Five Things That Almost NOTHING Else Can Do...
...From one tiny box:
1) Achieve a perfect mix from EITHER of these two combinations:
a) Two mics, (48v Phantom or not) plus a replay unit, plus a line level source from its rear XLF socket, or
b) Any instrument pickup, (no DI box needed) plus one mic, (48v or not) plus a replay unit, plus a line level source from its rear XLF ... and then...
2) Accurately MONITOR that mix prior to passing it on, hum free, (at either mic or line level) to another speaker or an FOH console.
3) Sit atop its supplied non-twist spigot attached to an On Stage Stands Posi-Lok mini boom (MSA9502 for a mic stand, or MSA9508 for clamping to almost anything else) to achieve perfect monitoring ...in exactly the right place, ...from exactly the right angle, ...with virtually NO footprint.
4) Fill a small to medium-sized venue with crystal clear, coherent sound from something roughly the size of a shoe box, that only weighs about the same as a six-pack.
5) Save the world.
...OK, ...so (just possibly) the fifth may be a slight exaggeration...
...And I heartily advise AGAINST Mackie's suggestion of using their flimsy, short, dual-threaded pipe adapter to place this speaker in the "middle" of the boom stand that's holding a vocal mic above the SRM150.
In my experience, that simply does not work.
I have, however, successfully HUNG an SRM150 from an On Stage Stands MSA 9508 carefully (but securely) screwed into the Mackie's plastic top thread.
So, on what have I based the more reasonable four of my assertions?
I own two SRM150's that travel as a kit in a diced-foam lined Gator Utility case that also houses their IEC mains leads, a pair of pre-angled Posi-Lok Mini Booms (with Mackie's supplied non-twist spigots attached) and assorted adapter cables.
Have done for six months.
Lethal force will be required should anyone wish to deprive me of them.