Review: Running Springs Audio Dmitri AC filter


Category: Accessories

Just about three and a half years ago, I went through a comprehensive home auditioning process of AC power conditioners. After reading reviews and talking to different audiophile friends I selected four very highly regarded pieces and the clear "winner" was the Running Springs Audio Jaco AC power conditioner. The Jaco in my system did everything better(transparency/micro-details/liquidity/soundstage layering/timbres) then the other AC conditioners and very importantly did not damage the macro-dynamics/prat/slam as the other conditioners had when I had them in my system. If your interested in more details take a look at my review of the Jaco here on the GON.

I believe that Running Springs Audio is a company with integrity that would not come out with a new reference just to get a new piece to the market, unless they believed that they had come up with a better "sonic mouse trap", in my opinion, with their new Dmitri AC power conditioner and HZ power cord they have come up with a "sonic mouse trap" that could easily capture a Blue whale.

As in all my reviews if your interested in technical details I advise you to go to the RSA website. The weight of the Dmitri is 67 lbs. and is a rather handsame piece with a carbon fiber face plate, along with carbon fiber being used internally for acoustic damping and carbon fiber feet. It has ten outlets with a power rating of 2400W. The Dmitri comes with a stock power cord or can be ordered either with an upgraded cord the Mongoose or the top of the line HZ reference cord.

On to the most important part of any review, the sonic performance of the piece:

1) A very significant increase in clarity/transparency/liquidity through out my total system.

2) With this increase of transparency and the lowering of the overall noise floor micro-details, decay trails, and the acoustic space of recordings became much sharper and easier to hear.

3) A precision in the location of individual players and more air around them with more natural layering in the soundstage. The music just makes more sense.

4) Timbres sound more real/natural across the entire sound spectrum.

5) Finally, what I still find to be somewhat of a paradox, the overall macro-dynamics, prat, and speed of my system jumped to a much higher level, yet what I subjectively call the "liquidity/easyness/relaxation" level increased at the same time. My system was already pretty damn good at letting the listener just relax into the music, with the Dmitri it's even better!

I also ran the experiement regarding the upgraded power cords effect on the overall performance of the Dmitri, to cut through the chase, the reference HZ power cord allows the Dmitri to perform to its ultimate level across the entire sonic range with even a more fleshed out midrange and deeper bass and speed and is with out a doubt worth the extra expense.

Is the Dmitri the "BEST" AC power conditioner in the world, I don't know because I did not audition all the highly regarded AC power conditioners that have gotten great feedback and buzz among audiophiles. I don't believe a "BEST" anyways, there's a lot of great pieces of gear, along with personal taste and system synergy to take into account. However, if your looking for one of the best out there, I would recommend you put the Dmitri on your audition list. It surely is not inexpensive, it retails with the HZ power cord for $6000.00, but I know individuals who have spent more on linestages and amps who got less bang for there buck, then I got out of upgrading to this AC power conditioner in my system.

Associated gear
Click to view my Virtual System
teajay

Good one acresverde :-)

Forgot to mention, I was using a CH Acoustic X-20 power cable. It's the successor to the Crown Jewel power cable and is vastly superior to anything I've heard except for the CH Acoustic X-30 power cable (which is the next step up and the top model power cable).

Regarding the lean sound - I believe the Dimitri allows the system to perform to it's potential. My system never sounded lean - it was ultra transparent with whatever it's fed.

Finally - one should realize, passive power conditioners can experience a wide variety of variations and contaminations of incoming power - so individuals may experience different results. Best way to determine what works best in your system is simply to try it.

Hope this helps.

I’ve been using a Dmitri for 4-5 years on a music system.  This replaced a Haley which I had been using since 2007ish until an outlet failed.  I finally replaced that as reported in another A’gon thread; the Haley is alive and kicking again.  But, I recently got a great deal on a second Dmitri, this time for surround system upstairs.

Power cords in the music system have been exclusively Dream State (DS) since 2006-2007.  I had read about the Craig Hampel HZ Crown Jewel (CJ) cord but this was next to impossible to find.  On another thread here, Craig writes that there are 30 or so CJ cords out there.  The other RSA cord option years ago, the Cardas “Mongoose”, did not appeal to me after much experience with other Cardas cables. I ran with the DS cables and tried various Silent Source (SS) and Stealth variants in these years.  Nothing displaced the DS.  The SS cables are nicely refined but just too mellow for me at this point.

Two years ago, a CJ became available.  I was slowly updating the system with Craig’s X20 IC’s & Spkr cables….and I had one X20 power cord for the preamp.   First thing was to replace the DS into the Dmitri with the CJ.  Tonal coherency was unchanged except for a slightly more extended lower bass.  But wow, the boost in dynamic contrasts.  This is a signature result every time I drop in one of Craig’s cables.  And then the clarity.  The DS had been my reference cord in this regard into the Dmitri, but the CJ brought on another level of clarity.  There was no change in tonality, “warmth”, prat (whatever that is), blah blah blah.

For the next several days and weeks, I tried many combinations.  I put the DS into the preamp so that I could free up the X20 cord.  The DS is a great cable, but taking out the X20 made me aware of its magical properties here, the bass, clarity and dynamics (BCD).  This triplet of refinement repeats itself with every new CJ or X20 insertion into the system …… except one place!

