Hughes & Kettner ATS 120 User manual

Congratulations on the purchase of
your Hughes
& Kettner ATS 120!
The ATS 120 has been developed to combine optimum sound quality and flexibility with
simple, user-friendly operation.
The ATS 120‘s design makes the majority of functions self-explanatory. This user
manual is intended to give you an overview of all the possibilities and features of the
amplifier.
Enjoy your ATS
120!
Front panel control elements
(1) INPUTS: sockets for connecting your instrument cable.
Nowadays, many different electric guitars are available, ranging from the classic Strat
with its “single coil” pickups to modern designs incorporating very high power active
humbucking units. To ensure that all types of pickups can be ideally matched to the
preamp of the ATS 120, two inputs are provided with different sensitivity ratings.
LO: Input for guitars fitted with high output / active pickup systems.
HI: Input for guitars fitted with traditional passive pickup systems.
The ATS 120‘s three channels
The Hughes & Kettner ATS 120 offers three separate channels, each of which has it‘s
own distinctive sound characteristics. The individual channels offer a wide variety of
different sounds thanks to their independent GAIN /VOLUME controls and
equalisation sections.
Selecting a channel
Above the individual VOLUME or GAIN control of each channel (Clean - Volume,
Crunch
- Gain and Lead - Gain) there is a pushbutton which is used to activate it.
The active channel is indicated by an arrow-shaped LED. When using the CRUNCH
and LEAD channels, different coloured LED arrows are used to indicate which GAIN
and MASTER controls are operational.

The ATS 120 Clean channel
The CLEAN Channel is a “solid state” (i.e. transistor) design. This provides the moderr,
crystal-clear sounds popular with contemporary recording artists. However, tht
traditional , passive three-band equalisation controls and the “Soft-Click” circuitry make
it possible to reproduce the mild distortion characteristics of a vintage valve amplifier.
The “Soft Click” circuit prevents hard-sounding, unattractive transistor distortion and
provides pleasant, lightly distorted clean sounds at higher gain settings.
(2)
VOLUME :
determines the volume of the CLEAN channel. At settings around 8 or 9, mildly
distorted “clipped” rhyhm sounds can be produced from single coil pickups. Higher
output pickups will produce a similar effect at a correspondingly lower setting.
(3)
BASS, MID, TREBLE :
the CLEAN channel‘s three tone controls can be used to generate a wide variety of
different clean sounds. Start from the standard setting (Bass, Mid, Treble all at the 12
o‘clock position ) and alter the positions to suit your taste.
(4) BRIGHT:
activating the BRIGHT switch gives additional boost to the very high, shimmering
harmonics present in the clean channel.
The ATS 120 Crunch channel
The CRUNCH channel of the ATS 120 is a tube design, offering the distinctive
characteristics of traditional tube amplifiers. Depending of the GAIN setting chosen
and the type of pickups being used, CRUNCH provides a broad spectrum of valve
sounds, from clean to overdrive.
The CRUNCH channel on the ATS 120 has an extremely broad dynamic range, the
degree of distortion generated can be very finely adjusted by varying your attack and the
volume setting on the guitar itself.
(5) CRUNCH GAIN:
determines the input sensitivity, thus matching the channel to the pickup output. Low
GAIN settings make it possible to produce clean to lightly distorted sounds; a high
setting produces the classic valve overdrive sounds.
(6)
CRUNCH VOL.:
controls the CRUNCH channel‘s volume in relation to the Clean and Lead channels.

(1)
(2)
(4) (3) (5)
0 (5) (10)
The ATS 120 Lead channel
(7) LEAD GAIN:
determines the input sensitivity of the LEAD channel, allowing fine tuning of the degree
of distortion and the intensity of the compression effect typical for tubes.
(8)
LEAD FAT:
The LEAD FAT switch only affects the LEAD channel, it makes the lead sound fuller.
Even “thin”-sounding guitars can be given noticeably more punch by using the LEAD
FAT function.
(9)
LEAD VOL:
the LEAD VOL. control determines the LEAD channel‘s volume relation to the Clean
and Crunch channels, without altering the character of the sound.
The tube channel‘s equalisation section (10)
CRUNCH and LEAD have a shared four-band active equalisation section which can be
used to cut and boost the amount of particular frequencies present in the signal. The
sound of each channel is carefully tuned to ensure that using a particular setting for
both of them will produce a natural-sounding transition.
BASS: controls the bottom end fundamentals of the sound, giving it punch.
Approx. +/- 10
dB at 120 Hz
MID: controls the amount of sustain available and the penetration characteristics.
Approx. +/- 12 d B at 850 Hz
TREBLE: provides precise control over the “cut” and bite of the guitars sound.
Approx. +/- 10 dB at 4,2 kHz
PRESENCE: controls the harmonic content, providing crisper Crunch and searing
Lead. Approx. +/- 16
dB at 12 kHz.

