Audio Research Ref 160M MkII Mono Power Amplifier - PAIR MSRP: $45,000Color: Black These amplifiers are in excellent condition and function flawlessly. They are consecutive serial number amplifiers and they include their original packaging, user manual, tubes (1015 hours), 20a power cords, bias adjustment tool, and cover removal tool. These are the current version (Mk II) of the Ref 160M mono blocks and come broken in with 1014 and 1015 hours on the tubes. There are a couple very minor marks on the rear corner of the tube covers as shown in the photos. These amplifiers are available with freight shipping available or for local pickup in Columbus, OH. Feel free to message me your shipping zip code for a freight quote. Do not miss the chance to own these amazing amplifiers at an incredible price. After two years in development, the new Reference 160M MkII Monoblock Power Amplifier is built like no other, looks like no other, and sounds like no other amplifier that you have ever heard - but it is unmistakably Audio Research. It features a refined audio topology with fewer and better components in the signal-path, switchable Ultralinear/Triode operation, proprietary auto-bias, output tube monitoring and protection, an advanced power meter, and much more. This array of features has never been offered before in an Audio Research amplifier. POWER OUTPUT140 watts continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1% at 140 watts, 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) 5Hz to 70kHzFREQUENCY RESPONSE(-3dB points at 1 watt) 0.5Hz to 110 kHzINPUT SENSITIVITY2.4V RMS Balanced for rated output. (25.5 dB gain into 8 ohms)INPUT IMPEDANCE300K ohms Balanced, 100K ohms Single EndedOUTPUT TAPS16 ohms, 8 ohms, 4 ohmsOUTPUT REGULATIONApproximately 0.6dB 16 ohm load to open circuitOVERALL NEGATIVE FEEDBACK14dBDAMPING FACTORApproximately 14DISTORTION-SLEW RATE13 volts/microsecondRISE TIME2.0 microsecondsHUM & NOISE-POWER SUPPLY ENERGY STORAGE-POWER REQUIREMENTS105-130VAC 60Hz (210-250VAC 50Hz) 400 watts at rated output, 700 watts maximum, 260 watts at “idle”, 1 watt of.TUBE COMPLEMENT(2 matched pair) KT150 power output, (2) 6H30 gain stageOTHEROutput polarity: Non-inverting. Balanced input pin 2+ (IEC-268).DIMENSIONSWidth 17 ¼ (43.8 cm). Height 10 (25.4 cm). Depth 18½ (47 cm). Handles extended 19 ¼ (48.9 cm).WEIGHT56 lbs. (25.5 kg) Net; 73 lbs. (33.2 kg) Shipping.Check out my other listings.Feel free to ask any questions.NOTE: These amplifiers are being offered with freight shipping available or for local pickup in Columbus, OH. They are being offered as is with no returns.

Audio Research Ref 6SE Stereo Line Stage Preamplifier MSRP: $22,500Color: SilverThis preamplifier is in excellent condition and functions flawlessly. This is one of the best preamplifiers on the market and it sounds incredible. This preamplifier shows 2029 hours on the unit. It includes the original packaging, remote, user manual, tubes, and power cord. Do not miss the chance to own this amazing preamplifier at an unbeatable price. Electronic SpecificationsFREQUENCY RESPONSE+0-3dB, 0.4Hz to 200kHz at rated output (Balanced, 200k ohms load).DISTORTIONLess than .01% at 2V RMS BAL output.GAINMain output: 12dB Balanced output, 6dB SE output. Record out: 0dB (Processor input: 0dB BALoutput).INPUT IMPEDANCE120K ohms Balanced, 60K ohms SE. Inputs: 4 balanced, 4 single-ended. Assignableprocessor passthrough.OUTPUT IMPEDANCE600 ohms Balanced, 300 ohms SE Main (2). 20K ohms minimum load and 2000pFmaximum capacitance. Outputs (3): 2 main, 1 record out (XLR and RCA connectors).OUTPUT POLARITYNon-inverting.MAXIMUM INPUT18V RMS BAL, 9V RMS SE.RATED OUTPUTS2V RMS (1V RMS SE) into 200K ohm balanced load (maximum balanced output capabilityis 70V RMS at less than 0.5% THD at 1kHz).CROSSTALK-88dB or better at 1kHz and 10 kHz.CONTROLSRotary encoders: Volume (103 steps), Select Input. Push Buttons: Power, Menu, Enter, Mono,Invert, Mute.POWER SUPPLIESElectronically regulated low and high voltage supplies. Automatic 45 sec. warm-up/brown-out mute. Line regulation better than .01%.NOISE1.7uV RMS residual IHF weighted balanced equivalent input noise with volume at 1 (109dB below 2V RMS output.)TUBE COMPLEMENT(6)-6H30P dual triodes, plus (1 each) 6550WE and 6H30P in power supply.POWER REQUIREMENTS100-135VAC 60Hz (200-250VAC 50/60Hz) 130 watts. Standby: 2 watts.DIMENSIONSWidth: 19” (48 cm)Height: 7.8” (19.8 cm)Depth: 16.5” (41.9 cm)Handles extend 1.6” (4 cm) forward of the front panel.Weight: 37.5 lbs. (17 kg) Net; 49 lbs. (22.3 kg) ShippingCheck out my other listings.Feel free to ask any questions.I ship items only to buyers with signature required on items above $750.NOTE: Returns not accepted.

