The Parasound HALO A31 multichannel amplifier is a power amplifier that draws directly from the hefty lineage of the 5 channel A51. Like it's bigger brother - the it's also a THX Ultra 2 certified product, but the interesting backdrop to the A 31 is that it was designed in response to increasing demand for a three channel power amp that holds nothing back in power or performance. So the A 31 is identical in performance and sound to the award winning Halo A 51.
So why do you ask did Parasound see the need for this interesting proposition?
Here are a few of the many applications for the A 31:
1) To power the front three channels of a home theatre. The surround or back channels can then be powered by a smaller 2ch Parasound power amp such as the Halo A 23. This gives the greatest power to the front channels where it is needed the most.
2) To power the centre channel and two surround channels. This allows the Left and Right front speakers to be powered by a dedicated two channel power amp such as the Halo A 21, or better yet, two JC 1 monoblocks. This is ideal for the music lover who is unwilling to compromise stereo reproduction.
3) To power the front three channels in an AV receiver‐based system. The remaining surround and back channels can be driven by the receiver. This assures you the best sound for the front channels while enabling the AVR to produce more power for the surround and back channels. However you employ the A 31, you will be delighted by its impeccable sonics, striking authority and faithful reproduction of the smallest details.
So the A31 is a perfect reflection again of Parasound's commitment to ensuring the best performance at many different price-points - but also a nod to real world thinking and applications without compromising 'relative' performance in the context of smaller systems or applications.
As the A31 can output between 250watts to 400watts per channel - this is a real world measurement as this is whilst all channels are being driven (20 Hz - 20 kHz - 60 amperes peak per channel). This high power and high current output performance delivers very flexible dynamic 'headroom', which is why the amplifier can be sublimely subtle when required, and unflinchingly severe when raw power is needed. Plus, remember that like the A51, the A31 also has a high bias class A/AB operation working in tandem with it's directly coupled design (there are no capacitors or inductors in signal path). The A31's high power and high current output performance delivers very flexible dynamic 'headroom', which is why the amplifier can be sublimely subtle when required, and unflinchingly severe when raw power is needed.
As you would expect the build quality and components used in the A51 are pretty much second to none. The custom installation pedigree is also observed with an included rack mounting adapter for when it is desired not to be seen, but brilliantly heard. Befitting of it's high end custom installation pedigree the A31 also features auto turn on and a reliably solid 12v trigger for integration with processors, pre-amps or control systems. For those also wanting to tweak their THX certified installations the A31 features adjustable gain pots for up to +6db over THX Reference level.
Finally, the A31 features both balanced and unbalanced inputs (RCA's are gold plated) with a designated ground lift switch, and these high quality inputs are matched with heavy-duty 24k gold-plated 5-way speaker terminals on the output stage.
The Parasound Halo A31 is available in black and silver finishes - please specify on order.
Parasound Halo A31 Multi-Channel Amplifier Features & Benefits:
Adjustable gain for up to +6db over THX Reference level
Unbalanced RCA and balanced XLR inputs
Circuitry designed by legendary John Curl
High bias class A/AB operation
Direct coupled (no capacitors or inductors in signal path)
Complementary MOSFET driver stage and JFET input stage
24 beta-matched 15 amp, 60 MHz bipolar output transistors
1.5 kVA encapsulated toroid power transformer with independent secondary windings for each channel
98,400 µF power supply filter capacitance
DC Servo and relay protection circuits
AC present, channel status, high temperature indicators
Heavy-duty 24k gold-plated 5-way speaker terminals
THX Ultra2 certified
Auto turn-on by 12v trigger or audio signal
4u Chassis, carry handles, rack mounting adapter included
Parasound Halo A31 Multi-Channel Amplifier Specifications:
250 watts RMS x 3, 20 Hz - 20 kHz @ 8 Ω
400 watts RMS x 3, 20 Hz - 20 kHz @ 4 Ω
Current capacity: 60 amperes peak per channel
Power bandwidth: 5 Hz - 100 kHz, +0/-3 dB at 1 watt
Total harmonic distortion: < 0.2 % at full power
IM distortion (balanced 16 V rms): < 0.04 %
Slew rate: > 130 V/µsecond
Dynamic headroom: > 1.5 dB
Interchannel crosstalk: > 78 dB at 1 kHz; > 63 dB at 20 kHz
Input sensitivity: 1 V for 28.28 V (THX Reference)
Input impedance: 47 k Ω unbalanced; 94 k Ω balanced
S/N ratio: 112 dB, input shorted, IHF A-weighted
Damping factor: > 1100 at 20 Hz
Standby: 1 Watt
Maximum: 1800 Watts
Width: 171⁄2" (445 mm)
Panel height: 7" (178 mm)
Height with feet: 7 5⁄8" (194 mm)
Depth: 19 1/8" (485 mm)
Net Weight: 65 lb. (29.5 kg)