IMPORTANT SAFETY INSTRUCTIONS
Exposure to extremely high noise levels may cause permanent hear-
ing loss. Individuals vary considerable in susceptibility to noise-induced
hearing loss, but nearly everyone will lose some hearing if exposed to
sufficiently intense noise for a period of time. The U.S. Government’s
Occupational Safety and Health Administration (OSHA) have specified the
permissible noise level exposures shown in the following chart.
According to OSHA, any exposure in excess of these permissible limits
could result in some hearing loss. To ensure against potentially danger-
ous exposure to high sound pressure levels, it is recommended that all
persons exposed to equipment capable of producing high sound pressure
levels use hearing protectors while the equipment is in operation. Ear
plugs or protectors in the ear canals or over the ears must be worn when
operating the equipment in order to prevent permanent hearing loss if ex-
posure is in excess of the limits set forth here.
Duration, per
day in hours
Sound Level dBA,
slow response
Typical example
890 Duo in small club
692
495 Subway train
397
2100 Very loud classical music
1.5 102
1105 That couple screaming
at each other
0.5 110
<0.25 115 Loudest parts at a rock concert
The CLA-400 complies with all applicable / RoHS / WEEE European
Union directives. This product complies with IEC62386.
Do not attempt to service this unit yourself, as it will void your war-
ranty. Please check your unit carefully upon receipt and return to place of
purchase immediately if there are any problems with the product. After
that, the standard AVANTONE 5 YEAR warranty will apply to defects in
materials and workmanship.
U.S.A.
Should your Avantone product require service, please contact the Avan-
tone PRO Service Department. +1 845 642 3697-or- e-mail info@avan-
tonepro.com. You must obtain an RA # (Return Authorization number)
from us before shipping a unit back to us. This RA # must be clearly
written on the outside of the box.
Please safely pack the units…It is best to use the original packing mate-
rials. AVANTONE PRO cannot be responsible for any damages incurred
in shipping to us due to poor packaging. PLEASE PACK CAREFULLY and
FULLY INSURE THE SHIPMENT.
INTERNATIONAL
For service or warranty assistance, please contact the AVANTONE PRO
distributor in your country through the dealer from whom you purchased
this product.
LIMITED 5 YEAR WARRANTY
AVANTONE CLA-400s are warranted by Avantone Pro to be free from
defects in materials and workmanship for the period of 5 YEARS to the
original purchaser. In the event of such defects, the Avantone Pro product
will be repaired without charge or, at our option, replaced with a new one
if delivered to Avantone Pro prepaid, together with a copy of the sales slip
or other proof of purchase date. The warranty excludes problems due to
normal wear, abuse, shipping damage or failure to use the product in ac-
cordance with the specifications.
All speaker systems are vulnerable to damage from sustained amplifier
clipping. This can be described as a distortion of the signal caused by the
amplifier running out of headroom. Heat will then be generated in the
voice coil of the driver beyond the heat handling capabilities of wire and
glue. At some point the voice coil will burn, causing the speaker to sound
very distorted; eventually the driver will stop working.
All parts and labor are covered under this Limited Warranty. However, if it
is determined by AVANTONE PRO that the voice coil was burned due to
sustained amplifier clipping, we reserve the right to charge the customer
for the cost of the repair, since this is considered abuse.
Avantone Pro shall not be liable for damages based upon inconvenience,
loss of use of the product, loss of time, interrupted operation or com-
mercial loss or any other damages, whether incidental, consequential, or
otherwise. This warranty gives you specific legal rights, and you may have
other rights, which will vary from state to state.
This warranty is not transferable.
The Avantone Pro CLA Studio Reference Amplifier is a classically designed
Class A/B amplifier. We took particular care to create an amplifier in the
traditional studio style, with generous VU meters, high quality Japanese
components and a serious toroidal transformer linear power supply. In
a standard 3U rack mount chassis, this amplifier can generate over 360
watts per channel into an 8 ohm load, making it perfect for large speakers
in a studio environment. The CLA-400 is convection cooled – no fan noise,
so it can be used in the same room as the monitors.
