Joseph audio perspectives, magico a3, ATC scm40 v2

I was considering getting the ATC p2 amp and pair with ATC scm40 v2. How do you feel this p2+atc40 passives would stack up against the atc40a? The atc40a is a bit pricer than the passives combo though.. Since I can only find new ones of them which is $13k a pair.

@yuhengdu_tiger Good to know you've already compared the SCM19A and preferred your SCM40s. That's significant! So again we figure that SCM40As would be the ideal solution for your room but I completely empathize they are so expensive new, and finding used/demo pairs is almost impossible.The P1/P2/SIA2-150 are all perfect matches for the passives, but they can't match the full performance of an active tri-amped pair. But recall also that there is the option of passive biamping and triamping.

Very crudely, and with some margin of error, let's figure that: 

• SCM40A = 100% sound potential (active triamp)
• SCM40v1 + P1 = 65% (passive stereo)
• SCM40v1 + P2 = 75% (passive stereo)
• SCM40v1 + 2 x P1 (passive biamp) = 80%
• SCM40v1 + 3 x P1 (passive triamp) = 85%
• SCM40v1 + 2 x P2 (passive biamp) = 90%
• SCM40v1 + 3 x P2 (passive triamp) = 95%

If we consider the cost of each config, we hit irrational returns with passive triamping, as we exceed the cost of the SCM40A itself, but there are some interesting options before that. 

The amp ratings for each SCM40A are: 150w for the bass driver, 60w for the midrange, 32w for the tweeter. Which would let you play at higher listening levels than you wrote that you ever do. So let's call that 100% performance is also an overkill.

I suggested before you may get really good improvements in clarity and poise from passive biamping (one amp per speaker; one output dedicated to the bass terminals + remove the bass-mid jumper, the other amp outut goes to the mids or tweeter terminals + keep the mid-tweeter jumper). 

Is there any way you can try this out? It doesn't necessarily need to be ATC amps, even though they are proven matches technically and sonically; there are going to be many great amp matches out there. You'd need two stereo power amps with the same gain (thus easier to do if they're identical). Compare the difference using one of the amps for both speakers, vs one amp per speaker, and one amp channel each for the bass terminals.

P.S. The pro audio versions of the P1 and P2 (same inside as the consumer ones!) can be bought new from pro audio stores much cheaper than from hi fi stores, weirdly.

Well I have done that!  I have tried every combo of passive with ATC amps (which is not so difficult when you are the importer).  The active wins every time on the same issues: detail, image, transparency, dynamics.   I've even done that demo at a trade show, AXPONA 2 years ago.   Its not hard to hear. 

BY the way, no apparent improvement in detail, image or transparency adding amps in the passive biamp or triamp method.  Some improvements in dynamics due to increased power.  But imaging is what I like out of actives and there is nothing I can do to the passives to equal the actives in listening, consumer or pro.

To be fair there are some people who will not be able to hear the difference.  It is NOT like two different speakers.  The timbre, the balance and the "tone" of the speaker was the same between active and passive.  Just the resolution, the quality of the image, the overall speed of the speaker was very different. 

I know that from a technical perspective there will be a big difference between the passive and active in the linearity of phase.  The actives will look perfect, the passives not perfect.  This is a by product of a passive crossover, all that cable, and lack of ability to adjust phase of individual drivers- all those problems go away on a active designs.

Brad

     

Fair enough, Brad. I was just trying to give the OP some options to upgrade, cause the SCM40A new cost is prohibitive, and he'd mentioned driving the passives was an issue, and they couldn't find any used actives. Maybe you could swing some other options for them!