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This US$39 asking price is ambitious for a used Optimus SA-155, sitting well above the median US$30 and exceeding the 75th percentile US$33 from your 26 comparable listings; it’s roughly US$9 over the median and US$6 above the top quartile. While comparable listings on Etsy show prices around US$105 for tested working units, those appear to be outliers or include significant extras, whereas your database anchor of US$30 median better reflects the typical used market for this budget-era Radio Shack amplifier.
The Optimus SA-155 is a solid entry-level integrated amplifier that delivers 6 watts per channel, enough for small speakers or desktop setups, and is valued for its simple, reliable design and compact form. If this listing includes original cables, a clean condition, or is from an original owner, that adds modest upside, but at US$39, you’re paying a premium without clear justification. For a fair deal, wait for something closer to US$30–US$33; only consider this if the condition is exceptional and accessories are included.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Optimus is best known as a RadioShack private-label audio brand rather than an independent hi-fi manufacturer. The name traces back to RadioShack’s in-house branding, with “Optimus” used on some products from the late 1960s and more broadly on audio gear in the 1980s and 1990s. It does not have a clearly identifiable standalone founder in the way a dedicated hi-fi brand would; its heritage is tied to the RadioShack retail chain in the United States.
The line covered a broad range of consumer electronics, including stereo receivers, amplifiers, speakers, cassette decks, turntables, and later some home-theater and portable audio products. Depending on the era, many Optimus components were sourced from overseas OEM manufacturers, especially in Asia, and sold through RadioShack’s stores as house-brand alternatives to mainstream consumer audio lines.
In the market, Optimus sits firmly in the mass-market and mid-fi category rather than the high-end segment. Today it is mostly remembered by vintage-audio collectors and RadioShack enthusiasts, with certain receivers and speakers drawing interest for their retro appeal and occasional value. It is not generally regarded as a boutique or audiophile-first brand, but some models remain noteworthy for solid build and nostalgic charm.
See all Optimus listings on RADAR.
