Yamaha R1000 Digital Reverb
Reverberation is an important part of our everyday existence. Although we are not normally aware of the processes involved, it provides us with a great deal of information concerning our surroundings. If you've ever tried holding a conversation in an anechoic chamber - ie. a room in which there is practically total absorption of sound and hence no reverberant field - you will know how uncomfortably strange it feels.
It is fairly common knowledge that some materials or surfaces are more absorbent than others. The bathroom is a common acoustic reverb/echo chamber in which the budding songster will often let loose his talent, knowing that somehow things always sound better there.
The enhancing effect of judiciously applied reverb on a live or recorded sound is undoubtedly very significant, and an artificial means of generating it will normally be found somewhere towards the top of a home recordist's shopping list.
Up until now however, the choice of reverb device facing the average private individual has been rather limited. In the past professional studios had always used 'plate' units, wherein a large enclosed metal plate is excited, via an electro-acoustic transducer (a speaker-like affair), by the audio signal, thus providing a high quality, natural-sounding reverberant field to be sent back to the desk for routing.
Such high quality devices are very bulky, sensitive to physical shock and cost several thousand pounds: not the sort of thing that either the bank balance or the front room would take to kindly.
The only viable alternative for inclusion in a limited budget was the reverb 'spring'. Another mechanical device working on a similar principle to the plate but using a series of elastically suspended springs as opposed to a metal plate. The cost of a spring unit can vary from a little over £100 to several thousands, and the quality of the effect is commensurately varying, although generally inferior to that of the plate.
In the natural condition, reverberation is the result of sound leaving its source, travelling outwards at a speed of approximately 1,000ft per second, hitting the various barriers around it (walls, floors, etc.) and bouncing back in all directions. The sound goes on bouncing around, losing a little energy on each bounce, until it is completely spent.
The mechanical reverb unit simply provides an artificial equivalent of this multiple sound path situation, and although it won't sound like a normal room, it's very pleasing.
Such an effect can be simulated by the application of delay line techniques. If there is a reflective wall 40ft away from the sound source, it will take the sound approximately 80ms to get there and bounce back to the source position. This same calculation can be carried out for all the physical objects surrounding the source, and a result will be obtained in the form of a complex pattern of time delays. Therefore, armed with this information, a multi-tap delay line can be used for reverb synthesis.
If you require anything like natural sounding reverb for general use, analogue devices can more or less be crossed off the list because they simply add too much noise and distortion before being able to effect the necessary processing to achieve a natural sound. A microprocessor is also necessary to control the various algorithms (programs) involved, and this is a function of a digital circuit.
It will come as no surprise, then, to find that the answer lies with that technical panacea, 'digital'. A digital device can provide practically unlimited signal processing facilities with very little unwanted noise.
Almost every major studio in the country will now have a digital reverberation system, on its own or in addition to their original plate facility. There is very little argument against the suggestion that digital, in this regard, is the future, and the fact that premier plate manufacturers EMT have ceased production of their range of plates to concentrate on their digital models says a great deal.
Cost is the big drawback with these wonderful new units: they cost thousands of pounds. Or at least they did do before Yamaha brought out their R1000, which retails at an extraordinary £493.00 inc. VAT.
It's a 1U high, 19in rack-mounting unit, and has been designed to be equally useful on stage and in the studio. Unlike its more expensive counterparts, the R1000 is mono in operation with a single input and output on standard ¼in jacks. There is a single rear panel sensitivity switch for both input and output, allowing the machine to operate at a nominal line level of either +4dB, which is the professional studio standard, or -20dB, which actually allows the direct connection of instrument outputs including electric guitars, so that it can be used simply as a pedal. The brochure suggests that guitars should be connected via a suitable preamp, but I tried direct connection and it worked very well. I can't guarantee optimum signal-to-noise ratios or power transfer, but according to my ears, everything was doing fine. In addition to this sensitivity switch there is a front panel input level control with an adjacent, 2-colour, 4-segment LED bargraph to allow optimum level setting.
A 'dry/mix' control adjusts the balance between the original signal and the reverberation available at the output. If you're using a mixing console with an effects send/return facility, it would be normal to leave this control turned fully to the 'reverb' extreme, but if you are using it straight in-line with an instrument, it would be invaluable in setting the desired balance for each specific musical requirement.
To complete a very comprehensive range of gain structure adjustment, an output control allows accurate matching with the next stage of your system, and in practical situations, where you can't guarantee what you'll be using it with, this degree of control is a great asset.
Again, equally useful for both stage and home recording situations where you may need to change sounds 'live' on the same track, a ¼in jack socket on the front panel provides an input for a foot-operated bypass switch. Alternatively there is a push button adjacent to it.
One of the limitations of the vast majority of spring units is that they only have a single, fixed reverb decay time. In terms of digital devices the R1000 is also limited in that it only has four presets in this regard. The choice of times is also a bit of a mystery: 1.5 seconds, 1.6s, 2.3s and 2.4s. On the actual unit the buttons are simply marked modes 1, 2, 3 and 4, and in fact, practically speaking, somewhere around 1½ seconds plus somewhere around 2½ seconds will cover most normal requirements. There did seem to be a subjective quality difference between modes 1 & 2 and 3 & 4, with the longer settings being smoother and more even in each case. However, I honestly couldn't find anyone who could tell which had the longer decay. Well, even if only two of the four buttons are worth pushing, at least they all look nice, and above each one is a small numbered window (1-4) which is illuminated when the relevant preset is selected.
In addition to the input and output jack sockets on the rear panel there is another pair for the insertion of auxiliary signal processing equipment at the input stage of the unit. Classic applications for this would be the use of a delay line to synthesise the effect of a larger space, or alternatively, an equaliser of some kind to modify the characteristics of the reverberated sound.
Comprehensive tone control facilities are provided at the output of the system in the form of a built-in, 3-band sweepable equaliser using three sets of dual concentric controls, with a front panel bypass switch. The bands covered are 50 to 700Hz, 350 to 5kHz and 2kHz to 20kHz, with +/-15dB gain in each case. This is a fairly standard configuration, but quite sophisticated as an addition to a relatively low cost device. It works well, and is invaluable in achieving a wider range of effects.
'Digital' tends to be the magic word within the industry at the present time, and indeed the technology has solved a lot of problems. However, the R1000 can't be compared with the other processors costing ten or twenty times its price, simply by virtue of the fact that it's digital.
In comparison with such devices it is very limited in what it can do, ie. simple, straight forward reverb with a limited range of decay times. The quality of the effect is also a little inferior, with a higher level of noise, and a less constant decay characteristic resulting from fewer bits of information. But, and this is a 'Big But'; for the price, the R1000 is excellent, and will serve you faithfully for ail the standard, natural reverb requirements, and with the insert facility, who knows what weird combinations you might find satisfaction with.
If you have around £500 to spend on a reverb unit, you probably couldn't do better than the R1000. I think Yamaha might have done it again!
Further information from Yamaha, (Contact Details).
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