Solid State Preamp Reviews

Larry Greenhill reviewed the BP-17³'s phono & DAC modules in June 2019 (Vol.42 No.6):

After reviewing Bryston's BP-17³ line preamplifier ($3995) in June 2018, I returned the review sample to Bryston to have its optional DAC and moving-magnet phono modules installed ($750 each). I was curious to hear if these options would maintain the high standard set by this component, which is included in Stereophile's "Recommended Components."

When the BP-17³ returned, it looked unchanged. But when I removed its top plate, I saw that two new daughterboards had been installed above the motherboard: the DAC module on the right, the phono module on the left. The new high-resolution DAC module has two TosLink inputs and two transformer-isolated coaxial S/PDIF inputs, selectable from the front panel. The data are directly passed on to a single AKM 4490 DAC, which has a single-ended output. Unlike Bryston's flagship standalone D/A processor, the BDA-3 ($3495), this new card doesn't decode DSD data. The new card's specified total harmonic distortion plus noise in the audioband is 0.002%, an improvement over Bryston's previous add-on DAC modules, made for their BP-26 preamplifier.

The BP-17³'s moving-magnet phono module employs two-stage RIAA equalization; James Tanner, Bryston's vice-president of marketing, sent me a graph that shows the EQ section's extreme accuracy. An optional rumble filter is available with a factory order, or in the field with a change of capacitors.

Adding these modules to the BP-17³ changes its input architecture. The base model has seven line-level analog inputs—two balanced (XLR) and five unbalanced (RCA), with one of the latter designated Record. Adding the MM phono module drops this to six line-level inputs and assigns the MM phono input to the pair of RCA jacks labeled Input 2. (Once the phono module is installed, Input 2 can only be used with a turntable.) Installing the DAC module also changes the input count: It activates the preamp's two TosLink digital inputs—D1 and D2—and allows the pair of RCA jacks labeled Input 1 to be used as two distinct S/PDIF digital inputs: D3 and D4. But even with the DAC module installed, as long as no S/PDIF digital sources are connected, Input 1 can still be used as a line-level analog input.

Setting up the upgraded BP-17³ was straightforward, with no glitches encountered. I ran an unbalanced S/PDIF interconnect (RCA) from my Bryston BCD-1 CD player to the left-channel jack of the Bryston's input 1 (D3), and a single BNC-to-RCA interconnect (footnote 1) from my Bryston BDP-3 media player to the right-channel jack of the BP-17³'s input 1 (D4). And because I needed to use Bryston's TF2-30 moving-coil step-up transformer ($1500) to boost the 0.2mV output of my Spectral Reference MC cartridge for the MM phono module's input, I ran unbalanced interconnects (RCA) from the TF2-30 to the right and left jacks of the BP-17³'s input 2 (phono).

Listening
The BP-17³'s DAC upgrade grabbed my attention from the get-go. I was surprised by its slam, snappy transient response, and transparency. Driving the Mark Levinson No.534 power amplifier, the expanded BP-17³ produced engaging, detailed, tonally captivating, utterly natural sound. The sound of the vibraphone that accompanies the male vocal ensemble Cantus in John Atkinson's recording of "Introit: Benedicta sit Sancta Trinitas," from Cantus (CD, Cantus CTS-1207), was translucent, liquid, and glowing. At the end of the Piè Jesu of John Rutter's Requiem, in the recording by the Turtle Creek Chorale led by Timothy Seelig, the DAC clearly depicted the sopranos' lilting voices over the pipe organ's massive pedal chord (CD, Reference RR-75CD). The ominous bass synth in "Silk Road," from I Ching's Of the Marsh and the Moon (CD, Chesky WO144), pressurized my room. With "Gabriel's Oboe," from Ennio Morricone's film score for The Mission, as arranged by Ralph Ferris for the chamber ensemble Ethel (MP3 file recorded from SiriusXM Radio's weekly show Living American), the BP-17³ drew me in as has no other audio component. The augmented BP-17³ reproduced the full power of the violins' fierce, fast pattern, coupled with pounding drums and brass, in Bruckner's Symphony 9, with Claudio Abbado conducting the Lucerne Festival Orchestra (24/48 download and CD, Deutsche Grammophon 479 3441/HDtracks).

