This review is actually about the Chord SPM600 power amp,a slightly more powerful version of the SPM400.
When a friend of mine bought himself Chord pre and power amps (SPM1200),I just had to get myself a pair(after one listen)
I couldn't afford the SPM 1200,so got the entry level CPA2200 pre,and the SPM600 power amp.
The amps are superbly built from aerospace grade aluminium,are well finished with excellent attention to detail,and mine look gorgeous with the optional integra legs.They can be operated remotely from the included remote control,which is hewn from a solid bar of aluminium.
The power amp utilises a switch mode power supply,which rectifies AC into DC and then switched to 80khz before final filtering,so a hefty transformer is not needed,and any mains noise is switched upto 80 khz,well out of the audio band.
Enough technobabble,how does it sound?In a word,stunning.Firstly I noticed a clean,open,airy sound,and the character of the sound doesn't change when the volume is turned up,just louder.Soundstage and imaging are superb,bass slam and attack are very quick.These amps to my ears are very neutral,passing through whatever signal the source feeds it.
I built my system around these amps,front end are Meridian 588 cd (stunning see separate review),Michell gyrodeck.I recently upgraded speakers from B&W cdm7nt (good) to Nautilus 803 (different league).I also purchased a PS audio 300 power plant,which I use to power pre amp,cd,T/Table,phono amp,and its power supply,the power amp is plugged into wall socket as it consumes too much power for the P300.I read in one of the hifi mags,that due to the nature of the switch mode supply,they can produce mains noise,and that the cd player they tested it with,didn't sing,until they ran the cd through a mains regenerator,to isolate it from any noise from the mains.I too have found this,and now the Meridian 588 really does shine,almost like a veil has been lifted,female voices in particular are so realistic,I'd swear they were in the room performing just for me!
I also had cause to praise the protection circiutry in the power amp a few days ago,I'd just got home a power supply for the phono amp,plugged it all in,turned them on,and instantly the power amp tripped,I tried a few different settings on the phono amp to no avail,the amp kept tripping on selecting phono,thereby protecting the speakers from damage,I took the suspect phono supply back to dealers where it was shown to be puuting out far too many volts.Thanks to Chords protection circuits,they probably saved my new Nautilus 803's from expensive damage.
An excellent amplifier that casts a transparent window over the rest of the system. The dynamics are very good and the whole sound is effortless. The ultra fast nature of the amp does mean that it could sound harsh to some, especially if partnered with speakers with an over emphasised treble. The imaging is solid but not quite the best, though my pre-amp is most likely to blame, as i've heard the amplifier with other equipment sound better in this regard. Overall? A revealing and stable platform for the music, and one that has the side-effect of showing up any flaws in the playback system. It's lack of what some people call 'emotion' that apparantly other amplifiers have is it's greatest virtue - It allows the music to speak for itself, without prejudiced.
The Chord SPM 400 actually retails for about $2500, not the $6000+ listed on this site. I bought one used for $1200 and have actually been knocked out by the sound. Metaphorically, of course, although this amp gives me the impression that with sensitive enough speakers, it could physically knock you out.
The SPM 400 is the 100W /channel "baby" of the Chord line of ultra high-end amps. Chord was one of the first manufacturers to produce an amp with a high-frequency digital power supply, which now other manufacurers have employed, for example, the Linn Klimax, or Bel Canto amplifiers. They also employ some specially-matched MOSFETS in the output stage.
The result is that the sound is powerful and effortless. This amp is very revealing and when paired with good equipment, and just sounds magnificent. I've changed interconnects and speaker cables a lot over the month that I've been living with this amp and have heard everything from a bright sound, to a dark sound, to having the cymbals right in my face, to having everything placed back at some depth in the soundstage just where it should be, and so on.
The other amps I compared it to all cost from $4000-$10,000. While I wouldn't say the SPM 400 "bested" any of these amps, I do think it held it's own! The comparisons were definitely valid, and I haven't regretted my purchase for a second.
So I would say the SPM 400 is powerful and wonderfully transparent, in that it doesn't add any overriding sonic quality of it's own. It is also fast and exciting, and if the associated equipment and the recording dictate it, it will slap the speakers into submission and make them boogie, chirp, howl, bump, grind, and/or sing as needed.
I would highly recommend this amp. If you have the money, check out the upper range amps in the Chord line. They look like they're built like a battleship, but just landed from outer space. By the way, Chord is a British company that is known for their professional amps that are used in recording studios including Abbey Road and throughout the world. They recently hooked up with a distributor in the US for their home gear, so hopefully we'll be hearing more from them.
Arcam CD72 CD player Cary SLP-94 pre-amp (w/ Bugle Boy 12AU7A tubes) Chord SPM 400 JM Lab Chorus 706 speakers Various interconnects and speakers cables as mentioned above