LS28SE Line-Stage Preamplifier A high-end preamplifier in its technical performance. An instrument in its ability to deliver a realistic and emotional connection to the music. The LS28SE draws on Audio Research’s experience creating, of all things, our Reference 160-series power amplifiers. Numerous costly component upgrades elevate the LS28SE’s clarity, resolution, transient snap, and sense of space. The relaxed purity and natural sense of balance are instantly noticeable and will inspire extended listening sessions. Flexible operation The LS28SE line stage offers flexible and intuitive operation. Four balanced and four single-ended inputs, and two sets of both balanced and single-ended outputs allow maximum connectivity. Input naming, tube hours, auto shutdown, and the assignment of home theater passthrough are all easily directed through the menu. Phase invert and mono are also standard functions. The impact of a great preamplifier on your music system must not be ignored. While loudspeakers and power amplifiers are obviously critical to the sound you hear, preamplifiers are often underestimated. Musical stones lay unturned because most preamps do not stand up to the caliber of the system in which they reside. Enter LS28SE. Its organic tone and inner detail bring an instant vitality and refinement to systems formerly employing other preamplifiers. TECHNICAL SPECIFICATIONS Frequency Response +0-3dB, 0.4Hz to 200kHz at rated output (Balanced, 200k ohms load) THD+Noise Less than .007% at 2V RMS BAL output Noise Less than -100dBv at max volume (103) Dynamic Range 122dB (AES17) Crosstalk -105dB Gain Main output: 18.5dB balanced output. (12.5dB SE output.) Record output: 0dB (Processor input: 0dB balanced out). Input Impedance 100K ohms Balanced, 50K ohms SE. 8 Inputs – 4 balanced, 4 single-ended. Output Impedance 600 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). Output Polarity Non-inverting Maximum Input 16V RMS BAL, 8V RMS SE Rated Outputs 2V RMS (1V RMS SE) into 200K ohm balanced load (maximum balanced output capability is 17V RMS at less than 0.5% THD at 1kHz). Controls Rotary volume selector (103 steps) and rotary input selector. Push buttons: Power, Menu, Enter, Mono, Invert, Mute. Power Supplies Electronically regulated low and high voltage supplies. Automatic 45 sec. warm-up/brown-out mute. Line regulation better than .01%. Tube Compliment (4) 6H30P dual triode Power Requirements 105-125VAC 60Hz (200-250VAC 50/60Hz) 130 watts maximum Standby 2W Dimensions Width: 19” (48 cm) Height: 6.5” (13.7 cm) Depth: 13.7” (34.8 cm) Handles extend 1.6” (4 cm) forward of the front panel Weight: 16.0 lbs. (7.2 kg) Net; 24 lbs. (10.9 kg) Shipping
