SWEET HARMONY

Digitech MV5 Vocal Harmony Processor

Published in SOS July 1996
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Reviews : Effects

Offering 5-part harmony at a budget price, the MV5 is Digitech's easiest to use pitch-shifter yet. The DAVID MELLOR Singers provide the tune...

Compared to many effects units, the Digitech MV5 MIDI Vocalist is extraordinary on two counts: it has no LCD display and it features large, illuminated, user-friendly buttons. These features alone tell me that the MV5 is going to be friendly to use, not fiddly, that I am likely to get quick results from it, and that I shall be able to exploit its full potential.

Perhaps it's a phase I'm going through since I threw out my studio computer (shock! horror!) and started listening to the music I was trying to create, but I really do feel the time has come for manufacturers to concentrate on giving us the features we need in a particular unit, rather than simply making the feature list as long as possible, with the result that many devices are so complex that 95% of their features never get used. The MV5 is a step in the right direction -- it does what it does cleanly and simply. You will need the manual to get started, because this device performs tricks other effects units cannot, but with only 10 minutes experience under your belt you can let your creativity take over and have fun!

The Digitech MIDI Vocalist is an intelligent pitch-shifter. This means that it 'understands' the rules of harmony and can add harmonies to a lead vocal that are appropriate to the key of the song. (Brian May soundalikes may substitute 'guitar' for 'vocal' in the previous sentence, because the unit is not restricted to vocal processing.) Being intelligent and bestowed with a certain amount of good taste, this is not a unit for creating weird, delayed feedback pitch-shift effects, although you can certainly construct such sounds with the aid of a delay unit and a little bit of mixing console know-how.

Up to four harmonies are allowed in four distinct and useful modes of operation. Taking a look at the front panel first, the most obvious feature is the group of six buttons set into a musical staff with a treble clef. If you were thinking that the positions of the buttons on the staff meant something, then you had been fooled too. It's simply a design feature, but the fact that they slope at an angle does represent the relative pitches of the harmonies, if not the actual notes. These six buttons allow the user to select four harmonies spaced above or below, or in unison, with the input note. It's a quick and easy way to create the harmony voicing you are looking for and the MV5 will select the actual pitches for you.

Bypassing for the moment a group of six buttons which select the mode of operation and the key of the song -- more on these later -- we come to three rotary controls which set the input level, the output level of the lead vocal (the source signal) and the level of the harmonies. It couldn't be simpler. A front panel XLR is provided (sadly, without phantom power) for a microphone input.

For those of you who are as interested in the back of equipment as in the front panel, the principal features are a line input, stereo outputs, and the normal trio of MIDI sockets. Another socket is provided for the Digitech FS300 footswitch, which can be used to control the Set Key, Harmony Mode, and Bypass functions. A single momentary action footswitch may be used to control the Bypass function. Also on the back is the input for the 'wall-wart' power supply. I'll continue to complain about these devices as long as manufacturers use them because, as well as being inconvenient, I know that the easiest way to destroy equipment is to get your warts mixed up. This is easily done, since they seem to come in an endless variety of different voltages and polarities. There is a fortune awaiting the inventor who can design a powering system that is as convenient for the manufacturer (allowing them to sell identical units worldwide) as a wall-wart and works for the user, too.

Having dealt with the hardware, let's look individually at the MV5's four modes of operation.

Chordal Harmonies
To produce chordal harmonies, the MV5 needs two inputs. One is your voice (or lead instrument) and the other is MIDI information from your keyboard. In this instance the keyboard isn't used to generate sounds, just to tell the MV5 which harmonies to create. In a studio situation you would probably record the lead vocal onto tape and spend as much time perfecting it as you need, whilst the MV5 quietly bides its time in the rack. Then you could record basic chords into your synchronised sequencer, which you would then play back via MIDI into the MV5. The MV5 will analyse the chords you play, and automatically select suitable harmonies based on these chords and the settings of the Harmony Voicing buttons on the front panel. As you record the harmonies to tape you will probably drop in and out of record mode, so that harmonies only go where you want them, since the MV5 in this mode will always create harmonies according to the last MIDI data it received.

