Analogue Solid State Class A Preamplifier
Bryston have a reputation for making premium amplifiers, have been in business for 35 years, and have built up a name synonymous with quality. Oddly for a HiFi brand, their origins were in the medical component industry. The Bryston BP173 (BP17 cubed) sits in the range between the BP6 and BP26 models, which is a class A Preamplifier running its current constantly and the peaks and troughs of the audio signal. Whereas with the c.£5000 BP26 you require the c.£1,900 MPS2 power supply, the BP173 runs off the mains via a standard IEC connection, which is handy to avoid costs of separate power supplies.
It’s more a functional looking preamplifier than other sexed up looking preamps at this price. In this understated way it gets you thinking its sound quality could be much better than you might expect considering the reputation of this brand. The quirky Bryston logo is smartly machined on the front aluminium face place. This can be either silver or black and in a slightly oversized width of 17 inches or much more oversized 19 inches, which isn’t rack mountable.
Bryston say this preamplifier features their patented ‘Salomie’ buffer circuit which reduces distortion at the input stage thus reducing distortion of the entire audio system.
You can spec it to include an internal DAC with two S/PDIF and two optical inputs, supporting up to 24bit 96khz PCM and/or a MM/MC phono stage. It comes with the weighty machined aluminium BR2 remote, which is no longer a £500 option. This remotes motion sensing remote backlighting can be turned on and off by inputting remote codes into it. It’s definitely one of the nicest most solid remotes on the market. The large volume dial on the front face plate is typically motor controlled by the BR2. You do get balance control which is often omitted on preamplifiers in this class, plus there is a headphone amp/output too.
The BP173 has the full suite of inputs and outputs which you might expect for a preamplifier at this price. There are two XLR inputs for connecting up balanced CD players and DACs for instance, 2 XLR variable (volume) outputs to connect up power amp(s) and similarly one set of single ended RCA variable outputs. Five sets of single ended RCA inputs allow connection to source components. If you have a Bryston DAC fitted one set of RCA inputs doubles up as digital coaxial inputs.
You also get a fixed volume RCA output for connecting up recording devices and two trigger outputs, via 3.5mm sockets, to either turn on compatible power amp(s) as the unit is turned on. Using the other trigger output, to turn on another component with a source input change and programmed with the remote. If your power amps have the RS232 serial connectors and you aren’t a dab hand at making up trigger cables yourself, you’ll need to get someone to make these up as they are not commercially available. Helpfully Bryston provided a diagram (as below) to assist in wiring to my Cyrus amps and I found computer shops were best placed to help, if you don’t know any HiFi hobbyists who could help with such a cable.
A huge feather in the cap of purchasing this preamplifier is Bryston’s unusually long 20 year transferable warranty which should limit depreciation and keep resale prices high. It’s very clear Bryston have a lot of confidence with this product with this warranty.
Refinement in spades
I compared the BP173 to my own Cyrus DAC XP Signature preamplifier/DAC (£3000) with its PSX-R power supply (£500), using my Cyrus Mono X200 Signature power amplifiers and PMC Twenty5 23 speakers. Also a £6000ish Audio Research LS26 tube/solid state preamplifier which is not a current model but it gave a meaningful comparison. I also used my Chord Qutest DAC in the comparison (with a MCRU Qutest linear power supply) and my Innuos Zenith mark 2 source over USB to the Qutest. Also a 2 Qute DAC.
One thing that that is immediately obvious is how refined the Bryston sound is and in occupying a neutral to slightly tonally warm rich presentation. Whereas the Cyrus gets its presentation with a shininess in the treble, the BP173 takes neutral resolution in its stride. It presents the music with so much naturalness and what seems to be little distortion, that the music seems much more giving of natural timbre. It’s therefore very realistic and particularly with acoustic music. But no other word sticks in your mind when you play music through it other than ‘refinement’.
It’s no slouch for speed and easily keeps up with the pace of my Cyrus preamplifier and whilst initially I was thinking that with its more neutral tonal presentation it might present an impression of being less capable in this regard, and dynamically too, this was certainly dispelled after a longer listen.
