Amplifiers & Receivers

Mid-Fi Amplifiers & Receivers

Lafayette Electronics made two good mid-power integrated amplifiers in the early 1970s. The LA-125B and LA-950 were in the 25-40 wpc range. Kenwood made wonderful amplifiers under the Trio and Kenwood brand names. Among the very affordable models were the 13 wpc KA-2000, the KA-2002, and the KA-4002. The late 1970s KA-3500 was at the entry point to a series of high performing amps. The KA-305 was a less elegant version of the 3500 that closed out the decade but still offered nice performance and minimalist cosmetics in the 40 wpc range.

Receivers in these years were often something quite special. At the lower end, Realistic made a number of attractive models with good performance. Two of the most popular was the STA-45 and STA-47. Their successor, the STA-52 was not as well-made but still offered an attractive design with excellent performance for a 12 wpc design. Another popular Realistic receiver with classic cosmetics was the STA-64/64B with 16 wpc.

I own a relatively rare STA-76 which replaced the STA-47 in the mid-1970s. It is a lovely design, well- built with very clean and classic cosmetics. I listen to this unit daily in my office desk-top system. The STA-77 added a bit more power and fancier cosmetics. The STA-90 boasted considerably more power and seems to be one of the last Radio Shack receivers that retained a classic look and good build quality without excessive with frills and features. Not long after these models, Realistic receivers dropped the classic silver–era look in favor of the high-tech black styling and cheap construction that would come to dominate the market in the mid-1980s.

Another classic late 1970s receiver was the Technics SA-5070. It was solidly built with about 15 wpc. Technics had several receiver designs during these years that featured odd or overly cluttered cosmetics but the SA-5060 and SA-5070 kept the styling within the boundaries of “clean” and “classic.”

Another favorite of mine is the Kenwood KA-3400 which moves you into the next tier of power (20+ wpc) and offers classic silver era styling. The Kenwood KA-3600 cemented their position as a leading “bang for the buck" line. For those moving into higher budget very serious hi-fi, the Kenwood KA-9400 receiver was a worthy competitor to many of the biggest names of the period with great build quality and performance. It had a striking appearance, albeit a bit more cluttered than classic designs. A harbinger of things to come with the monster receivers of the late 80s, the KA-9400 still retained much of the cosmetic appeal that made Kenwood’s smaller receivers so popular in the mid-fi market.

KLH receivers were always something special, beginning in 1969 with the Henry Kloss designed Model Twenty Seven. Its iconic minimalist design and wonderful performance made it a true classic, highly valued to this day. KLH followed it with made-in-Japan receivers that continued to offer better than average performance and distinctive styling. My personal favorite is the Model Fifty-Two from the early 1970s. The Model Seventy-One is also an excellent choice. All these early KLH receivers always seemed to put out a lot more usable power than their modest specs would indicate.

In terms of inexpensive receivers of a later vintage, Technics was still making some very nice silver-era products with contemporary styling from 1981-1983 in the SA-200 series. These were cheapened considerably in the SA-100 series introduced around 1985. If your budget is tight and you favor their looks, these Technics models will get you the additional watts of power you require, without much in the way of additional dollars.

Pioneer receivers were extraordinarily popular in these years but I have never used these products so I don’t comment on them here. I’m certain many models were excellent values at the time and they can likely be easily and cheaply obtained in the aftermarket. A half-dozen other Japanese companies turned out good receivers and amps under a variety of brand names before cheap construction became the norm in the mid-1980s.

You will hear a lot of negative chatter about the relatively inexpensive Technics receivers and amps from the 1980s. Some models were indeed less than stellar, but others are definitely worth listening to. Their sound can indeed be a bit bright and edgy but that can be tamed with either a judicious choice of speakers or some careful setting of tone and loudness controls. The upside is that the better models have a characteristic sound that is clean, fast and really detailed. Power is well suited to most of the speakers from that period and I have always used a number of models with few reservations.

The Next Level

The Technics SU-V series of integrated amplifiers are beyond the scope of mid-fi products discussed here but for those with bigger budgets, seeking more power, they do provide some of the best values of the end of silver era period. The SU-V4, SU-V6 and SU-V7 all very fine products for a modest price. These Technics products had very worthy competition from Kenwood KA -7100, KA-7300 and KA -7500 integrated amplifiers.

By the mid-1970s Japanese manufacturers produced wonderful integrated amps that were able to compete with and sometimes better, the biggest name American high-end brands. The Sansui AU-9500 introduced in 1974-1975 boasted unusual black cosmetics, exceptional build quality and extraordinary performance. It was followed by a full range of more affordable “black beauties:” the superlative Sansui integrated amplifiers AU-517, AU-519 AU-717 and AU-919 ((1977-1981).

