Bryston Rocks

by David Berriman

It’s now a few years since I first encountered the Canadian Bryston brand: I reviewed the Bryston 3BNRB power amp and BP5 pre-amplifier in Oct ‘95. Besides being built like proverbial brick outhouses and made to last (with a 20-year guarantee thrown in free!) they sounded rather well. Whatever they may have seemed to lack in hi-fl fireworks they certainly made up for with overall control, definition, analysis and listenability.

For a long time, when other amplifiers came into the system for review, I’d find it came as a relief when the Brystons were wired back in. However, after a while, I became aware that I was no longer always so delighted when they were re-connected. Long-term acoustic memory is as strange thing - and with two house moves in between it is hard to tell whether it was the amplifier which had changed, my perception of it, or simply the radically different room acoustics with which my system now has to deal. My home listening room is now rather brighter and less forgiving than before, while my other listening area is noticeably warmer, and possibly more neutral. Anyway, when Keith Tonge of PMC told me about the 4BST power amp (more powerful than the 3B NRB) and BP20/BP25 pre- amplifier, claimed to outperform the old models substantially, I jumped at the chance of reviewing them. Especially after the ATC SIA2-150 amp, which wowed me so effectively [HFN/RR, Sept ‘99]. As Bryston’s philosophy is influenced by a similar studio/domestic design ethic, the review would be all the more interesting.

INSIDE THE BP20
Outwardly, the new pre- and power amp are very similar to the old models, finished as they are in the same anodised, finished black aluminium. The standards of construction inside and out are, as you'd expect, similarly high. The BP20 pre-amp under review costs £1200 and is a line-level only device. The alternative versions, BP25P and BP25MC (£1475 and £1800 respectively), are both for lovers of the black round stuff, each containing an RIAA phono input stage comprising all discrete transistors, and offering either m-rn or m-c input (m-c, with higher gain switchable from the front panel).

The slim rear panel of the BP-25 is wedged full of sockets. There are five pairs of RCA ‘phono’ inputs (unbalanced), a pair of RCA-type tape inputs and outputs plus two pairs of balanced XLR inputs. Outputs comprise two pairs of unbalanced RCA phonos and one pair of XLRs (balanced). These balanced connections are of course mainly intended for pro-audio applications, where they give improved isolation from hum and interference, particularly over long runs of cable; but they can also bring benefits to home hi-fl. Three- pin connectors provide remote on/off control of the pre-amp.

Inside, a single printed circuit board carries virtually all the components: motorised ALPS volume control, wafer switches and discrete amplification circuitry, plus power supply rectification and smoothing. Great care has been taken with the layout in both pre- and power amp to minimise the signal paths and reduce distortion. This might sound like audiophile ethos applied to pro audio, but in reality it’s just good design.

The front panel sports rotary input selector, balance and volume, with miniature toggle switches for tape, mono/stereo, mute and polarity inversion. In addition, the pre-amp is also supplied with a chunky solid aluminium cased infra-red remote, which rather neatly allows control over just volume (via the motorised pot), muting and phase inversion. I must say I liked this simple unit, which is really all that’s needed. Power comes via a separate outboard transformer, which keeps hum away from low-level circuits, and plugs into a socket on the rear panel.

4BST POWER AMPLIFIER
Big and chunky like the 3BNRB, the 4BST wears its heatsinks and power-output transistors to the sides and a large central on/off switch on its front panel. Indeed, apart from the two grab handles, that’s almost all you’ll see here. I write almost, because just above the power switch are two multi- coloured LEDs. Green indicates normal operation, yellow shows clipping is approaching, while red indicates clipping is present. As the instructions warn, green and yellow are OK, but flashing red is not good news for loudspeakers, which can easily be damaged by clipped music signals. At least the user can back off the volume when this is visible. Red flashes during power-up and down are not a problem.

Around the back, there are two balanced input sockets which take both XLRs and professional jack plugs, plus two RCA (unbalanced) phono sockets for good measure. There’s a switch to select balanced or unbalanced input modes, a ground-lift switch and a stereo/bridged mode toggle, which converts the amplifier from a 250W rated stereo to an 800W-rated mono amplifier. Inside, the two electrically-separate power supplies are mounted in the centre, with the power amp circuits to each side. Two large toroidal transformers and eight (four per channel) large smoothing capacitors grace the power supply section. With no commonality except the casing, the 4BST is truly dual-mono, and so should reap the benefits of very good channel separation.

THE SOUND
As soon as the pre- and power amplifier arrived, they were connected together with the balanced XLR/XLR interconnects supplied, and powered up. As with any piece of electronics they took a while to bed in. My initial impressions where of just a slight but definite improvement over the old pre-/power. As the new pairing warmed up and bedded in, the sound really improved quite noticeably, becoming both smoother and more open. The new combination really was substantially better - obvious even without a direct comparison. My annoyance with the old pair - a certain grainy brittleness - was all but banished, while the bass - which was already superb in its gut-plumbing depth and power - now took on even greater shape, texture and definition. With the old models, one could easily separate bass instruments in the mix, but the new pair were better still, with the old bloom replaced by a new strength, definition and confidence.

