AXPONA 2013 - Part 2

Show report
Solid-state power amplifiers,
Tubed power amplifiers,
Solid-state preamplifiers,
Tubed preamplifiers,
Digital-to-analog converters,
AXPONA 2013 - Part 2

Audio Note brought a set of room-friendly stand-mounts, the K/SPe ($3,700/pair – stands are an extra $650). 90dB/wm 2-ways with an 8” woofer and a silk dome tweeter, and the sound was surprisingly full-bodied. Okay, not really a surprise, as this is exactly what Audio Note is known for, but whatever. The OTO SE amplifier ($5,500 as a linestage, $6,300 with the phono), an EL84-based integrated was fed by a Stellavox SP 7 analog tape deck, plopped on a convenient chair. Pretty cool – more tape!

Benchmark Media was showing their new HGC all-in-one, a DSD-capable DAC, a preamp, and headamp, supporting asynchronous USB that they released last November. The HGC is a hybrid design – with digital inputs, all signals are attenuated by a full 32-bit DSP. The analog inputs, and there are two, are not converted, but instead are attenuated by their very own analog volume system. Color me shocked – and pleasantly so. This is a compact package, folks, and some cutting edge tech that I hope to hear more of in the future. Here, it was paired with speakers and electronics from Studio Electric. The new T5 floorstanding loudspeaker features a horn-loaded compression-driver tweeter mated to an 8” paper-cone pro-audio driver with a 2.5” voice coil. Nominal impedance is 7 ohms, with a 90db/wm sensitivity and a frequency response of 38Hz-19.5kHz. The bass-reflex cabinet is 1” thick. Prices start at $5,100 for black; an upgraded wood horn adds $400. A variety of exotic woods (for the horns) will be available; it was shown here in a reddish Puduk, not exactly my favorite combo. I think Info should hit their site in about three weeks.

Herron Audio had a room full of … Herron Audio. Some prototype loudspeakers stood tall in the room’s front wall corners and were paired with some familiar and some not-so-familiar Herron gear. Starting with the amps: M1A monoblocks ($6,850/pair), good for 150wpc in 8 ohms and 275 into 4, these were paired with a VTSP-3A (r02) vacuum tube preamp ($6,550), a single-ended only design with a mono switch, HT bypass, mute, dual outputs, a tape loop, 100K ohm input impedance and 100 ohm output impedance. Dude. Wow. A prototype DAC that does PCM to DSD up-conversion helped out with the input, and a big VPI Classic 3 in luscious rosewood ($6,000), sat atop the rack, was wired up to a VTPH-2 vacuum tube phono stage ($3,650).

Wadia’s new Intuition ($7,500) is an integrated amplifier with onboard DAC that made a huge splash at CES. The aesthetic was designed by sister-company Sonus Faber, and the clean, flowing lines are certainly a departure – a welcome one, as this is a pretty neat looking piece of kit. The unit is entirely digital – a 32bit AD/DA engine sits at the heart, which means that both analog inputs are converted before being passed over to the FPGA system for attenuation, and off to the ESS 9018 Sabre DAC chip for decoding back into an analog signal. DSD is supported over the 32bit/384 kHz USB input. The unit is not a typical Class D – Wadia calls it “Class D+” – and these bits are not sourced from B&O or Hypex, but comes from an “Italian innovator” – the output stage is solid for 350 wpc of output. Available in silver or black, shipping begins in April.

Big transmission-line loudspeakers and triodes may not be the first pairing that comes to mind, and that’s a shame. Because they do make a damn fine pairing, a fact that Robert Lee of Acoustic Zen and Santy Oropel of Twin Audio Video, the importer for Triode Corporation of Japan, have proven repeatedly on the audio show tour circuit. The imposing (60lbs each) TRX-M845SE SET monoblocks from Triode feature a 845 output tube and provide a very robust 50wpc into the Acoustic Zen Crescendo loudspeakers ($16,000/pair). The sound in here was totally non-fatiguing, with deep bass, a darkly luscious mid range and a sweet treble that had me thinking terrible thoughts about my bank account. Beautiful gear making beautiful music? I love it when that happens.

Perhaps it was inevitable that audiophile-level computer audio would become a dark warren of thorns, snarling teeth and black magic, but if you’re lost, Rob Robinson is one of the precious few in audio’s high-end who actually knows what the heck he’s talking about. Rob created a couple of nifty little programs for his company Channel D and has had some success converting the unenlightened to the multitudinous joy that is digital. I’ve been using Pure Music ($129), now in version 1.89, for several years now, and I’ve been nothing but a satisfied customer that entire time. One program I haven’t tried out is what Rob’s been using for converting vinyl, called appropriately enough, Pure Vinyl ($279). Suitable for archival as well as vinyl playback (!), Pure Vinyl also lets you fix your old records, “non-destructively” smoothing out those surface defects you can’t clean away, the ones that make those pops and ticks, while preserving the “warmth, clarity and dynamics of vinyl reproduction”. Just add an AD/DA converter, and you’re off. Speaking of which, Rob was showing with a Lynx Hilo “Mastering Quality” USB ADC/DAC ($2,499), with native DSD support, which he used for all the conversions to and from the computer. Playback assistance came from a Hegel Audio H20 200wpc stereo amplifier ($5,750) and a pair of Joseph Audio Pulsar loudspeakers ($7,000). The sound from this setup was just shockingly good.

Analog playback came from an Artemis Labs SA-1 turntable ($7,800) mounted with a Kuzma 4Point tonearm ($6,500) and Zu Audio Grade 2 Prime DL103 phono cart ($650). The way it works: a Channel D Seta Model L+ phono preamplifier ($5,799) diverts the “flat” analog signal directly to Pure Vinyl for the application of the RIAA curve, correction, archival, and/or playback through the USB ADC/DAC. Another clever device, the Seta DAC Buffer “Transimpedance Amplifier”, takes the analog signal come out of a DAC and applies extremely high-quality analog attenuation so that a DAC can stay within it’s sweet spot of plus/minus 12dB – any more play than that, and many DACs audibly lose resolution. Even if you choose to go with zero attenuation, the Buffer still brings a killer-app to the party, and it’s something that most DACs lack – wicked-good impedance matching. The Seta Buffer has a two mega-ohm input impedance and an absurdly low 20 ohm output – your DAC has never driven your amplifier directly anywhere near this well. Now with single-ended outputs, the Buffer is still balanced-only on the input (for common-mode noise rejection). I’m getting one of these bad boys for myself.