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Pioneer SX-838

AM/FM Stereo Receiver (1974-76)

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Pioneer SX-838


The Pioneer SX-838 is a 5OW RMS stereo receiver featuring PLL FM MPX, precision equalizer, switched-turnover tone control and direct-coupled OCL power amp.

Depend on Pioneer to provide the latest electronic advances and the SX-838 stereo receiver is a perfect example.

Its FM tuner offers high sensitivity and excellent rejection characteristics thanks to its front end equipped with a frequency-linear 4-gang variable capacitor and two MOS FETs.

The FM IF section has a 6-stage limiter and phase-linear ceramic filters.

For the FM MPX demodulator, Pioneer uses a new PLL (Phase Lock Loop) circuit with an IC.

The results of these state-of-the-art touches are immediately apparent: FM sensitivity of 1.8uV, better than 80dB FM selectivity, capture ratio of 1.0dB (all IHF) and better than 30dB stereo separation (50 to 10,000Hz).

The Phono equalizer in the SX-838 provides accurate reproduction of all the sounds in any record groove by assuring no more than ± 0.3dB deviation from the RIAA curve.

In terms of power, the unit produces 50W + 50W of continuous RMS power (both channels driven at 8 ohms) with total harmonic distortion of less than 0.3% - remember that this figure is measured and guaranteed over the entire spectrum from 20 to 20,000Hz.

The SX-838 is distinguished from all other receivers in its price range by offering switched-turnover flexibility in its tone control operation, permitting the creation of a variety of tonal characteristics to match your room's acoustics or your mood.

And when it comes to versatility, it reproduces no less than six program sources (AM, FM, Phono 1, Phono 2, Mic and Aux).

It also has two stereo sets of tape deck connections with monitor switching (and deck-to-deck duplication).

If you wish, use the noise-reduction adaptor terminals to connect a third tape deck.

This unit is provided with a special Recording Selector, enabling you to record FM broadcasts while listening to the disc reproduction and vice versa - a unique time-saving device for your listening pleasure.

A total of three pairs of stereo speaker systems can be connected to the SX-838 (with a front-panel switch to use any one or any two of them at once).

Speaker selection and source indicators are provided on the attractive dial panel.

It's a Pioneer value from top to bottom, and your best buy for stereo receiver economy.


Tuning range: FM, MW

Power output: 50 watts per channel into 8Ω (stereo)

Frequency response: 10Hz to 70kHz

Damping factor: 45

Input sensitivity: 2mV (mic), 2.5mV (MM), 150mV (DIN), 150mV (line)

Signal to noise ratio: 65dB (mic), 70dB (MM), 95dB (line)

Output: 150mV (line), 30mV (DIN), 1V (Pre out)

Speaker load impedance: 4Ω to 16Ω

Semiconductors: 4 x FET, 4 x IC, 43 x transistors, 24 x diodes

Dimensions: 520 x 175 x 420mm

Weight: 16.2kg

Accessories: FM T-type antenna

Year: 1974


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Reviewed Jul 31st, 2018 by Fsatsil

I only use the amplifier section of the Pioneer SX838. My Dac/Preamp is connected directly to the amplifier section and the sound is incredible. It’s only 50wpc but that seems conservative, the amp has plenty of power to drive even larger floorstanders. The sound quality is very clean, clear, and smoooooth.

Reviewed Mar 03rd, 2018 by audiophilesean

This BEAUTIFUL AMAZING piece of equipment was given to me for helping a friend move in 1994. It needed some love and attention. At the time, I had an SX-424 it was a decent stereo but after I had the 838 repaired, the 424 became the garage stereo and I have enjoyed annoying the neighbors with the 838 since!! I just got it back yesterday, as it got damaged (by accident) when I moved into my new house. I feel like I am 23 again when I hit the power switch and smelled the most wonderful smell EVER!! I am looking forward to annoying the new neighbors a half of a mile away from me starting today!!

Reviewed Mar 01st, 2018 by pieter1234

Very good receiver, looks very cool, it is also well build.
I had mine completely restored.

Sound: Smooth treble, slightly recessed mids, deep strong bass, warm sound. Black Sabbath sounds amazing on it.

It is very good, but my Sansui Six definitely beats it on detail and midrange.

Reviewed Dec 11th, 2012 by guest

When I bought my Pioneer SX-838 (for $300 in 1976) it was the Tech Hifi demo for speakers, it was a year old. It was left on continuously for that period. They had to sell it, as the 1977 models were going to brushed aluminum face. This receiver was the staff favorite, and I soon learned why. This relatively small 50 WPC, OCL amp really kicks butt. It will drive almost any speaker on market at that time (Bose 901 being the notable exception). It's real worth is in it's warmth, detail, low distortion, low noise, large dynamic range, large selection of inputs and triple pair of speaker outputs. I spent about a year comparing performance specs and price, auditioning the likes of Yamaha, Onkio, Kenwood, Sansui, Marantz, McIntosh, Technics. The Pioneer sounded as good as the pricer units and much better and the similarly priced ones. It's been 36 years of listening pleasure. If you can find a good clean used one under $300, you can't go wrong. Even one the needs a little work is worth investing as most parts and service literature are still available and it is easy (for service professionals) to work on. I have upgraded my music systems serval times over in 35 years, but I could never part with this little gem.



re: SX-838

Hi everyone!
Thank you for your reviews and comment and off cource the manuals.

I bought one last week without any pre-researching. I've just choose to trust to seller. He told me that this is what Im looking for. And after 1 week with 41 years old sx-838 Im sure that this is a good device for my home and ears(and eyes too actually)

And reading your opinions made me more satisfacted.

I've paid for about 1.100$ (in Turkey)

If anyone read this I want to share my speakers too and if I can get any feedback it would be great. Speaker is RTR Series II (HPR-12M Magnums) I'm totally a newbie so I hope those guys are a well matched couple.


My free Pioneer SX-838 is clicking...

Today at a rummage sale I was given a Pioneer SX-838 for free, admonished that it had a weird volume problem.

It LOOKS very clean, inside and out, but a couple knobs are bent, like it may have been dropped.

Here's the problem - has anyone experienced anything like this:

when I plug a cassette player into it - in the AUX or TAPE 1, actually anytime there's a signal from any input, and the Volume knob is above 0, there's a persistent mechanical clicking sound.

Is this a protective circuit (page 9 number 11 in the manual)?

Seems to me, there's a gigantic hum coming from somewhere, that's being cut off to save my speakers.

Any suggestions?

A loose grounding screw maybe ...where would that be?

Thanks for any help,


PS Thanks for the service manual! I'm diving in right now.

Is there an owner's/user manual out there somewhere?

Just bought the SX838 but need a user manual to help resolve some problems - I'm probably just not using the correct settings.

Thanks a lot

I have been searching this manual for a quite long time, and finnaly i found it.

Thanks a lot for the guy who put it on the web.

Great greetings for the site!!!!!

This website is not affiliated with or sponsored by Pioneer. To purchase SX-838 spares or accessories, please contact the company via their website or visit an authorised retailer.