Manley Langevin Dual Vocal Combo 1999 - 4/2001 LDVC000 - LDVC178 User Manual

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J) DIRECT INPUT. This is for plugging in an electric guitar, bass, synth, etc into the Dual Vocal Combo. The

input impedance is high (150 kOhms) appropriate for these instruments and there should be plenty of gain

available. Electric guitars and basses may need a fair amount of H.F. Boost to sound comparable to an amp

because there happens to be a lot of H.F. boost going on in the innards of most amps. A jack plugged into

this input will interrupt the normal mic XLR input.

OPTO-LIMITER SECTIONS

K) IN / BYPASS. BYPASS turns off the limiter and its controls. IN allows limiting or levelling. This should be

the most used control on the limiter. Always compare the original sound to the sound after the limiter to verify

you are not accidentally over-squashing. Remember that sound is compised of pitch, duration and volume or

dynamics. The point is not to throw away one element (dynamics) just tame it and control it as needed.

L) GAIN. This is the ‘Make-up Gain’ after the limiter. It is usually set so that there is no volume change when

switching IN / BYPASS to allow easy A/B comparisons OR as the final output level to optimise how hard the

signal is hitting tape or to optimise the level to an A to D convertor.

M) REDUCTION. This sets the THRESHOLD of limiting and the amount of limiting. Turning it clockwise,

creates deeper limiting. We generally advise that 4 to 6 dB of limiting (levelling) is fine for vocals and most

individual intruments and 1 to 3 dB is good for percussive sounds and mixes. Too much limiting on a mix will

usually first make the drums quieter which is not generally desirable. The amount one should ‘level’ vocals

depends mostly on the singer’s technique and talent, the musical style and the thickness of the arrangement.

Sometimes with very dynamic vocals, loud dense tracks and a mix that is not vocal forward significantly more

levelling might be needed. We have heard of people using 10 to 12 dB of vocal limiting with good results but

a bunch more extra care will be needed. In the pauses between lines, the gain will rise that 10 or 12 dB along

with headphone leakage, air conditioning rumble, throat noises, etc. Don’t forget that if you are like many

engineers, you will be limiting the vocal again in the mix, so don’t feel you have to do all the limiting during the

recording - play it safe. There is no Un-Do button, and the alternative is the dreaded Re-Do. Questionble EQ,

you can fix, over limiting is very difficult to fix later.

N) METER OUTPUT / REDUCTION. This switch is for the VU meters. In METER OUTPUT, the VU’s show

the final output level like most VU meters. In REDUCTION mode the meters show how much limiting is

occurring in dBs. Because VU meters are not lightning-fast, you may not see all the limiting that is actually

happening with fast transient sounds.

O) VU METERS. These are smaller versions of standard Sifam VU meters. It is worth pointing out that VU

meters were always intended to correspond to apparent ‘volume’ similar to how our ears work and are not like

the ‘peak’ meters you have on your digital recorders. VU meters work great for analog tape, but for digital use

the ‘LED ladders’ on your A to D or digital machine. The meters should glow when power is on.

P) SEP / LINK. This switch allows the 2 limiters to act independently (SEPARATE) or to ‘track’ together in

LINK mode. SEP is used if each channel has different types of sounds going through it. LINK is used for ste-

reo sounds. When limiters or compressors are linked and a loud signal on one side forces limiting then, both

limiters pull down the same amount of dBs. This is so that the center image doesn’t tug one direction then the

other, which is a bit distracting and wrong sounding. With this unit, set up BOTH channels for normal limiting

then switch to LINK. Some limiter compressors just use the just left channel controls in LINK mode and while

convenient is not really the right way. Those limiters “mono” the audio that controls the limiting which gives

excess limiting for sounds in the center and no limiting for out-of phase sounds, meanwhile peaks in either

channel can overload the A to D. The Langevin and Manley units combine the control voltages rather than the

audio and provide a more useful limiting function but not quite as conveniently.