Pioneer SX-1050 Vintage Audio Review. If Apple designed a stereo receiver in the 1970s — this would be it.
The vintage audio hobby requires a dogged resolve when searching for a rare audio gem like the Pioneer SX-1050, and an even stronger back, if you’re lucky enough to find one. While the Pioneer SX-1250 is considered one of the most sought after of 70’s receivers, its “little” brother the SX-1050 is nearly the same physical size — built like a tank, and spoiler, it sounds fantastic.
You’re going to need a bigger rack
If you’re looking for a receiver that makes a statement in your listening room — you’ve come to the right place. The SX-1050 weighs in at just over 50 lbs., thirteen pounds shy of the SX-1250. The SX-1050 is virtually the same physical dimensions as the SX-1250. The SX-1250 is only 1.2 inches wider, half an inch taller and deeper than the SX-1050. Put simply, both are massive, and both need considerable thought about placement in your listening room. The SX-1050 can only fit on the top shelf of the largest audio rack we own — which can become problematic if you plan on connecting a turntable, because turntables normally command the top shelf.
To provide perspective on the size of this beast, we’ll compare it to some other classic receivers. The Marantz 2275, wrapped in its WC-22 walnut cabinet is a beefy looking receiver, however place it alongside a Sansui 9090, and suddenly the Marantz looks petite. Now, place the Pioneer SX-1050 next to the Sansui 9090 — the Sansui now looks modest in comparison. While the Sansui 9090 is taller, and the black and silver faceplate give it some extra aesthetic bulk — viewed from the side or the top, the Pioneer SX-1050 looks considerably larger and weightier.
Defining vintage audio quality — inside out
Build quality and all materials; internal structure, dials, switches and wood cabinet are topnotch. There was no compromises or cost cutting when manufacturing the SX-50 series receivers — they are over-the-top in build quality. The toroidal transformer is massive — these transformers were reserved for the top two SX-1250 and SX-1050 receiver models. Switches have a satisfying and audible “thunk” when activated, push buttons are firm when engaged, selector knobs click firmly between selections, the tuner dial spins effortlessly and smoothly. Finally, the Alps volume control with soft audible clicks as you raise and lower the volume adds a powerful and solid feeling that add extra “authority” to the overall user experience.
Design — Complex, but beautiful
Fans of architectural design will be familiar with Robert Venturi’s tome, Complexity and contradiction in architecture. A core principal of Venturi is; complex design that creates visual imbalance and stress, is more engaging and fulfilling. Complexity and contradiction define the chaotic beauty of the Pioneer SX-1050 receiver. I also believe the SX-1050 trumps the SX-1250 from an industrial design perspective. Here’s why.
The Pioneer SX-50 series evolved to full silver faceplate designs in 1976, which preceded the Marantz 22XXB pivot to a “modern” full silver face design aesthetic. The faceplate design of the Pioneer SX-1050, although complex, overall is very smooth and fluid, with very little color contrast in materials or lighting, particularly when compared to Marantz 22xx and 22xxB or the Sansui 9090, 8080 series of the same era.
Dials and switches are extraordinarily high quality beautifully machined, in fact they are best of breed for vintage audio in the 1970’s — far better than Marantz 22XX or 22XXB, and a step up from the Sansui 9090. While Marantz 22XX and 22XXB models use a balanced approach across the faceplate with uniformity of size for buttons, selector switches and knobs, the Pioneer SX-1050 follows a more chaotic approach, somewhat like the Sansui 9090 — however the complex and brutish faceplate design of the Sansui 9090 doesn’t include the thoughtful touches that tie the collective design together.
Consider for example, the position of the larger tuner control directly over the smaller volume control on SX-1050 and how it creates a design tension on the faceplate. Then note the row of identical size selector and filter buttons that run across the faceplate just under the AM/FM tuner dial. There was a clear design decision to align the mic and headphone inputs with the selector and filter buttons — as they are all the same diameter, this reduces some of the visual tension of the industrial design. Compare the Marantz 2275 faceplate design, which was sold in the same years, 1976/77, the Marantz 2275 design aesthetic of uniform size knobs clearly creates a more balanced harmony — but less engaging.
Now consider the tuner dial. While the AM/FM tuner dial (face of tuner) on the Marantz 2275 and Sansui 9090 have a layered depth, neither can compete with the dramatic rake angle of the tuner dial of the Pioneer SX-1050. The Pioneer industrial designers compensated for the visual weight of the large tuner control dial by purposely placing the tuner signal and tuning meters off-center. A less thoughtful industrial designer would have placed the meters dead center — eliminating the complexity of the industrial design, but, making it less engaging.
The muted smooth lighting of the Pioneer SX-1050 is one of the key design strategies to tie this complex and contradicted design together. If the Pioneer designers were coerced into introducing a “Marantz blue” or “Sansui greenish/blue” AM/FM tuner dial lighting to this receiver it would have overwhelmed the design. The smooth muted soft yellow lighting lets the faceplate design dominate — lighting is purely functional, not decorative. The smooth muted yellow of the signal and tuning meters match the tuner dial lighting. Finally, the input selector lights are all uniform in light orange — a fantastic design decision that reinforces the muted lighting strategy. The speaker selector lights inside the tuner dial for A, B, C all align with the speaker selector buttons in the layer below, and the same for the input lights and buttons. But note how the Stereo light on the tuner dial has a clear gap between the Speaker C light and is placed alongside the Signal meter — this is visual complexity in design.
