Best Power Amplifier ??

[SKY1950]

Hi All, can anyone recommend a power amp for a new pair of ATC SCM 40 passive speakers, currently using a Linn 4100 Power Amp Bi Wired, Linn DSM 3 for streaming, Roksan K3 cd player, Budget around £1500 any advice would be welcome.
Steve

[AlastairH]

Hello Steve,

Aside from using an ATC one (the P1 does come up for sale used in your range) I’d consider something with a high damping factor.

Personally I’d also consider 150w too however this for me is down to liking headroom as opposed to needing lots of watts for every listening session. Room size, listening volume, taste in music all have an impact here IMHO.

I’ve used an old Audiolab 8000P into ATC SCM20SLPs, this was fine, yet only (!) 100w.

The ATCs are generally a consistent 8 ohm load but if you read around you’ll likely see many commenting on lots of watts and current capability to get the most out of them.

If I were looking to run my 20s as mains (they are rears in my set up) I would likely be looking at the likes of;

Quads (909/QSP/QMP etc)
Meridian 557
AVI S2000 mono blocks
Krell KaV 2250

Right now I am using a Behringer A800 class D to drive my 20s. I’ve briefly used this set up as mains (they are my rears) and it sounds fine to me. Cheap as chips too, I was running Quad QMPs but decided this was very wasteful (260w mono blocks) and needed a slim single amplifier to sit behind the sofa.

I’d highly highly recommend you beg / borrow any new amp before committing to displace the Linn.

I hope you are enjoying the 40s as they are now in the system?

Alastair

[Mariner]

Hi Steve,
I use a McIntosh MC7106 for my front ( SCM20/C1C).
Because you can bridge the six channels, you have 3 channels with 320W/8Ohm power, which is enough to feed the ATC´s.
In your case you can choose, if you want, to tri-amp or use different variations.
The MC7106 is not very high rated in the Mcintosh scene because he had no meters.
It comes from a time when a japanese company bought McIntosh, and thought that "running lights" are what people want.
But not the McIntosh fan scene. So , if you are able to find one, they are cheap!
Don´t worry.. you can dimm the running lights, so that they are unvisible.

[jophill]

Hi All, can anyone recommend a power amp for a new pair of ATC SCM 40 passive speakers, currently using a Linn 4100 Power Amp Bi Wired, Linn DSM 3 for streaming, Roksan K3 cd player, Budget around £1500 any advice would be welcome.

No specific recommendation here but instead what I would look out for.

Power rating: The active version of the SCM40 has a 150 W bass power amplifier; but this benefits from the absence of some loss from a passive crossover. In the passive version, approximately the same capability is achieved from a power amplifier rated at 200 W (into 8 Ohms). In practice you may not need to go that far but it's a good benchmark. I don't play my music very loud but like AlastairH I am a fan of making sure there's enough headroom to reproduce occasional musical peaks that are very short but can be way above average music level. I think your Linn 4100 will do a nominal power level of 50 W per channel which should actually be perfectly OK almost all of the time but it will not drive the SCM40 to its full capabilities. If you do decide to change then I would not think of power output much less than 150 W.

Current capability: Even though they are rather insensitive and need higher than usual headline power, the passive SCM40 has a rather benign impedance curve. It only drops to a fraction under 6 Ohms and that's really good for a modern loudspeaker. Any amplifier which approximately doubles its 8-Ohm power into 4 Ohms should work very well. The Quad 909 as mentioned above falls into that category. Krell-like behaviour (power doubling again into 2 Ohms and once more into 1 Ohm) won't hurt but may not be necessary.

[SKY1950]

Hi All,
First thanks for the excellent advice, I did not think speakers/amp power was so complex ! Roksan K3 is 140 W into 8 Ohms and given I'm very pleased with the K3 CD player I wonder how this amp would partner the SCM 40s ? however I would have a demo with any amplifier on my shortlist first.

Steve