My old MS-60's have internal stereo speakers and amplifiers, which adds a lot of weight. So does the SD-5. When I bought the MS-60's, there was a non amplified option (MS-50, I think), which would have worked fine for me and been a lot lighter.
The SD-5 does not have the non speaker option. That would probably cut 15-20 pounds off the weight, which would be nice. Most of my jobs are set by my crew, so it really isn't a big deal for me.
R.
Russ