AKG PERCEPTION 820 User manual

USER INSTRUCTIONS . . . . . . . .p. 2
Please read the manual before using the equipment!
MODE D’EMPLOI . . . . . . . . . . . . . . . .p. 20
Veuillez lire cette notice avant d’utiliser le système!
PERCEPTION 820 TUBE
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 1 (Schwarz/Black Auszug)

2PERCEPTION 820 TUBE
Table of Contents
Page
1 Safety and Environment...............................................................................................................3
1.1 Symbols Used .......................................................................................................................3
1.2 Safety Instructions .................................................................................................................3
1.3 Environment..........................................................................................................................3
2 Description ..................................................................................................................................4
2.1 Introduction...........................................................................................................................4
2.2 Packing List ..........................................................................................................................4
2.3 Optional Accessories..............................................................................................................4
2.4 Microphone...........................................................................................................................4
2.5 Remote Control Unit ...............................................................................................................4
2.5.1 Front Panel...................................................................................................................5
2.5.2 Rear Panel ...................................................................................................................5
3 Setting Up....................................................................................................................................7
3.1 Important Note ......................................................................................................................7
3.2 Connecting the Microphone....................................................................................................7
3.3 Connecting the Remote Control Unit to Power...........................................................................7
3.4 Powering Up..........................................................................................................................7
3.5 Powering Down .....................................................................................................................8
4 Using the Microphone..................................................................................................................9
4.1 Introduction...........................................................................................................................9
4.2 Bass Cut Filter .......................................................................................................................9
4.3 Preattenuation Pad ..............................................................................................................10
4.4 Hints on Microphone Placement............................................................................................10
4.4.1 Lead Vocals................................................................................................................10
4.4.2 Choir/Backing Vocals...................................................................................................10
4.4.3 Trumpet, Trombone .....................................................................................................11
4.4.4 Electric Guitar/Bass.....................................................................................................12
4.4.5 Violin, Viola .................................................................................................................12
4.4.6 Double Bass, Cello ......................................................................................................13
4.4.7 Acoustic Guitar ...........................................................................................................13
4.4.8 Flute ..........................................................................................................................13
4.4.9 Clarinet......................................................................................................................14
4.4.10 Tenor and Soprano Saxophones .................................................................................14
4.4.11 Grand and Upright Pianos ..........................................................................................14
4.4.12 Drums .....................................................................................................................15
5 Cleaning ....................................................................................................................................16
6 Troubleshooting.........................................................................................................................16
6.1 Replacing the Fuse ...............................................................................................................16
6.2 Solving Problems..................................................................................................................17
7 Specifications............................................................................................................................18
7.1 Microphone.........................................................................................................................18
7.2 Remote Control Unit .............................................................................................................18
Frequency Response and Polar Patterns.......................................................................................19
Conformity....................................................................................................................................38
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 2 (Schwarz/Black Auszug)

