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Bel BD-80 Digital Delay | |
Article from Home & Studio Recording, July 1984 |
In addition to the common time delay effects, the Bel BD-80 can sample and store up to 16 seconds of sound which may be triggered from a sequencer or drum machine; external voltage control of the sampled sound's pitch also being possible.
As the photograph clearly shows, all the standard DDL controls are provided with the addition of a few extras.
Phase switches are fitted which enable the delay and feedback paths to be inverted, enabling the colouration of short delay time effects to be further modified, whilst a 'delay times two' (x2) switch allows the delay time to be doubled at the expense of reduced bandwidth (16kHz on x1 and 8kHz on x2).
The pitch control allows stored sounds to be fine tuned, control of this parameter also being possible by means of an external control voltage applied to the rear panel ¼" jack CV socket, thus making keyboard control of stored sounds feasible.
The delay time is set by means of the standard up/down/fast pushbuttons and the displayed time also applies to the length of stored sound when used in the sampling mode.
Sampling is achieved by using the 'Sync' button followed by the Start/Stop button which triggers the recording sequence. Depressing the 'Hold' button locks this sound into memory and this may then be triggered at will by further use of the Start/Stop button or by the application of a trigger pulse to the Trigger input jack.
By shortening the delay time, a new sound may be made to replace part of the original 'frozen' sound and by using this editing technique, complex bursts of sound may be built up and subsequently retriggered.
The 2U (3¾") high rack-mounting design is orthodox but very neatly implemented, the black, white and blue panel lending a distinctive appearance to the product.
Internally, the PCB construction is very tidy, all the ICs being mounted in sockets and the extra memory cards vertically mounted, fitting into sockets on the main PCB.
The delay line is easy to use, the input level being set by means of the input gain control and the subsequent level being monitored by means of the four segment LED meter.
A line level input is required to drive this device and so it is not possible to process microphone or instrument inputs directly, but then this unit is aimed at professional users who would undoubtedly use it in conjunction with a mixer.
Storing of sounds was easily achieved by following the comprehensive instructions in the handbook, and these were then retriggered by means of a Roland TR606 trigger output. Triggering was also possible from the drum machines' voice output providing that the level was kept high.
The editing technique outlined in the handbook enabled composite samples of sound to be assembled and these could be varied in pitch by means of the pitch control or by operating the x2 button enabling a one octave change to be directly implemented.
Chorus and flanging effects were easily achieved by using modulation in conjunction with a short delay time (10-25ms), and the phase switch, which inverts the feedback signal, provides further variations in colouration, particularly when flanging effects are being produced.
Subjectively, the background noise was very low, increasing noticeably only when flanging effects with heavy feedback were being generated. This is not a fault but a fundamental side-effect produced by the high level of feedback required to produce a strong effect.
This machine handles all the standard delay effects with ease, the chorus and flange sounds being bright and deep, but it is the long memory and storage capability of the unit that will be of most interest to potential buyers, I suspect.
The maximum delay capability of 16 seconds, or even 8 seconds at full bandwidth, is a very long time, and I would guess that the basic 2 seconds of memory will be more than ample for most users, many of whom will only want to sample percussive sounds which have a relatively short duration anyway.
The BD-80 is not a cheap machine at an RRP of £690 (2047ms delay cards £230 extra), but it will do just about anything that you could reasonably ask of a delay unit and it will do it well.
A dynamic range of 90dB means that the unit should be at home in the most sophisticated studio surroundings and the fact that it is British should mean that spares and service are readily available.
Whether you can justify spending this amount of money on a delay unit will depend very much on the application that you have in mind but, if the sampling facility is what really interests you, there isn't a great deal of choice in this price range and you would do well to give it a try.
Remember though, that the basic price includes only the 2047ms of memory and that it will cost you nearly £1400 to buy the BD-80 with the full 16 seconds of storage capacity.
Further details can be obtained from Bel Marketing, (Contact Details).
Frequency Response | 20-16kHz in x1 mode 20-8kHz in x2 mode |
Distortion | 0.2% max (0dB @ 1kHz) |
Dynamic Range | 90dB typical |
Delay Capacity | x1 = 2 seconds x2 = 4 seconds |
Expandable via optional memory cards to: | |
8 @ 16kHz 16 @ 8kHz | |
Delay Select | Via up/down keypad counter (fast and slow) and LED display |
Modulation | (1) Oscillator (linear up/down ramp) Depth 5:1 (x2 mode) Speed 0.05-6Hz |
Input Impedance | 47Kohms balance bridging |
Output Impedance | 600ohms drive capability |
Power Requirement | 240v 50/60Hz (120v internally adjustable) |
Size | 19" rack-mounting 3½" high x 12" deep |
Review by Paul White
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