19), and is available here. Further description is provided here.
A possible limitation of that particular test CD, though, is that as far as I can tell it may not provide separate tones for the left and right channels. If so, and given that your Ayre integrated amp apparently does not provide a balance control, you would probably have to disconnect one speaker, or one input channel to the amp, in order to accurately assess the other speaker.
Good luck. Regards,
-- Al
A possible limitation of that particular test CD, though, is that as far as I can tell it may not provide separate tones for the left and right channels. If so, and given that your Ayre integrated amp apparently does not provide a balance control, you would probably have to disconnect one speaker, or one input channel to the amp, in order to accurately assess the other speaker.
Good luck. Regards,
-- Al