3PERCEPTION 820 TUBE
1.1 Symbols Used
1.2 Safety Instructions
1.3 Environment
The lightning flash with arrowpoint in an equilateral triangle means that there are
dangerous voltages present within the unit.
The exclamation point in an equilateral triangle on the equipment indicates that it
is necessary for the user to refer to the User Manual. In the User Manual, this
symbol marks instructions that the user must follow to ensure safe operation of
the equipment.
1. Do not spill any liquids on the equipment and do not drop any objects through the ven-
tilation slots in the equipment.
2. Use the equipment in dry rooms only. Do not expose the equipment to rain or splash
water. Never place objects containing liquids (e.g., vases) on or near the equipment.
3. There are no user-serviceable parts inside the equipment. Do not attempt to service the
equipment yourself. Refer all servicing to qualified personnel. Opening the chassis for any
reason will void the manufacturer’s warranty.
4. Before connecting the equipment to power, check that the AC mains voltage stated on
the power supply included with the equipment is identical to the AC mains voltage avail-
able where you will use the equipment. Also check that the power outlet is a standard
type with a protective ground connection. Disconnecting the protective ground lead or
using non-standard power plugs or non-standard power outlets is illegal.
5. Operate the equipment with the power supply included with the equipment only. Using
a different power supply may cause serious damage to the unit.
6. If any solid object or liquid penetrates into the equipment, shut down the sound system
immediately. Disconnect the equipment from power immediately and have the equipment
checked by AKG service personnel.
7. If you will not use the equipment for a long period of time, disconnect the equipment from
power. Please note that the equipment will not be fully isolated from power when you set
the power switch to OFF.
8. Disconnect the equipment from power during storms to prevent damage.
9. Make sure to route power supply cords so that they are not likely to be walked on or
pinched by items placed upon or against them, paying particular attention to cords at
plugs, convenience receptacles, and the point where they exit from the equipment.
10. To avoid hum or interference, route all audio lines, particularly those connected to mi-
crophone inputs, away from power lines of any type. If you use cable ducts, be sure to
use separate ducts for the audio lines.
11. Make sure to replace the built-in fuse with a standard fuse of the same type and rating
only. Using any other type of fuse may cause excessive heating and/or a risk of fire.
12. Do not place the equipment near heat sources such as radiators, heating ducts, or am-
plifiers, etc. and do not expose it to direct sunlight, excessive dust, moisture, rain, me-
chanical vibrations, or shock.
13. Clean the equipment with a moistened (not wet) cloth only. Be sure to disconnect the
equipment from power before cleaning the equipment! Never use caustic or scouring
cleaners or cleaning agents containing alcohol or solvents since these may damage the
enamel and plastic parts.
14. Use the equipment for the applications described in this manual only. AKG cannot ac-
cept any liability for damage resulting from improper handling or misuse.
1. When scrapping the equipment, separate the case, circuit boards, and cables, and dis-
pose of all components in accordance with local waste disposal rules.
2. The packaging of the equipment is recyclable. Dispose of the packaging in an appropriate
container provided by the local waste collection/recycling entity and observe all local
legislation relating to waste disposal and recycling.
1 Safety and Environment L
!
L
↯
L
!
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 3 (Schwarz/Black Auszug)

4PERCEPTION 820 TUBE
2 Description
2.1 Introduction
2.2 Packing List
2.3 Optional Accessories
2.4 Microphone
2.5 Remote Control Unit
Thank you for purchasing an AKG product. This Manual contains important instructions for
setting up and operating your equipment. Please take a few minutes to read the instruc-
tions below carefully before operating the equipment. Please keep the Manual for fu-
ture reference. Have fun and impress your audience!
•PERCEPTION 820 TUBE microphone
• Remote Control Unit
• Audio/control cable
• Spider-type shock mount
• US type power cord
• UK type power cord
• European type power cord
• Check that the packaging contains all of the items listed above. Should any of these
items be missing, please contact your AKG dealer.
• For optional accessories, refer to the current AKG catalog or folder, or visit www.akg.com.
Your dealer will be glad to help.
The PERCEPTION 820 TUBE is a high quality, true condenser microphone with a 1-inch dual
large-diaphragm transducer.
What sets it apart from other condenser microphones is that it uses a vacuum-tube pream-
plifier. Unlike conventional solid-state electronics, a tube preamplifier adds even-order har-
monics to the signal. Although these are low in level, they create a rich, warm,
three-dimensional sound. This characteristic in conjunction with the typical response of the
large-diaphragm transducer will give your recordings a degree of warmth and “musicality”
that is difficult to achieve with solid-state microphones.
The microphone incorporates a carefully selected ECC 83 tube. If the tube needs replacing,
you may alternatively use a 12AX7 tube. This type is similar to the ECC 83.
Other features of the PERCEPTION 820 TUBE include:
•Selectable polar patterns: The microphone’s transducer uses a dual diaphragm. This
sophisticated technology allows you to select the optimum polar pattern (cardioid, om-
nidirectional, figure eight, and six intermediate patterns) for every application.
•Gold-sputtered diaphragm: The diaphragm is made of a plastic foil that is gold-sput-
tered on one side only to prevent shorting to the back electrode even at extremely high
sound pressure levels.
•All-metal body: The all-metal body adds to the rejection of RF interference so you can
use the microphone near transmitter stations and along with wireless microphones or
other communications equipment. The extremely rugged, heavy body and sturdy front
grill protect the microphone from damage from tough handling on stage.
•High headroom: Capable of handling sound pressure levels up to 155 dB and built to
resist high temperatures and humidity, the microphone will give excellent results in a wide
range of applications.
The Remote Control Unit delivered with your microphone
• provides the filament and plate voltages for the vacuum tube,
• supplies the polarization voltage for the transducer,
• lets you select one of nine different polar patterns,
• provides a 20-dB preattenuation pad, and
• allows you to switch in a bass cut filter.
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 4 (Schwarz/Black Auszug)

