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 you hit it right on the head. Spectral makes some killer gear IMHO and to get the most out of it you have to go the extra mile. System matching is what it is all about.
Hi Shubertmaniac,as an owner of the DMC-20s2 and DMA150 and Avalon Opus speakers I agree on your conclusion that for a highend pre-amp to show its capabilities, it requires (demands) high standards for the fron-end as well as the back-end of your system and not to forget the cables and the AC. For a broad band pre-amp as the DMC-20 any high frequency noise will effect the phase correctness (assumed it is) of the input signal and there goes the (inner) soundstage and positioning of the image. Not to mention the lost of inner detail and timbre.
A spectral component or chain requires at least a shielded (best is double or tripple shielded) AC cable from your equipment room to location where the AC comes into your house and is splitted to the various groups. In The Netherlands (where I live) the AC in an normal house has 3-phases and I use an seperate individual phase for my equipment. Although the improvement is less than by using a direct shielded AC-line. A slong as you haven't taken such measures I wonder if you will ever experience what your DMC-30 is capable of.
Good luck Henk
After 6 months of critical listening to the whole system, I replaced the DMC30SL with both a DMC10 and and an ARC SP8; switching back and forth between the two. Then the following day going back to the DMC30SL. There is just no comparison! The DMC30SL has a much larger soundstage and better control of the image, the bass impact is stronger.
But the two most breathtaking aspects of the DMC30sl is resolution and tonal balance and correctness. My favorite instrument is the cello and the Spectral preamp gets this right,from top to bottom of the musical scale;just amazing. The woodiness of the cello is not muted or plastic, just natural. But its ability to get into the CD bitstream and glean what is there is something to behold. It is enchanting. So many old CDs, become more vibrate with the ambient resolution that this preamp produces. Honestly, I cannot wait to get home and turn my system on and just get enraptured with the music. They say solid state is cold
and heartless, Spectral puts the heart and soul back in.
I couldn't agree the dmc30sl for it's ultra revealing ways, and the overall Spectral/Avalon sound for sheer musicality.
Just wanted to add another datapoint tho' not exactly related to the DMC-30SL:-

Today an audiophile friend kindly brought over his Spectral DMC-20 2-chassis preamp. We compared it to my CAT SL1 Mk3 in my system. The DMC-20 is a fantastic preamp indeed & I agree with 'Shubertmaniac' that the DMC-20 put back heart & soul into the music. This pre is very revealing & neutral. It has a musical midrange, extended highs & excellent bass. One of the many tracks we played was "Rainy Day" from John Lee Hooker's "Don't Look Back" CD. Fantastic, stomach pounding bass (not to mention excellent vocals). I had to constantly remind myself that I was listening to a ss preamp!

This, IMHO, is the highest compliment that can paid to a ss unit:- when we switched back & forth with my CAT preamp, we could not tell any difference in the sonic signature! We, of course, could see which pre was playing in the system but if we were blind-folded, no way we could tell! If I had to struggle to find a difference then I'd say that the mids of the CAT were slightly sweeter & fuller than the DMC-20. This I attribute to one being a ss design & the other a tube design. The DMC-20 was slightly lean in the midrange vs. the CAT. However, both preamps are on the accurate side of neutral. It would be fair for me to say that the CAT is the tube cousin of the DMC-20 or the DMC-20 is the ss cousin of the CAT.

Then we took the DMC-20 to my friend's house who owns a heavily modified Audio Research SP-6A. What I can tell you is that the SP-6A held up remarkably well to the DMC-20. The SP-6A has a very beautiful bloomy midrange & those of you who have owned any of the SP series preamps know what I'm talking about re. the bloomy midrange. If the DMC-20 was slightly lean in the mids vs. the CAT then it was much more lean vs. the SP-6A. At this pt. many of you must be saying that I must be smoking some sort of weed! I reassure you that I'm not & I know what I'm talking about! This SP-6A was brought up to spec. by Richard Gray & then K&K Audio upgraded the power supply caps to computer grade Panasonics & the coupling caps to Kimber. Now, this preamp will hold its ground even to a DMC-20 type pre. It is stunning to realize this & one has to hear this SP-6A to believe it.

Anyway, the DMC-20 has more extended highs & a better control of the bass but it loses the midrange hands down to the SP-6A. The owner of the SP-6A & I agreed that the DMC-20 high freq & better bass was not worth the large price differential esp. since my friend was able to get the SP-6A in stock condition for a pittance & paid a very reasonable amt. for the upgrades. We played a bunch of music - Alison Kraus "Live", Grateful Dead "American Beauty", some bluegrass music, various Jazz vinyl. The vinyl was piped out of the SP-6A from the tape-out & fed into the DMC-20 & into my friend's BelCanto SET40. When we played the vinyl, it was very diff. to ascertain the DMC-20 signature so all my comments above refer to when we switched to CD & used only the DMC-20 as the preamp.

Anyway, today was very nice day comparing preamps. I am mighty fortunate & pleased to have listened to the DMC-20 for it is one of the most musical ss preamps I have heard in a very long time. The designer has done a splendid job of giving its ss heart a lot of soul. I can see, now, how you owners enjoy its musicality. If I had to chose a ss preamp one day (I hope that day is far, far away!) then the DMC-20 would be on my very, very shortlist. Good choice guys!
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.

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?