OT: Mackie mixers and headphones

[Mark Hamburg <mark@grubmah.com>]

I love my Mackie mixers (1202 VLZ pro and 1642 VLZ pro), but their 
headphone outputs don’t seem to really be up to driving my Sennheiser HD 
380 pro headphones. The Sennheisers sound great with the Apogee Duet on my 
computer, but muddy and thin with the Mackie and checking the impedance it 
looks like they just want too much power. I’m looking for something that I 
can reasonably use when I need to have my monitors switched off for the 
benefit of those around me. So, two choices: headphone amp or alternative 
headphones. Any recommendations?

Thanks.
Mark