While in 1975 the Receiver War had seen no new victor rise to the top, 1976 would see the War enter a new gear and Pioneer would once again be the catalyst.
Pioneer had not been idle during the course of 1975, and while their competitors scrambled to match the SX-1010 in power, Pioneer had been slowly and deliberately designing and perfecting their next beast. In 1976 Pioneer released the legendary SX-1250. The SX-1250 Retailed for $900.USD in 1976 which today (2015) would equate to ~$3,760.00USD in 2015.
Smashing the performance of even their closest competitors in terms of RMS power the SX-1250 boasted a stunning 160 Watts RMS power per channel at 20 to 20,000Hz, Pioneer was once again top dog.
And Pioneer was not shy about it either! Their advertising material cheekily embarrassing their rivals by publishing their competitors top Receivers specs along side the SX-1250 with the tag line – “Pioneer has developed a receiver that even Marantz, Kenwood and Sansui will have to admit is the best.”
Released as their flagship product the SX-1250’s build quality and craftsmanship was astounding, virtually hand-made in their Japanese plants, no expense was spared in this units design and manufacture. Not only would this Receiver produce a whopping 160 Watts RMS per channel, it also introduced improvements throughout the entire system, the attention to detail in the design of this beast was evident on all levels, even down the the star-quad wiring implemented to reduce electromagnetically induced noise – today this same technique is now used in high-end studio microphones and boasts that it can reduce the noise from stage-lighting consoles to 1/10th that of 2-conductor cable.
The foundation of any amplifier is the power supply and the one in this unit was like nothing before seen in a Receiver. It featured a 22-pound toroidal core transformer with independent dual windings and four massive ‘Coke Can’ size 22,000uf capacitors! Toroidal transformers offer benefits of being less susceptible to power fluctuations and less likely to create noise than laminated core transformers.
As it turned out no Receiver of this period (or since?) can claim an equal to the power supply contained in the SX-1250 with it’s 88,000uf total capacitance.
The amplifier sections utilised a two-stage Class A architecture in the pre-amp and a triple-stage Darlington Direct-Coupled OCL Circuit in the Drive Stage and a Parallel Push-Pull Circuit in the Output Stage.
This design ensured a thunderous minimum 160 Watts RMS per channel at 8 ohms with only 0.1% Total Harmonic Distortion measured from 20Hz to 20,000Hz.
The SX-1250 wasn’t just a blunt instrument created simply to claim a title in raw power, it was truly revolutionary in it’s design and features – and it’s build quality was unrivalled by any Receiver before or since. It is not an overstatement to suggest that this Receiver redefined ‘top-of-the-line’. To this day the Pioneer SX series from this 1976/77 range are considered to be by many enthusiasts the best Receiver line ever manufactured by Pioneer.
As if from nowhere Technics suddenly decided they needed to pump-up-the-volume and made their debut in the Receiver Wars with the introduction of the SA-5760. This Technics Monster was rated at 165 Watts RMS per channel with only 0.08% THD, just edging over Pioneer’s SX-1250 power rating of 160 Watts.
It might not seem like much, but remember only a few short years earlier, component amplifiers had been offered by these brands with a total power equivalent of only about 5 Watts RMS per channel!
The SA-5760 power supply featured two 22,000uf caps and a laminated core transformer with dual secondaries, all to power it’s amplifier consisting of ‘Para-Push Pure-Complimentary, Direct-Coupled OCL Circuit with Single-Pack, Matched Differential Transistors.’
This item retailed at ~$799.00USD in 1977 dollars, which would equate to around $3,132.00USD in 2015 dollars. This priced it very competitively against Pioneer’s SX-1250 and the other Monster Receivers of the time. This budget/price angle was also heavily promoted in Technics literature at the time.
Tuning range: FM, MW Power output: 165 watts per channel into 8Ω (stereo) Frequency response: 20Hz to 20kHz Total harmonic distortion: 0.08% Damping factor: 60 Input sensitivity: 2.5mV (MM), 200mV (line) Signal to noise ratio: 78dB (MM), 95dB (line) Output: 200mV (line) Speaker load impedance: 4Ω to 16Ω Dimensions: 550 x 175 x 493mm Weight: 23kg
Original 1976 USD RRP: $1,100.00
Inflation Adjusted 2015 USD RRP: $4,605.00
180 Watts RMS per channel at 8 ohms with 0.1& THD from 20-20,000Hz
Rotel has operated since the late 1950s and initially manufactured products for various HiFi brands including Harman-Kardon, H.H. Scott and Marantz. It wasn’t until 1969 that the company started producing units under its own name, and in 1976 Rotel entered the Receiver War with a 180 Watt blast!
