Realistic Optimus-21 Speakers, Pair — Walnut, Serviced, Japan

A pair of Realistic Optimus-21s, fully gone through, in their original oiled walnut veneer.

What they are

Radio Shack sold an enormous amount of forgettable gear under the Realistic name, and then occasionally sold something like this. The Optimus-21 was custom manufactured in Japan for Radio Shack, and the build quality tells you which of those two categories it belongs in: real oiled walnut veneer over a sealed cabinet, three drivers, and a rear panel with controls most speakers at any price never offered.

It was only in the catalogue for two years, at the end of the seventies, which is part of why they are not a common sight.

The cabinet is a proper acoustic-suspension design — completely sealed and packed with fibreglass, the same principle Advent and AR built their reputations on. Sealed boxes trade a little efficiency for bass that stops when the note stops, rather than the loose overhang a ported box of the era would have given you. At twenty-two inches tall these are a substantial speaker, not a compact, and the numbers follow: Radio Shack rated them 45 Hz to 18 kHz within three decibels. Note the tolerance. Plenty of speakers then and now claim twenty to twenty thousand without saying how far the response wanders to get there; a maker willing to publish a window of three decibels either way is telling you something the bigger number does not.

The rear panel is the giveaway

Two switches sit on the back of each cabinet, and both are unusual at this level.

The first is marked SYSTEM LOCATION, and it selects LEFT or RIGHT. That is a speaker designed to be voiced for which side of the room it stands on, rather than an identical pair left to fend for themselves.

The second is HF COMPENSATION, with three positions: HIGH, LOW and NORMAL. It adjusts the top end to suit the room — bright walls and bare floors want one setting, heavy curtains and carpet want another. Having that choice at the speaker, rather than reaching for tone controls on the amplifier, is genuinely useful in a real listening space, and it is the sort of thing that quietly disappeared from speakers as the years went on.

What it does, in short, is steer the top end according to which side of the room the speaker stands on. Both of the small drivers stay working; the switch changes their relationship to one another so the highest frequencies are aimed in toward where you are actually sitting. It is a neat piece of thinking for a speaker sold in a high-street chain.

Connection is by a pair of screw terminals, 8 ohms, with the impedance marked on the plate.

The work that has been done

These have been properly serviced rather than dusted off.

The woofer surrounds have been replaced. That matters more than anything else on a speaker of this age, because the original foam perishes on every example eventually, and a pair still wearing its factory surrounds is a pair with a bill attached to it.

The tweeters have been serviced.

The grille cloth is new, cut and fitted here.

Condition

Very Good, with one honest exception: there is a significant chip in the veneer on one cabinet. It is named here rather than discovered later, and it is the reason these are priced where they are. Everything else presents well — the finish is the original factory veneer, a warm orange-tan that has aged into itself, and from a normal listening distance the pair looks the part.

A well-built Japanese speaker wearing a Radio Shack badge, serviced where it matters, and priced for the mark it carries rather than in spite of it.

Available for pickup in Kanata, or shipped across Canada and internationally — we have sent equipment to fifteen countries in the past year, each piece packed in-house in 275 lb test double-wall boxes. Live shipping rates for your address are calculated at checkout. Backed by Radique Audio’s Bumper-to-Bumper Warranty and our Perpetual Trade-Back Program. Available for audition by appointment in Kanata.

Realistic Optimus-21 Specifications

• Realistic Optimus-21, Catalogue No. 40-2026
• Custom manufactured in Japan for Radio Shack, a division of Tandy Corporation
• Nominal impedance: 8 ohms
• SYSTEM LOCATION switch: left / right
• HF COMPENSATION switch: high / low / normal
• Connections: screw terminals
• Two-way, three-driver acoustic-suspension design, sealed and fibreglass filled
• Frequency response: 45 Hz to 18,000 Hz, plus or minus 3 dB
• One woofer and two 3-inch cone drivers per cabinet
• Power handling: 70 watts
• Finish: original oiled walnut veneer
• Dimensions: (Width x Height x Depth) 12.4 x 22.3 x 11.0 inches (314 x 565 x 279 mm)
• Weight: 25.4 lbs (11.5 kg) each

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