Driving MBL 121: Accuphase or Gryphon

A lot of it depends on how hard you want to drive the 121's. At high SPL's, the 121's sound shrieky and congested, the soundstage collapses especially with orchestral music and opera, if driven with inadequate power. With the Plinius and X250.5, it is quite likely you are not driving the speakers too hard. If your listening levels are moderate, then these amps should be good enough for the 121's. But the 121's need to be cranked up to reach their full potential, for optimal soundstaging and airiness, midrange richness and instrumental bloom. Otherwise, they sound a bit dark.

I now have the 121's mated with the 350.5. Just an amazing soundstage. Very dynamic down to the 50Hz region. I feel you need a pair of subs with these. We have one so I get a bit of off channel balance.

With the Pass X350.5 no strain noted what-so-ever and completely at ease. I would expect that with a 150 lb amp.

Last night we watch a movie through the 121's. Note I have a single JL Audio Fathon F113 doing base duties (I'll add a second one later). OMFG. I didn't really realize or even think about these speakers in a HT context but they made me think of it! These speakers are more incredible than my line arrays and my line arrays are unbelievable in HT. I could see no reason to have surround sound with the MBL's IMHO. They seem to produce surround sound all by their little selves.

I use my MBL 111e's in an integrated Home theater/two channel music set up; and power them with the Bryston 28sst's monoblocks; much better dynamics and sound now with this extra power; then when I was using the MBL 8011's; which I thought underpowered the speakers...for theater; I use an Aerial CC5 center speaker; as I thought it would be difficult to get proper dialogue with an omni speaker for center channel duties; and it integrates great....sounds like you are on the right path; I have one Velodyne DD15 as a sub; but the MBL 111's have their own woofers; so I don't need as much extra base as you will.
Enjoy; and let us know how you solve these issues...

Bob,

Wow! I wish I can afford your system. The quest for the absolute sound continues. Just curious, what do you use for your music source, digital or analog? I am not into analog because of the extra hassle. But the current digital state-of-the-art comes rather close to analog nowadays.

I use digital...I have a Meridian G-98 running thru the hd621 switch, which conveys some of the new aphodizing filtering; which makes my CD's sound much better, then back thru into a Meridian 861 v4.2. I also have Qsonix music server running digital out into the 861; the new hi resolution 24/96kz downloads from HD tracks played thru the Qsonix is actually better quality than red book cd as described above; but standard cd's thru the qsonix is just a slight step back from the g-98/hd621 sound..but it's all good. I also use the sony 5000es for Blue ray discs and home theater; the BD player handles the new HD audio info; and it gets run into the hd621 switcher; then into the Meridian 861 processor for awesome hd audio quality thru 5.1 speakers...I've not tried analog with my digital Meridian gear..it converts all signals into the digital domain anyway; but it also lacks a two channel audio bypass; so I can't get benefit from external dacs...

Other MBL owners have switched to the Bryston amps; see Dev's posts; with good results; and less expense than using MBL amps..the Bryston 14's or 7's might be a good match; but it seems that you found great synergy with the Pass 350.5...in an apartment; you seem to have your system now dialed in pretty well...