Welcome to our website! As we have the ability to list over one million items on our website (our selection changes all of the time), it is not feasible for a company our size to record and playback the descriptions on every item on our website. However, if you are an American with a disability we are here to help you. Please call our disability services phone line at 512-454-4534 during regular business hours and one of our kind and friendly personal shoppers will help you navigate through our website, help conduct advanced searches, help you choose the item you are looking for with the specifications you are seeking, read you the specifications of any item and consult with you about the products themselves. There is no charge for the help of this personal shopper for any American with a disability. Finally, your personal shopper will explain our Privacy Policy and Terms of Service, and help you place an order if you so desire.


Parasound A31

Three-Channel Power Amplifier

Halo Collection


250 watts x 3 @ 8 Ohms / 400 watts x 3 @ 4 Ohms
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 F 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
Continuous power output:
250 watts RMS x 3, 20 Hz - 20 kHz, 8 Ω, all channels driven
400 watts RMS x 3, 20 Hz - 20 kHz, 4 Ω, all channels driven
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/ second
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
17-1/2" w x 7-5/8" h x 20" d, 7" h without feet
Net weight: 65 lb.
Shipping weight: 79 lb.

Quick Specs

  • Appearance

  • Type: Amplifier

  • Dimensions

  • Width: 17 1/4"
  • Height: 7 5/8"
  • Depth: 19 1/8"

  • Features

  • Energy Star Rated: No

Professional delivery and installation is available for every product we sell. We would be happy to coordinate delivery and installation for you.

Extended warranties are usually very inexpensive and can save you thousands in the future. It's simple and inexpensive to purchase extended warranties and one of the smartest ways to protect your investment.

Electronics can be large, heavy and expensive. You probably don't have the special tools or expertise needed to fix them in a crisis. If you can spare a few thousand dollars without batting an eyelash for new electronics should they break tomorrow, don't buy a warranty. But if you're like most of us, protect yourself by purchasing inexpensive extended warranties when you buy a new product and save yourself big money in the long run.