5PERCEPTION 820 TUBE
2 Description
2.5.1 Front Panel
Fig. 1: Controls on the
Remote Control Unit
front panel.
Refer to fig. 1.
2.5.2 Rear Panel
Fig. 2: Controls, inputs, and
outputs on the Remote
Control Unit rear panel.
Refer to fig. 2.
Important!
Important!
A POWER LED: This blue LED is lit to indicate that power to the Remote Control Unit is ON.
B Polar pattern selector: This rotary switch lets you select the microphone’s polar pat-
tern from omnidirectional (fully CCW) to cardioid (center) to figure eight (fully CW). Be-
tween these settings, there are six intermediate patterns. All switch positions are
detented, so all settings are easily and unambiguously reproducible.
C Preattenuation switch: This toggle switch lets you increase the microphone’s headroom
by 20 dB for close-in recording with extremely low distortion. The preattenuation pad pre-
vents the microphone's output level, particularly at low frequencies, from overloading the
miniature transformers used in many mixer input stages, etc.
D Bass cut switch: This toggle switch lets you reduce low-end distortion caused by foot-
fall or wind noise, etc. The bass cut filter also minimizes the proximity effect that close-
in miking from less than 4 inches causes in any unidirectional microphone. The filter
rolls off at 12 dB/octave from 80 Hz downward.
E POWER switch: Turns power to the unit ON (position “I”) and OFF (position “0”). The front
panel POWER LED is lit while power is ON and goes out when you turn power to the unit
OFF.
F AC input: Standard IEC power receptacle with integrated fuse holder.
• To avoid damage, use replacement fuses of the same type and rating (125 mA/
250 V, slow-blow) only.
G Power voltage selector: Sets the input power voltage to 210 - 240 VAC (“210-240V”
position) or 110 - 120 VAC (“110-120V” position).
• To avoid damage, always make sure that the power voltage selector is set to the
same voltage as the power voltage available where you are going to use the unit.
H INPUT: 7-pin female XLR connector for connecting the dedicated audio/control cable
for the microphone.
I OUTPUT: This balanced 3-pin XLR connector provides the microphone output signal.
A
BCD
L
!
L
!
H I J
G
F
E
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 5 (Schwarz/Black Auszug)

6PERCEPTION 820 TUBE
2 Description
Refer to fig. 2 on page 5. J GROUND LIFT: This pushbutton switch allows you to remove hum caused by ground
loops.
To open the chassis ground connection, press the GROUND LIFT button OUT (“LIFT” po-
sition).
To restore the chassis ground connection, press the GROUND LIFT button IN (“GROUND”
position).
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 6 (Schwarz/Black Auszug)

