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Bryston BP-25 Preamplifier
James T. Frane
Audiophile Voice
I first discovered the sound and quality of
Bryston at the Hi-Fi '97 show and I later reviewed their integrated
amplifier. Bryston is a Canadian Company that has been making
amplifiers since 1974. During that time they have carved out a
reputation for very high quality sound and hardware. Their current
line includes several power amps, an integrated amp, and two basic
preamp models: the BP-20 without remote control, and the BP 25
with remote control. Both preamps are also available with an optional
phono preamp section for either moving magnet or moving coil cartridges.
Bryston lists the following preamp improvements
over their previous units: Intermodulation distortion has been
reduced; input-to-input crosstalk is essentially nonexistent;
channel-to-channel interaction has been improved; components plug
directly into glass-epoxy circuit boards, eliminating variations
in signal travel and wire interaction; signal switching and connections
utilize heavy gold plating to provide long-term trouble-free connections;
a ground plane has been incorporated to further reduce crosstalk
and noise throughout the internal circuitry, and the power supply
is mounted externally to eliminate the potential for noise and
interference from that source.
The BP-25's on-off switch is on the front of
the separate power supply, which is connected to the preamp by
a cord about two feet long. A green LED shows when the unit is
on. The power unit is about 4½ inches wide x 2 inches high
x 7-5/8 inches deep and can sit on top of, next to, or some distance
from, the BP-25.
The steel chassis and sleek cabinet are designed
to shield against electromagnetic interference. Only 1.75 high
x 17 inches wide x 11 inches deep, the unit weighs in at a hefty
17.5 pounds. The controls on the front of the preamp, from left
to right, are tape / source switch, mono / stereo switch, a rotary
source control, balance control with center detent, motorized
volume control, absolute polarity switch, and a mute switch. The
source control positions are labeled "Bal 1" and "2,"
"Phono," "CD," "Tuner," "Video,"
and "Disc". Changing polarity changes the LED, located
between polarity and mute switches, from green to yellow. A quarter-inch
headphone jack is just above the LED. When a headphone plug is
inserted into the jack, the speakers are automatically silenced.
The mono feature is handy for speaker setup, as properly placed
and operating stereo speakers fed a mono signal will have an image
centered between them.
The back panel has both balanced XLR and unbalanced
RCA-type phono connectors. The power connection from the external
power transformer is at far left followed by a pair of XLR connectors.
The gold-plated phono jacks are: Preamp "out" (two sets
for driving two power amplifiers without a Y-connector), "To"
and "From" tape jacks, "Disc," "Video,"
"Tuner," "CD," and "Phono" inputs.
The latter is for an outboard phono preamp on the BP-20 or the
BP-25 without built-in phono preamp. Next are two pair of balanced
output XLR connectors. A surround sound or other processor, cassette
tape deck, or video tape recorder can be connected to the tape
loop.
A 12-volt a.c. / d.c. screw-terminal connector
on the rear of the power supply provides power amplifier on-off
control when used in conjunction with the remote start feature
available on Bryston and some other amplifiers. The BP-25 is shipped
suspended in a strong, flexible plastic foam within a large heavy-weight
cardboard carton. This preamp is available in silver or black,
and with an optional wide front panel for rack mounting.
Bryston's 20-year parts and labor warranty against
manufacturing defects is, so far as I'm aware, the longest in
the industry. The warranty benefits not only the original buyer,
but subsequent ones as well, and includes return shipping. James
Tanner, vice president of Bryston, related to me some time ago
that he had suggested the warranty extension to 20 years. Repairs
were very rarely needed, Bryston was not charging customers for
repairs, and publicizing the confidence Bryston had gained in
their products through experience seemed a good idea.
The five-page owner's manual is sufficient for
an experienced person, but I would have liked more detail. The
more common industry practice of showing wiring connection diagrams
between the preamp and other pieces of equipment might be helpful
to many users.
The remote control operates over a wide angle,
and it has a sturdy, solid, and luxurious feel, reinforcing the
sense of quality. It appears to have been machined from a solid
block of metal. It has momentary buttons for volume, mute, and
absolute polarity inversion. The mute button completely silences
the output, but does not affect the output to a tape deck. I found
that the phase inversion can improve the sound when the absolute
phase has been reversed in the chain from mike to speakers from
that of the live performance. With phase reversal, the speaker
cone moves inward on a note, when it would have moved outward
if it were a direct feed from the original. Close control of the
BP-25 volume was easy. "Mute" turned off sound completely.