For those who wanted to move out of mid-fi towards this elevated level true hi-fi design, Kenwood and Technics provided an affordable path to the high power, advanced circuitry systems. They offered great performance and value with a slightly updated version of classic silver era cosmetic design. They were last of their line in terms of styling. Nikko and Sansui had gone with a high tech black style and soon the classic silver look lost its appeal. The minimalist approach to controls and cosmetics also went out of fashion by the mid-1980s.

Amplifiers We Use

The higher end systems at Bedford Vintage Hi-Fi are powered by Kenwood KA-7100, Technics SU-V6, Technics SU-V7 and Sansui AU-519 integrated amplifiers. These drive our reference speakers which include Acoustic Research 303 (updated AR-5), KLH Model Six and Dynaco A-25.

Our smaller mid-fi reference systems use a number of nice Technics designs from the early 1980s. These were all a classic silver era look with the compact sizes favored during the min-system years. They featured Technics’ wide-bandwidth “New Class A” low distortion circuitry for a sound that fast, clean and detailed.

Their entry level amplifier was the SU-C04. This 30wpc amplifier was extremely well-built and packed a lot of weight into a 12”x9”x3” chassis. The SU-C03 is a step-up from the C04 and it has become a “go-to” amplifier for us. With 40 wpc it does a nice job of driving a wide variety of small and bookshelf speakers, and it does provide switching for main and remote speaker pairs. Measure 12”x10”x4” with a lovely, clean layout. Highly recommended Aiwa also made some wonderful mini-amps but it is difficult to locate ones in working condition. The tiny SA-A10 put out a clean 10 wpc. It had a full featured big brother (still only 9”x7”x2.5”), the SA-A30, which boasted advanced circuitry and a healthy 15wpc. Some of their mini-systems used a similar mini-amplifier, the SA-A22.

We still use an SA-A30 in our small demo systems along with a Technics SA—203 Receiver. The Technics 203 is a conventional circuitry receiver from 1982 with a 19”x12” footprint that is only 3.5” in height. It puts out a clean 30 wpc and has switching for both main and remote speakers.

For more demanding speakers we also make frequent use of our KLH-Fifty Two Receiver. We do own a vintage Kloss-designed KLH Model Twenty Seven receiver but it needs an extensive refurbishment. We also like to do much critical listening with our Harman Kardon 330C receiver.

The Best Of Mid-Fi

Some of my other personal favorites were the Sherwood brand receivers made in Japan between 1971 and 1975. These ranged from 10 wpc (S-7050) to 60 wpc (S-7990A) and all were consistently rated as “best buys” by publications in those years. The styling is a classic mix of wooden cases, silver era simplicity and attractive black tuning dials. Uncluttered beauty. The S-7100 and S-7100A are great performers In the very usuable 25 wpc range, while the S-7200 at 40 wpc will drive any of our preferred speakers with ease and grace. The S-7900A topped the line and at 60 wpc it was a very serious receiver in the Mid-Fi realm.

A bit more costly and likely the best budget performers of the 1970s were the universally praised Harman Kardon 330 series receivers which were introduced in the early 1970s and sold, with ongoing modifications, right up until the 1980s. Minimalist but attractive cosmetics, solid construction and a nice warm sound. Their circuitry design featured an unusually wide bandwidth —something that made HK amplifiers stand out in the 1960s and 1970s. Not overly powerful (17 to 20 wpc) but with a wonderfully appealing sound. All the 330 models were great buys but the 330B and 330C are the gems. Many find the 330C to be one of those components that they never tire of.

Of course, once you get to the 20wpc and higher range of amplification you’ve got the necessary power and overall quality to enjoy a wide variety of truly impressive 2 and 3 way speakers. At this point mid-fi begins to enter the world of true hi-fidelity. We’ll continue our discussion of these in the SPEAKERS pages that follow.

A note to our readers: Of course, the above conversation does not claim to be a comprehensive review of the entire low-fi & mid-fi landscape. It simply reflects my personal listening experiences with the gear that I have enjoyed since I began this project in 2008.

We favor amplifiers and receivers that have the ability to run both main and remote speakers. We often find that unusual and often excellent results can be obtained by combining pairs of very different speakers in simultaneous playback. For example, we love sound of the KLH speakers (Model 14B) that were featured in their Model Fifteen and Nineteen systems (1963-1965). These speakers get a lovely balanced sound from their twin 3.5” drivers, but most contemporary listeners would find them a bit lacking on the top end. Adding a pair of small single driver speakers like the JVC SP-UX7000 or a pair of bright mini-speakers like the Realistic Minimus Seven creates a really nice full-range sound that sparkles, without taxing the amplifier.

Any pricing mentioned in these discussions is to be taken as a useful reference but they are not to be taken as actual selling prices. The prices shown on the EQUIPMENT FOR SALE pages of this website are actual selling prices but any other prices on the website are strictly for general reference and should always be updated by way of a request to us for a formal quotation.