Just an end users comment here: I own Ralph's gear and to my and my fiends ears, he has solved the "the real issues facing...(the) task of making a small signal larger" to all our great musical satisfaction. I am not familiar with the A- or whatever CAT, so I cannot form an opinion if it is really that break-through which some make it out to be. Generally however, good old Bill does not use his acid squirt gun without good reason, but what do I know. I know however, and that for certain, that in a well set up rig, volume and pitch do not have anything to do with each other. My better half and I are blessed, or cursed if you like, with a "the absolute ear", she especially would notice the tiniest aberration in pitch, in fact I use her to set up my TT and I would have noticed something like that in all those long decades of listening to music at home.