The RX-1603 is certainly a righteous Monster and Rotel showed that they were serious by topping the RMS power scales for 1976 by producing this 180 Watts RMS per channel mega-beast. A mega-beast because it weighed 33kg and was so deep the rear section containing the power and power amplifier section was made to be detachable for easy stowage — but does this disqualify this unit as a Receiver? Technically yes, but hey we’ll make an exception 🙂 (Actually this receiver shipped as a bolted together ‘single’ unit and the kit that allowed for separation wasn’t even available until the year after it was released.)
This rear compartment contained a massive toroidal core transformer and two huge 22,000uf filter capacitors and the power amp. Aesthetically Rotel refused to imitate the competition and produced their own unique look with their yellow/orange back-lit dials and futuristic-industrial styling.
The RX-1603 features included twin headphone jacks, frequency adjustable bass and treble tone controls, high and low filters, stereo and mono controls, dubbing controls, twin turntable inputs and outputs for three pairs of speakers.
While Technics had exceeded Pioneer’s SX-1250 by 5 Watts and Rotel by 20 Watts they had done it with power supply’s of only half the capacitance and of less sophistication than that of the SX-1250. But in a war of metric’s Rotel now held on to claim of having ‘The World’s Most Powerful Receiver!’.
Posted In: Article, Featured
Tagged: `, receivers wars
Some people debate which was the first 100+ watt per channel receiver: The Pioneer SX-1010, the Kenwood KR-9400, or the Marantz 2325?
It doesn’t matter, they are all great receivers!
Great write up on the Receiver Wars. However, it’s a shame that the Sansui G-8000 or G-9000 was not even mentioned because they were actually the 2 most powerful Sansui receivers of the 1970’s.
The 22,000 and 33,000 are NOT receivers. They are a separate power amp with a preamp/tuner.
Yes you are right! I did mention that Sansui (and Rotel) were technically CHEATING but decided to make allowances for it because the G22000 & G33000 are just so AWESOME! Maybe I am being corrupted by modern politics 😉 When I get time I will have to mention the G9000.
An absolutely lovely article. I was a young lad in the 70s when my dad bought a SX-939; not a monster but close to it. I enjoy vintage audio and apparently so do many others!
Very good article well written
Wow. Great info. I run a store in Seattle and I get to see this stuff on a daily basis. Though I haven’t owned most of these monsters I have had a lot of their smaller brothers in the shop including a Marantz 2330, Kenwood KR-7600, Sansui 5050, and many more! Thanks for writing such an easy to read fun article!
Turntables & Trails
I just wanted to say thanks for putting this piece together. I have just entered the world of receivers in hopes of
buying my first. I’m a child of the 70’s, so it really is exciting to enter into this audio sphere. Your article
cleared up the issue of why so many receivers of that era seem to be so sought after, and at such premium prices !
Cheers for a job well done.
I just bought two of the best. Marantz 2325 and Pioneer SX-1250. Waiting to rebuild them so I can hear what music can sound like from them.
A fun read and thanks for putting it together. I’m now a proud owner of a fully restored Marantz. Every cap , diode, transistors, extra soft start relay etc on every board has been replaced.
Let me say, it’s a privilege to hear this and I can’t thank enough the engineer who did this out of passion.
I’m a LUCKY individual to be hearing music so softly at times and thunderous at others while at the same times the delicate details of the music. The cadence , rhythm, attack and decay of handling 15″ woofers on my Klipsch Belle’s on VERY low volume at one in the morning while little one sleep is truly a sign of a great receiver.
Anyway, hearing so much about the musicality of Sansui G-22000/33000 I’ll be looking for one just out of curiosity.
Folks, get a Marantz 2500 fully “off the frame” restoration and you’ll never regret it.
I owned a Kenwood 9600. Great unit. I ran JBL L100s and L166s through it. It didn’t even blink.
Interesting that Harman Kardon stayed out of these wars.
Realistic STA-2080 anyone?
