{"product_id":"audio-research-foundation-ls28-line-stage-pre-amplifier","title":"Audio Research Foundation LS28  Line-Stage Pre Amplifier","description":"LS28 - Line Stage Preamplifier \u003cbr\u003e\u003cbr\u003e\n\nThe LS28 line stage is a flexible and intuitive preamplifier. Four balanced and four single-ended inputs, and two sets of both balanced and single-ended outputs, allow maximum connectivity. The straightforward menu allows control of numerous parameters, including input naming, tube hours, auto shutdown, and home theater passthrough. Phase invert and mono are also standard functions. At the heart of the LS28 are four 6H30 vacuum tubes in the analog circuit. While the LS28 is the perfect match for any Audio Research amplifier, it has been designed to work with nearly any amplifier on the market today.\u003cbr\u003e\u003cbr\u003e\n\nSince 1970, High Definition has been more than our trademark; it has been our guiding principle for all products. The Foundation Series continues this passion and philosophy, offering the listener stunning playback, great value, and unparalleled long-term support.\u003cbr\u003e\u003cbr\u003e\n\nTECHNICAL SPECIFICATION:-\u003cbr\u003e\u003cbr\u003e \n\n\nFREQUENCY RESPONSE\n+0-3dB, 0.4Hz to 200kHz at rated output (Balanced, 200k ohms load)\u003cbr\u003e\n\nTHD+NOISE\nLess than .007% at 2V RMS BAL output.\u003cbr\u003e\n\nNOISE\nLess than -100dBv at max volume (103).\u003cbr\u003e\n\nDYNAMIC RANGE\n122dB (AES17).\u003cbr\u003e\n\nCROSSTALK\n-105dB\u003cbr\u003e\n\nGAIN\nMain output: 18.7dB balanced output. (9.3dB SE output.)  Record output: 0dB (Processor input: 0dB balanced out).\u003cbr\u003e\n\nINPUT IMPEDANCE\n100K ohms Balanced, 50K ohms SE. 8 Inputs - 4 balanced, 4 single-ended.\u003cbr\u003e\n\nOUTPUT IMPEDANCE\n600 ohms Balanced, 300 ohms SE Main (2), 20K ohms minimum load and 2000pF maximum capacitance. Outputs (3): 2 Main, 1 Record (XLR and RCA connectors).\u003cbr\u003e\n\n\n\nOUTPUT POLARITY\nNon-inverting.\u003cbr\u003e\n\nMAXIMUM INPUT\n16V RMS BAL, 8V RMS SE.\u003cbr\u003e\n\nRATED OUTPUTS\n2V RMS (1V RMS SE) 1Hz to 200kHz into 200K ohm balanced load (maximum balanced output capability is 17V RMS at less than 0.5% THD at 1kHz).\u003cbr\u003e\n\nCONTROLS\nRotary volume selector (103 steps) and rotary input selector. Push buttons: Power, Menu, Enter, Mono, Invert, Mute\u003cbr\u003e\n\nPOWER SUPPLIES\nElectronically regulated low and high voltage supplies.  Automatic 45 sec. warm-up\/brown-out mute.  Line regulation better than .01%.\u003cbr\u003e\n\nTUBE COMPLEMENT\n(4) 6H30P dual triode.\u003cbr\u003e\n\nPOWER REQUIREMENTS\n105-125VAC 60Hz (200-250VAC 50\/60Hz) 130 watts maximum.\u003cbr\u003e\n\nSTANDBY\n2W","brand":"Audio Research","offers":[{"title":"Black","offer_id":57409469120844,"sku":"AUDIORFOUNDLS28-B","price":7406.67,"currency_code":"GBP","in_stock":true},{"title":"Silver","offer_id":57421008404812,"sku":"AUDIORLS28S","price":7406.67,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1053\/6891\/2204\/files\/Audio-Research-LS28.jpg?v=1777486626","url":"https:\/\/www.stoneaudio.co.uk\/products\/audio-research-foundation-ls28-line-stage-pre-amplifier","provider":"Stone Audio","version":"1.0","type":"link"}