The BP173 presents a ‘purist hifi sound’ in the sense of its neutral tonality and refinement which makes most of the source. James Tanner, VP of marketing at Bryston, informed me that they have always attempted to build the most linear amplifiers available so they try and get out of the way of the resulting sound to make it more a function of the source gear /DAC etc. With the known smooth tonal qualities of my Innuos, the BP173 does very much reflect the source which is noticed subtly but no less obviously, when changing to my Cyrus Cd-t cd transport. This is much more marked than with the Cyrus and other preamplifiers/DACs I’ve had on my system recently too such as the Mytek Brooklyn DAC/pre. The Audio Research LS26 tube/solid state hybrid preamplifier, whilst having a very wide soundstage and clean sound, often typical of amplifiers of this design, wasn’t as reflective of the source like the BP173. Also it wasn’t as tonally refined and balanced, but was more like the sound signature of Cyrus.
Playing a very good recording of The Carpenters ‘Solitaire’ in DSD I have recently come across, this refinement and neutrality does mean Karen Carpenter’s vocal doesn’t quite have the same raw edginess or airiness of a system which presents with a touch more treble like Cyrus, which often provides ‘in your face’ realism. But these are matters of taste mainly and not of any concern as HiFi is always a balancing act between tone and how easy it is to live with on its treble abilities. Too much treble and it’s irksome, not enough and detail can’t shine. However the BP173 is perfect in this sense and there is no doubt that using the Bryston in my system with this refinement on offer, makes listening to music less tiring at higher volume and more involving at normal levels too with the aforementioned qualities. The Bryston is also very good with soundstage and imaging and presents a big involving sound, so overall it’s a much more appealing sound.
Another thing you notice with this preamplifier as a major quality is its bass depth and slam – it just goes further than you’d expect and it’s accurate with bass too. There is no bloat to the bass at all and again it’s very real.
This Bryston is very much a ‘keeper’ in a system because of its all round capabilities, its neutrality, and its qualities must surely make it one of the best preamplifiers you can get at this price and nearing best reference quality.
I’ve also heard the BP173 with a system comprising Vienna Acoustics ‘The Kiss’ speakers, a Chord Electronics DAVE DAC, my Innuos Zenith, as well as the matching Bryston 4B3 power amp. It’s not a system for which meaningful extrapolation can be made for the benefit of the review here, being a system I’m not familiar with. However the overall combination was still one of refinement and neutral balance, plus significant power from the 4B3.
I wonder whether Bryston have given consideration to a more elaborate front milled face plate to improve on design and the desirability of the product. HiFi undeniably does sell on its looks and the BP173 is plain looking, but that said the basic design does have its own simplistic appeal I suppose.
Comparisons of the BP26 with MPS2 power supply to the BP173 have been made. I note some authorities have voiced a preference for the BP173, and some the opposite. If you are considering this preamplifier it would be worthwhile doing a comparison as relatively speaking the prices are not too far apart and good deals can be had buying the BP26/MPS2 as a combination. James describes the BP173 as more neutral but ‘distant’ sounding and also that the BP26/MPS2 is a bit more punchy in the mid bass.
In my opinion it’s an extremely good preamplifier and I can’t recommend it enough and its understated looks definitely do defy its sound quality. An absolutely tremendous product – I want one!
- Fully discrete Class A analogue circuit
- Patented ‘Salomie’ circuit
- Independent power supply and ground paths for analogue and digital circuits
- Relay switching on all inputs
- Inputs : 2 X XLR Balanced, 5 x Single ended pairs (RCA)
- Outputs : 2 x XLR balanced, 2 x single ended pairs, 1/4inch headphone jack
- Control : RS232 trigger, IR socket
- BR2 remote control included
- £4500 (black/silver)
- MM phono (c£699)
- MC/MM phono (c£1399)
- DAC (c£1499)
PMC (UK distributor)
Tel ; (01767) 686300