Tr oubleshooting continued, Tr oubleshooting technical specification, Using the insert point – Joemeek MC2 Stereo Compressor User Manual

Page 7: Tr oubleshooting

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13

Tr

oubleshooting

continued...

6) T

oo much noise

• Is the ‘Input Gain’

control too high (eg: the input signal is too small)?

• Is the noise already present in the input signal? (T

ry removing the input).

Is

the

‘Make

Up

Gain’

control

too

high

(eg:

when

lots

of

compression

is

being used)?

Tr

y

us

in

g

th

e

G

R

H

ol

d

fu

nc

tio

n

to

c

om

pe

ns

at

e

fo

r

co

m

pr

es

so

r

ac

ce

nt

ua

te

d

no

is

e.

7) Sounds distorted

• Is the ‘Input Gain’

control too high?

• When using the compressor

, is the Release control set too low?

Is

the

GR

Hold

on

with

the

control

set

too

low?

Tr

oubleshooting

Technical Specification

Input impedance

Line: 20kohm

Pre-amp overall gain

-6dB to +15dB

Common mode rejection

70dB

Equivalent input noise

-95dBu (unweighted)

Distortion

0.001% (below Compressor

threshold)

Frequency response

10Hz to 70kHz (-3dB)

Maximum input before clipping

+19.5dBu

Headroom before clipping

+19.5dBu

Compression threshold

-6dBu to +22dBu (variable)

Compression ratio

1:1 to 10:1 (variable)

Compressor attack time

1 msec to 100 msec

(adpative)

Compressor release time

0.1 sec to 3 sec (adaptive)

GR Hold rhreshold

-10dBu to -50dBu (variable)

Stereo Width range

Mono / stereo / wide stereo

(variable)

GR Meter

8 segment bargraph

VU Meter

8 segment bargraph

Nominal output levels

+4dBu/-10dBv

Output impedance

75ohm

Output Level switch

12dB attenuation

Noise Floor

-95dBu (typical, with 0dB

Input and Make Up gain)

Power supply

12V ac mains adaptor

Power consumption

12W

Mechanical

220W x 44H x 180D (overall)

W

eight

1 kilo

12

Using

the

Insert

Point

This

unbalanced

“Send

and

Return”

jack

allows

you

to

patch

other

pieces

of

equipment,

such

as

a

graphic

equalizer

into

the

compressor

’s

control

circuitry

, for “frequency conscious” compression.

If

you

boost

certain

frequencies

with

an

external

equalizer

,

those

frequen

-

cies

are

going

to

cause

the

compressor

to

respond

more,

ie:

squash

the

program

material

more.

If

you

cut

certain

frequencies,

the

compressor

will

respond

less

to

those

frequencies.

Uses

for

this

can

be

either

creative

or

corrective.

Imagine

you

are

trying

to

even

out

the

vocals

in

a

mix,

but

the

mix

is

bassheavy with the result that

each bass note squashes the vocals.

A

mod

-

est

amount

of

bass-cut

on

the

external

equalizer

will

make

the

compressor

respond less to the bass, allowing it to do its job of controlling the vocals.

On

the

other

hand,

you

might

want

to

have

a

vocal

or

a

drum

beat

deliber

-

ately

“duck”

the

rest

of

the

mix

for

special

ef

fect.

T

une

the

external

equaliz

er

to

the

frequencies

of

the

instrument

you

want

to

emphasize,

then

adjust

the

‘COMPRESS’

control

so

that

the

compressor

only

operates

when

those

frequencies are present.

Note that none of this external equalization is audible as such.

Tr

oubleshooting

1) No Power (no lights work)

• Is the power supply plugged in (both ends)?

• Is the mains power on?

• Has a mains fuse blown?

2) The Inputs don’t work

• Is the source connected to the jack inputs on the back of the unit?

• Is the ‘Input Gain’

control turned up?

3) The compressor doesn’t work

• Is the ‘Comp’

switch in (LED on)?

• Is the ‘Compress’

control turned up enough?

• Is there enough signal, as set by the ‘Input Gain’

control, to drive the

compressor?

• Is the ‘Slope’

control turned up enough?

4) T

oo little or too much compression

T

urn the ‘Input Gain’

control up or down respectively

, to adjust the

signal level to the compressor

.

T

urn the ‘Slope control up or down respectively

.

5)

The Stereo Width doesn’t work

• Is the ‘ON’

switch in (LED on)?

• Is only one input connected?

• Is the programme material mono?

mc2 manual.indd 14-15

3/20/06 12:51:42 PM

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