I still own my Pioneer SX-1250. My father garbage picked it for me as a kid in the early 2000’s and to this day I still can’t understand why someone would just throw away a fully working beauty. . . . . Okay a few bulbs were burnt out and three knobs were missing but still fully functional (all fixed up now). Things like this normally are far out of reach for my budget so I feel extremely honored to own such a blessing. The warmth this thing reproduces is inviting even if you’re listing to MP3’s. It will even put most vacuum tube units to shame even through my cheep craigslist speakers. (I plan on getting some used “cheap” Vandersteen Model 2’s for it.) My bias is for the Pioneer but the truth is all vintage high fidelity receivers from this era are truly a class above anything made today. They’re envious inducing for all your friends so for the love of God don’t keep anything like that in your garage.
I have a Pioneer 1280, Sansui 9090 and a Marantz 2325. I love my 9090 and the other two are great. I just prefer Sansui products. I have never turned the volume above 2 and you can’t hear a person next to you. Crisp clean and loud. I also like some of the stuff Luxman put out there.
Nice write up. This is the most extensive chronological account I have seen of the major blows in the war. Most turn into a list of “all the monsters”.
The last page regarding the real purpose of this type of equipment seals the deal on this being a well thought out article.
I enjoyed reading the article. I thought you did a great job compiling the key elements of the receiver war for a historical and educational perspective in a nutshell and included specific specs on specific models of receivers as support . This article wasn’t meant to showcase all the wonderful receivers during that time. There’s other articles and debates on that. Every person involved in the receiver war has a favorite and excuses why others wouldn’t be given the time of day, even if they were better. Right Marantz people?
On another note- I’d like to think the real winners of the receiver war are the receivers that are still going strong, all original , without issues, and without the ‘for its age’ excuse.
I delighted to read these lines. Thank you for resurrecting the genealogy of these timeless monsters.
I’m just one more fan of these machines. Unfortunately in Europe followed the english model – integrated amplifiers and let pass completely these Ferraris…
In my collection i have 2 Marantz 2270, one Pioneer SX-850, one Pioneer SX-950, one Pioneer SX-1050 (bought 2 days ago) and the Sansui 9090, my all time favorite one!
in the future i want to get the SX-1250 and the Sansui9090DB.
Please write an article about the Marantz 2270. He is not one monster receiver, but he deserves it.
It would also be good to write a review about the SX-1050, the little brother of the Pioneer SX-1250.
The Pioneer SX-1050 has “only” 120 horses :0)
Fabulous website! Thanks for all your work putting it together. One correction: Your quoted power of Yamaha CR1000 is wrong. Its correct RMS rating (20-20kHz at 0.1% THD), is 70wpc @ 8 ohms. IHF rating is 100wpc @ 8 ohms. Not “40wpc RMS” and “70 wpc IHF,” respectively, as stated in your article above. For reference, I cite the manufacturer’s original brochure, which can be found in the online HiFi Engine library. Thank you, in advance, for making this correction.
Done! Thanks for the info.
Great job, i am Lucky cause i use à 5760 with infinity kappa, both in a mint condition. Only pleasure and strengh
À french man
I have a pioneer sx1010 and feel privaliged to be a part of the receiver wars and this great era for hifi
The Monsters little family members watched the war from a different side. These models may be known as “Mid-Fi”, “Lo-Fi”, or ‘If-Fi’. If I had way more money then I would’ve bought a Hi-Fi monster.
And eventually I did. Now I have that and everything in between. I love the big receivers but when I use the lower tier audio I’m more at ease since the big ones , if something should happen to them….it’s not that simple and cheap to remedy the situation. There’s more at stake. Then again the rewards are somewhat higher too, although that’s subject to debate.
What I’m saying is let’s not forget the ones in the garage, bedroom, basement, man cave, dorm room, spare room, office, the one you brought to the girlfriends house (future wives?) and the ones she made you get rid of in your house.
Awesome article I love those receiver amplifiers use to own If I’m not wrong Marantz 2325 paired up with Bose 901 produced unbelievable sound me and my friends enjoyed many years to come, it was a magic decades.
Nice article but lacking certain pertinent call-outs.. The monster Pioneer & Technics receivers had fraudulent power output specs, for example the SX1980 actually put out 145W/ch rather than the claimed 270W/ch. Both receivers had robust power supplies but inadequate heat sinking area, and Pioneer was slapped with a an FTC Case & Desist about their fraudulent claims for the SX-1980. Basic problem was that neither receiver would NOT pass the FTS preconditioning tests. When tested rock-cold the SX-1980 would put 270W/ch but… as the heat sink heated up its power output would decrease significantly… The only monster receivers meeting & exceeding the FTC power output specs were the Marantz 2385, 2500 and 2600.. I actually have serial # 0002 model 2600 hand carried back from Japan by a close relative, it is in mint condition and I have turned down offers of >$9,000.. Great product, plenty of power, scope, 5 gang front end, quartz lock tuner, full complimentary output stage, patented servo-controlled heat-sink tunnel output stage…
Hi, and thanks! Interesting… do you have any articles to the support the fraudulent power output spec claim?
