Audio Research Reference 80S Stereo Power Amplifier

Outwardly, the 80S shares the same dimensions as the 160M. A single shallow whisper fan is built into the bottom plate. Flexibility is built-in, too, with XLR and SE inputs, 4-8-16 ohm output taps, 12V input and output triggers, RS232 input, tube hour meter, switchable fan speeds, and defeatable auto-off function.

The feature set is the same as the 160S, including a proprietary auto-bias circuit that adjusts for not only tube age, but for powerline voltage swings. There is fusing of the output tubes, single-ended and balanced inputs for flexibility, switchable Triode-Pentode operation to accommodate loudspeakers and personal preference, output tube monitoring, and inclusion of an hour meter so you know how many hours are on the tubes–like an odometer for your amp. This is a tube amplifier that does not require fiddling, it is meant to be enjoyed. The built-in 12V trigger turns the 80S on or off when connected to a modern preamp with a 12V trigger. 

Like every Reference amplifier before it, the 80S is a fully-balanced differential design because it provides the highest performance and lowest distortion. A four-layer circuit board is used to provide a separate ground plane, better circuit layout, and fewer noise-inducing point-to-point connections. Music is projected against a quiet, jet-black background—like looking at the stars out in the country, removed from light pollution. It is magical and enveloping.

Built by hand, from the ground-up in our Maple Grove, Minnesota facility, this is created in service of the music, bringing it to life in every sense of the word. Listening through the 80S is a compelling experience, never a mental exercise. Set up appropriately, the 80S can fool you into feeling you are in the presence of the musical performance: The finest details are heard, with rich harmonics and full dynamic contrasts–from the smallest whisper to the largest crescendo–showcased with the ambience of the original acoustic space. Whatever your reference speakers may be, whether they are from Wilson, Magnepan, Vandersteen, Focal, Sonus faber, B&W, or whatever you like: the Reference 80S will elevate their performance to a new plateau.

Technical Specifications:

• POWER OUTPUT: 70 watts continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1% at 140 watts (33 watts in Triode mode) per channel, below 0.04% at 1 watt (Note that actual power output is dependent upon both line voltage and “condition” i.e.: if power line has high distortion, maximum power will be affected adversely, although from a listening standpoint this is not critical)
• POWER BANDWIDTH: (-3dB points) 7Hz to 68kHz
• FREQUENCY RESPONSE: (-3dB points at 1 watt) 0.7Hz to 94kHz 
• INPUT SENSITIVITY: 1.4V RMS Balanced for rated output. (25.5 dB gain into 8 ohms); 0.7V RMS SE for rated output. 
• INPUT IMPEDANCE: 300K ohms Balanced, 75K ohms Single Ended 
• OUTPUT POLARITY: Non-inverting. Balanced input pin 2+ (IEC-268) 
• OUTPUT TAPS: 16 ohms, 8 ohms, 4 ohms 
• OUTPUT REGULATION: Approximately 1.0dB 16 Ohm Load to Open Circuit (Damping factor approximately 8) 
• OVERALL NEGATIVE FEEDBACK: 15dB 
• SLEW RATE: 10 volts/microsecond 
• RISE TIME: 4.0 microseconds 
• POWER REQUIREMENTS: 105-130VAC 60Hz (210-250VAC 50Hz) 420 watts at rated output, 280 watts in Triode mode, 221 watts at “idle”, 3.6 watts off Units for Japan: 100VAC 50/60Hz 
• TUBES REQUIRED: 2 matched pair KT150 (Power output V1-V4); 2 6H30 (Gain stage V5, V6)
• DIMENSIONS: Width 18.5” (47 cm) chassis; 19.0” (48.26 cm) faceplate. Height 10.5” (26 cm) Depth 18.5” (47 cm) 
• With handles & connectors: 21” (53.3 cm)
• WEIGHT: 62 lbs. (28.2 kg) Net; 73 lbs. (32.7 kg) Shipping.

We endeavour to despatch same day for orders placed up to 2pm on available stock items (items with stock message "Usually dispatched within 24 hours"). Please remember to check with us first for a physical stock check if next day delivery is important to you. Any items with stock message "Usually dispatched within 72 hours" are items that we do not hold in stock but order in from the importer or manufacturer as soon as a customer order is received. Occasionally these may be delayed beyond 72 hours due to importer/manufacturer stock levels but we will inform you as soon as we can if this is the case.

UK ORDERS:  We despatch the bulk of our UK mainland items on a 24 hour service – Free of Charge.  Non Mainland locations - Isle of Man, Isle of Wight, the Scilly Isles, the Scottish highlands and Islands, the Channel Islands and Northern Ireland may take a day or so longer and are not Free of Charge. Smaller items are delivered using Royal Mail 24 or special delivery. Larger items are delivered using a courier service such as DPD or UPS. 

INTERNATIONAL ORDERS: We offer competitive rates which can be confirmed by email. Please just ask – we will need a full delivery address and telephone number. Smaller items are delivered using Royal Mail Small Packets Airmail with International Tracked and/or Signed depending on value of item and availability of the service. Larger International shipments are sent by insured and tracked services using UPS. If there are any delays due to specific customs regulations, etc, you will be contacted by Hifisound or by the courier with a request for any further information required. Customs duties can apply for shipments to any countries outside of the UK depending on where the product you have bought is made. Customers are responsible for all taxes and duties incurred when the items enter their country.

COLLECT IN STORE OR HOME INSTALL:At the request of the manufacturer some items cannot be supplied by mail order but you can click and buy them and then elect to collect them from our store or arrange a home install (if applicable). Applicable items clearly state that they are Collect in store or home install. Once ordered you will receive a message prompting you to contact us by phone or email to arrange for us to deliver and install or to reserve and collect from our store at your convenience, you will also be advised of the delivery time / stock availability as not all Home install / collect in store items are held in stock.