During the bedding-in period of the review pair, the old power and pre-amp were dispatched for a thorough check-over and a general overhaul to original spec, just in case anything had changed. On their return they were auditioned again. The sound had indeed improved, sounding smoother and easier, but were still no match for the (admittedly more powerful) 4BST power amp and the BP25 pre. Now that these had run-in, bedded-in or warmed-up (whichever term you prefer!), the 4BST and BP25 were really singing. The Bryston power amps do become nicely warm in use, even when just ticking over, and don’t fully come on song until they have been playing music for an hour or so. To me there is something comforting about amplifiers which run warm, a feeling that they are more likely to stabilise to satisfactory working bias currents which should minimise distortion at all output levels. I never totally trust power amplifiers which run really cool until thrashed, as the semiconductor temperatures will fluctuate more than those which are not only permanently warm but are also turned on for low-level signals.

Compared to the original amplifiers, even in their refurbished state, the bass of the new review pair was more controlled, treble sweeter and more expressive and the mid just cleaner and clearer. The overall definition and instrumental detail were excellent. In particular, instruments or vocals way down in the mix were audible with absolute clarity, whereas with many amplifiers these were obscured or masked. There seemed to be new layers of resolution across the whole range, without resorting to glare. Treble was crisp and detailed without harshness, but was not euphonically smoothed. There’s no rose-tinted glossing-over with the Brystons. If there’s an acidic edge in the recording, then you’ll hear it. It’s an overworked cliche, but the Brystons are musically expressive; all that reproduced detail really does reveal how musicians were playing when the recording was made. They really did remind me of the excellent ATC SA150 integrated.

The Brystons handled all types of music with equanimity. Playing ‘Part of the Process’ from Morcheeba’s Big Calm, showed just how good the BP25 and 4BST are. Sky Edwards’ sultry voice, twanging lap steel guitar, throbbing synth, slapping bass drum machine and deep bass guitar were all handled superbly: the high-frequency upper- harmonic synth sounds on this track never descended into harsh audible distortion, as can be the case.

Another example was the Eurythmics’ ‘Missionary Man’. This fairly exploded across the room and provided a real sense of a performance, rather than mere reproduction. Having heard Annie and Dave at Wembley the night before, it was something of a surprise to hear the home system do so well! I’m convinced that the Brystons take most of the credit. They seem to imbue music with a rightness and naturalness; and not just in tonality - it’s down to expressiveness and communication with almost a sleight-of hand. Just as you are trying to analyse, to figure out the sound, you realise you’ve been enjoying the music all along. Enough said? With all their tracks, the trick was the same: a giant slab of well-sorted sound; complete with rough edges, the usual distortion heard with electric music, but never exaggerated.

Classical and jazz were treated the same way too. Miles Davis’s Porgy and Bess [Columbia/Legacy CK 65141, 20-bit re-mastered] was just one example that shows an old, slightly bright, recording, and mesmerising musicianship, done proud. I could go on about depth and stereo image, but the Bryston had all that: The Brystons’ subjective low-level resolution almost guaranteed the reproduction of depth and a sense of genuine acoustics with classical music in real halls, in the same way that they generated an almost visceral response from good studio- produced music. In the allegro from Weber’s clarinet concerto [Musical Fidelity], Anthony Michaelson’s clarinet sang out clearly over the accompanying clearly defined violin, viola and double bass: and the 300 year old Testore cello sounded rich and vibrant.

Sometimes recordings surprise. Take Lou Reed’s landmark, Transformer. As it dates from 1972, you wouldn’t expect much of recorded quality, yet this David Bowie/Mick Ronson production is full of layers. It’s been so carefully put together and the Brystons show every bit of it. In ‘Walk on the Wild Side’, the bass and drum are mixed together to emphasize the bass slap, but you can hear both clearly. Lou’s voice is rock-steady and when ‘the coloured girls sing do, de-do, de-do, de-do-de-do, do...’ the way they fade from the background to the fore is just magical.

Perhaps that’s why importer PMC sells so many to recording studios, film and AV post- processing suits. Perhaps that’s why music-loving hi-fl buyers and, more recently, home cinema enthusiasts are said to be buying Brystons: the combination of pure musical sound and awesome power could be ideal for music lovers who wish to use their home cinema systems for music too. So, there you have the Brystons, but are they Pro Audio or hi-fi? I can’t make out whether Bryston is a Pro Audio product which works on an audiophile level, or vice versa and why. Perhaps it’s that Bryston designers, freed from the need to impress hi-fl buyers in shops simply strive to make naturally analytical products, but in the final analysis, does it really matter? They’re certainly not cheap but sound (if sound is the right word for products with so little sound of their own) excellent and last for years. I enjoyed my spell with the new models, and can only suggest that you listen to them - if you want to hear what’s really on your discs.