I danced the X20 cord around the front-end components.  Each time the X20’s refinements over the DS were observed.  I then replaced the CJ with the X20 into the Dmitri.  This did not go well.  I tried a few tracks but the X20 was just not a good fit here.  A return to the CJ into the Dmitri and all was smooth and natural again. I put the X20 back into the preamp.  Out of curiosity, I plugged that X20 directly to the wall.  The result was a major collapse of the dimensionality vs. driving the preamp from the Dmitri.

A couple of takeaways here:

1) Some people here have written that Craig has told them to plug his cables directly into the wall and not into a power device.  I’ve had many communications with Craig, and he never told me to do or not do one thing or the other.  My experiences here made it very clear the significant benefit of having the preamp (with the X20) plugged into the Dmitri.

2) There is discussion that the Dmitri results in a lean outcome.  With the fully tubed system, preamp, DAC, phono and Rogue Audio Apollo or the Symphonic Line (SL) Kraft amp, this system has harmonic structure, decays and dimensionality in spades.

A couple months after this, I got an RSA Duke and another CJ cord.  I changed the SL amp from directly into the wall to the Duke.  With the CJ into the Duke, and wow wow, there’s that BCD again.  The greater dynamic contrasts are immediate  And this is after the constant commentary in these forums that claim power devices reduce dynamics when used with amplifiers.  Well, not here.

A few more X20 cords have arrived since, each time adding the same refinements that I have not experienced before from one cord change after another after another.  The comments about the X20 by @tjassoc match with mine.  Moving from the DS to the X20 is an easy change as both have an incredible neutral tonal coherency.  There is no need to have one product with one set of tonal issues to “match” with another product with complimentary tonal issues to achieve “synergy”.  This easily allows for evaluating the RSA products which also do not alter the tonality of the system, I.e., no added “warmth” or artificial treble detail.  I would love to dance one or two X30 cords around my system to hear the effects, but they are way way way outside of my affordability.

I have been using the RSA Haley into the surround system for the last few years: Classe 800 processor, Symphonic Line amp, Oppo 203 player, rebuilt Duntech Sovereigns, X20 ICs and spkr cables, DS cords to processor, amp and player. I started with the DS, then the CJ and then the X20 cords into the Haley.  I struggled to hear a difference between the 3 cords.  I then switched out the Haley to the second Dmitri.  I re-ran the 3 cords through this.  The CJ over the DS was a mighty nice refinement.  Not so much the dynamics, but the extended bass and clarity were evident.  The Dmitri showed up this difference that the Haley could not.  I then changed from the CJ to the X20 into the Dmitri, expecting a not so good result as I had with the X20 / Dmitri in the music system.  But this time, the X20 quite handily outperformed the CJ.  There was much more detail and energy in the trebles.  I went back to the CJ; too much detail and clarity was lost with this change. The X20 into the Dmitri was the clear winner in this link in the surround system.

Having many X20s and the DS’s in the two systems greatly helps to hear such significant benefits of the RSA products.  Considering that the Dmitri is in the $1000-1400 range these days, it is an absolute steal.  With the performance that these devices provide, I just don’t have the itch to try out newer products, especially if I have to pay $5-10k to get any significant improvement.  I had the $5500 retail Sound Application device before I tried the Haley, and the Haley tore up the SA and the Audio Magic Eclipse too,  So I have no interest to try another SA device.  Long live the Dmitri!

John

jafox

Thank You for the detailed and thorough review of RSA conditioners. I have been thinking about adding one to my system. Good to learn that these products are still relevant on 2025.  I enjoyed the Cable discussion as well. I am not familiar with 

Craig Hampel. Impressive that his Crown Jewel (CJ) beats out Silent Source, Stealth and Cardas.  Is Craig still making cables/cords?

 

Happy Listening! 

jafant

A few years after I got the Haley, I did some reading to find out what other RSA owners were using for power cords.  That was when I learned about the CJ power cord. I suspect the review below caught my attention years ago.  Looks like the reviewer posted it twice and each thread went on its own path with different responses.  Notice Craig's many responses here with much detail.  The other guys are not too kind on Craig's minimal website.  And his current website is even more minimal!  Funny.

CHA X15 Review 1

CHA X15 Review 2

After I got the first Dmitri many years later, I returned to the thought of power cords that were sold with the RSA devices years before. I must have gone back to find this review again.  And that was when I went on a serious quest to find a CJ cord.  But these are hard to find on the used market as Craig points out in the above review.  After I had much time invested playing with Purist Dominus, Kubala-Sosna Emotion, Stealth M5000 and Dream, Silent Source Music Ref and brief times with a few other power cords,  I had become content with the Dream State cords all these years.  But I wanted to try a CJ.  And by then, I had learned much about the X20 cables.  My communication with Craig began.  He has been incredibly responsive to all my questions about his products, past, present and upcoming.  And he throws all sorts of tidbits of advice at me as well.  You gotta love this kind of customer service.

So please hunt down threads on CH Acoustic X10, X20 and X30 cables.  Here is one example:

CHA X20 Thread