There are many preamp out there with bass/treble controls. Some of the Vincents do have them. Don't know which NAD integrated you have but NAD c165Bee preamp has controls and is pretty decent. It's very detailed and neutral but some may consider that clinical and dry. I've owned one for a couple of years and like it.
Need a preamp with tone controls!
OK, most audiophiles would say I shouldn't need tone controls, but I have a good system that plays QUALITY recordings beatifully, so much that it makes me not even want to listen to many of my 70's & 80's stuff. This comprises the largest part of my collection. So I've been looking at McIntosh preamps...great tone controls/equalizers, etc. Any others out there of audiophile quality???