7PERCEPTION 820 TUBE
3 Setting Up
3.1 Important Note
3.2 Connecting
the Microphone
Fig. 3: Connecting the micro-
phone to the Remote Control
Unit and mixer.
Refer to fig. 3.
3.3 Connecting
the Remote Control Unit
to Power
Refer to fig. 2 on page 5.
Table 1: Power voltage vs. se-
lector setting and power cord
Important!
3.4 Powering Up
Note:
• To avoid damage or electric shock, mount the microphone on a suitable stand
and make all audio connections before connecting the Remote Control Unit to
power.
1. Use the supplied audio/control cable (A) to connect the microphone output to the INPUT
connector(B) on the Remote Control Unit rear panel.
2. Use a standard balanced XLR cable (C) (optional) to connect the OUTPUT connector (D)
on the Remote Control Unit rear panel to the desired microphone input on your mixer.
1. Prior to connecting the Remote Control Unit to power, check what power voltage is avail-
able where you are going to use the microphone.
2. Set the power voltage selector (G) on the rear panel to the correct position as shown in
Table 1 below.
3. Referring to Table 1 above, use the correct power cord to connect the Remote Control
Unit to a grounded power outlet.
When on tour, you may encounter power outlets that do not match the power plug on
any of the supplied power cords.
• Purchase a suitable power cord locally that complies with IEC and local safety
standards and has a power plug with a chassis ground pin.
• To avoid damage or electric shock, connect the Remote Control Unit to a grounded
power outlet only.
• If in doubt about the power connection, consult a local electrician.
• Set the power switch on the Remote Control Unit rear panel to “I”.
After about ten seconds, the heating voltage will have reached the specified level and
the front panel POWER LED will be lit. About twenty seconds later, the microphone will
be ready to operate.
• You may not get the full splendor of the tube sound before the electrodes have reached
the required operating temperature. Therefore, we recommend powering up at least
L
!
A
BD
Power voltage Selector setting Power cord
210 to 240 VAC, 50/60 Hz 210-240V UK or European type
110 to 120 VAC, 50/60 Hz 110-120V US type
L
!
C
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 7 (Schwarz/Black Auszug)

8PERCEPTION 820 TUBE
3 Setting Up
3.5 Powering Down
five minutes before starting to record. This will allow the tube inside the microphone
to heat up properly,
1. Set the power switch on the Remote Control Unit rear panel to “0”.
The front panel POWER LED will go out.
2. Wait for five minutes to allow the tube to cool down to room temperature before mov-
ing the microphone. A hot tube will be more susceptible to mechanical damage than a
cold one.
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 8 (Schwarz/Black Auszug)

9PERCEPTION 820 TUBE
4 Using the Microphone
4.1 Introduction
Note:
4.2 General Hints
Fig. 4: Microphone front.
Using vacuum-tube electronics and a large-diaphragm transducer, the PERCEPTION 820
TUBE is suited for a wide range of applications. It will add the typical warmth and richness
tube microphones are famous for to female and male voices as well as many instruments.
The following sections contain general hints on using the microphone and suggestions on
how to place the microphone for voices and various instruments.
• Please remember that vacuum tubes with their heater filaments are more delicate than
solid-state components. Even a drop from moderate height may cause the filament to
break and the microphone to fail. So always handle the microphone with extreme care.
• Refer to fig. 4. Whichever polar pattern you select, it may be good to know which way
the transducer axis is facing: the front of the microphone is the side of the body with the
AKG logo on it.
• When recording wind instruments or vocals, make sure not to blow or sing directly into
the microphone.
To get professional sounding results with no unwanted wind and pop noise (exaggerated
“p” and “t” sounds), place an optional PF 80 pop screen from AKG between the micro-
phone and vocalist/instrument.
• Keep the microphone dry. Moisture from blowing or singing directly at the capsule from
a short distance, or extremely high humidity may cause the microphone to start crack-
ling or go very quiet due to partial short circuits in the polarization voltage.
• If you use the microphone in the open, use an optional AKG W 4000 windscreen to pro-
tect the microphone from moisture and reduce wind noise.
• Loud instruments: You can use this microphone for close-in recording of very loud in-
struments (brass instruments, kick drum, etc.). Just switch the preattenuation pad in to
increase the microphone’s capability of handling sound pressure levels to 155 dB.
- To switch the preattenuation pad in, set the preattenuation switch on the Remote
Control Unit front panel to “-20 dB”.
- To switch the preattenuation pad out of circuit, set the preattenuation switch to “0”.
• Low-frequency noise: The supplied spider type shock mount reduces footfall or other me-
chanical noise to a minimum.
The switchable bass cut filter at 80 Hz will effectively suppress any remaining low-fre-
quency noise such as fan noise from air conditioning systems, etc., or floor vibrations,
handling noise, etc. without affecting the sound of the recorded voice or instrument on
tape.
- To switch the filter in, set the bass cut filter switch on the Remote Control Unit front
panel to the “ “ position.
- To switch the filter out of circuit, set the bass cut filter switch on the Remote Con-
trol Unit front panel to the “—“ position.
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 9 (Schwarz/Black Auszug)

