RePrint of
HOME THEATER Nr. 10/03
europe's largest home theater magazine

BRYSTON
SP 1.7 DECODER/PREAMP AND 9B SST POWER AMPLIFIER

Reference Class 1+

Congratulations!

The rapid developments in the home movie market bring forth abundant new audio formats. While some manufacturers regularly present completely new models, at Bryston they always remain conservative, and refine the time proven range of models. What the new version 1.7 of the legendary decoder/preamp SP1 has to offer, you'll read in the following pages One topic right up front: Owners of the superb THX Ultra licensed SP 1 don't have to worry, since complete hard and software updates to the SP 1.7 are realizable, without problems, at any time.

Decoder-Preamp SP 1.7

The first class workmanship and the straightforward operational philosophy of the SP 1.7 has not been altered. However the chain of the usable audio formats has become somewhat longer. The most important change is the increase to eight outputs, in order to accommodate 7.1 channels with Dolby Digital EX or DTS ES. For the most important six channels the back of the SP 1.7 additionally incorporates XLR sockets with balanced signals, while Surround Back (SBL, SBR) are only available via RCA (Cinch) sockets. The SP 1.7 communicates with the outside world by means of six analog stereo inputs, one six-channel input (DVD-Audio and SACD), as well as four coaxial digital sockets. Two optical inputs are optionally available if one relinquishes the balanced AES/EBU input.

In the interior of the SP 1.7 Bryston has retained the high quality input switching system via relays, as well as the completely analog signal path (including analog potentiometer) for unadulterated stereo operation. Basically the audio section corresponds to the audiophile BP-25 preamp. Completely new, however, is the processor circuit board, which thanks to the Motorola DSP 56367 IC offers more than enough computer power. The entire assembly of the SP 1.7 is "typically Bryston", i.e. extremely robust and a classic example of flawless engineering know-how. Two extensively regulated circuit sections (for the analog and digital sections), fiberglass reinforced epoxy circuit boards, short signal paths, and completely discrete output stages for the analog outputs are no witchcraft, but perfectly executed handiwork. Finally Bryston offers, without batting an eyelash, a full 20 year (!) warranty for all of its products.

9B SST Five Channel Power Amplifier

We also found the matching power amplifier for the SP 1.7 at Bryston. Behind the designation 9B SST hides a prodigious powerhouse: 5 x 230 Watts into 4 ohms with extremely minute distortion are technically a guarantee for powerful sound. Some readers might recognize the roughly 30 kilogram (65 pounds) "powerblock", because its predecessor was tested in Issue 4/2001. The improvements of the new 9B SST amplifier are found in the new output transistors, improved circuit board layout, and a new grounding protocol. Besides somewhat higher output (from 215 watts to 230 Watts), the damping factor, distortion factor, and signal-to-noise ratio have been improved from very good values to excellent values. The ingenious circuit technology in which both an npn and a pnp transistor work in parallel for each half-wave remained, and thereby completely eliminate the usual (slight) unbalance of conventional circuitry. In order to assure optimum sound the developers have dispensed with fuses and relays in the signal path, but so that nothing unforeseen happens, there is a well thought-out protection circuit.

Listening Test

We appropriately connected the SP 1.7 decoder/preamp to the 9B SST power amplifier with balanced cables, the DVD player was a Denon Model DVD-A1, and for loudspeakers we used the grandiose KEF XQ ensemble. As usual we began our listening session with the opening sequence from "Gladiator." It was astonishing how the voice of Russel Crowe was able to penetrate "glass clearly" despite the enormous battle turmoil, and at the same time dovetail in place harmonically. Also the swordfight in the arena, permeated by a cluster of audible details was resolved exemplarily by the Bryston combination and built up into an incredible harmonious sound field. The abundantly available muscles made childplay for the Bryston combination when playing "U571." The exploding waterbombs were acoustically reproduced with sheer uncanny vehemence, without submerging the slightest details like crunching metal or the breathing of the crew in a thunderstorm of sound. Finally we were totally enraptured when we played a music DVD, and we almost had the feeling to be "Live at Albert Hall" with Robbie Williams. Tonally, dynamically, and in the area of spatial reproduction, the SP 1.7/9B SST combination can easily compete with every high end Hi-Fi system in two channel operation, and even supersede it. And finally while playing multichannel programs, it becomes quickly apparent that there are no longer reasons for the existence of pure stereo equipment.

Conclusion

The rating that was accorded the old version "Reference Class", remains without any modification. We even go one step further and position the SP 1.7 and 9B SST team soundwise very high up into the top league of high end home video decoders. When perfect sound is the most important argument for the purchase of an AV decoder, and the connection diversity for "normal" requirements is enough, one is indeed very well advised with the Bryston combination. When purchasing an SP 1.7 processor/preamp and an 9B SST power amplifier, one is rewarded with first class quality workmanship including a 20 year warranty, as well as the assurance to be able to update for years to come.

Michael Voigt

Translated from the German by Peter Ullman

We invite you to experience the Bryston SST² Series amplifiers

20 Year Warranty - A Generation of Music