Audio Research · SP-series tube preamplifiers

SP-5

The SP-5 is the compact ARC preamp of the late 1970s - a full tube line and phono stage in a 7.3 kg chassis.

Catalogue code: SP-5
Years: 1978–1980
Type: preamplifier (tube)
Valves & speakers: Rated output 5 V, max 60 V, tube rectified
Lifecycle: retired
Confidence: High

Specifications

Channels: 2
Technology: solid-state
Class_of_operation: A (line stage)
Weight: 7.3 kg
Original_list_usd: $595 (rose to $1,095)

Safety

Valve equipment: 400-500 V is present on the plates and stored in the supply after switch-off. ARC units are valve-matched at the factory - replacement sets must be bought as matched quads/pairs.

01 / Witnesses

What applies here

Marks that can be entered for this maker: Model / catalogue number, Model / catalogue number, British capacitor code (Hunts, Mullard), Japanese capacitor code (Nichicon, Chemi-Con, ELNA), EIA component code.

02 / Bounds

The model year is a floor

Nothing predates 1978; components only push the date later.

03 / Value

What moves the price

Sold-listing reading: fair $650, good $650, excellent $650 USD · 1 sold listings (thin sample — indicative only) · as of 2026-10-17. Asking prices only - these are live listings, not completed sales. 1 listing(s) in USD observed on 2026-10-17 via the HiFi Shark marketplace aggregator; with fewer than three observations the same min/median/max is recorded as an estimate, not as an asking aggregate, which is a reading of the ask spread, not a condition grading.