Spectral DMC 12, 20 or 30 preamp?

My next upgrade is a spectral preamp. The DMC - 12 sounds very nice in my system (Thiel 1.6, Mcormack dna 0.5 or Golden tube se 40 (I swap these alot), arcam alpha 7 cd (will be upgrading soon, maybe to a rotel), MIT cable).

The DMC 20 used is more money, as is the 30. I'm wondering if anyone can expand on the sonic differences are between these? One of my priorities is bass - midbass, thiels have nothing in the low end, but the midbass is very nice on them. The less money I spend on this, the more is available to a power amp. Flip side is I'll be living with this for awhile, so the better I have, the happier I'll be.
I think the 20 has split passive RIAA, and better pcbs, but otherwise is pretty much a DMC 12 behind the scenes.Maybe a few other changes in the implementation details.

I've never even seen a DMC 30, and this probably post dates Damien Martin's design work and participation in Spectral, so I don't have a clue what is going on inside it.

All the Spectal preamps, imho, are very clean, but subjectively a little "thin" sounding. I'm not sure why that is, but it is not likely a simple thing to explain. For better bass out of your system, it would be good if the speaker was able to be bi/tri amped, in which case you could select an amplifier which might subjectively be "fatter" on the bottom end and solve the problem that way (or even apply some EQ, gasp!).
Bear, have you ever seen the insides of a Spectral ? I know that this may sound "insane" to some people ( especially at this price level ), but do they use ribbon cable in any of their designs ? As to their sonics, i would agree with your assessment i.e. very fast and clean but lacking in warmth and body. Sean
Bear and Sean: Any warmth or body that you perceive is in fact a euphonic distortion. Once you listen to Spectral day in and day out you will not go back to any other electronics. But you need a revealing source to get their best performance, a Rotel or Arcam will not cut it. The Thiels although a great value, will not benefit enough the outlay for any Spectral product. Spectral might not be a good choice for you. I personally like the NAD Silver series, it would make an excellent alternative, and far cheaper!!!
A Spectral DMC-30S just replaced a Sonic Frontiers Line 3 preamp in my system. I would *not* at all characterize the sound of the DMC-30S as "thin" or "lacking body". In fact, I find that it does a great job of giving a sense of weight to the music. Bass performance is also quite a bit better than it was with the Line 3. I'd say that all aspects of bass performance have improved.

The most striking difference though between the two preamps was that the Spectral seemed to remove layers of noise. I hadn't realized how much noise had been present with the Line 3 until it was gone.

IMHO, the DMC-30S is an amazing product.
Is the split passive RIAA a phono only concern?

I've listened to the DMC 12 vs the ARC LS3 and the Purest Sound systems in my system, and the DMC 12 is a big improvement, even with the Arcam front end. Bass has more impact and control, more detail comes through, dynamics are better, and the fatigue factor is reduced. Soundstage is bigger, too and the Overall balance is improved. That's the reason I want to go with the Spectral pre amp. Question is, does the additional cost for a 20 justify performance difference? According to Bear, I shouldn't really expect much change. By the way, what kind of digital front end would you recommend?


Hi Robert,

If it is going to cost anything in the area of $2,500.00 I'd forget the Spectral and find a used NYAL Minuet in A, send it to Stephen Sank, and be perpared for a 6 to 8 month wait while he works some serious magic on it.... I have heard Spectral with the Thiel 1.6's, using a GCD-750, and while it is impressive, Sank's moded Minuets sound like Spectral's on steroids due to the 6DJ8 tubes! Spectral WITH warmth, bass, everything. Just do not let him use anything but the standard case for the preamp. He'll make up a seperate power supply which is fine, but my Minuet is now in a wooden box, not it's metal case, which I would have prefered!

Remember, my advice is worth every penny you paid for it! :-)

The day that Spectral gear sounded "whitish" (HP of TAS) and thin are long over. To my ears and mind, Shubertmaniac, is absolutely right. As far as I can see,Robert, in your system the DMC 12 would be just fine. However, one day you might wish to upgrade DC-player, amp and/or speakers and would be happy to own a DMC 20, which in its Mark II version has a far deeper layering of the soundstage and is without that tad of grain, the DMC 12 still had on my Quads. Bass with the DMC 20 is incredibly clean, fast and punchy. I'm sure you would like it. Cheers,
The *difference* between the DMC 12 and the DMC 20 *is* the split passive RIAA *and* a change in the board layout and materials... iirc the 20 used a foamed polypropylene pcb material. The gain stages were otherwise identical.

Neither of them used any ribbon connectors.

As I mentioned I have no idea what is in the DMC 30, and no idea what if anything they have done to these models in any newer versions.

All of them are very clean, and low distortion designs. Imho, far better than a majority of solid state preamps.

Robertd made a comment in which he somehow misinterpreted what I wrote earlier. "...According to Bear, I shouldn't really expect much change." I'm not sure what he was thinking about, but I don't think that's what I was talking about.

Anyhow, if I had to own a commercial solid state preamp, Spectral's would be on my list.They are clearly a step or two up from the average stuff being sold.
Bear, it is both pretty funny and amazing how using the exact same parts but in a different layout on a board can get you very different results, isn't it ? Since i work with RF for a living, which can be EXREMELY layout sensitive due to impedance changes and circuit stability, i found this out a LONG time ago. I don't think that most audio designers / engineers pay attention to such things. In my opinion this could be the difference between a good product and a TRULY great one. Sean
While we are on this subject, I'd like to raise the question again of whether anyone has directly compared the dmc20 vs. the dmc30S or dmc30sl. I haven't done so, and would like to hear the opinions of others.

Thanks. (It's still on topic.)
Yeah Sean, layout does matter as soon as you care about a bandwidth beyond a few hundred kHz. That is one of the things that set Spectral's design off from some others. In fact there is/was a PS Audio preamp that more or less borrowed the same circuit (really, really close) but did not sound worth a damn, imho. Although it may have been one of the better PS Audio units. The layout just was not up to the same standards...side by side the PS looked like a clusterknot compared to the Spectral.

Take a look at the Halcro amp, they had to pay attention to RF layout as well... (not for raw bandwidth, but to keep wide bandwidth so that the feedback would work to drop the distortion 2 orders of magnitude lower than usual).

Out of curiousity, do your comments on split RIAA and pcb's relate to the dmc 20 series I or series II? I thought the series II, at least, was a Keith Johnson design and not Demian Martin's.