Sherwood S-5500 (c. 1961)
Fifteen controls, twelve inputs, and a price forty dollars under the flagship. The S-5500 was Sherwood's stereo amplifier for listeners who didn't need the top of the line.
Overview
By 1961 Sherwood's Chicago operation knew how to build a stereo amplifier, and the S-5500 shows it. It is a 60-watt stereo amplifier, 25 watts music power per channel, and the company placed it just below its own S-5000 II. Sherwood's advertising states the relationship plainly: the S-5500 is the same as the S-5000 II except for 50 watts music power and no presence rise, at $159.50 against the S-5000 II's $199.50. That forty-dollar gap got the buyer the same circuit topology minus a midrange contour control and some output headroom. For a lot of buyers in 1961, that was the sensible trade.
The front panel has fifteen controls and switches and twelve inputs. Sherwood didn't strip the feature set to hit the lower price. The rumble and scratch filters, the tape monitoring and the phase-reverse switch all stayed. The filter spec is unusual for the era: 12 dB per octave, effective at all inputs rather than just the phono stage. A lot of period amplifiers filtered the turntable input and nothing else, which left tape and tuner sources exposed to whatever rumble or noise came down the line. Sherwood wired the filters across the board.
The tone controls are another period oddity. Bass and treble are friction-locked, and they can be adjusted per channel or ganged for both channels at once. Much of the competition used fixed dual-concentric controls. On the S-5500 a channel imbalance can be corrected at the tone stage instead of at the balance control, which helps when a room or a speaker placement is fighting the listener.
The Numbers, and What They Mean
Sherwood rated the S-5500's hum and noise at 80 dB below 24 watts on the radio input and 60 dB below 24 watts on phono. Look at that second figure. Twenty decibels of difference between line and phono is a lot. The high-level inputs are quiet, and the phono stage is a conventional tube-era design that will hiss a little when the gain is pushed. That's what 1961 phono stages did, and it's no knock on Sherwood in particular. A modern buyer running a high-output cartridge should expect some noise floor on the phono input, while line-level sources will be almost silent.
Frequency response is specified as plus or minus one dB from 20 to 40,000 cycles. That's a wide, flat window for the period. The ±1 dB tolerance across four octaves says more about the middle of the band than the extremes: the amplifier isn't shaping the signal in any audible way. Intermodulation distortion is 1.5 percent at 24 watts continuous, and harmonic distortion is 0.5 percent at the same output. Those are honest mid-century tube numbers. They are not low by later solid-state standards, so nobody should buy an S-5500 expecting modern measured performance.
Damping factor is five. Sherwood's own copy says this "assures optimum performance with today's low-efficiency speaker systems," and that claim needs a raised eyebrow. A damping factor of five is low even by 1961 standards. The output impedance is high enough that the amplifier will interact audibly with speaker impedance curves. An S-5500 driving a speaker with a bumpy impedance curve will give a slightly different tonal balance than the same amplifier driving a flat one. That isn't a defect to fix. It is how the design behaves, and some listeners of tube amplifiers from this era like what that interaction does.
Recording Flexibility and System Integration
Sherwood built the S-5500 for people who used their tape decks. Two cathode follower outputs feed a front-panel tape monitoring switch, and Sherwood's literature says the combination gives "complete recording flexibility" for home or professional-type stereo tape recording. Cathode followers were a deliberate choice. They present a low impedance to the tape deck, so long cables and unfussy recorder input stages won't degrade the signal. Anyone who has fought hum and rolloff on a tape send will see the point.
Twelve inputs across the rear panel and front selector make the S-5500 a workable control center for a complex system. Alongside the tape loop there is a stereo-reverse switch and a phase-reverse switch, the kind of utility features that vanish from later, cheaper gear. Phase reverse is useful for diagnosing out-of-phase recordings and for correcting speaker wiring without crawling behind the cabinet.
The loudness control has its own in/out switch instead of being tied to the volume pot. That lets the listener defeat the loudness compensation independently, engaging it at low levels and disengaging it at realistic ones without touching the volume setting. Individual gain controls sit alongside the stereo balance control, so channel levels can be trimmed at the source rather than only at the output.