10 PERCEPTION 820 TUBE
4 Using the Microphone
4.3 Selecting
Polar Patterns
4.4 Hints on Microphone
Placement
4.4.1 Lead Vocals
Fig. 5: Solo vocalist.
4.4.2 Choir/
Backing Vocals
Fig. 6: Miking a large
mixed choir.
Each of the PERCEPTION 820 TUBE’s selectable polar patterns is virtually frequency inde-
pendent so that reflected sound, too will be reproduced accurately and uncolored.
•Omnidirectional (left-hand setting): This is the preferred setting for “all around the
mic” recording, high quality ambience (audience sound) miking, or far-field recording in
exceptionally good-sounding large or small recording rooms, etc.
•Cardioid (center setting): This is a standard setting for recording and gives excellent
results on all kinds of voices and a wide range of instruments. Remember to aim the mi-
crophone front (see fig. 4 on page 8) at the sound source.
•Figure eight (right-hand setting): The microphone will pick up sounds arriving from the
front and rear with equal sensitivity. Use this mode to mic up the side signal in M/S
stereo recording or to record two sound sources (talkers, instruments) facing each other.
It is also a good choice for cymbal overhead miking.
Every instrument radiates its sound in a specific way. Therefore, to get the best sound, do
not hesitate to experiment with microphone placement.
As an introduction to the “secret science of making good recordings”, the following sections
describe some proven miking techniques. (Illustrations show generic microphones.)
• Place the microphone 6 to 12 in.
(15 to 30 cm) from the vocalist’s
mouth.
• Select the cardioid polar pattern:
set the polar pattern selector to
cardioid ( ).
• Switch the bass cut filter in: set
the bass cut switch to “ ”.
• We strongly recommend placing
a PF 80 pop screen (available as
an optional accessory) between
the microphone and vocalist to
eliminate pop noise.
• To give the vocalist better control
of their own voice, we recom-
mend adding the vocalist's track
to their headphone monitor sig-
nal.
• To record large mixed choirs, we
recommend using a pair of car-
dioid microphones to get a stereo
signal, plus one PERCEPTION 820
TUBE each for the soprano, alto,
tenor, and bass sections.
- Set each PERCEPTION 820
TUBE to cardioid ( ).
- Place each microphone about
5 feet (1.5 m) in front of the re-
spective section, about 6 feet
(1.8 m) above the ground.
- Aim each microphone at the
center of its assigned section.
B T A S
60°60°
P 820 P 820 P 820 P 820
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 10 (Schwarz/Black Auszug)

11PERCEPTION 820 TUBE
4 Using the Microphone
Fig. 7: Using a stereo pair to
record a choir.
Fig. 8: Backing vocalists
sharing a single microphone.
4.4.3 Trumpet, Trombone
Fig. 9: Trumpet (a),
trombone (b).
• In rooms with good acoustics,
a pair of PERCEPTION 820
TUBEs will often do the trick.
- Set each microphone to
cardioid ( ).
- Use an optional H 50 stereo
bar to mount the two mi-
crophones on a stand.
• Place the stereo pair about
10 feet (3 m) in front of the
choir, about 8 feet (2.4 m)
above the ground.
- Aim the stereo pair at the
center of the choir.
- Turn the left-hand micro-
phone 60 degrees to the left and the right-hand microphone 60 degrees to the right.
Backing vocals/technique 1:
Refer to section 4.4.1 Lead Vocals above.
• If you have enough tracks avail-
able, we recommend overdub-
bing each voice separately.
Backing vocals/technique 2:
• If you use a separate micro-
phone for each of several vo-
calists simultaneously, set each
microphone to hypercardioid (a
position between and )
to prevent crosstalk, particularly
if you place the microphones
close to one another.
Backing vocals/technique 3:
• Refer to fig. 8. If you use a sin-
gle microphone for the entire
group, select the cardioid
( ) or omni ( ) pattern and
place the vocalists in a semicir-
cle in front of the microphone.
• Place the microphone about 1 foot (30 cm) in
front of the instrument, slightly off the bell
axis.
• Switch the preattenuation pad in.
• To reduce blowing noise, a PF 80 pop screen
(available as an optional accessory) between
the microphone and
instrument.
a
b
B T A S
60°60°
H 50
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 11 (Schwarz/Black Auszug)

