AVANTONE PRO PRO CLA-400 Power Amplifier User Guide
- June 14, 2024
- AVANTONE PRO
Table of Contents
AVANTONE PRO PRO CLA-400 Power Amplifier
Product Information
Specifications
- Power Output (10% rated power at 1KHz): 360W
- Power Output (540W at 10% rated power) : 540W
- Power Output (760W at 10% rated power) : 760W
- Slew Rate : 28V/us
- Input Sensitivity: 0.775V (0dBU)
Product Usage Instructions
Connecting Power/Circuit Size Requirements
It is crucial to follow the correct procedure when connecting the amplifier
to power to ensure proper functioning and avoid any damage. Please adhere to
the following steps:
- Before making any audio connections, always turn off and disconnect the amplifier from the main voltage.
- Ensure that the AC voltage you are connecting the amplifier to is within the specified range mentioned in the user manual.
- As an extra precaution, keep the volume controls turned down during power-up to prevent any sudden loud noises or potential damage.
Cooling Requirements
To maintain optimal performance and prevent overheating, it is important to
ensure proper cooling for the amplifier. Follow these guidelines:
- Place the amplifier in a well-ventilated area with sufficient airflow.
- Avoid blocking the ventilation slots or placing the amplifier in enclosed spaces.
- Regularly clean the ventilation slots to remove any dust or debris that may obstruct airflow.
Frequently Asked Questions (FAQ)
What happens if I connect the amplifier to improper AC voltage?
Connecting the amplifier to improper AC voltage can cause damage to the
device. It is important to ensure that the AC voltageis within the specified
range mentioned in the user manual to avoid any warranty void and potential
damage.
Why should I have the volume controls turned down during power-up?
Having the volume controls turned down during power-up is an extra
precautionary measure to prevent any sudden loud noises that may occur when
the amplifier is being powered on. This helps protect your speakers and
ensures a smooth start-up process.
OVERVIEW
INTRODUCTION
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.
QUICK START GUIDE
- Select the operating voltage. If you are changing voltages, please be sure to change fuse values as specified on the rear panel
- Place volume controls to minimum
- Connect audio input, speaker cables and power cord with power switch in OFF position
- Plug power into AC sourceSelect operating mode: either two independent channels or mono bridged mode.
- Turn on all upstream equipment; run outputs at minimum
- Turn on power switch
- Adjust volume to appropriate level at source and speaker
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.
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 output
relay will immediately open to prevent loudspeaker damage.
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.
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
amplifier. 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.
REAR PANEL CONNECTIONS
-
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 conductor 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. -
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. -
GROUND LIFT Switch:
By engaging this switch the pin 1 shield is lifted 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. -
SPEAKER OUTPUTS:
Both SPEAKON™ and binding posts are provided. In mono/bridge operation mode, the two positive terminals are driven anti-phase. DO NOT GROUND any of the speaker terminals in bridge mode. -
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 single amplifier. Channel A is the input, and Channel A output is in phase, channel B output is out of phase.
CONNECTING POWER/CIRCUIT SIZE REQUIREMENTS
Damage caused by connecting the amplifier to improper AC voltage is not covered by any warranty. Note: Always turn off and disconnect the amplifier from main voltage before making audio connections, and as an extra precaution, have the volume controls turned down during power-up.
COOLING REQUIREMENTS
The power amplifiers use a convection cooling system to maintain an even
operating temperature. Air enters through the vents on each side and the
bottom of the amplifier chassis and exits through the sides and top of the
chassis. Make sure that there is enough space around the sides of the amp to
allow the heated air to exit. If the amp is rack-mounted, do not use doors
unless you have forced air cooling. Note: Whatever type of rack you are using,
make sure that the heated air can escape freely, and that there is no
resistance to the intake of cool air through the chassis.
SPECIFICATIONS
- Ω Stereo Power (1KHz): 360W
- 4Ω Stereo Power (1KHz) : 540W
- 8Ω Bridge Power (1KHz): 760W
- Slew rate (at 1KHz): 28V/us
- Input Sensitivity (1KHz): 0.775V (0dBU)
- Total Harmonic Distortion (1KHz) : <0.1%
- Intermodulation distortion (at 10% rated power 1KHz) : <0.1%
- Crosstalk : -70dB
- Frequency Response : 20Hz-20kHz +/-0.5dB
- Frequency Response: 20Hz-20kHz +/-0.5dB
- Input Impedance : (Balanced) 20KΩ (Unbalanced) 10kΩ
- Damping Factor(100Hz, 8Ω) : 250
- Signal to Noise Ratio (A Weighted): >103dB
- Amplifier : Class AB
- Dimensions : 483Wx133Hx487D (19”x5.25”x18”)
- Weight : 22.2kg (49lb)
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
---|---|---
8| 90| Duo in small club
6| 92|
4| 95| Subway train
3| 97|
2| 100| Very loud classical music
1.5| 102|
1| 105| 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.
www.avantonepro.com Avantone Pro Po Box 748 Tallman NY 10918 +1 845 642 3697