HEVOS 400T User manual

HEVOS
Owner’s manual
400T
amplifier

Safety instructions
1. This amplifier is supplied with ~230V or ~115V. Connect the amplifier
exclusively to a power point with earth connection. Never open the
amplifier. Repairs are exclusively done by Hevos and by companies that
have been authorized by Hevos. Otherwise the warranty will become
void.
2. The amplifier should not be used outdoors. Avoid exceptionally warm
places, places that are dusty or dirty and places of high humidity .
3. If the power cable is damaged, the amplifier has been dropped or the
amplifier is not working correctly immediately switch off the amplifier and
disconnect it from the power point. The amplifier should be repaired by an
authorized company only.
4. Never pull out the plug by the cable.
5. For cleaning, only use a dry soft cloth. Never use any water or chemicals.
6. In case of illicit or wrong use, wrong connection, wrong control or repair
by a non-authorized company or person the warranty will become void as
well.
7. Whenever you want to dispose of the amplifier, hand it in at your local
recycling company.
8. Never connect the Line Out to a mixing desk with Phantom Power
switched on! This can cause amplifier malfunction or even damage.

Introduction
The 400T is a transistor amplifier with a continues power of 400 Watts. The 2
inputs have separate gain controls. The led above input 1 is a clip indicator
which turns from green into red as soon as the input signal is too high. If so,
one should reduce the input signal by lowering the volume of the instrument or
the input gain at the amplifier.
Input 1 has a –6dB switch to reduce sensibility if necessary. This could be the
case by using an active bass guitar or double bass with separate pre-amp. If the
clip indicator turns into red often, one should put the switch to –6 dB. The –6
dB switch is also useful to connect both an active and passive bass at the same
time. If both basses have a similar output, the switch should be set to 0 dB.
Input 1 is provided with a phase turn switch, which can be useful connecting a
double bass with two different pick ups. By means of the switch one puts one
pick up out of phase, resulting in a different sound.
The pre amp is also equipped with a Mute Out to tune the instrument
soundlessly. By means of the Mute Out switch one can activate the Mute Out.
The internal signal is then interrupted and will be available at the Mute Out to
be sent to a tuning gear.
The tone control unit is a 4-band type and is very easy to use. The frequencies
are 80, 250, 800 and 2500 Hz , +/- 12 dB. The amplifier has been built in such a
way that in normal acoustic circumstances there will be no need to use the
tone control.
At the back are a Loudspeaker output, a Headphone output and a symmetrical
Line Out with pre/post switch. The pre/post switch controls the point in the
amplifier circuit where the line out signal comes from. Pre comes just behind
the input and is not controlled by gain nor tone control, post comes behind the
tone control. Never connect the Line Out to a mixing desk with Phantom Power
switched on! This can cause amplifier malfunction or even damage.
The loudspeaker output has a minimal load of 4 Ohms. Built in a combo one
can connect an extra loudspeaker cabinet of 8 Ohms. Together with the
internal loudspeaker of 8 Ohms one has a total load of 4 Ohms, forcing the
power amp to give its maximal power of 400 Watts. The headphone can be
controlled by means of the gain and master knob.

The 400T has a built-in delay and is protected against short circuit and clipping.
The 400T is powered by a class-D power amplifier with UcD technics, resulting
in an extremely stable amplifier which works noiselessly. The high efficiency of
the class-D power amp makes any cooling redundant.
Installation directions for use
1. Connect the amplifier exclusively to a power-point with earth pin.
2. When you connect or disconnect your bass, take care the Gain knob is
put to 0 or use the Mute switch to avoid switch clicks.
3. In order to set a distortion-free amplification it is advised to open the
Master knob ¾ to full. After that the volume is controlled by using the
Gain knob.
4. Under normal acoustical circumstances there is no need to use the tone
controls. However, if one should use the tone controls, it is advised to do
so carefully. Each tone control goes up to +12/-12 dB. The sensitivity
increases while turning the knob clockwise and anticlockwise.
5. The minimal impedance of an extra loudspeaker cabinet (400T in
combo) is 8 Ohms.
6. The minimal impedance of the stand alone 400T amplifier is 4 Ohms.
7. Only use a loudspeaker cable of excellent quality.

