Sony TA-1055
The cheapest amplifier Sony would sell you in 1973 — and the company was strangely proud of exactly that.
Overview
The TA-1055 was the bottom rung of Sony's 1973 amplifier ladder, and the company's own advertising leaned into it: this was the lowest-priced integrated amplifier in the line, pitched alongside the matching ST-5055 tuner as the entry point to a range that climbed all the way to separates like the 3200F power amp and 2000F preamp. High Fidelity (April 1973, p.24) ran the pitch as a two-model introduction, framing the amp and tuner as the affordable way into "traditional Sony performance and value." Whether that framing holds up half a century later is the interesting question, because the specs Sony printed are honest about what you were and weren't buying.
Start with the power claim, because it's the one number that defines this amp. Sony rated the TA-1055 at 20+20 watts RMS continuous into 8 ohms per channel, from 40 Hz to 20 kHz. That's the conservative, full-bandwidth rating — not a 1 kHz cherry-pick — and the ad copy made a point of it: the power you pay for is the power you get, at every frequency from the bottom of the bass up through the treble. Twenty watts per channel is not a lot, and nobody should pretend otherwise. But a genuine 20 watts across the whole audio band, from a direct-coupled differential output stage, will drive reasonably efficient speakers to satisfying levels without the sag and compression that plague amps whose rated power exists only at one convenient frequency. Audio (August 1973, p.9) carried the same 20+20W figure in its pages, so the number is consistent across the period press.
The supporting circuitry is where Sony spent its money. The output stage is direct-coupled and differential, and the phono section is a wide-range integrated-circuit preamp — a detail worth pausing on, because in 1973 an IC phono stage in a budget integrated was not a given, and it speaks to how Sony chose to build down to a price rather than strip the front end bare. Owners report the phono input is the reason to keep one of these around; it's quiet and it tracks a moving-magnet cartridge without fuss.
Then there's the feature set, which is genuinely odd for an entry-level amp. Sony fitted two sets of tape output and monitor connections, with direct dubbing between them — and the ad copy explicitly suggests using one of those loops for an SQ decoder, which tells you exactly what year this was and what the company expected buyers to be curious about. There are front-panel Aux and Mic inputs, so you're not reaching around the back to plug in a second source or a microphone. And the tone controls are slide controls rather than rotary knobs — a small thing that gives the front panel a distinctly early-'70s look and, more practically, lets you see at a glance where the settings sit.
The price story is messier than a single number, and collectors should know it. Early 1973 advertising — the March Audio (p.25) and April High Fidelity (p.24) placements — lists the TA-1055 at $149.50, and in that same copy the matching ST-5055 tuner is quoted at $159.50 including a walnut-finish cabinet. By the August 1973 Audio (p.9) and High Fidelity (p.31) ads, the amplifier has moved to $169.50. That's a real $20 swing within a single model year, and it's the kind of thing that makes "what did this cost new" a question with more than one right answer. Anyone quoting a single figure as gospel is picking a month, not a fact.
There is also a power-rating discrepancy buried in the ad campaign itself that's worth flagging plainly. The earliest placement — Audio (March 1973, p.25) — claims 23+23 watts RMS into 8 ohms from 20 Hz to 20 kHz. Every later ad in the run, including Audio (August 1973, p.9) and High Fidelity (August 1973, p.31), states 20+20 watts from 40 Hz to 20 kHz. Two possibilities: Sony revised the spec downward to a more conservative, defensible figure, or the early number was optimistic copy that got corrected. Either way, the later, lower, narrower-band figure is the one that appears repeatedly across two different magazines, and it's the one to trust. Treat anything claiming 23 watts as an early-advertising artifact.
As for the matching tuner, the ST-5055's published sensitivity of 2.2 µV IHF was described in Sony's own copy as moderate by the standards of the day — an unusually candid admission in a print ad — but paired with a 1 dB capture ratio, which is genuinely good and speaks to how cleanly the tuner would lock a stereo station. It also carried a high-blend switch for pulling quiet stereo out of weak signals, built-in AFC, a signal-strength meter, and switchable muting. The tuner is a separate product and shouldn't be conflated with the amp, but the two were sold as a pair and the amp's dual tape loops were clearly designed with that kind of system-building in mind.
What the TA-1055 is, then, is a modest, honestly-rated little integrated from a company that was simultaneously building some of the more ambitious gear of the era. It is not a giant-killer and it was never meant to be. It's the amp you bought when you wanted a real Sony — differential output stage, IC phono preamp, sensible features — and had about a hundred and fifty or seventy bucks to spend. The slide controls and the dual monitor loops give it more character than its wattage suggests, and the phono section punches above the price. Twenty watts is twenty watts, though, and anyone pairing one with inefficient speakers will find the ceiling quickly.
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