12 PERCEPTION 820 TUBE
4 Using the Microphone
4.4.4 Electric Guitar/Bass
Fig. 10: Electric guitar.
4.4.5 Violin, Viola
Fig. 11: Violin.
Electric guitar:
• Position the microphone 1 to
6 inches (2.5 to 15 cm) in front
of the speaker, aiming at a point
just off the speaker diaphragm
center.
• Use the bass cut and preattenu-
ation pad.
• You may want to use an addi-
tional distant microphone to cap-
ture the sound of the speaker
cabinet as it interacts with the
room.
Electric bass:
• Use the same technique as for the electric guitar.
• You can use a DI box to add the direct signal of the line output on the bass amp to the
microphone signal.
Solo violin:
• Set the polar pattern selector to
cardioid ( ) or omnidirectional
().
• Direct the microphone at the f
holes from a height of 6 to 8 feet
(1.8 to 2.5 m) above the floor.
Viola:
• Set the polar pattern selector to
cardioid ( ) or omnidirectional
().
• Direct the microphone to the f
holes from a height of 7 to
10 feet (2.2 to 3 m) above the
floor.
Large string sections:
• Use a combination of a main microphone in an XY, MS, ORTF, or other stereo configura-
tion and close-in spot microphones.
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 12 (Schwarz/Black Auszug)

13PERCEPTION 820 TUBE
4 Using the Microphone
4.4.6 Double Bass, Cello
Fig. 12: Double bass.
4.4.7 Acoustic Guitar
Fig. 13: Miking an acoustic
guitar with a single
microphone.
4.4.8 Flute
Fig. 14: Miking the flute with
a single microphone.
Double bass:
• Align the microphone with one
of the f holes from a distance of
about 16 inches (40 cm).
• If you need to record the double
bass together with an ensem-
ble, place the microphone
closer to the instrument and set
the polar pattern to hypercar-
dioid (turn the polar pattern se-
lector one notch CW from
cardioid ( )) to prevent leak-
age from other instruments into
the bass microphone.
Cello/technique 1:
• Refer to “Double bass” above.
Cello/technique 2:
• Use a close-in microphone as
in technique 1 above plus a distant microphone.
• Set the level of the close-in microphone approx. 20 dB lower than the distant mic level.
We recommend using two micro-
phones:
• Place one PERCEPTION 820
TUBE 8 to 12 inches (20 to
30 cm) away from the guitar
and aim at the sound hole.
• Aim a small-diaphragm micro-
phone (e.g., a C 451B) at a
point near the bridge from a
distance of about 3 1/2 feet
(1 m) or at the body from a
point below and to the rear of
the instrument.
We recommend using two micro-
phones:
• Place mic 1 above and to one
side of the player (to reduce
blowing noise) and align it with
the player's mouth
• Aim mic 2 at the instrument
from the side.
• Refer to fig. 14. If you prefer to
use a single microphone, place
the microphone about 7 to
8 1/2 feet (2 to 2.5 m) above
the floor and aim as mic 1
above.
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 13 (Schwarz/Black Auszug)

14 PERCEPTION 820 TUBE
4 Using the Microphone
• Point the microphone at the low-
est key.
• To minimize key noise, place the
microphone a little ways to the
side of the instrument.
• Aim the microphone at the mid-
dle of the instrument from a dis-
tance of about 2 to 3 1/2 feet
(50 cm to 1 m).
Grand piano:
• Aim a single PERCEPTION 820
TUBE or a stereo pair (see section
4.4.2 Choir) at the middle strings
from a height of 5 to 7 feet (1.5 to
2 m).
• For a rock/pop sound, place two
microhones roughly 8 to 16 in.
(20 to 40 cm) above the strings.
• Align mic 1 with the treble strings
and mic 2 with the bass strings,
both at a point about 6 inches
(15 cm) behind the dampers.
4.4.9 Clarinet
Fig. 15: Clarinet.
4.4.10 Tenor and
Soprano Saxophones
Fig. 16: Tenor saxophone (a),
soprano saxophone (b).
4.4.11 Grand and
Upright Pianos
Fig. 17: Grand piano.
a
b
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 14 (Schwarz/Black Auszug)

