And of course the possibility of fixing the small defects that almost all speakers have in the higher frequencies, that too has a pervasive and fundamental impact. In fact, the adjustment of the speaker to be flawless above the bass—from say 500Hz on up—has to my ears a more significant impact in musical terms than the exact details of bass. Getting the overall balance of the bass correct is really significant, too, but the perfection of the mids on up is the heart of audio.
Put these things all together, and a properly EQ’d system sets new standards. It is just not possible to get this level of fidelity from an uncorrected analog speaker/room combination. Very occasionally one might find a fortunate combination of room and speaker that gets close. But there is always a little bit to correct, and usually there is a whole lot to correct. And the musical impact is profound.
Moreover, there is a great increase in the perception of the space of the original venue, where the recording was made. Perhaps this is not surprising—the resonances of one’s own listening room can only obscure the acoustic signature of the recording’s venue. But the extent to which this is true may come as a surprise. It is not hard to take your room out of the listening impression in the higher frequencies. In a well-damped listening room, sitting relatively close to the speakers will do the job. But to get rid of the bass signature of your room requires something more. When this is done by removing the effects of your listening room’s irregularities, the sense of original space is greatly enhanced. (Ironic, is it not, that early high end, for which this recovery of space was a primary goal, turned its back on the most effective way of accomplishing it?)
And finally, I need to mention the marvelous advantage, especially for those toppy and often bass-shy Golden Oldies from the early days of stereo, of having effective and easily operated tone controls of the “tilt” variety, supplied in the Quicktone feature. Not a cure-all for the odder aspects of unbalanced recordings, they are, even so, a great help in moving the unbalanced into the listenable category.
History and Analog EQ: A Cautionary Tale
High-end audio decided early on to give EQ, necessarily analog as it was then, a miss. There were a few exceptions, conspicuous among them Mark Levinson’s Cello units and Dave Wilson’s EQ device included in his WAMM system. But few of the early high-end critics seemed to realize that EQ properly used was a priceless tool in audio. Part of the reason for the opposition to EQ was a lack of understanding of how it works, in particular a lot of nonsensical pontificating about how it messed up phase— when in fact minimum-phase EQ’ing to flat tends to improve phase behavior in most situations. But in addition, there seems to have been a sort of audio analog of General Jack D. Ripper of Dr. Strangelove, a kind of mad obsession with signal purity for its own sake. Never mind that the RCAs, Mercurys, Deccas, and Columbias worshipped by those same people were heavily EQed, that speaker crossovers are EQ devices by nature, and that vinyl records are EQ’d and inverse EQ’d by nature. Never mind any of that. EQ was supposed to be evil!
In view of this, it is worth noting that a surprising amount of the benefit of DSP EQ is actually obtainable by a careful use of analog EQ, even of the 1/3-octave “slider” variety that was so held in contempt by high-enders in the early days. The logic of 1/3 octave was that it is the “critical bandwidth” of the ear, the bandwidth over which the ear lumps amplitude perception together (not of course pitch but overall amplitude impression). And with a reasonable good speaker placement, one can do a surprisingly good job of correcting bass. And with a smooth speaker of correcting higher frequencies, too.
Why bring this up here? It is not because DSP EQ is not better—it is better. But, and here is the cautionary tale, if you eschew digital EQ as people formerly did analog EQ then you are going to repeat the errors of decades ago. Just as the way that for decades high-enders were mostly listening to bass that was really wrong—and higher frequencies that were not always so good either—you are going to be stuck with things that do not really work, with sound that is not really right. As to fixing bass by changing amps or cables or the like—a little experience with the DualCore will reveal the truth about that. (Imagine trying to find an amp/cable combination that will pull down a peak at 120Hz specifically!)
Back to the DualCore
The DualCore is not as automated or as elegant looking as some of its (stand-alone) competition. One can only adjust top end by the tilt controls and the parametric EQ, which takes a little patience. And one needs to tweak the bass level for ideal matching with frequencies further up. User control is good since the models of what one hears in automatic systems are never quite perfect. But, in any case, in various ways you have to do a little work at the beginning. Quite aside from the final results being good, the experimenting itself is interesting, though you have indeed to do quite a lot of it to get the best possible results. However, in the end you can get truly remarkable sound out of a system corrected and adjusted with a DualCore. One thinks of the introduction to The Three-Penny Opera: “Conceived with a splendor that only a beggar could imagine and ….so cheap that even a beggar could afford it.” Well, not quite that cheap. But still a wild bargain, and a sonic wonder.
SPECS & PRICING
Device type: Digital signal processor/digital-to-analog converter/digital preamp
Connections: Two RCA inputs,two XLR inputs, two RCA outputs, two XLR outputs, one TosLink S/PDIF digital input, one TosLink S/PDIF digital output
Digital processing: 40-bit, 2-channels
ADC: 6.144MHz oversampling dual per channel
DAC: 6.144MHz oversampling dual per channel, local clocking, buffering
Dynamic range: > 108dB
Volume control steps: 0.5dB
Input sensitivity: XLR, 1.35/2.60V RMS; RCA, 1.65/3.25V RMS
Output voltage: RCA, 1.65V RMS; XLR, 3.25V RMS
Dimensions: 236 x 55 x 146mm
Simplifiaudio (U.S. Distributor)
5415 Clairemont Mesa Blvd. #1001
San Diego, CA 92117