Teac A-2340SX (1976–1981)

A 48.5-pound four-channel open-reel deck that Teac's own service literature calls the direct descendant of one of the most popular four-channel machines ever sold.

Overview

The A-2340SX is what you buy when you want four-channel open-reel without stepping up to the studio-oriented A-3340S. Teac built it as a 7-inch, 4-track, 4-channel recorder. The service manual is candid about where it came from: the basic design is "highly similar" to the earlier A-2340RS, which the same literature credits as one of the most popular four-channel open-reel machines ever sold. The SX didn't reinvent that formula. It added built-in SIMUL-SYNC and a CUE lever function, and that was it. According to Analog Soundware, production ran from 1976 to 1981, but that range comes from a single source and should be treated as approximate. The service manual does confirm one date without ambiguity: the parts list has a November 1976 effective date.

This is a heavy deck. HI-Fi-Stereo-Buyers (March 1978, p.67) measured it at roughly 18⅞ × 17-5/16 × 8¾ inches and 48.5 lbs. That much transformer, motor and steel chassis is why these machines survive when lighter decks from the same era have been parted out. It also means you need a real shelf, not a wire rack. The report doesn't give the number most buyers want first, frequency response. That spec isn't documented in any source available to this archive, and neither are the input/output figures, so anyone quoting them is working from something other than the record.

Know where the A-2340SX sits in the lineup before you buy one. It is not the A-3340S. The 3340S was the multitrack workhorse, and the 2340SX carried the same family of features, four-channel capability chief among them, onto the smaller 7-inch reel format. If you need 10-inch reels and the longer uninterrupted takes that come with them, this is the wrong machine. If you want four-channel recording in a package that fits a home shelf, it fits.

Key Features

The Front-Panel Switch Bank

Teac did not skimp on controls. The front panel carries switches for power, speed, 2-CH/4-CH operation, equalization, bias, per-channel record modes, source/tape monitor, and SIMUL-SYNC selection for tracks 1 through 4. It's all laid out across the face, and in 1976 there were no menus to bury it in. HI-Fi-Stereo-Buyers (March 1978, p.67) treated the arrangement as one of the deck's defining characteristics. Four-channel work on this machine means throwing switches rather than re-patching.

SIMUL-SYNC and the CUE Lever

These are the two features that separate the SX from the A-2340RS it was built on, and the service manual names them explicitly. SIMUL-SYNC is built in, not an add-on box and not a modification, so the deck can do synchronized overdubbing across its four tracks without external sync hardware. The added CUE lever is simpler. It moves the tape against the play head during high-speed winding, so you can find a spot on the tape by ear while spooling rather than stopping, playing, stopping, and hunting.

Push-Tab Transport

The transport runs on push-tab controls: record interlock, forward, rewind, fast forward, and pause. There are no solenoids to fail and no logic boards to troubleshoot, just mechanical tabs doing mechanical work. That makes the deck less luxurious to operate than a solenoid-controlled machine, and considerably easier to keep running forty years later. The record interlock tab is a safety feature that seems fussy until the day it saves a tape.

Four-Track, Four-Channel Operation

The track system is 4-track, 4-channel, switchable for stereo, monaural, and multi-channel work, running at 7-1/2 and 3-3/4 ips. Those two speeds cover the realistic range for a 7-inch reel: 7-1/2 for critical recording, 3-3/4 when you need the running time. The deck accepts 7-inch reels maximum. A remote control, the RC-129, is associated with this model according to at least one dealer listing, though it is not documented as a standard inclusion.

Historical Context

The A-2340SX belongs to Teac's A-series. Teac positioned it as the little brother to the A-3340S, with the same feature philosophy on a smaller reel format. The service manual's own framing supports that, describing the deck as carrying forward everything that made the A-2340RS a commercial success while adding SIMUL-SYNC and the CUE lever. By Teac's own account the A-2340RS was one of the most popular four-channel open-reel decks ever sold. Production reportedly ran from 1976 to 1981, which puts it in the last stretch of the open-reel era's consumer relevance, after the format's peak and before cassette and then CD closed the door. The parts list carries a November 1976 effective date, consistent with that timeline.

Collectibility & Value

The market for A-2340SX decks is thin but real. Completed eBay sales over the past twelve months landed between $364 and $654, with a median of $438 across eight sales, roughly one machine moving per month. The broader range runs from a low of $249 to a high of $950, with the latest sale at $425. A used example described only as powering on was listed at $449.99, which puts an untested unit near the middle of the working range, not the bottom. Four-channel open-reel buyers are a small, motivated group rather than a broad collector base.

Maintenance starts with the capstan belt, and it's the first thing to check on any example you're considering. Replacements run around $13.95, and a full belt kit is $22.95, which is cheap insurance on a 48.5-pound machine. One owner noted that Teac itself probably still stocked the capstan belt as recently as 2011, though that's a decade-old observation and shouldn't be relied on today. Pinch rollers turn up under part number 50141751, and reel tables list around $45.00. For buyers in 50Hz markets such as New Zealand, conversion is mechanical rather than electrical: move the belt to the 50Hz section of the motor pulley and set the internal capacitor switch to 50Hz. Enthusiasts who've owned these decks describe them as well built, pretty easy to work on, and worth fixing. The dimensions and weight come from a single period report and aren't corroborated elsewhere, so treat them as close rather than exact.

Market Value

┌──────────────────────────────────────────────────────────────────────────┐
│ TEAC A-2340SX                                                   Nov 2026 │
├──────────────────────────────────────────────────────────────────────────┤
│ High      $950                                    Latest            $425 │
│ Median    $438                                    Trend                — │
│ Low       $249                                    Volume           ~1/mo │
├──────────────────────────────────────────────────────────────────────────┤
│ $1,000 ┤                                                                 │
│        │                         .                                       │
│        │                                                                 │
│   $657 ┤                                                                 │
│        │                    .                                            │
│        │                                        .                  .     │
│        │.              .                                                .│
│   $200 ┤                                          .                      │
│        ├─────────────────────────────────────────────────────────────────│
│    vol │█              █    █    █              █ █                █    █│
│        └─────────────────────────────────────────────────────────────────│
│         2026-02                      2026-05                      2026-08│
└──────────────────────────────────────────────────────────────────────────┘

eBay completed sales. Excludes accessories, parts, and non-working units. Hover points for details.