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High end audio combo offers mellow music

Bryston's 4B amplifier and .4B preamp

Canada's Bryston Limited has released an updated, re-engineered version of its classic 4B amplifier. The 4B ST, the new version of what was Bryston's most popular amplifier, is a sweet-sounding performer that's part of the company's new ST series of amplifiers.

Bryston's ST series, claims the company, is a direct result of its constant search for ways to improve the performance, value, and reliability of its products. The enhancements include the use of "gain stage topology" to bring about a lower noise floor. Bryston does this by using low-impedance pathways inside the amp to cut down on resistance and therefore get those pesky little electrons zipping through the wires more efficiently.

This approach is also supposed to reduce the overall distortion of the amp (and we remember the older model 4B as being a pretty darn good performer in its own right, and wish we'd been able to run both generations side by side to compare them).

The company says the refinements show up in performance, with distortion levels of less than "10 parts per million," or less than 0.0009%, which is a pretty impressive spec. Will you actually hear the difference? It probably depends on how much rock n roll you've listened to over the years…

Anyway, a new, proprietary, "Quad-Complementary output section" is featured on the ST series amps (the series is made up of the 3B, 4B, 7B, and 8B), which is supposed to virtually eliminate "aggressive higher harmonic distortion products." Which translates to better sound quality.

Bryston's custom dual toroidal power supplies are claimed to provide precise and focused soundstaging, which means musical instruments sound like they're emanating from the place in which they were recorded, not just some vague place in your listening room. With many "multiple overdubbed" recordings, like your typical rock album, this can be a pretty meaningless thing. However, it's important on live, or live in studio recordings where the musicians are clustered around the microphones; the "soundstaging" is supposed to reproduce this setup and in a good amplifier it really does.

Of course you have to couple this with good speaker for it to really work.

As is proper with a stereo amplifier, it has a separate power supply for each stereo channel, and the amp can be "bridged" (switched into a mono amp for extra power - but of course you then need two amps for stereo instead of one). The Bryston also comes with both balanced and unbalanced, gold plated input connectors.

Bridging the 4B gives you a horrendous amount of power. In normal, stereo mode, the 4B ST cranks out 250 watts per channel into 8 ohms, which is a pretty good starting point. Bridged, however, it jumps to 800 watts into the one channel, also at 8 ohms.

If you use 4 ohm speakers, the 4B'll give you a healthy 400 watts per stereo channel.

Of course, watts per channel power doesn't tell the whole story; 250 watts might sound like a lot more (or a lot less) depending on the amplifier's quality, the efficiency of your speakers, etc. etc. So a good 100 watt amp might give you better sound than a cheap 200 watter (if, indeed, there were such a thing as a cheap 200 watts amp!).

However, when you enter the type of marketplace occupied by Bryston and the other "high end" manufacturers, you're getting quality power, so in cases like this it's pretty safe to believe the specs...

Which means the 4B's 250 watts (we used it on 8 ohm speakers and didn't bridge it), sounds like a million bucks, with a couple of exceptions in which it only sounded like three quarters of a million bucks. Those exceptions were loud rock music, where we found the Bryston a little lacking in low end "ooomph" when reproducing electric bass guitar. If you like peeling the paint from your walls merely by cranking "Live at Leeds" you may want to look elsewhere.

Likewise, this may not be the best amp for your home theatre application, for the same reason. Who wants mellow-sounding explosions?

To be fair, it isn't that the Bryston can't handle rock or movies. We just thought that, on movies and rock music, it didn't quite drive our reference speakers' low end as much as we'd like it to. It needed a little more "punch."

Otherwise the 4B ST was very good.

So if you're not looking for an amp to power your main home theatre speakers, and your musical tastes swing more toward acoustic instruments like a symphony or a jazz combo, you'll probably be very happy with the 4B's performance.

Companion Piece…

We also played with the companion .4B preamplifier from Bryston, a classy and simple to operate unit that's also aimed at the audiophile.

Controls are minimal. As far as knobs are concerned, you only get source switching (CD, tuner, AUX etc.), a balance control, and the volume knob. The front panel also includes buttons for power, low filter, tape monitoring, and muting. That's it. As is normal with high end equipment, there are no tone controls or other methods by which you can "colour" the sound, the theory being that what you want to hear coming out of the system is a completely accurate reproduction of what went in.

You also don't get a remote control, another common shortcoming (if you like having the convenience of a remote) of high end equipment. We like having a remote, because there's no better place from which to adjust the volume, etc. than where you're actually doing your listening. Still, it's something we can live without if there are other benefits to the equipment, like great sound! We'd live without it for the Bryston and its ilk.

Sound of the .4b/4B ST combination is clear, clean, and crisp, as befitting a setup that'll cost you nearly $3000 US. Aside from our concern about the low end, this amp/preamp perform beautifully and, naturally (considering the lack of controls and features), is very easy to use.

And you're buying for a lifetime of use with the Brystons: the company offers a whopping 20 year parts and labour warranty!

Now that's how it should be!

Bryston 4B amplifier specifications:

Power: 250 Watts per channel, 8 ohms
400 Watts per channel, 4 ohms
800 Watts, mono, bridged
Distortion: Less than 0.007% from 20 Hz to 20 kHz at 250 watts, IM or THD
Noise: >106 dB below full output
Features: stereo/mono switch, regulated power supplies to all voltage gain stages, gold plated input and output connectors, switchable balanced XLR-1/4 inch and RCA unbalanced inputs.
Dimensions: 19 x 5.25 x 15.5 inches, weight 42 lb.

Bryston .4B preamp specifications:

Frequency response: 20 Hz to 20 kHz +/- 5 mB
IM or THD: 0.005%
High level sensitivity: 500 mV
Noise (high level): -95 dBA, referred to an input level of 500 mV @ 1 kHz
Dimensions: 19 x 1.75 x 8 inches, weight 7 lb..

Manufacturer: Bryston Limited, Peterborough, Ontario, Canada.

(TechnoFILE's test equipment was provided by Loyalty Sound of Calgary, Alberta)


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Updated February 3, 2021