I am mixing a record for some folks, sort of Elliot Smith, sort of Tom Waits, sort of Kurt Weil, and very organic. I talked em into tape for the mix and was able to find a bunch of 456 for sale here in NYC. I must admit that I have been a GP9 guy and sometimes a 499 guy and almost always a 30ips guy. I wanted to try 15 ips and told the label and client why and they asked for a comparison. I thought it was a cool idea so first we printed to PT back through AD8000, then to ATR at 30ips, then to ATR at 15ips. (I should mention that we run 15ips with IEC1 equalization.)
The 30ips sounded smoother, more relaxed, perhaps not as silky as gp9, but had good body and the music was glued up as expected. Compared to PT everyone agreed that it was nicer to listen to and sounded more "finished". Very true.
15ips? All I can say was the split second I heard 15 I was sold. Can't remember the last time I went 15 and then never to 456, but my god it is so good. If you are like me and have been a GP9/499 user give 456 a whirl when its available again and mix one to 15ips - IEC1 makes a good difference - you won't be sorry.
As for the sound, creamy, rich, big, finished, solid, and much easier to get your ears around... Someone in the control room remarked that it sounded like the sound on tape felt much closer to capturing a live performance in energy and continuity. Glad 456 will be available again. The mastering guy is going to be very happy.