MA3 Multichannel Amplifier
on August 31, 2015
- 3 Independent Amplifiers
- 60W per Channel Continuous Average Power into 4Ω, 20-20k Hz
- 40W per Channel Continuous Average Power into 8Ω, 20-20k Hz
- Load Sensitive Dynamic Limiters and Headroom Meters
- SPiKe® Protection Circuitry
- High Capacity Linear Power Supply
- Sealed Heat-Tunnel Forced-Air Cooling
- 80 Hz High Pass Filter Selection per Channel
- UL / cUL Certified
This product has not been tested to the current CE requirements and is not available in markets requiring CE compliance.
MA3 Multichannel Amplifier
The MA3 is a three-channel amplifier designed to operate reliably in commercial environments. This amplifier was specifically designed for use in:
- Foreground Music
- Background Music Distribution
The MA3 is an ideal amplifier with Rane’s paging, foreground music, and background music products, the Rane CP52S
and DA 26S
The MA3 uses a conventional linear power supply with a toroidal transformer. This configuration minimizes the emissions associated with switching supplies and noisier transformer designs. The power supply features independent secondary supplies for each channel
, minimizing load regulation interaction and crosstalk.
The combination of a solid, conservative power supply and forced-air cooling allows the MA 3 to simultaneously deliver 40 watts of continuous average power into 8Ω and 60 watts into 4Ω.
SPiKe®* dynamic protection circuitry completely safeguards each channel against over-voltage, under-voltage, overloads, transients from inductive loads, thermal runaway and instantaneous temperature peaks. Biasing is not allowed to occur when an under-voltage condition exists, reducing turn on and turn off transients.
Fast-response limiters allow the MA3 to tolerate up to 20 dB of overdrive into 8 and 4Ω loads while holding THD below 1%. This means no loss of speech intelligibility or harsh clipping. This feature greatly increases the dynamic range of the system without external limiters.
Peak-responding, load-adaptive meters accurately indicate the remaining headroom. The meters are helpful in setting system levels and indicating signal compression.
Balanced inputs with Euroblock connectors are provided. Euroblock output connectors accept up to 12 gauge wire. Rear panel Level controls allow amplifier sensitivity adjustment. Internally selectable 80 Hz highpass filters for each channel offer protection against over excursion of small bookshelf speakers and saturation of distribution transformers at low frequencies. These filters are shipped in the “off” position from the factory.
Built to be driven hard
The MA3 Amplifier drives all three channels at the continuous average rated power, indefinitely. It is specifically designed to operate in demanding commercial applications. Very low emissions allow the amplifier to operate in close proximity to signal processing equipment without causing excessive interference. The CP52S
, CP64S, CP66
may all operate next to the MA3 in a rack. The high efficiency “heat tunnel” design allows the amplifier to process severely compressed signals reliably even when installed in a rack with elevated ambient temperatures. Forced-air cooling keeps heat away from other equipment.
You won't hear the other Zones
The MA3 is designed to deliver foreground music, background music and paging signals to three different Zones without annoying crosstalk. A quiet office, for example, with a paging signal only, will not hear foreground music playing in the lounge. The high capacity linear power supply incorporates three independent secondary supplies with independent bridge rectifiers and filters. The result is exceptionally good crosstalk figures even with multiple channels driving full power into 4Ω loads.
No bad “spikes”
The MA3 is designed to operate without interruption of signal with as little as 85 VAC available (120 VAC unit). Even if the Amplifier is operating at full power, the signal will not breakup as the AC line voltage drops to 85 VAC. If the AC line drops lower than 85 VAC the signal mutes without “spikes.” Once AC power is restored, the signal restarts quickly without “spikes” or signal breakup.
The good “SPiKe”
The power amplifiers in the MA3 are protected with National Semiconductors’ proprietary SPiKe* protection circuitry. SPiKe protection offers a level of protection not available in conventional amplifiers. It has the ability to instantaneously monitor the temperature of the power device die, yielding a level of reliability not achievable with discrete designs.
It’s OK to light the 0 dB Headroom indicator a lot
The high-performance limiter used in the MA3 means all the available power can be delivered to the load and not simply held in reserve to avoid overload. There is no need to buy up to four times the required power just to prevent occasional system overload. The MA3 can compress a signal with 9 dB of dynamic power range down to a signal with 3 dB of dynamic power without loss of speech intelligibility or excessive distortion. With typical amplifiers, when 40 watts is needed to achieve a required average SPL of 80 dB, the contractor must buy an amplifier rated at no less than 160 watts just to maintain 6 dB of headroom. The figure below illustrates the performance of the MA3 limiter.
*Spike is a registered trademark of National Semiconductor Corporation.
SPiKe is an acronym for Self Peak Instantaneous (Ke) protection circuitry.