Currently using a peavey head with a tube preamp and a schecter bass with emg HZ's. I think the combo is a bit too warm and ends up sounding muddy with overdrive/distortion. Would active emg's be a good choice to get rid of the overly warm tone? I was thinking about going emg35p and emg 35j combo. I play metal/punk.
How about playing with the EQ and backing off the bass on the amp? Also, a change of strings makes a big difference. Chances are you can make any needed adjustments between those two. Pickups are the very last thing I would change.
Yes, active EMG's sound less muddy and more clear than the HZ's, IMHO. I use the regular P and J, but if you REALLY want some treble, the PX and JX are what you want. Personally, the regular PJ set is enough treble for me, but YMMV. The PX and JX also come in a 35 soapbar. BQC 4-knob preamp is also highly recommended with their actives, or the BQS if your bass has 5 knobs.