I could not find any reference to FTC cease and desist orders other than 1 comment on another website that also lacked any source references.
What I did find was 2 independent lab tests that told a different story:
The folks at Audio Magazine in the September 1978 issue reported on their laboratory tests on the Pioneer SX-1980 using both the older FTC standard and the newer 1978 IHF standard (with the specified warm up). Both their tests showed that the 270 Watt RMS rating was very conservative, with the SX-1980 delivering more than the 270 Watts claimed.
The reviewer went even further to say:
“Though the new [IHF mandated] “Dynamic Headroom” measurement is specified in dB, it should be mentioned that based upon the short-term signal used to measure the 2.3 dB headroom of this amplifier, it was producing nearly 460 watts of short-term power under these test conditions!”
Then there is HiFi Stereo Review, the November 1978 edition that published their Hirsch-Houck laboratory tests of the Pioneer SX-1980 using the new standard – IHF-A-202 1978 which included the prescribed one-hour preconditioning period at one-third rated power, they stated that the unit did not become excessively hot during this stage. Their tests indicated that the 270 Watt rating was quiet conservative with clipping occurring at around 300 Watts with intermodulation distortion measured at 0.045 percent at 300 watts.
I will check in later if I find some independent lab tests for the Technics.
Planar brand quad receiver.
After trying low end Electrovoice EV1144 & Sanyo quads I finished up in 1976 with a (owned by Canadian Electrohome) Planar XR-4120 receiver, rated at 4×30/2×70 watts RMS 20-20 kHz at 0.5% THD, which could handle all quad formats including full logic SQ. I enjoyed RCA CD-4 and had a library of about 20 CD-4 + 40 SQ & 1 QS LPs.
I built my own 4 towers each using Philips drivers-1 8 ohm AD80652-W, 1 AD5061-M, 1 AD2011-S & 1 AD8002 passive radiator, and crossovers using data from Philips published ‘Building Hi-Fi Speaker Systems’ by M.C.Hull. Dual (forget model) turntable with (forget model) cartridge & Shibata stylus compatible with CD-4 high frequency requirements. I also had a joystick 360 degree speaker control. Unfortunately my enjoyment was short-lived, since while on vacation my house was burgled with only my system taken. Presumably one of my kids had been talking about it and one of their acquaintances had unsavoury connections.
Planar were late into the short-lived quad market and went out of business. I remember the hefty 50 lb weight, more than some much higher rated receivers, even although the power transformer was toroidal.
As an example of the advertising problem, before I bought my Planar XR-4120 I had a large French Provincial cabinet (by Drexel) Motorola credenza since my wife liked it as a piece of furniture. Multiband radio, turntable brand I forget, cassette player (motherboard Nakamichi) and 3-way (12 inch woofers) speakers. Advertised as 350 watts, but this was dynamic power rating for 2 channels, no distortion figure quoted, which translated into less than 20 watts RMS/channel into 8 ohms. European ratings had for years been based on continuous RMS at specified distortion levels, usually into 8 ohms. As a ‘Brit’ with exposure in family radio & TV business since age 10, I was familiar with both systems, living in Canada 1963-72 & 1976 on.
Just wanted to congratulate you on your FANTASTIC Site. Who is the brilliant Hi-Fi Journalist who wrote the article on the Receiver Wars ?
Thanks for your feedback, much appreciated!
I am glad you are enjoying the site 🙂 This site is a hobby of mine to spread the love of vintage HiFi, unfortunately I haven’t had the time to contribute to it lately.
Where is famous Akai ? This company also enjoined receiver wars with model AA 940 (classic two channel) stereo . Must added in this competition .
While I do love Akai gear from this period, they did not take part in the Receiver Wars. The war started with the 1974 100 Watt RMS per channel Pioneer SX-1010 while the Akai AA-940 was 66 Watts per channel. Likewise I do not include the celebrated Marantz 2270. Akai actually adopted a unique market approach and instead of competing in the raw power race, Akai opted to offer quadraphonic sound in their top of the line models.