15PERCEPTION 820 TUBE
4 Using the Microphone
Fig. 18: upright piano.
4.4.12 Drums
Fig. 19: Typical drum kit.
Important!
Upright piano:
• Use the same technique as for
the grand.
• Open the lid and let the micro-
phones “peek into the instru-
ment” from above.
Overhead miking:
Refer to fig. 19.
• Place two PERCEPTION 820
TUBEs about 31 inches to
4 feet (80 to 120 cm) above the
drummer's head.
• Set each microphone to car-
dioid ( ) or omnidirectional
( ) mode.
• Use little or no EQ! This tech-
nique will pick up the entire kit,
delivering a highly natural
sound.
Cymbals:
To record cymbals on a separate
track, consider this technique:
• Place the microphone about
20 inches above and halfway
between the crash and ride cymbals.
• Set the polar pattern selector to figure eight ( ).
• Be sure to place the microphone out of reach of the drumsticks! The impact of a
drumstick hitting the microphone may break the heater filament and silence the
microphone. L
!
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 15 (Schwarz/Black Auszug)

16 PERCEPTION 820 TUBE
5 Cleaning
Important!
6.1 Replacing Fuses
Warning!
Fig. 20: Opening the fuse
compartment.
• To avoid electric shock, make sure to disconnect the Remote Control Unit from
power before cleaning the microphone or the Remote Control Unit.
1. Disconnect the power cord from the Remote control Unit.
2. To clean the surfaces of the microphone body and Remote Control Unit, use a soft cloth
moistened with water.
• Dangerous voltages may be present inside the Remote Control Unit. To avoid elec-
tric shock, injury, and fire, UNDER ALL CIRCUMSTANCES disconnect the power
cord from the Remote Control Unit before replacing a fuse.
• To avoid damage, replace blown fuses with new fuses of the same type and rat-
ing only.
The fuse protecting the primary circuit is located in the marked fuse compartment below the
AC input connector on the Remote Control Unit rear panel.
To replace the fuse,
1. Use a flat-blade screwdriver to open the fuse compartment lid.
2. Remove the blown fuse.
3. Insert a new fuse of the same type and rating (125 mA/250 V slow-blow).
4. Close the fuse compartment lid.
L
!
6 Troubleshooting
L
↯
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 16 (Schwarz/Black Auszug)

17PERCEPTION 820 TUBE
6 Troubleshooting
6.2 Solving Problems
Problem Possible Cause Remedy
No sound. 1. Power to mixer and/or recording
device is off.
2. Channel or master fader on mixer
or recording device is at zero.
3. Microphone is not connected to
mixer or recording device.
4. Cable connectors are seated
loosely.
5. Audio cable or audio/control cable
is defective.
6. No supply voltage.
7. Vacuum tube inside microphone is
defective.
8. Fuse blown.
1. Switch power to mixer and/or
recording device on.
2. Set channel or master fader on
mixer or recording device to de-
sired level.
3. Connect microphone to mixer or
recording device.
4. Check cable connectors for secure
seat.
5. Check cables and replace damaged
cable(s).
6. Check POWER LED. Switch power
to Remote Control Unit on.
Check audio/control cable and re-
place if necessary.
7. Contact your nearest AKG Service
Center.
8. Check POWER LED. Refer to sec-
tion 6.1 above or contact your
nearest AKG Service Center.
Distortion. 1. Channel gain control on mixer set
too high.
2. Microphone too close to sound
source.
3. Microphone sensitivity set too high.
1. Turn gain control down CCW.
2. Move microphone further away
from sound source.
3. Switch preattenuation pad in.
Crackling noises or low output. • Partial short circuits due to exces-
sive humidity.
• Place microphone in warm, dry
room and allow to dry.
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 17 (Schwarz/Black Auszug)

