Review: Spectral DMC-30SL


Category: Preamps

The Spectral DMC-30SL is not for everyone.
Unless you have very revealing speakers
with excellent transient response and
a very high resolution CD player with
balanced topology, then you will be pulling
your hair out with this one. And not to have
the very best cabling going, you will not
get the best out of this beast. However, if
you do have the above prerequisites then you
are in for a treat. The soundstage is now
wall to wall and deep, the images are absolutely
rock solid. Not the least bit grainy nor any high
frequency fatigue. It has the typical liquid
sound of Spectral. However its coup de main
is its unprecedented low level resolution.
Whatever is on a cd WILL be transmitted to
the speakers and I mean everything. A foot
tapping, a very light slap on the body of
of a cello, and much to my chagrin the grunge
of digital audio. The Resolution CD50, in its
day was a fine CD player, not now!! Every
imperfection shines through and is magnified;
its like looking through a microscope. Cabling
is sometimes an important issue with Spectral,
in particular, their amplifiers, but now with
their preamplifier too. Just changing interconnects,
will alter the character of the soundstage and
imaging. It looks like until I have the finest
interconnects, this preamplifier has not reached
its highest level of performance. And until I
upgrade the CD playback system, this system will
play music and play digital grunge, too.
So do I recommend this preamplifer, only if
are willing to go the extra mile and ensure the system
has the finest interconnects, speakers, and cd
playback system. Then it will be a keeper for
a very long time. Reference quality for a reference
musical system.
shubertmaniac
Bombaywalla: I started out with an ARC SP8 and ARC D115.2 with the Acoustat 2+2 and enjoyed the system for years. I also had a DMC10 and a pair of DMA50s also. I would mix and match various combos to see which would work. However about three years ago (place blame on Audiogon!) I got worked up about buying a new system, I was in near sticker shock at first, but also because of Audiogon I was fortunate enough to put together a very decent system. The center piece of the electronics was the DMC30sl. I think it serves its purpose quite well. In regards to the ARC preamps, I still like them, in particular their very seductive midrange, and upper bass regions. Everybody seems to think that ss preamps
get shrill in the treble region or at least grainy. In most cases they are correct in that assumption, however, the Spectral seems to be lacking in this aspect; it is smooth all the way to the top of the frequency range. I just think in general it is harder to make a very good ss preamp( ditto ss amps) than tube (pre)amps. I have no plans to change or get up tight about my system with a ss preamp or ss amp. I just enjoy it for what it is: a window to sound reproduction.
Shubertmaniac,

Thanks for the feedback. You are right - all this expensive gear is a window into sound reproduction, which is hopefully getting us closer to a real-life event. Good to read that you're enjoying the music. That's the spirit!

BTW, I hear that the DMC-30SL is a 1-box pre that costs more than the DMC-20 2-box pre! I thought that Spectral finally got it right in keeping the power supply out of the pre electronics! With the DMC-30 they are back to a 1-box pre, which should have continued to be a 2-box pre, IMHO. It would seem to me that, even tho the DMC-20 is older, I'd pay to get a 2-box pre than a 1-box pre. What am I missing here?
You would be missing the ~ 8 dB better SNR of the dmc30 series over the dmc20's. I haven't taken a dmc30sl apart to analyze the power system but the manual states that the internal transformer is designed with a wider than normal separation between the input and output transformer windings to decouple the input to output noise transfer.

I've owned several of these preamps and heard all of both series. The dmc30sl is superior to the dmc20 series in every way.
The preamp is passively shielded with nu metal. It helps eliminate stray magnetic fields. If you ever have an MRI done, with their tremendously high stray magnetic fields, the walls, floor, and ceiling have some kind of passive shielding, usually something other than iron because of saturation effects; nu metal is one type. Of course one way around this is by having an actively shielded magnet system, which is now becoming more common, expensive but much better than passive shielding.
I heard the Spectral DMC-30SL in my system at home (while I was waiting for the Spectral 4000 CD player to arrive) on much cheaper Primare CD player. Other components: CAT Ultimate preamplifier, MIT oracle V3.1 cabling between CD player and pre amp, a cheap cable between pre and power amp, Spectral 250 power amp, MIT oracle speaker cable and Avalon Eidolons. With the Primare CD player and the cheap cable between pre and power amp the CAT is winner: the sound of the Spectral 30SL is a little bit too thin in the midrange. You will hear the superiority of the 30SL (more details, more speed, more slam) but the result is not very musical.
Now the Spectral 4000 had arrived and with an MIT cable between pre- and power amp the result with a 30SL will be much more musical.
So I agree that cabling (also the power cords) are very very important for the Spectral 30SL to show its superiority. I also agree that both the CAT and the Spectral have the same overall balance with somewhat less focussing power of the CAT: the space/stage is filled more with the CAT. The CAT is fuller in the midbas but doesn't have much bloom for a tube preamp.

As I live in the Netherlands I am afraid that the price here of Spectral gear is somewhat high especially considering the weak Dollar : Euro ratio. What is the price of the Spectral 30SL in the USA?