which is better? Stereo Amp or Monoblocks?

Mono blocks proved best for me 

I had a chance to buy two spectron  fully speced out amps to drive a pair of ML  CLX that required a lot of voltage at higher frequencies -  I bought the first one to evaluate the performance and ran it on stereo for a few months  - the previous owner said he would hold the second one for 60 days in case I wanted it ( these were an experimental build by the manufacturer with additional components and consecutive serial numbers - so if I wanted to add a 2nd one a year later - it would not be a match)

 When I added the 2nd one in bridged mono configuration - it was one of the biggest improvements in the performance of my system I've ever experienced -  no regrets    

So with a direct comparison of the exact same amp - in stereo - vs - bridged mono - there is a huge improvement in noise floor and separation -  and even though I listen at very moderate levels - the additional power available minimizes any distortion with loud transitions -  and mounting the amps right beside each speaker has likely contributed ( at least on the coat of speaker cables ) 

bart
 

At the risk of heresy....

If I were to start from scratch tomorrow, and had the budget to do so...

All mono class D's, +/- 100 wrms.  In the thousandths in the basic specs would be nice, but I don't expect 'bleeding edge' from what is still an emerging technology IMHO...

Why D's?  I've owned 'cinderblock' mono blocks that required 'dead lifts' to move.  I like the idea of 'lightweight' power, especially since my cardiologist told me to stay away from heavy lifting....*G*

Current amp is a basically a distribution AB with 6 - 2 channel amps, any and all capable of bridging.  Run individual or from the line, each with variable level and pan.  Run from 6 drivers to 24 with any combination I care to play with....

I'm big on 'flexibility; absolute perfection, not so much.

And then there's the 2 matrix that control What and How... ;)

There is a 'regular stereo' to keep peace with the spouse....*G*  One of 2, actually...

Another data point from experience to share.

Having run a few integrated, stereo, and mono amps over the years, my best experience was with tube mono amps (Primaluna PL7), by a large margin. However, those tube amps were superior to anything else I ran, so is it the tubes, the mono, or the quality that really made my system boogie?

Fast forward a few years and kids and such have relegated the tubes to but a distant, sweet memory. I did manage to scrounge up a pair of Bel Canto Evo 200.2 bridgeable amps on the cheap since both were broken. One worked fine in stereo mode, so other was sent back to Bel Canto for a little love. The BC crew hooked me up, and I was lucky the tri-paths were still good (unobtanium now...). Swapped ’em out and sent the other back. The newly repaired unit sounded pretty much the same, not enough difference for me to notice.

It’s a pretty good amp, especially considering its 20 year old digital switching technology, but my system was dark, lifeless, and just generally not even close to my old mono tubes. Frustrating since the rest of the system is more or less the same.

Yesterday I got the second one back, and was like a kid in the candy store, excited to see what was waiting for me. I turned it on low and sat at my desk, not wanting to listen too much for an hour or two while the one channel warmed up from its deep slumber.

Well, I didn’t have to wait that long. After about 5 minutes my listening room began to fill with the punch I remembered from my mono days. Even at a low listening level the sound was ’jumping’ out of the speakers. Okay, time to listen.

Its hard to describe, but that effortless sound that could seemingly come from cutting the mass of the moving components in the speaker in half emanated forth like a freight train of power. Heavy metal saturated the room with concussive power, yet delicate music sprang forth from the blackness with a new found resolution, especially at lower volumes.

Paired with LS50s the stereo amp was always a pretty good at imaging, but the pair of monos noticeably sharpened up the edges, and made it easier to hear the difference between a natural soundstage and artificial stereo effects.

The character of the sound did not change when switching to mono. However the difference in presentation was dramatic. I really can’t explain it better than saying it felt like a dramatic increase in dynamic range.

Doubling power helps, of course, but my tube monos at half the power had it too...so I think its more than just a simple wattage number.

With my tube monos, I had feeling mono made a difference. But now that I’ve experienced back to back with similar equipment, I have no doubt. Mono amps just give a dramatically better presentation.