(6) (9) (11) (12) (13) (14)
The Reverb. FX- and Master Section of the ATS 120
An ACCUTRONICS spring system is used to produce the reverb effect in the ATS 120.
The quality of a reverb unit depends largely on the length and number of springs used;
this genuine Accutronics unit generates a warm, realistic effect for the ATS 120 by
having three particularly long springs.
Increasing the degree of distortion on an overdriven sound will tend to make it more
sensitive to reverb; in other words, too much reverb can easily swamp the sound. For
this reason, the reverb effect is differently tuned for each of the three channels. When
you change channels, you will not need to alter the reverb setting to achieve a
similar-sounding effect.
(11)
REVERB:
controls the amount of tuned reverb for CLEAN, CRUNCH and LEAD.
(12) FX-MIX:
determines the relative volumes of the original sound and the signal from an external
effects unit connected to the effects loop. DRY= only original signal; FX= only
processed signal. Intermediate setting allow the proportions of original and
processed
signals to be balanced as desired.
TIP: If no external unit is connected up, the FX-MIX control can be used in conjunction
with the ATS STAGEBOARD (optional) to set up an alternative master volume setting.
This can then be called up using the ATS Stageboard.
PROGRAMMING A SECOND MASTER VOLUME SETTING: select the channel or
channels for which you wish to program an alternative volume setting. This is done by
turning the appropriate FX-SELECT switch or switches to the ON position (there are 3
located on the rear panel of the ATS 120). Activate the
EXT.FX function on the ATS
Stageboard. Set the desired volume level using the FX-MIX control. By turning the
EXT. FX switch ON/OFF, you can now cycle between the two different master volume
settings.
(13)
MASTER: controls the overall volume of the ATS 120.
(14) MAINS: power on/off switch. When switched on, the red LED arrow will be
illuminated.

(15) / (16) / (17) (18) (19)
The rear panel on the ATS 120
(15) MAINS LEAD SOCKET
point for connecting the euro mains lead included with your amplifier.
(16) FUSE:
safety holder for the mains fuse (AT 1250mA). The fuse holder can be removed by
depressing its fixings on both sides. The fuse can then be changed.
(17) VOLTAGE SELECTOR, 220-240 VOLTS:
on all European models, the ATS 120 can be set to operate on either a 220 or 240 volt
supply by rotating the insert incorporated in the fuse holder. The value visible in the
fuse holder‘s window is the one which is operative.
Models for North America and Japan are equipped at the factory with different
transformers which are pre-set to the appropriate mains voltage standards.
(16)
SPEAKERS:
the ATS 120 has two sockets for connecting loudspeakers or cabinets. The combined
impedance of all loudspeakers used must never be less than 4 Ohms!
The loudspeaker fitted to the combo version has an 8 Ohms impedance. Any further
speaker cabinet connected to it should have an impedance of either 8 or 16 Ohms.
For the ATS 120 Head: if a single speaker cabinet is used, its impedance should be
either 4 Ohms or 8 Ohms. When two cabinets are used, each one should have an
impedance of either 8 or 16 Ohms.
(19) HEADPHONES:
socket for standard stereo headphones. The frequency response of the signal fed to the
headphone socket is tailored to reproduce the characteristics of a typical guitar speaker.
This produces a “comfortable” sound which is suitable even for lengthy practice sessions.
(20)
POWER AMP IN AND LINE OUT:
these two sockets have a variety of uses. LINE OUT: this provides access to the
preamplifier signal (before the poweramp), which can then be send to a mixing console

