I had the 88 and went to the M120's and saw a huge improvment. It just goes to show you that 2 people can do the same thing and not have the same sense of change.
I think the 88 is not a very good amp. I would switch amps first. And as soon as you can afford. Change the pre.
I think the 88 is not a very good amp. I would switch amps first. And as soon as you can afford. Change the pre.