Well, it's been a while, and I'm finally able to post my impressions of the RWA Sig 15. The unit's been broken in for some time, but life intervened. Now that I've cleared the decks, I can gather my thoughts and discuss how the Sig 15 sounds.
My setup is unusual. I have a dedicated listening area, but I realized that I never really use it. Instead I spend time in the living area, working on the computer and keeping an eye on my son. So I took the plunge and reoriented my system into a new arrangement, centered around three pieces of gear which are all, oddly enough, 6Moons Blue Moon Award winners:
DAC - Schiit Bifrost
Amp - Red Wine Audio Signature 15
Speakers - JohnBlue Audio Art JB3
Interconnects are Straight Wire Silver (computer to DAC) and Zu OxyFuel (DAC to Sig 15), and the speaker cable is Speltz Anti-Cable. I've ripped my CD collection to an external hard drive via JRiver Media Center. Everything's in FLAC format, and I'm using Media Center's WASAPI mode to eliminate Windows from the signal path. For other sources, an old Pioneer TX-710 tuner allows me to pull in a great local college radio station.
The JB3s are quite the little marvels. They feature a single 3" full-range driver, they're front-ported, and each is about the size of a toaster. A great deal of care and quality goes into their construction - check out the 6Moons review for the details - and they have a wonderfully sweet, open, and fast sound. They're set up in the classic equilateral triangle pattern, with about a meter between both the speakers and the listening position. I have them on Ultimate Audio monitor stands to get the drivers pointed at my ears.
For the first ten hours or so, I expected nothing more from the Sig 15 than for it to settle into the system. I did notice some immediate improvements over my previous amp, such as a wider and slightly taller soundstage. The noise floor was noticeably lower. A few tracks started to hint at what was to come. For example, the acoustic guitar work on "The Prince's Favorite Son" by Dog's Eye View came alive, conveying the sense of real musicians working in natural space.
Over the next forty hours, the Sig 15 gradually opened up. Early on, it would take as much as twenty minutes for the system to warm up and reach full voice, but once that burn-in period passed the amp sounded fine right after a cold start. I noticed that the Sig 15 gave a clear and relaxed presentation even to weak sources. Frequently I listen to online radio, usually on a sonically subpar 96kbps feed The Sig 15 made those sources much more palatable, and they held together better at higher volumes than with my old gear. During this period, the real strength of the Sig 15 began to shine through - presence. We're all aware of that elusive quality that distinguishes "music" from "sound coming out of a box." Let me tell you, the Sig 15 has that quality of presence in spades. When a band is really cooking, it becomes a complex and living creature. With bands like Steely Dan and the Dave Matthews Band, the Sig 15 truly catches the life of the performance.
Around fifty hours the sense of presence became dramatically stronger - perhaps due to the cathode fully forming on the tube. The Sig 15 displayed a natural sense of attack, and the sound became more stable and assured. The amp handled even complex and murky passages with aplomb. For example, self-proclaimed "nerd rockers" Kirby Krackle employ a distortion-heavy, garage-rock sound. My previous amp would render them smeared or murky, but the Sig 15 makes them sound crunchy and alive.
After fifty hours, improvements became less dramatic. Extension at both the top and bottom improved. The JB3s have tremendous treble response, which can become glarey, but the glare eventually smoothed out and subsided. The organic quality of the sound continued to impress. While listening to jazz on the college radio station, I could easily switch gears between hearing the individual performers and hearing the group as a whole.
To sum up, for me the defining quality of the Sig 15 is presence. Switching to pure battery mode makes that sense of presence a bit clearer, but it's always there. One unexpected benefit of the Sig 15 has been its portability. I'm rebuilding the speakers in my main rig, and it's great to be able to pick up the amp and carry it from room to room when it's needed. (In fact, I may be able to do away with a second amp altogether once the rebuild is complete.)
I'm tremendously pleased with my RWA Signature 15. I see that other audio manufacturers are jumping on the battery power bandwagon, which I take as a testimony to Vinnie's prowess. I wish him and Red Wine Audio all the best going forward.