Control panel front
1. –6dB switch: reduces the sensibility of Input 1
2. Phase turn switch: puts one pick up out of phase when using 2 pick ups
(double bass).
3. Input 1
4. Gain Input 1: controls the signal amplitude towards the pre amp.
5. Input
6. Gain Input 2: controls the signal amplitude towards the pre amp.
7. Mute switch: activates the Mute-Out at the back.
8. Low: tone control 80 Hz, ± 12 dB, Q = 0,5
9. Low-Mid: tone control 250 Hz, ± 12 dB, Q = 0,5
10.Mid-High: tone control 800 Hz, ± 12 dB, Q = 0,5
11.High: tone control >2500 Hz, ± 12 dB, Q = 0,5
12.Master: controls the signal amplitude to the power amp.
13.On/Clip led: green at power-on. Red when the input signal is too high.
14.Led Mute-Out

Control panel back
1. Loudspeaker output: to connect loudspeaker cabinet(s) with a minimal total
impedance of 4 Ohms, or built in a combo, to connect an extra cabinet of
minimal 8 Ohms.
2. Line-out: symmetrical XLR-output to PA/mixing console.
3. Pre/post switch: taps the line out signal from pre-Gain or from post-Tone
Control position.
4. Headphone output
5. Mute-Out: connector for tuning gear.
6. Ground Lift switch: cuts the earth between amplifier and PA/mixing console
if necessary.
The power connector has a built-in fuse and spare fuse. The fuse box can be
opened with a screw driver.
Besides there is a voltage switch at the back of the amp.
The appropriate voltage of your country is set as a default. Changing the
voltage can damage the amplifier irreparably.

Technical features
Type: transistor/class-D MosFet bass amplifier
Power: 400 Watts into 4 Ohms, 1 kHz, < 0,01% distortion
Damping: > 2000 at 100 Hz in 4 Ohms
Input: 2x, both to be used independently.
Tone control: active, 4 band: 80, 250, 800, and >2500 Hz +/-12 dB
Protection: short circuit, DC current on output, mismatch and open end; clip
indicator; delayed power switch.
Divers: Mute Out; symmetric Line Out with pre/post switch, Headphone Out,
Ground Lift.
Output: Loudspeaker, Line Out, Mute Out, Headphone

Product warranty and service
This product is guaranteed against defects of used materials and operation from
the moment of purchase during a period of one year. If during this warranty
period this product does not function properly, Hevos will fit the product to the
use it is intended for without passing on the costs of labour and materials to the
purchaser under the following strict conditions:
Conditions:
1. The obligation of Hevos is restricted to the repair or replacement of
defects. Hevos is at liberty to decide whether it should be repair or
replacement. Transport costs are at the purchaser’s expense. Hevos cannot
be held responsible for any kind of risk during transport (e.g. loss, damage
etc).
2. All repairs under warranty should be done by Hevos or a company that has
been authorized by Hevos. Repairs by non-authorized companies are no
part of this warranty. If the product is damaged due to non-authorized
repairs then this warranty will become void.
3. This warranty applies only for defects of used materials and operation. The
warranty does not apply for:
damage caused by lightning, induction, faulty power supplies, faulty
power cords, insufficient ventilation, flooding, fire, smoke, peace
disturbances hooliganism and war.
damage caused by accidents, negligence, modifications and wrong
use or wrong installation or wrong transport
products with illegible serial numbers or numbers that have been
tampered with
4. The warranty expires when the product is hired, lent or sold to third
parties.
Specifications and information contained in this manual are furnished for
informational use only, and are subject to change at any time without notice
and should not be construed as a commitment by Hevos. Hevos assumes no
responsibility or liability for any errors inaccuracies that may appear in this
manual.
Panningen
The Netherlands
Email: [email protected]
URL: www.hevos.nl