I think it is Crest Audio that makes a rackmountable 24 channel mixer. I could be wrong..it might be 16 channels.

A long time ago, I purchased a Roland 24 input, 6 effects sends, 2 pair output, rackmount keyboard mixer. It was the same size as my TASCAM DA88's and worked well as a monitor mixer. It had plenty of headphone output, with dual stereo buses. But there are other rackmount line level mixers where you can get 8 into a 1U rackmount, and have the ability to gang multiple units to a single stereo output. It would take up no more than 3U rack space, although you might be hard-pressed to find any kind of solo feature? For that, you might need to use a pre-fader effect send for solo monitor?

Simple problems require Simple Minds (as engineered by Bob Clearmountain)!
Ms. Remy Ann David

Thanks for the replies guys. I know behringer make a 1U mixer but what other brands/models are out there?! Ideally something like the Roland mixer would be cool too but i think they could be rare as these days. But yeh any other company ideas with the 1U ideas?

Cheers