(20) (21) (22)
(23)
via a RED BOX. This socket can also be used to send the preamplifier signal to an
external power amp or to additional guitar amplifiers.
LINE OUT AND POWER AMP IN: used together the two sockets can provide an
extra loop for connecting external effect units. When used this way, LINE OUT
corresponds to the SEND socket (towards the effect unit) and
POWER AMP IN to the
RETURN socket (back from the effects unit to the amplifier).
POWER AMP IN: this allows external preamps to be connected up as alternatives to
those built into the ATS 120. Their volume can be determined using the MASTER
control. When the
POWER AMP IN socket is in use, the internal preamplifiers are
automatically switched out of circuit.
(21)
FX LOOP:
the FX LOOP is specially designed for use with external effects devices. The SEND
socket is connected to the INPUT of the effects unit, and the RETURN with the
OUTPUT. The -lOdB PAD switch adjusts the sensitivity of the loop to make it
compatible with different units (OFF=
1V / ON= 300 mV, suitable for f.e.
floor-standing effects units).
TIP! The loop can also be used to connect a second instrument or a tape for playback.
This means that when
practicing an additional instrument, drum machine or a tape
recorder can be connected to the RETURN socket. Once the FX SELECT switch has
been set to the ON position, the volume can be determined using the FX-MIX control.
(22) THE EFFECTS MATRIX ON THE ATS 120: FX-SELECT:
The three mini switches on the FX SELECT matrix are used to allocate a connected
external effects unit to particular channels. ON indicates that the effects unit will be
activated. By using these presets, a channel change from CLEAN to LEAD (for
instance) will activate the effect without the need for extra switching procedures.
If, as described under point 12, the FX MATRIX is being used to pre-programme an
additional master volume setting, the
FX SELECT switch relating to the appropriate
channel (s) must be in the ON position.
(23) STAGEBOARD:
this 9-pin socket is used to connect the ATS 120 Stageboard, available as an optional
accessory. Switching facilities: CLEAN/CRUNCH/LEAD/REVERB/EFFECT.

ATS 120 Connections
EFFECTS UNIT, or for practice: 2nd Instru-
EXTERNAL POWER AMPLIFIER and
ment, tape recorder, drum machine.
connected speaker cabinet (s).
INPUT OUTPUT
INPUT
II
I
FX SEND
FX RETURN
LINE OUT OR
SPEAKERS
STAGEBOARD
LINE OUT
LINE OUT Signal for PA- and
Recording/Studio applications.
SPEAKERS INPUT
When a single cabinet is being
used, its impedance must be 4 or 8
Ohms.
When two cabinets are being used,
the impedance of EACH cabinet
must be 8 or 18 Ohms.

ATS 120 Sound Examples
The examples shown here are only intended as general illustrations, because they are
strongly affected by the instrument used and your individual playing style. However,
these settings will give you an initial overview of the range which the ATS 120 is
capable of producing.
l.TOP 40 SET
CLEAN CRUNCH & LEAD
VOL. BRI. BASS MID TREB CRU. GAIN LEA. GAIN L. FAT BASS MID TREB. PREC. CR. VO. LEAVO. REV MASTER
6
ON 10 556
8 -
+3 -1 +2
065
4 5
2. THE FUSION SET
2.CLEAN
CRUNCH & LEAD
MID TREB. PREC. CR. VO. LEAVO. REV. MASTER
8
--_ 10
7 5 7.5 7
ON
+3 +3 0
6 7
6.5 35
3. THE METAL SET
CLEAN CRUNCH & LEAD
VOL. BRI. BASS MID TREE. CRU. GAIN LEA. GAlb L. FAT BASS MID TREB. PREC. CR. VO. LEAVO. REV. MASTER
6ON 10 610
6.5
10 - +3 +1 +3
+3 +2 6.5 6
5.5
4. THE ROCK SET
CLEAN
CRUNCH & LEAD
VOL BRI. EASS MID TREK CRU. GAIN LEA Gain L FAT BASS MID TREE. PREC. CR. VO. LEAVO. REV. MASTER
7
ON 10
7 10 10
8ON
+l +2 +1++11+1+1
76-76-7 45

Care of your amplifier and guarantee conditions
A WORD ABOUT VALVES:
Valves need to reach a certain operating temperature. They need a few seconds after the
power has been switched on to warm up before they will work.
Valves are sensitive to shock. Once you have switched the amplifier off, give it a few
minutes to cool down before transporting it.
The sound characteristics of valves will also tend to change with time. Occasionally, they
will need replacing. The ECC 83 valves used in the
ATS 120 are some of the most
commonly used, and the most affordable. Generally speaking, a change of valves is only
necessary every few years.
Before opening the amplifier casing, ALWAYS remove the mains plug!
WHERE TO USE THE AMPLIFIER:
do not use the unit under the following conditions:
*
extremes of temperature or high humidity
poor ventilation or insufficient cooling
extreme vibrations or impacts
SERVICING AND REPAIRS:
If your amplifier suffers a failure or fault, refer the matter to your authorised Hughes &
Kettner dealer. Do not try to rectify the problem yourself; servicing and repairs are jobs
for experts. Please note: any interference with the amplifier by unauthorized persons or
workshops will render your guarantee invalid.
GUARANTEE CONDITIONS:
Every Hughes & Kettner product is accompanied by a warranty card showing its serial
number and a card showing proof of inspection.