TESTED: Running Springs Audio Dmitri AC Power Conditioner

No Tradeoffs

Despite the increased heft in the bottom end, the presentation was faster and “lighter.” By lighter, I don’t mean less midbass warmth or weight, but rather greater emphasis on the midrange and upper-midrange, along with greater transient agility. A car analogy comes to mind; powering my system’s front end from the Dmitri was like shaving a few hundred pounds off a sports car driven spiritedly on a twisting mountain road. The system started and stopped faster which made the music sound more lively and energetic.

The impression that the Dmitri made the system sound “lighter” extended to a significant increase in soundstage transparency, dimensionality, and clarity. I was reminded of Jonathan Valin’s evocative description of the soundstage being “illuminated from within” in reference to Audio Research electronics. This was the effect the Dimiti had—a bigger and more open quality that did indeed remind me of that special quality of Audio Research electronics. Instrumental textures were more vivid and detailed, sounding simultaneously more palpable yet slightly farther back in the soundstage. The sound was cleaner, more transparent, and paradoxically, more vivid and relaxed. These impressions were consistent with two completely different front ends: the Spectral DMC-30SS preamp/SDR-4000 Pro CD player combination, and the Pass Labs XP20 preamp/Berkeley Alpha DAC pair.

Another salient characteristic was a smoother and more gentle treble; the Dmitri took off some edge in the top end, making the presentation more refined. The reduction in glare and concomitant softening of top-octave timbres made the presentation more realistic. The tambourine in Rimsky-Korsakov’s “Dance of the Tumblers” from Exotic Dances on Reference Recordings HRx, for example, sounded a bit like chunks of metal clanging together without the Dmitri. With the Dmitri in the system, I could hear the tambourine’s individual zils vibrating with a delicacy that was astounding. By reducing treble glare and hardness, the Dmitri allowed more of the instrument’s fine inner detail to emerge. Similarly, the Dmitri made strings more silken in texture, but not overly so. This improvement in the treble would alone be worth the price of admission.

Moving the Dmitri to the power amplifiers produced an even greater increase in dynamic contrasts, particularly transient bass impacts. In fact, I’d have to say that the difference was startling. Again, this was true with two very different amplifier designs, the Spectral DMA-360 and the Pass Labs XA100.5. The midbass was tighter and better defined, and the extreme bottom-end had much greater depth and authority. Adding the Dmitri was like removing a ceiling that had previously set a limit on the system’s dynamic contrasts. With the Dmitri powering the amplifiers, I also heard the same improvements in dimensionality, transparency, and timbre I heard when the unit was feeding the front-end components, particularly the increased treble smoothness. I was left to imagine what the entire system powered from the Dmitri would sound like, but I suspect that the unit’s positive effects would be cumulative.

Conclusion

The Running Springs Audio Dmitri delivers world-class sonic improvements in the areas in which AC power conditioners have traditionally excelled—smoother textures, greater dimensionality, and increased transparency. But the Dmitri takes this performance to another level with a wholesale increase in dynamics, bottom-end weight and impact, and overall transient quickness. Adding the Dmitri to my system took what was a great sound and made it even better in every respect.

At $5999 with the optional but worthwhile HZ AC cord, the Dmitri is priced at the upper end of the power-conditioning spectrum. But considering the significant sonic improvements it rendered, I would consider it money well spent. This is one AC conditioner that doesn’t ask you to make any sonic tradeoffs. After living with the Dmitri in my system and then taking it out, it was immediately apparent that the Dmitri was an essential component—and my new reference in AC conditioners.

SPECS & PRICING

Running Springs Audio Dmitri AC Conditioner

Power rating: 2400W
Number of outlets: 10
Dimensions: 14.75" x 6" x 10.75"
Weight: 67 lbs.
Price: $4499 (with standard AC cord); $4999 (with RSA Mongoose AC cord); $5999 (with RSA HZ AC cord)