Any Marantz 22XX or 22XXB in a Marantz Walnut cabinet (WC-22) looks stunning. We’re particularly fond of juxtaposition of Marantz modern 22XXB modern design combined with the mid-century design of the Marantz WC-22 Walnut Cabinet. While we would judge quality of the 9090 cabinet overall to be better quality — the SX-1050 is a far better design. Our key design issue with the SX-1050 cabinet is the faceplate is “framed” by two vertical wood blocks that are affixed to left and right sides of the facade. When you remove the top cover, those framing blocks stay in place. However, because the direction of the wood grain of the side and top of the wood cabinet are not flowing in the same direction, the wood blocks appear to not match. The framing blocks face and the edge grain flow vertical while the side panels of the cover flow from front to back and the top cover grain flows from the left to right. While we love complexity in design, this grain “mismatch” seems like a startling misstep. Things get worse when looking at the receiver from an elevated viewpoint. The tops of the framing side wood blocks are a very dark brown as the end grain absorbs the wood tint at a different rate than edge of face grain sides. After all of the purposeful and well thought design for these receivers — this clumsiness does not strike us a decision the designers made to add complexity, and it has always perplexed us. Note; this wood grain mismatch is found on all Pioneer SX-“50” models — including the SX-1250.
The design and quality of top ventilation grill on the cabinet bests any that we have seen on any vintage receivers. Well built, beautiful design and neat flush finish with the wood cabinet. The Marantz WC-22 Walnut Cabinet grill, or Sansui 9090 grill do not match the thought and design aesthetic of the SX “50” series grills.
The Pioneer SX-1050 cabinet sits squat — lower than both the Marantz 2275 and the Sansui which adds to the visual weight of the receiver. I’m a fan of how the Sansui 9090 has deep inset feet and greater lenghth of the receiver feet which provide the 9090 receiver a floating feeling — there is no floating sensation with the Pioneer SX-1050. It would be an interesting experiment to install slightly taller feet to test the impact on the design.
Finally, the design of the SX-1050 cabinet is without a question better than the SX-1250. The SX-1250 is an awkward mix of mid-century modern upfront and hard industrial design in the back. There is a Frankenstein feeling to the Pioneer SX-1250, while it certainly is designed from a perspective of “form following function” — considering the size of these receivers and the dominant position they hold in a room, the SX-1250 fails from a cabinet design perspective.
The sound you’ve been searching for
We ran our tests with our favorite speakers — vintage Mordaunt Short Signifer from 1979 — large three-way speakers, with 12” bass drivers — you can feel the air move in the room, even at low volume. Input devices included a vintage Thorens TD 125 MkII with a Shure V15 type IV cartridge and a BlueSound Node 2i DAC. As well as Fosi Audio phono pre-amp.
Delivering on promise and decades of reputation capital — the vintage Pioneer SX-1050 impresses sonically across the board. Great soundstage and instrument separation, powerful tight snapping bass, clear musical detailed mids that remind us of one our favorite vintage amps — the Pioneer SA-9500. There is no vintage stereo that we’ve owned that could match the quality of guitar reproduction of the Pioneer SA-9500, until now — the Pioneer SX-1050 now reigns supreme. The Pioneer SX-1050 adds a layer of lushness and detail to guitar playing that is engaging — you hear the fingers run across the frets — it feels like you’re in the room with the musicians. Fans of classical guitar, (some of our favorites; Paco de Lucia, Baden Powell, José González) or bass guitar/stand-up bass… somehow, someway find a Pioneer SX-1050, or SA-9500, SA-9900 now — you will not regret it.
The Pioneer SX-1050 strikes a delicate balance between the warm sound vintage fans love, yet with more precision and detail than you will find in the Marantz 2275/2270. It doesn’t match the velvety smoothness of the Sansui 9090 — but it matches the Sansui 9090 snappy and thumping bass — which almost no other vintage units that have crossed our threshold have been able to do.
While the Pioneer SX-1050 leans more on the cleaner side of vintage warm with accentuated highs — it is not a fatiguing sound. While our Sansui 9090 has been our main stage player for more than twelve months, with new vintage receiver and amplifier contenders arriving on a monthly basis — it has held its prime position against all competitors — but we’re now sitting on the fence. The Pioneer SX-1050 is opening a window to new sounds in our music — we’re noticing new details that we haven’t heard before, it’s damn addictive.
Across the board music of all genres played from our BlueSound Node 2i DAC through the AUX input sounded spectacular. We’ve had some in spec 70’s receivers where DAC input was mediocre at best — but in the Pioneer SX-1050, it is just perfect.
We ‘ve read multiple vintage audio posts about how the Phono Pre-amp in the SX-1250 and SX-1050 were considered only adequate — but not great. Running side by side phono tests with our Thorens TD 125 Mkii, on a Sansui 9090 — then switching over to the Pioneer SX-1050, the difference was quite startling — the Sansui Phono was substantially better. The Sansui bested the DAC in most cases playing phono — or was as good as the DAC on some recordings, but the Pioneer could not match the Sansui Phono sound. Any music played from the DAC on the SX-1050 sounded far superior to music played through the Phono input via our Thorens. Yes, we tried BOTH Phono inputs on the SX-1050, and yes, the Phono preamp is in spec.
We decided to use the Tape input and add a budget Fosi Audio Phono Pre-amp, which resulted in the magical sound we hoped for. Turntable sound through the pre-amp was stunning –, matching the Sansui 9090. Oddly enough, in our experiments, the Fosi pre-amp on the Sansui diminished sound quality… but that is another story.
The Pioneer SX-1050 will delight you in every way you hoped for. It is the pinnacle of vintage receiver design; it sounds stunning and is built to last for one hundred more years — actually two hundred years. As this stereo becomes a cherished family heirloom passed on from generation to generation, your great, great, great grandchildren will be thankful for your dogged perseverance in bagging this rare and beautiful beast.
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Copyright 2020 Mark Scott, HiFisetup
