Stromtank S-1000 Review – Ed Gatto

I had a whole-house generator installed a couple of years ago and immediately felt my soundstage in my listening room had shrunk and the musical engagement diminished.  Then, I happened upon Michael Fremer’s article about his problems with his installed whole house generator.  He got expert help from Audio-Ultra to significantly upgrade his electrical service to his house and listening room. It was a very expensive, but effective, solution.

I first learned about the Stromtank Regenerators at the Capital Audio Fest.  Audio-Ultra had one on display and educated me on its purpose and its capabilities.  I wondered if the Stromtank S-1000 could solve most, if not all, of my electrical supply noise problems.  Time passed…

We upgraded our listening experience buying a C.A.T. SL-1 Renaissance BPA preamp and shortly after auditioning the C.A.T. JL7SE monoblocks at the same Capitol Audio Fest, bought them too.  Both purchases improved our listening experience, the C.A.T. power improved our systems performance filtering most of the electrical noise, but we wondered what we might still be missing.

A year later a great opportunity dropped into our laps.  We had been auditioning new loudspeakers (the weak link in our system by that time).  Our friend and local audio dealer, Audible Images in Melbourne, FL, made us on offer on his dealer demo Wilson Audio Specialties Alexx loudspeakers.  Another huge increase in listening experience.  The combination of C.A.T. Triode power and the Wilson Alexx provided a grand scale of musical reproduction… detail, soundstage, resolution.  Amazing!  We felt blessed, but what might still be missing?

Enter our friend at Audible Images.  He had received a Stromtank S-1000 and had it on display.  He hadn’t had time to sit down and really evaluate its performance.  In fact, it was in his smallest room and set up.  After a few weeks, he asked me if I wanted to demo it at home and let him know what I think.  He routinely sends equipment home to get my listening viewpoint.  I said, “SURE!”

I brought it home, put it in position, and powered it up to charge the big battery.  First, we listened to our system without it installed to get a sense of the baseline.  Then plugged the front-end of our system into it – C.A.T. SL-1 preamp, CD Transport, DAC, and Turntable power supply.  And we played music with the Stromtank in the ‘blue’ hybrid mode – charging and powering through the battery and inverter.  Huh… is there something different?  We’ll see (or hear?).  After 20 minutes, I got up and pushed the button to the ‘green’ off the grid mode on battery/inverter only.  WOW!  There was a clearly audible difference, and I was standing at the side of the room.  Was it better or different?  I felt like the bass went deeper, the voices and instruments had more definition. My wife hit the nail on the head, she felt the music was more real.  She felt the music was LIVE.  Yes, it was better.

It was hard to argue.  The soundstage was deeper, wider, taller.  More noticeable spacing between voices and instruments.  The edges of the between voices and instruments seemed rounder yet more detailed in presentation.  The decays were longer and more defined.  Beautiful, engaging. 

I shared our experience with Audible Images.  He agreed that’s what he thought but his time with the Stromtank was limited.  I reluctantly returned it to him.  We weren’t ready to put out the retail price for it at this time.

Then we got the call.  Do you want to buy it as a dealer demo?  We said, “Yes”.  A week or so later, I drove up to get it.  Our dealer had finally put it into his reference room.  I spent many, many hours in this room so I’m quite familiar with its sound. We’re talking DCS, D’Agostino, and the new Wilson Sasha V.  My friend was busy with customers in another room, so I dropped into the sweet spot and put on some tracks I use to evaluate systems.  The Stromtank was in ‘blue’ hybrid mode.  I listened to the 3 tracks, and they sounded superb.  Then, I put the Stromtank into ‘green’ off grid mode.  WOW!  Again, I immediately heard the same differences I heard in my listening room.  Two times now I’ve cleared heard the differences.  They may be subtle, but they also seem significant.

When my dealer finally had time, we sat together.  He shared that he should have put the Stromtank into his reference room sooner.  He heard the same improvements that I had.  We agreed they were significant.  I was happy to pack it up and take it home.

At home again, I went through the same process.  Played our system without the Stromtank while charging it.  Then connected my system to it.  The same perceptions hit me when playing from it.  Although, this time I felt the sound stage floor was lower… amazing.  Three times I’ve heard these improvements.

Without any direct measurement the answer must be the much lower noise floor allowing more low-level detail to be reproduced and the more coherent AC sine wave being supplied to the equipment.

I’m a believer!

I’m also an audiophile and wonder what would happen if I cleaned up the AC supplied to the C.A.T. JL7SE monobloc power amps.  Hmmm.