High expectations for a low-power audiophile amplifier – CNET


First Watt SIT 3 power amplifier.

Steve Guttenberg/CNET

The First Watt SIT 3 stereo power amplifier brings out the hedonist in me; it somehow makes every recording sound more alive, more complete, more like the way music moves me in real life. Ah yes, that’s what high-end audio is all about, and here with the SIT 3 it’s hard to stop listening to music, it’s that good.

The design is unique, first because the SIT 3’s power transistors aren’t like any used by other current brands’ amplifiers. The SIT 3’s transistor is a static induction transistor, exclusively made to First Watt’s specifications.

The rest of the SIT 3’s circuity is also far from standard; the gain is just 11.5 dB, while most amps are 20+ dB, which in practice just means that for a given playback volume you’ll have to have your volume control set a little higher than other amps to achieve the same loudness with the SIT 3. That’s not a problem, just turn the volume up a little more.

Like all First Watt designs, the SIT 3 is a low-power fully Class A design, this one uses no feedback and it puts out just 18 watts per channel into 8 ohms, and 30 watt per channel into 4 ohms. Even so, I quickly learned the SIT 3 sounded terrific with my insensitive, hard-to-drive speakers, more on that later in this review.

Connectivity is basic, just stereo RCA input jacks and stereo binding posts for speaker cables. The all-metal chassis is nicely done, but it’s a no-frills affair. The SIT 3 is handcrafted in California, the price is $4,000 and production is limited to just 250 amplifiers. One other thing that makes the SIT 3 special is that Nelson Pass, the designer of the amp and owner of the company has his email address listed in the owner’s manual; he’s available to answer his customer’s questions.  

The SIT 3 measures 17 by 16 by 6.75 inches, weighs 32 pounds, and it runs warm to the touch. The parts-and-labor warranty is three years.

The review system consisted of TAD ME-1, Zu Soul Supreme and Magnepan .7 speakers, Pass Labs XP-30 preamplifier, Schiit Yggdrasil digital converter, PS Audio DirectStream CD/SACD transport, Parasound JC 3+ phono preamplifier, SME Model 15 turntable and an Ortofon Cadenza Blue phono cartridge. 


What does the SIT 3 sound like? Let’s start with luscious, organic and all there. When comparing the SIT 3 with another Nelson Pass design, the Pass Labs XA25, the latter is more concise and transparent-sounding. Both are solid-state designs, but the XA25 sounds more like what you’d think of as solid-state at its best. When switching between the two amps, both bass oomph and control show obvious improvement with the XA25, yet I miss the SIT 3’s more fleshed out, more organic tone. The XA25 is rated at just 25 watts per channel, but it played louder with greater ease than the SIT 3. 



First Watt designer Nelson Pass at his work bench.

Pass Labs

While my TAD ME-1s aren’t easy-to-drive speakers, the SIT 3 comfortably brought them to fairly loud volume (low 90 dBs) levels with ease, but if you really want to party, you would need to get a bigger, more powerful amp. High-power amps are cheap enough these days, but what the SIT 3 offers is something else again. It’s a sound you can lose yourself in. You really hear what makes the SIT 3 special first with vocals — they sound more human, natural and realistic. Same for acoustic guitars, horns, pianos, etc.

And not just with acoustic music; Brian Eno’s ambient albums, like Music On Land and Apollo, and Bill Laswell’s brilliant Panthalassa ambient remixes of Miles Davis’ electric tunes floated free of the speakers. The music is so much more ambient over the SIT 3; the music expands to fill my entire listening room.

With bluesman Roosevelt Sykes’ Feel Like Blowing My Horn, I hear more of the band’s interplay; the SIT 3 creates a clear portal back to the 1973 session. That’s it; the best amplifiers somehow allow the music’s essence to cut loose.

Then I hooked up a much more powerful amp, the Bel Canto REF500S, which pumps out 400 watts a channel into 4-ohm speakers! Switching between the REF500S and the SIT 3 while listening at moderate loud volume (80 dB peaks) to the Dave Brubeck Trio & Gerry Mulligan album, the SIT 3’s sound was so much more dynamically alive. Brubeck’s piano and Alan Dawson’s drum kit were more fully present, and the stereo imaging’s dimensionality trounced the REF500S. So it’s interesting that the 30-watt-per-channel amp sounded more alive than the 400-watt-per-channel amp, when played at moderately loud volume. Of course when I played the music a lot louder, the REF500S’s sound pulled way ahead of the SIT 3’s. To be fair, the REF500S amp sample is 8 years old and may not represent what the current version of the REF500S sounds like.

I was concerned that I wasn’t being fair listening to the SIT 3 with just the ME-1s, which are low-sensitivity speakers, so I also spent some quality time listening with a pair of high-sensitivity speakers, the Zu Soul Supremes. Because of their much higher sensitivity I was expecting that the SIT 3 would sound more powerful, with more dynamic oomph with the Soul Supremes, but they didn’t.

So I exchanged emails with Nelson Pass, and he explained the SIT 3 sounds best with 4- to 8-ohm speakers, and the Soul Supreme is one of the rare high-impedance 16-ohm speakers. He suggested hooking up a 16-ohm resistor in parallel with the speakers, and that little tweak transformed the sound!

While listening to the SIT 3 and the Supremes to Ernst Reijseger’s Cave of Forgotten Dreams soundtrack for the Werner Herzog film, the sound of the chamber orchestra was positively lucid. The low-in-level, quiet details of the sound added much to the realism of the music. Meanwhile, 1960s-era Frank Sinatra albums are some of his best-sounding, and I had goosebumps hearing Sinatra with the Nelson Riddle Orchestra swinging like a big jazz band. The SIT 3 really does communicate rhythm with gusto!

Lastly, I hooked up my Magnepan .7, yet another low-sensitivity speaker, and the SIT 3 was a great match. Bass was bigger and bolder than usual from these speakers, and there was more soundstage depth; the “spaces” between the instruments and vocals on audiophile recordings like Doug MacLeod’s Break the Chain CD were illuminated by the SIT 3. There’s real magic going on between the SIT 3 and the .7 speakers. 

Summing up, the First Watt SIT 3 is just the amp for audiophile connoisseurs seeking a more relaxed and sweeter sound. For you music lovers who don’t listen at high volume, the SIT 3 will be a feast for your ears. I’ve never heard anything like it.