Historical Context
Sherwood Electronic Laboratories operated out of 4300 North California Avenue in Chicago, and by the early 1960s the company was placing full-page advertisements in the major audio monthlies. A 1962 campaign in High-Fidelity (March 1962, p.124) ran the tagline "only for those who want the ultimate" above the S-8000 FM/MX stereo receiver and the S-3000 tuner. Those were the S-5500's stablemates in a lineup of tuners, amplifiers, and receivers. The same push, in High-Fidelity (July 1962, p.100), described the S-8000 as combining a stereo tuner, two 32-watt amplifiers, and two phono/tape preamplifiers in one chassis at $299.00. The S-5500 sat below that flagship as a separates component for listeners assembling a system piece by piece.
By the early 1960s the company was calling itself "the fastest-growing manufacturer of Stereo High Fidelity components in the United States," and it exhibited at the International Audio Festival & Fair with a demonstration room alongside its booth. That's marketing copy, not an independent assessment, but it shows the scale Sherwood was working at during the S-5500's window. The amplifier was part of a broad catalog that also included the S-2000 II FM/AM tuner at $145.00, the S-1000 II "Music Center" amplifier-preamplifier at $109.50, and modular component furniture in hand-rubbed walnut. Sherwood was selling a whole system, not just a box.
The S-5500's production span isn't documented in the surviving material. Period advertisements and listings place it firmly in the early 1960s. A classified advertisement in a 1961 issue of Audio magazine offered an unopened S-5500 dual 24-24 watt stereo amplifier, with or without cover, for $134.00. That is a discount against the $159.50 list price, which suggests dealers were moving stock. The same issue of Audio carried the new-product announcement describing the S-5500 as a 60-watt stereo amplifier with fifteen front-panel controls and twelve inputs at $159.50 less case. Buyers who wanted the walnut cabinet paid extra for it. The base price bought the chassis alone.
Collectibility and Value
The S-5500 sits in an awkward spot in the collector market, and the model number is the reason. Sherwood reused and extended the S-5500 designation across multiple products, and various bundles with S-3000 series tuners carry badges that read like this amplifier's descendants. A search for "Sherwood S-5500" will turn up tube-era integrated amplifiers, later solid-state gear, and tuner combinations that have nothing to do with the 1961 stereo amplifier described here. Verify the actual chassis and the control layout before committing money. The badge alone is not enough.
For the unit itself, value tracks condition and completeness. The original $159.50 price, a serious commitment in 1961 dollars, has not turned into a premium on the secondary market. The S-5500 does not command the prices that Marantz and McIntosh tube gear of the same era routinely fetch. A buyer who wants 1961 American tube amplification with a full feature set can find it here for a fraction of what the prestige brands cost.
Maintenance is the standard tube-era list. The electrolytic capacitors in the power supply are the first failure point on any amplifier of this age, and a unit that hasn't been serviced will likely hum. The friction-locked tone controls and the multi-position selector switches are mechanical assemblies that collect oxidation and benefit from cleaning. Output tubes, if the unit still has its originals, are almost certainly at end of life. None of this is unusual or disqualifying. It comes with any 1961 tube amplifier, and the S-5500's relatively simple circuit makes it a reasonable restoration candidate for a technician who knows the period.
The case counts as a separate line item. The S-5500 was sold at $159.50 less case, and Sherwood offered modular component furniture in hand-rubbed walnut as an accessory. A surviving unit with its original cabinet is meaningfully more desirable than a bare chassis, and a unit with the factory box and documentation more so. The amplifier was often installed in custom cabinetry, and the period advertising shows room-divider and wall-type decorator units built to house hi-fi components. Many S-5500s were separated from their factory cases decades ago and will never be reunited with them.
For a modern listener the S-5500 is a 1961 tube stereo amplifier with a comprehensive control set, a tape loop built for real recording work, filters that function on every input, and a damping factor low enough that it will color the sound of whatever speakers it drives. It is not a transparent amplifier and never claimed to be.
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