The CLA-400 Studio Reference Amplifier is designed to be used in a studio
environment requiring high power output with no fan noise. Under test-
ing, it delivers a powerful 360 watts into 8 ohms and can run at one third
power without thermal fault.
The CLA-400 was designed to be paired with large format studio moni-
tors, but it can be used with just about any demanding speaker load. Very
low distortion, steady performance under harsh conditions, and an open
and transparent sound make this an obvious choice for discerning studios.
INTRODUCTION
CONNECTING YOUR CLA-400
Before plugging in and powering up your CLA-400 please take a
moment to be certain that the proper AC MAINS operating voltage
setting has been selected on the rear panel.
INSTALLATION AND MOUNTING
The CLA-400 is a 3U amplifier that can be can mounted in a standard
19-inch rack. Four front panel mounting holes are provided.
THERMAL PROTECTION
If the heat sink temperature reaches an abnormally high temperature, the
amplifier will protect itself by disconnecting loudspeakers and shutting
down until sufficiently cooled.
DC VOLTAGE PROTECTION
If an amplifier channel detects DC voltage at its output terminals, the out-
put relay will immediately open to prevent loudspeaker damage.
SHORT CIRCUIT
If an output is shorted ( i, e.. defective speakers or crossed speaker wires)
the ZSP and thermal protection circuits will automatically protect the am-
plifier. The ZSP circuit senses the short circuit as an extremely stressful
load condition and attenuates the signal, protecting the channel’s output
transistors from over current stress. If the short circuit remains, the load
will be disconnected by the thermal protection circuit.
ö Select the operating voltage. If you are chang-
ing voltages, please be sure to change fuse
values as specified on the rear panel
ö Select operating mode: either two indepen-
dent channels or mono bridged mode.
ö Place volume controls to minimum
ö Connect audio input, speaker cables and pow-
er cord with power switch in OFF position
ö Plug power into AC source
ö Turn on all upstream equipment; run outputs
at minimum
ö Turn on power switch
ö Adjust volume to appropriate level at source
and speaker
QUICK START GUIDE
1. BALANCED INPUT: The XLR and phone plug inputs accept a BALANCED
male XLR plug as well as a 3-conductor BALANCED TRS ¼” or a 2 con-
ductor UNBALANCED TS ¼” male plug. For unbalanced operation with a
TS connector the minus signal is automatically grounded. A pass-through
connection is provided for convenience when running multiple amplifiers
on the same signal chain.
2. VOLTAGE SELECT and AC MAINS INPUT: There is a switch on the
rear panel for selecting the proper AC/MAINS operating voltage for your
location. Please be sure to use the correct specified fuse value for your
location. Fuse tray is incorporated into the IEC320 receptacle on the rear
panel.
3. GROUND LIFT Switch: By engaging this switch the pin 1 shield is lift-
ed at the input jack and routed through two opposing diodes. This can
be used to aid in ground loop control of the incoming analog line signal.
The diode signal path still provides a safety ground in the event of very
high voltage ground loops. The earth ground from the AC input is always
connected. If the ground lift switch doesn’t help, it may be necessary to
evaluate your power/ground scheme to eliminate noise issues.
4. SPEAKER OUTPUTS: Both SPEAKON™ and binding posts are provided.
In mono/bridge operation mode, the two positive terminals are driven an-
ti-phase. DO NOT GROUND any of the speaker terminals in bridge mode.
5. MODE SWITCH: DO NOT ADJUST THIS SWITCH WITH POWER ON.
This switch allows the user to operate the amplifier in three modes:
STEREO: both channels driven separately
PARALLEL: the input is sent to both outputs; volume controls
are still enabled for each channel
BRIDGED MONO: both channels operate together as a sin-
gle amplifier. Channel A is the input, and Channel A output is
in phase, channel B output is out of phase.
REAR PANEL CONNECTIONS
12 3 4 5
