Hi Xi-Trum,
No issue at all, MB-100s -and- PT-2s have no DC offset to worry about. MB-100s/ PT-2s average less than 0.002 VDC (2 mVDC) offset during IRD factory testing.
Everyone going active should just take a moment to make sure their gear is working correctly since the protective passive crossovers which normally protects the tweeters (with a cap) will be removed and the drivers will be connected directly to the power amplifiers.
Since tweeters don’t like DC I usually just do a quick test on the MB-100 input ICs (in mid air not connected) going to the MB-100s, with a multimeter, just to be safe. Being careful especially with DIY or mid-fi upstream gear.
I test in each source position (preamp volume control set to max) with each source playing during the test just to be sure I get no unwanted surprises down the road.
Don’t forget to “turn the volume back down” and “turn everything off” before reconnecting the ICs to the MB-100s or you could hurt your speakers!
You need to remember that DC coupled high-end gear, even with no DC offset of it's own, sometimes will "pass through" any DC that comes into it's inputs.
The PT-2 has a servo that controls DC but the upstream components, source and preamp, should still be DC free. Normally DC will not pass through the PT-2 for longer than a second or so before it’s cancelled out.
The MB-100 has no DC gain so if 3-10 mVDC comes in from upstream only 3-10 mVDC goes out which is really no big deal.
DC offset can cause damage when it gets up to 50-100 mVDC. At about 100 mVDC it will start to damage tweeters. FYI woofers are not as bothered by DC and can easily handle several volts for extended periods causing no damage.
DC problems are quite rare with correctly designed gear that is operating at MFG specs. Many people talk about DC offset but, very few ever have problems. Usually only defective equipment will have DC problems, very rare with good high-end gear.
I hope this puts your mind at ease. Thank you for your interest.
