SP-17L

About the SP-17L

The Audio Research SP-17L is a line-only vacuum tube preamplifier variant of the SP-17, omitting the phono stage to focus on line-level inputs. It features low-noise JFET inputs and uses 6H30 tubes in each section for high performance and long life. The SP-17L employs a high-voltage regulator and a 103-step volume control for fine volume adjustment, especially at low levels. It delivers a bandwidth from below 0.3Hz to above 120kHz, with an output impedance of 210 ohms single-ended, capable of driving long cables and low impedance amplifiers. The gain in the line section is approximately 11.1dB, slightly reduced from the SP-16 model, and the design emphasizes low distortion, low noise, and improved articulation, image focus, bass control, and dynamics. It includes direct access codes and discrete On-Off commands for integration with master controllers. The SP-17L is pure Class-A and is known for its quiet operation, allowing music to stand out against a black background. Dimensions are approximately 19" W x 5.2" H x 10" D, weighing 5.7 kg. It has multiple line inputs (CD, tuner, video, aux, processor) with single-ended RCA connectors and no phono input. The product was