18 PERCEPTION 820 TUBE
7 Specifications
7.1 Microphone
7.2 Remote Control Unit
Type: 1-inch dual-diaphragm, true condenser pressure-
gradient microphone
Polar patterns: omnidirectional, cardioid, figure eight plus six
intermediate patterns (selectable on Remote
Control Unit)
Open-circuit sensitivity
at 1kHz (cardioid): 20 mV/Pa (-34 dBV ±3 dB)
Frequency range: 20 Hz to 20 kHz (see frequency response graphs)
Impedance: ≤ 200 ohms
Recommended load impedance: ≥ 1000 ohms
Equivalent noise level
to IEC 60268-4 (A-weighted): 16 dB-A
Signal/noise ratio re 1 Pa (A-weighted): 78 dB
Max. SPL: 135 / 155 dB SPL (0 / -20 dB)
Preattenuation pad: -20 dB (switchable on Remote Control Unit)
Bass cut filter slope: 12 dB/octave, 80 Hz
(switchable on Remote Control Unit)
Environment: temperature: -10°C to +60°C
R.H.: 80% (+25°C)
Powering: via Remote Control Unit only
Connector: dedicated 7-pin male XLR
Dimensions: 53 dia. x 212 mm high / 2 x 8.3 in.
Net weight: 870 g / 1.9 lbs.
Audio/control input: dedicated 7-pin female XLR connector
Audio output: standard 3-pin male XLR connector,
balanced, pin 2 hot
Polar pattern selector: 9-position detented rotary switch
Bass cut filter switch: 2-position toggle switch
Preattenuation switch: 2-position toggle switch
Power voltage: 210-240 VAC or 110-120 VAC, selectable
Primary fuse: 125 mA / 250 V slow-blow
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 18 (Schwarz/Black Auszug)

19PERCEPTION 820 TUBE
7 Specifications
Frequency Response Polar Diagram
Omni-
directional
Cardioid
Figure Eight
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 19 (Schwarz/Black Auszug)

20 PERCEPTION 820 TUBE
Sommaire
Page
1 Sécurité et environnement ........................................................................................................21
1.1 Symboles utilisés.................................................................................................................21
1.2 Consignes de sécurité..........................................................................................................21
1.3 Environnement ....................................................................................................................21
2 Description ................................................................................................................................22
2.1 Introduction.........................................................................................................................22
2.2 Fournitures .........................................................................................................................22
2.3 Accessoires optionnels.........................................................................................................22
2.4 Microphone.........................................................................................................................22
2.5 Unité de commande à distance .............................................................................................22
2.5.1 Face avant .................................................................................................................23
2.5.2 Face arrière................................................................................................................23
3 Réglage .....................................................................................................................................25
3.1 Remarque importante ..........................................................................................................25
3.2 Raccordement du microphone ..............................................................................................25
3.3 Raccordement au secteur de l’unité de commande à distance .................................................25
3.4 Mise sous tension................................................................................................................25
3.5 Mise hors tension ................................................................................................................26
4 Utilisation du microphone..........................................................................................................27
4.1 Introduction.........................................................................................................................27
4.2 Conseils généraux ...............................................................................................................27
4.3 Sélection de la directivité ......................................................................................................28
4.4 Conseils de positionnement du microphone ...........................................................................28
4.4.1 Soliste vocal ...............................................................................................................28
4.4.2 Chorale/Choristes .......................................................................................................29
4.4.3 Trompette, trombone...................................................................................................30
4.4.4 Guitare électrique/Guitare basse ..................................................................................30
4.4.5 Violon, alto..................................................................................................................30
4.4.6 Contrebasse, violoncelle ..............................................................................................31
4.4.7 Guitare sèche .............................................................................................................31
4.4.8 Flûte traversière..........................................................................................................32
4.4.9 Clarinette ...................................................................................................................32
4.4.10 Saxophones ténor et soprano.....................................................................................32
4.4.11 Piano à queue/Piano droit..........................................................................................33
4.4.12 Batterie....................................................................................................................33
5 Nettoyage ..................................................................................................................................34
6 Dépannage ................................................................................................................................34
6.1 Remplacement du fusible .....................................................................................................34
6.2 Solutions aux problèmes ......................................................................................................35
7 Caractéristiques techniques......................................................................................................36
7.1 Microphone.........................................................................................................................36
7.2 Unité de commande à distance .............................................................................................36
Réponse en fréquence et directivité..............................................................................................37
Conformité ...................................................................................................................................38
Perception_820_Manual_final4_C030818 02/05/2009 11:26 Seite 20 (Schwarz/Black Auszug)