A Fine Line: The BB100

hfnvintageKen Kessler on Bill Beard's new line-level-only integrated valve amplifier

Manufacturers should not be criticised for responding to changing tastes. CD has forever changed the face of hi-fi, so all you're doing when you mourn the passage of the phono stage is increase the value of shares in sackcloth and ashes. Instead, be thankful that the companies in the high-end are intent on making the best line-stage amplifiers they can design. What you use for a phono section can be either your existing, pre-CD preamp or an outboard phono section. With this in mind. Bill Beard has launched an all-valve, line-level-only integrated amplifier, the first product to bear his new company's name.

Soldiering On
Bill left Beard Audio (which will continue under new ownership with the existing range) to form British Built Audiophile Products. Although the new units will differ in many ways from the designs he produced over the past 12 years, all will continue in the tradition established by such classics as the P100 amplifier. The amplifiers produced by British Built Audiophile Products (BBAP for short) promise to offer superb sound and build quality at sensible prices. If the BB100 is indicative of what may follow, we might at last see a full range of real-world, UK-made tube electronics.

The BB100 is a hefty, single-chassis item designed to bring out the hi-fi casualty in all of us. With or without the protective cage in place, the BB100 shouts 'valves!' because you can see all 18 glowing away. This conservatively-rated 2x 50-watter derives its power from three parallel 'push-pull' pairs of EL84s per channel, presenting a very low (2.6kohm) output impedance to the output transformer for easier driving conditions.

The valves are lined up like soldiers behind a complement of four ECC81s and two ECC82s in the preamp section. Each channel in the preamp employs one ECC81 in the driver stage, another '81 as a phase splitter and the '82 as a cathode follower. The heaters for every valve in the BB100 are fully DC regulated.


To prevent paranoia among those of you who think that valves are a recipe for ensuring your local repairman's fiscal health, the BB100 has been designed to make valve amp ownership a set-and-forget exercise. The valves are common, inexpensive and durable while an LED glows when the bottle ages, by measuring the amount of current drawn by each valve. A brightly- glowing LED means that you remove the valve and fit a replacement. The BB100 operates with a mix of grid and cathode biasing to preclude the need for bias adjustments.

Dual Mono
On a personal note, I find all the fear of adjusting bias to be excessive and unnecessary. If I can do it, anyone can. On the other hand, it's been explained to me by more than one manufacturer that no matter how clear the instructions, someone is bound to set the bias incorrectly and destroy the odd tube.

The only reason I mention this, since most would willingly trade the inconvenience of manual adjust for automatic biasing, is the trade-off between cathode and grid bias. With cathode biasing you get sweet 'old valve' sound and automatic biasing, whereas grid bias produced a tight, crisp bass, more appealing to modern ears while requiring manual adjustment. BBAP has employed a hybrid of the two which works beautifully, so I suppose that in reality there's little sonic justification left for grid-only biasing.

The BB100 is pretty much dual-mono throughout, with the only shared aspects of the design being the single-piece, double-wound mains transformer and a master gain control. The latter, however, is a double-track knob, so the 'mono-ing' is mechanical rather than electronic.

With the cage removed and the BB100 viewed with the controls facing you, the back third of the amp's top surface contains the mains transformer flanked by the separate output transformers. These are wound and constructed to 1% tolerance and are described as a '35% ultra-linear tap design', understressed to need less feedback.

Designer Goodies
The output section also employs 1300µF reservoir capacitors for each channel. The driver stage is a high current design with its own dedicated regulated DC power supply hosting 4700µF per channel.

Despite its sensible pricing, the BB100 is brimming with designer goodies, of which 80% are purpose-made to BBAP specifications. All capacitors are either polypropylene types or low ESR electrolytics, mounted on a double-sided PCB employing 2oz copper tracks.

For easier servicing of the amp, the main tracks and components are positioned on one side of the board. Meanwhile, internal wiring consists of computer data transmission cable, a solid core type made from silver-plated copper, with separate star earthing for each channel.

At the back of the amplifier are high-quality gold-plated input sockets for CD, tape in and out, tuner, 'aux' and 'external phono', two fuse holders, the on-off switch and Michell binding posts which accept just about any connector you'd care to employ short of a two-pin DIN speaker plug! Crowded it may be, but the front panel reaffirms the design's minimalism.