Audio Research Ref 750 SE Tube Mono Power Amplifier - PAIR MSRP: $70,000 These amplifiers are in excellent condition and function flawlessly. They are consecutive serial number amplifiers and they include their original packaging, user manual, tubes (0.2 hours), and 20a power cords. These are hailed as some of the best tube amplifiers in the world and they rarely come up for sale. This pair has ultra low hours (0.2 total hours) on them and are nearly brand new. These amplifiers are available with freight shipping available or for local pickup in Columbus, OH. Feel free to message me your shipping zip code for a freight quote. Do not miss the chance to own these amazing amplifiers at an incredible price. Listening to Reference 750 SE monoblocks in a high performance system is a transformative experience; under total control, speakers disappear from the listening room and the listener is transported into a three-dimensional realm where music takes on a palpable, tangible form. Details from source material are resolved against a black background, painting images in space with vivid reality. Bass becomes the foundation on which this living performance develops, produced with startling temporal and timbral accuracy. Here is the breath of the performer, the pick against the string, the brilliance of a full orchestra. The Reference 750 SE is prepared to deliver 750 watts of power into speaker loads of 4, 8 and 16 ohms. This is achieved by the use of a massive, custom- built power transformer delivering current from sixteen KT150 vacuum tubes. Thanks to extensive testing and strict selection of tubes, the amplifier requires little maintenance and obviates the need for costly and sonically deleterious automatic bias systems. Power supply regulation is also achieved by 6550WE and 6H30 vacuum tubes. Tube bias is controlled by two KT150 tubes, each driving a bank of eight tubes.POWER OUTPUT750 watts per channel continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 0.5% at 750 watts, below .04% at 1 watt. Approximate actual power available at “clipping” 850 watts (1kHz). (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 very critical.)POWER BANDWIDTH(-3dB points) 15Hz to 150kHzFREQUENCY RESPONSE(-3dB points at 1 watt) 1 Hz to 200 kHzINPUT SENSITIVITY4.6V RMS Balanced for rated output. (24 dB gain into 8 ohms.)INPUT IMPEDANCE200K ohms BalancedOUTPUT TAPS4, 8, 16 ohmsOUTPUT REGULATIONApproximately 0.5dB 16 ohm load to open circuitOVERALL NEGATIVE FEEDBACK13dBDAMPING FACTORApproximately 17DISTORTION-SLEW RATE20V/µsRISE TIME1.5 µsHUM & NOISELess than 0.2mV RMS – 110dB below rated output (IHF-A weighted, input shorted, 16 ohm output).POWER SUPPLY ENERGY STORAGEApproximately 1300 joulesPOWER REQUIREMENTS105-130VAC 60Hz (260-750VAC 50Hz) 2100 watts at rated output, 2400 watts maximum, 800 watts at “idle”.TUBE COMPLEMENTREFERENCE 750: (8 matched pairs) KT120 power output, (1) 6550WE regulator, (1) 6H30 regulator amplifier, (1 matched pair) KT120 driver, (1) 6H30 follower. REFERENCE 750 SE: (8 matched pairs) KT150 power output, (1) 6550WE regulator, (1) 6H30 regulator amplifier, (1 matched pair) KT150 driver, (1) 6H30 followerDIMENSIONS13½ (34.3 cm) W x 23 (58.4 cm) H x 20.8 (52.8 cm) D. Handles extend 1½ (3.8 cm) forward and rearward.WEIGHT170 lbs. (77.2 kg) Net; 395 lbs. (180 kg) per pair shipped weightCheck out my other listings.Feel free to ask any questions.NOTE: These amplifiers are being offered with freight shipping available or for local pickup in Columbus, OH. They are being offered as is with no returns.