As well as being useful in the studio, the MIDI Vocalist could be exploited in a live situation by a singer/keyboard player performing solo in a bar, for instance. In this situation, the keyboard is being used for accompaniment, as well as transmitting MIDI data to the MV5 telling it about the chords being played. Here we have potential for confusion, since any fancy arpeggios, grace notes or glissandi could fool the MV5 into creating the wrong harmonies.

Obviously a little bit of extra care is necessary in playing, along with tasteful use of the Bypass footswitch. To help matters though, the MV5 can be instructed to respond over a set range of MIDI notes only and ignore all others. This is easy to achieve, and it would only take a moment to reset the zone between songs.

If you are wondering whether the MV5 has a full understanding of harmony, or whether it can only handle Status Quo songs, then take a look at the list of chord types (see box). The great thing is that even if you don't know a flattened fifth from a sharpened Chinagraph, the MV5 does and the harmonies will always fit in with the chords you are playing.

Scalic Harmony
While Chordal mode will nearly always work for most types of music, it tends to produce harmonies that are a bit static. In fact, they are only as static as the MIDI notes you send to the MV5, but one's fingers always seem tempted to the same intervals as long as they seem to be working. Scalic mode, on the other hand, doesn't always work for every style of music, but it will produce much more activity in the harmony lines. If you think of Chordal mode as a choir backing a solo voice, and Scalic mode as a more interactive style of harmony, then you won't go far wrong. Alternatively you can think of Chordal as 'Amazing Grace' mode, and Scalic as 'Eagles' mode. (It's OK -- they're trendy again!).

In Scalic mode, you don't need to play chords all the way through a song. A single chord, containing the important notes of the scale, played at the beginning will be enough to tell the MV5 which key you are in and which scale type you require. If you change key or scale type during the song, then you will need to input another chord or the harmonies will be out of key. Notice that once you have specified a key, the MV5 handles all the chord changes that are customary in that key for the type of scale selected. (See box for a list of scale types.) Apart from the common-as-muck Major and Minor varieties, highlights of the scale type list are the Dorian scale, which adds the minor third and flattened seventh that are appropriate for blues style harmonies, and also the Whole Tone scale, which creates instant musical impressionism à la Debussy.

In Scalic mode, the Harmony Voicing buttons also define the spacing of the harmonies. I didn't mention it earlier, but normally the MV5 corrects the pitch of the harmonies. So if your singing is out of tune, at least the backing vocals will be OK (provided you sing within a quarter tone of the correct pitch). Sometimes, however, too much perfection can get a bit boring and you might wish for a little sliding (portamento) of the notes to give a more relaxed feel. If so, then all you have to do is send an upward MIDI pitch-bend command to the MV5 and it switches into a mode where the harmonies track the vocal precisely.

Vocoder Mode
Now don't go thinking that there is a full-blown vocoder built into the Digitech MV5 as well as a harmony processor. 'Vocoder' is about as descriptive in this respect as the word 'coffee' on a vending machine -- it indicates the flavour of what you are about to receive without actually promising the real thing!

In Vocoder mode, all the intelligence of the MV5 is bypassed (as are the Harmony Voicing buttons) and harmonies are created which exactly correspond to the notes you play on your MIDI keyboard. Vocoder mode is actually more versatile than the other modes because you can create exactly the harmonies you want, whether or not they fit into 'proper' chords or scales. You could even take an out-of-tune vocal recording and feed it through the MV5 while playing the correct notes on the keyboard, and magically a perfectly in-tune vocal would result. In fact, the original vocal doesn't even have to be close to the right notes, because the MV5 will harmonise a dog's bark if necessary. Of course, there are limits to how well this process can work. Basically, the more work the MV5 has to do, and the more the vocal slides about, the less believable the end result becomes. Overall, I'd say this vocoder technique is best applied to backing vocals, where a little bit of 'flanginess' might go unnoticed in the mix.

Detune Mode
This is another mode where the intelligence of the Digitech MV5 is put on hold, yet it could easily become the mode in which the unit is most used. One of the most common requirements in recording is for some sort of 'thickening up' of the sound, especially on vocals. If you have ever sat in front of the mixing console wondering what you could do to turn that thin, weak vocal wafting out of your monitors into a fine, healthy specimen, bursting with life and vigour from the drive units, then this mode could represent one potential solution to your problem. You can achieve a similar effect with many other effects devices, but on the MV5 it's achieved with the push of a couple of buttons -- and as we all know, the sounds which are easy to get at are the ones that are going to be used.