Listening
Introducing the BP-25 into my system made the
largest improvement I have experienced in a very long time. The
net effect was to make the music more like live. The sound source
seemed to become independent of the speakers. Where the music
could float between and to the sides of the speakers with the
Carver, added dimensions appeared with the BP-25. The depth became
more lifelike, with performers at different distances from me,
and the back wall was no hindrance. The sound would sometimes
start several feet past that wall. It also extended farther to
the sides, and could be suspended between and in front of the
speakers. The increased ambiance and three dimensionality, particularly
with live recordings and others that were well miked and recorded,
were superb. During the course of this audition, I compared the
sound through the BP-25 with that of the CD player directly driving
the power amp. I am convinced the Bryston does not add artificial
enhancement, but that it lets the music through intact and without
degradation. I listened to tuner, tape, CD, and LPs through the
BP-25, and found it consistently sounded freer and more open than
the Carver. I took care to match the levels as exactly as I could
within the limits of my digital sound-level meter. The Carver
has done well, having been on every day that I am home, since
1990. It was a very satisfying unit for its time, and a marked
improvement over the Denon it replaced, but it has definitely
had its day. That it has been bested with improved accuracy and
performance is very clear. "Mrs. Robinson" from Simon
and Garfunkel's Greatest Hits (Columbia CK 31350) is a performance
before a live audience. Besides the feeling of being there, one
very distinct difference was that the cymbals were emphasized
through the Carver and were relatively strident and edgy. With
the BP-25, they were detailed, more musical, and in balance with
the rest of the instruments without being harsh. They had the
proper metallic shimmer, but lost the aspect of "breaking
glass." Julie London's vocal recordings portray well the
ambiance of the recording venue, and many have full orchestra
backup. These gained so much realism that it was easy to imagine
the performance in front of me. Jazz and classical performances,
from solos to combos or quartets to full orchestrations, were
involving and pleasurable, as were big band records. Old rock
and roll songs came to life, and good and bad mixes were easily
identifiable. All of the rhythm and dynamics of a good recording
were there. I was drawn into performances many times, as they
were so musical and alive, with appropriate depth and perspective.
Voices sounded natural through the BP-25 and instrument timbres
were right. The recording spaces were recreated with a three-dimensional
presence. There was no audible crosstalk through the Bryston unless
the volume control was nearly to its maximum setting, a situation
that would not occur in use as relatively little movement of the
volume control easily drove the power amp to live listening levels.
There was no hum or other electronic noise, nor any mechanical
sound from the BP-25. You may think this an unusual observation
to make, but far too many times, I have experienced these artifacts
with preamps that would have otherwise been very desirable to
own.
Conclusion
Often the changes wrought by changing electronics
are very subtle, but sometimes they are readily apparent. The
Bryston BP-25 made an outstanding improvement - that extra step
closer to reality one searches for. My standard of reference comprises
the many live music performances I regularly attend. The music
through my system isn't live, but it is very good. I am an engineer
and I don't believe exaggerations accurately convey information,
so I would not say the BP-25, or any other unit, is the best.
My experience shows that the BP-25 is as good as any I have heard,
in my system or others. It is not inexpensive, but its performance
makes it a component of exceptional value. There are many very
good preamps available, for a wide variety of prices. I recommend
you audition this one if you're in the market for a preamp and
it falls within your budget range.
Notes
Bryston BP-25 Preamplifier,
Bryston, Ltd.,
677 Neal Dr.,
Peterborough, Ontario
K9J 7V4,
Canada.
Selected specifications:
Frequency response, 20 Hz to 20 kHz +1 -0.05 dB; IM or THD, less
than 0.0025 per cent at 3 volts output.
Associated Equipment Parasound HCA 1000A power amp, Carver CT-17 preamp-tuner,
Parasound P/PH-100 phono preamp, Denon TU-767 tuner, Thorens TD320
Mark III turntable with Grado Prestige Red cartridge, Aiwa AD
F800 cassette deck, and Sony XA20ES CD player, Mach 1 Model M-Two
speakers with NHT SW3 subwoofers run in dual mono and separately
driven by an NHT SA-3 power amp with integral electronic crossover.
The Mach Ones were run full range. I also used Revel F30 speakers
with the BP-25. Interconnects were by Gotham, WireWorld, Mach
1, and Monster Cable, speaker cables were Mach 1 to the NHT subwoofers,
and Kimber 4PR to the Mach 1s and Revel F30s. A Radio Shack digital
sound-level meter to match levels.
We invite you to experience the Bryston SST2 Series amplifiers
20 Year Warranty - A Generation of Music
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