Reprint from Sept.-Oct. 2001

BRYSTON SP-1 AND 9B-ST HOME THEATRE PROCESSOR AND POWER AMPLIFIER

by Alvin Gold

I first encountered this home theatre processor and five-channel power amplifier as part of a multiple review of mid- and high-end processors and power amps. To cut a long story short, it turned out to be head and shoulders above the rest on most counts, and the rest in this case included some very illustrious machinery indeed.

What marks out the Bryston? Quite simply, the SP-1 processor starts life, as a 5.1 channel version of one of Bryston's top of the range stereo preamplifiers, the BP-25, and the 9B-ST is essentially a five-channel audiophile-quality power amplifier. Of course, you may object that many home cinema amplifiers are developed in a very similar way from audiophile roots, but this is rarely the case in practice, for two reasons. First, most home cinema processors are extensively digital under the skin, which is par for the course given the complexity of the tasks it is required to do. The power amplifiers can be much closer to standard audiophile practice than the processor, but all too often the damage has already been done by the time the signal appears at the power amplifier input. This isn't so here because the basic signal topology of the SP-1 is that of a particularly good preamplifier, with the simplest yet best-endowed circuit that Bryston knows how to build.

The other reason is even more obvious. Bryston has gone the extra mile in stripping out facilities from the SP-1 that are unnecessary and which are known to damage sound quality. The most startling omission, especially from a processor from North America, is any form of video switching. The Bryston handles only audio signals, and given that the US doesn't use the European SCART interface, which is one of the only viable alternatives to video signal switching by a home theatre preamp, there may be problems configuring complex systems, though the Bryston can be used in tandem with external third-party video switchers. The essential simplicity of the SP-1 is maintained in other ways, too. In stereo mode, the processor operates entirely in the analogue domain, bypassing all AID, DIA and digital processing stages.

The processor can handle Dolby Digital and DTS data, plus Dolby Pro Logic (but not DPL II at the time of testing), plus various DSP acoustic modes. Full THX Ultra certification is also part of the package. Unusually, the processor and power amplifier can be linked together using balanced connections, the power amplifier even including 6.3mm jack inserts let into the XLR sockets, which will help it feel at home in studio surroundings

The balanced interface is there to take advantage of the internal topography of the amplifier and processor, but the idea has not been extended to catering for balanced source components. Other relevant features include four electrical and two optical digital inputs, six line level analogue inputs, a simple but chunky backlit remote control and computer and remote trigger interfaces which will be useful when installing firmware updates and for integrating into multi-room systems. The power amplifier is rated at 120W/ch into 8 Ohms, or 200 W/ch into 4 Ohms, and the 9B-ST consists of five entirely self-contained power amplifier modules, each with its own power transformer. A 20-year guarantee is offered.

The specification is unexceptional, but sound quality is really quite exciting. At its best in stereo, with all multi-channel sound options and decoding bypassed, the system is bold and informative, and well up to the standards of the better audiophile components in a similar price area. Switched to multi-channel mode, which invokes the digital processing, some degradation is audible, but surprisingly modest in extent. The result is arguably the best compromise yet between home cinema and high fidelity. There are some very exactly designed home cinema processors and power amplifiers that are intended to deliver musically, for example from such companies as Theta in the States and TAG McLaren in Europe, but none that I know tilts the balance so firmly in favour of the audiophile principally interested in two-channel replay.

In fact, the Bryston combination offers a thoroughly credible sense of image space and focus, the bass has tremendously solid reach and projection, while treble detail is clean and unexaggerated, and entirely free from grain. Although multi-channel operation introduces some of the undesirable side effects only too familiar from other home cinema electronics, the masking effect of having several channels operating simultaneously tends to conceal the evidence, in much the same way that stereo has for many years been known to be more forgiving than mono. The one-word sum up: superb.

We invite you to experience the Bryston SST² Series amplifiers

20 Year Warranty - A Generation of Music