There are three possibilities: Light Detune adds harmonies at plus and minus seven cents to the original (one cent is one hundredth of a semitone), Heavy Detune adds harmonies at plus and minus 12 cents, and for the strongest effect you can combine the two. If you have used this trick before, you will understand its benefits and limitations, but I think that Digitech have provided three options which will cover most eventualities and can be accessed very easily.

Digitech have an immense amount of experience in designing pitch-shifters, so you would be entitled to expect pretty good sound quality from the MV5. If you bear in mind that real-time pitch-shifting is the most difficult effect to achieve, and that perfection will probably remain unattainable for many years yet, then I think most users will be very satisfied with the sound of the MV5. Even though the 31.25kHz sampling rate only results in an audio bandwidth of 11.5kHz, when used for backing vocals nobody is going to point at you and accuse you of cheating with a fancy effects unit. They'll believe you sang all the harmonies for real. I couldn't say that the pitch-shifted output sounds absolutely as clean as the original signal, but I couldn't say that about any pitch-shifter -- even the most expensive models.

In conclusion, I'll repeat myself and say that I think you will be very satisfied with the Digitech MV5. It does a good, solid job of work and you don't need a brain expansion to use it.

Although the Digitech MIDI Vocalist is admirably easy to use, those who like to push their equipment to its limits will find that that there are extra functions accessible only via MIDI. You may have noticed that the MV5 doesn't offer factory or user preset programs. It doesn't need to, since you can set the unit from scratch almost as quickly as you could recall a preset. You might think that this means you can't automate the MV5 as you can with other effects units, but you would be wrong. Each time you press a button on the MV5, a MIDI message is output which you can record into a sequencer. This could include Harmony Mode, Voicing, Key/Scale, Chord Root/Type and Setup changes. When you replay the sequence, the MV5 will respond as though you were pressing the buttons yourself. This includes the Bypass control, which receives more use than the bypass function on any other type of effects unit, since the MV5 creates harmonies in response to the input signal all the time, and you almost certainly wouldn't want those harmonies to appear all the way through the song. You can also send a MIDI Control Change message to set the vibrato depth, which cannot be set from the front panel. Extra voicings are available via MIDI messages, just in case you can't find what you are looking for from the six front panel Harmony Voicing buttons.

• Microphone Input: Balanced XLR, >2kohms

• Line Input: Unbalanced jack, >10kohms

• Input Level (mic): -31dBu to -3dBu

• Outputs: Two unbalanced jacks, 1.5kohm

• Maximum output level: +14dBu +/-2dB

• Sampling: 16-bit linear at 31.25kHz

• Frequency Response: 30Hz to 11.5kHz, +0.5/-3.0dB through DSP30Hz to 30kHz, +/-1.5dB, analogue bypass

• Signal-to-Noise Ratio: >86dB A-weighted through DSP>92dB A-weighted, analogue bypass

• THD: <0.03% at 1kHz

In Chordal Mode, the Digitech MIDI Vocalist will recognise any of the following chord types, in any key:
• Major
• Major 7
• Minor
• Minor 7
• Dominant 7
• Major 6
• Augmented 7
• Minor 7 flat 5
• Diminished
• Suspended
• Suspended 7
• Minor-major 7.

In Scalic Mode, the Digitech MIDI Vocalist can be set to any of the following scale types, in any key:
• Major
• Major raised 7
• Major lowered 5
• Major 6
• Dorian
• Minor
• Harmonic Minor
• Diminished
• Whole Tone

pros
• Simple-to-use and effective.
• No LCD display (you don't need one!).
• No nudge buttons (you don't need them).
• Good quality pitch-shift.

cons
• 'Wall-wart' external power supply.
• No phantom power for microphone.

summary
Probably the simplest intelligent pitch-shifter available, and one of the most effective. Doesn't offer every function of the more expensive Digitech Studio Vocalist, but it is a lot easier to use to the full.

info

£ £449.95 inc VAT.

A Arbiter Music Technology, Wilberforce Road, London NW9 6AX.

T 0181 202 1199.

F 0181 202 7076.