Integrated Amp upgrade path


I’m currently using a Macintosh MC 8900 to drive Vandersteen Treo CT’s, with a six pack of Rel S510’s, streaming only.  I understand Boulder will shortly have a software upgrade for the 866 that will include an Air Play equivalent to allow full use of most streaming services.  Looking for thoughts from anyone with experience with the 866:  how much of an an SQ improvement with this upgrade?  Incremental?  Immediately noticeable?  Thanks for any help!
cosmic_charlie
I agree with several other folks who say your sound will be very different switching out from the McIntosh. You need to hear the Bolder or other recommendations before making a switch that big. I am a former Mcintosh owner and in my case moving to another brand gave me a big improvement over the sound of the Mc. But to be clear, nothing wrong with McIntosh, it just has it's own voice. And I realized I liked other amp's sound better. You may not find that to be true.
@deadhead1000: What did you upgrade to?...just curious.


I am a MA8900 owner. I am going to try a Lumin T2 with my amp. I currently have a ~$1500 Teac NT505 which sounds much better than the MA8900’s DAC, so as to streaming I would call out the installed DAC as being inferior. That being said, you can upgrade your MA8900 with the DA2 module which gives it a much more current DAC and more capabilities.


OP, I notice you have a REL 6 pack. Currently I have 2 REL S/812s and am thinking of building up a six pack. How challenging was it to dial in the six pack?

Thanks
@hsw—Not hard at all.  I set levels and crossovers in pairs, from the bottom row up.  Crossover level is lowest for the bottom pair, second row a bit higher and third row is higher again.  Levels follow the same pattern from low to high, but are closer together.  Then after those were done, small tweaks to each row as needed.  I found the level control to be the most sensitive and it had the biggest impact, but it was not hard to match with the volume of the main speakers.  I have a small room (10 x 14), so YMMV.  Maybe an hour’s time, max. 
The line array concept was a big plunge for me, but the results are spectacular:  wider soundstage, bigger image, better clarity, and most significant to me, more heft/substance/weight (without any hint of softness) to the rendering of each note, tone, vocal, or percussion—across the whole music spectrum really, which to my ears has always been one of the hallmarks of live music.  Not a cheap upgrade by any means, but  the ROI is stunningly good. 
Thanks for the feedback!

It look me about a month to tweak my RELs. Mostly because I first went down the path of lower crossover and higher volume. The sound in my system was very clean, similar in voicing to the Revel Salon/Studio series, but that was not the aesthetic I was going for. I doubled back to try higher crossover and lower volume and I preferred the richness the higher crossover afforded.