At first the BP-17³'s phono module sounded more neutral than I liked, but I soon realized that it was allowing me to focus on the music longer than usual, with less fatigue. This was particularly true with the score for Glory (LP, Virgin America 91329-1), composed and conducted by James Horner and produced and mixed by Shawn Murphy. I relaxed, drawn into the orchestral dynamics and the lilting voices of the Boys Choir of Harlem in "Call to Arms," one of the most melodic of Horner's compositions for film. The soundstage was wide and deep, with the fife and snare drum set in a distinctly different layer from the singers.

Bryston's new phono module also did well by Russian ballet music, including Dance of the Knights from Prokofiev's Romeo and Juliet, with Erich Leinsdorf conducting the Los Angeles Philharmonic (direct-to-disc LP, Sheffield Lab 8), and the suite from Shostakovich's The Age of Gold, with Leopold Stokowski conducting the Chicago Symphony (LP, RCA Living Stereo LSC-3133). The phono module reproduced the rich orchestral timbres, silky strings, intense and driving rhythms, and wide, deep soundstages captured on both of these recordings.

The Bryston preamp's new phono section inspired me to revisit some of my favorite jazz LPs, including Michel Legrand's Legrand Jazz (LP, Columbia CL-1250), particularly his arrangement of Thelonious Monk, Cootie Williams, and Bernie Hanighen's "'Round Midnight," with Herbie Mann (flute), John Coltrane (tenor sax), Miles Davis (trumpet), Eddie Costa (vibes), Paul Chambers (double bass), and Kenny Dennis (drums). I'd never heard Davis's solo trumpet come through so distinctly, so clearly, and so beautifully.

Summary
How did the upgraded BP-17³ sound in comparison with other preamplifiers I had on hand? As noted in my review of the BP-17³ in June 2018, matching it to the right amplifier—in my case, a Mark Levinson No.534—was critical. That done, the upgraded BP-17³'s dynamics, punchy bass, slam, and soundstage depth matched those of my Mark Levinson ML-7 preamplifier and easily bettered those of Bryston's BP-26. However, neither the upgraded BP-17³ nor the ML-7 attained the transparency, transient response, and freedom from midrange grain of the Mark Levinson No.526 preamp, which costs considerably more ($20,000).

That said, the BP-17³'s optional modules exude top build quality and engineering excellence. They use high-quality PCBs with no point-to-point wiring. They should last for years and be easy to service. Adding these modules requires no changes to the front or rear panel, and no new connectors or switches. Low-level phono-cartridge signals or digital datastreams can be managed with the existing front-panel controls and/or Bryston's optional BR-2 remote control ($375). However, audiophiles who stream their libraries of digital music will bemoan the DAC's lack of a USB or HDMI input and user-selectable PCM filters. More important, the DAC module can't decode DSD files.

Bryston's à la carte upgrade plan may at first produce sticker shock, as a fully maxed-out BP-17³ costs a total of $7370: $3995 for the base preamplifier, $375 for the BR-2 remote, $1500 for the DAC and phono modules, and $1500 for the TFA-30 step-up transformer (if you use an MC cartridge). But that's still less than the cost of 17 of the 22 other solid-state preamps listed in Class A of "Recommended Components"—and at $750, the integrated DAC module costs only 22% of the price of the BDA-3, but sounds as good, I felt, with PCM files.

Bryston's optional phono and DAC modules and BR-2 remote control greatly increase the BP-17³'s strengths while maintaining the high standard set by the base model. They integrate high-quality phono and DAC functions without the need for separate components and their interconnects, and they sure save shelf space. For most BP-17³ owners, these upgrades should be no-brainers.—Larry Greenhill

---

Footnote 1: Because the Bryston BDP-3's S/PDIF output has a BNC jack, I used a Bryston LV61S BNC-to-RCA 75 ohm coaxial cable ($120).