Inside Pioneer amps

[Deleted member 48726]

Inspired by the "Inside Yamaha amps" thread; Inside Yamaha amps, I think it would be cool to start one with Pioneer amplifiers.
Both Yamaha and Pioneer launched their first HiFi product in 1953 / 54. Even though Yamaha holds the highest regard with me, Pioneer comes in at second place. There really is some high quality units from the past. I must admit I haven't been keeping up to date with the newer Pioneer stuff so I am referring to the old(er) stuff.

Any pictures of Pioneer amplifiers are welcome.

This OP is really lame as I don't own any Pioneer amplifiers. -It's all up to you guys!

 

[mhardy6647]

umm, I don't/haven't owned too many either... Not a big fan, really.

Here's a bit of the innards -- to wit, the stereo power amplifier section -- of a Knight (Allied Radio) 333 receiver -- a "badge engineered" variant of the Pioneer SX-34 low-end, low-powered stereo receiver of the mid-1960s. Push-pull 6BM8 for about 8 wpc. Kind of a spaghetti monster mess inside. Replacing those brown coupling caps in this was a bit of a challenge.

 

[Deleted member 48726]

umm, I don't/haven't owned too many either... Not a big fan, really.

Here's a bit of the innards -- to wit, the stereo power amplifier section -- of a Knight (Allied Radio) 333 receiver -- a "badge engineered" variant of the Pioneer SX-34 low-end, low-powered stereo receiver of the mid-1960s. Push-pull 6BM8 for about 8 wpc. Kind of a spaghetti monster mess inside. Replacing those brown coupling caps in this was a bit of a challenge.

That looks.. Rough.

 

[bloodshoteyed]

That looks.. Rough.

at least the one taking the pic was prepared with some fire equipment stuff (hope it wasn't just a ruler, tho)

 

[Gorgonzola]

umm, I don't/haven't owned too many either... Not a big fan, really.

Here's a bit of the innards -- to wit, the stereo power amplifier section -- of a Knight (Allied Radio) 333 receiver -- a "badge engineered" variant of the Pioneer SX-34 low-end, low-powered stereo receiver of the mid-1960s. Push-pull 6BM8 for about 8 wpc. Kind of a spaghetti monster mess inside. Replacing those brown coupling caps in this was a bit of a challenge.

View attachment 240665

Holy crow!!! You mention that this component was low end. In this day & age it's hard to imagine anything with this much point-to- wiring being "low end" on account of the fine and complicated of manual work involved.

 

[Vini darko]

Carrying on with the low end theam. Here's my M-J200 from about 1990. Wich is very basic. It has received some light modification , converted to rca, bigger filter caps and a normal mains lead.

 

[mhardy6647]

Holy crow!!! You mention that this component was low end. In this day & age it's hard to imagine anything with this much point-to- wiring being "low end" on account of the fine and complicated of manual work involved.

Here's the Allied/Knight morph. The Pioneer morph (SX-34) was also sold in the US (as also was the SX-34B, which had a meter instead of the magic eye tube for FM signal strength). It was Allied's entry-level receiver for a few years in the mid to late 1960s.

source: https://www.alliedcatalogs.com/flipbook/1969_allied_radio_catalog.html page 22

 

[Koeitje]

Holy crow!!! You mention that this component was low end. In this day & age it's hard to imagine anything with this much point-to- wiring being "low end" on account of the fine and complicated of manual work involved.

You could ask extra for this kind of garbage these days.

 

[mhardy6647]

Pioneer CT-F1000 cassette deck.
Outside.


Inside.

Next model sequence (a few years later), the CT-F900 was, very briefly, the TOTL Pioneer Cassette deck. Not as nice inside nor out.






Here's a second-half of the '70s entry level Pioneer stereo receiver, the SX-450. The sales leader of the line was probably the SX-650 (35 wpc), but the 450, due to its low cost, was pretty common, too. 15 wpc. My recollection is these were about $150 from the discount hifi chains of their era (ca. 76-77).



From top to bottom, these four (more or less) entry level receivers of the second half of the '70s are:
Technics SA-80
Pioneer SX-580
Pioneer SX-450
Yamaha CR-240

Here's the innards of that SX-450.






In fairness, the big Pioneers of the SX-xx50 model line were pretty impressive inside. I have an SX-1050 upstairs, but I don't think I have a photo of its entrails. Its big brother, the SX-1250, was -- I must admit -- pretty darned well built.

 

[mhardy6647]

mmm... I have weird things at my house...

 

[Gorgonzola]

mmm... I have weird things at my house...

I had one of those Pioneer CT-F900's for a while years ago. The damned thing kept breaking down: the clutch mechanism repeatedly failed and attempted repair worked only for a short time.

 

[mhardy6647]

I had one of those Pioneer CT-F900's for a while years ago. The damned thing kept breaking down: the clutch mechanism repeatedly failed and attempted repair worked only for a short time.

These two both work -- well, they did, last I knew.
That said, yes, both these, and the CT-F1000s, don't age well. There are plastic (maybe nylon?) parts inside that get brittle with age. I -- ahem -- actually had two CT-F1000s, too. I gave one to a local guru who, as a COVID project, ended up getting interested in tweaking & restoring (resto-modding, even) some vintage, good quality cassette decks. He spent a protracted period lovingly restoring the CT-F1000 (which did work, but certainly wasn't healthy), got it to a pretty robust level of performance, but quickly moved on to some much more modern Sony 3-head decks from the last flowering of "good" cassette decks (early-mid 1990s). Those were likewise pretty needy, as I recall.

... but I digress.

 

[ronniebear]

Pioneer SX-750 receiver, still in my collection, turns on but has an annoying power-supply hum. For what it's worth, this FM tuner (fully aligned three years ago) seems to have superb adjacent-channel selectivity and low distortion (in an area with a lot of trees and some multipath), and one of the best-sounding and sensitive AM tuners I've ever heard (other than a General Electric Super-Radio).

 

[restorer-john]

Here's one of my Pioneer babies:

Teaser picture- identify this amplifier

Brand is correct Don! The SA-9100 however is from 1973/4 and looks like this: This amplifier is from the late 1980s. Ain't no good at keeping track of all the new-fangled stuff, mate. :) It all looks sooo tantalizingly familiar, and 1980 is the time I was actually in the audio business...

www.audiosciencereview.com

 

[mhardy6647]

Pioneer SX-750 receiver, still in my collection, turns on but has an annoying power-supply hum. For what it's worth, this FM tuner (fully aligned three years ago) seems to have superb adjacent-channel selectivity and low distortion (in an area with a lot of trees and some multipath), and one of the best-sounding and sensitive AM tuners I've ever heard (other than a General Electric Super-Radio).

P/S hum even at zero volume? Main P/S filter capacitors, methinks.

Nothing against your Pioneer, nor the GE SuperRadios but (and FWIW) the best sounding AM tuners here are of rather... older tech. Pretty 'hot', too.
Here's, perhaps, the best of the lot in those regards.

The era of "AM-FM simulcast stereo" broadcasts (in the US), shortly before the FCC licensed compatible FM MPX stereo, produced a raft of AM-FM component tuners (and a few receivers, too) with remarkably good AM sections. This Sherwood was not one of them, but the AM radio section of it is very, very good.

That said, I have a early-mid '70s vintage Sansui 5000A soiled solid state receiver with a surprisingly good AM tuner in both "radio" and "audio" terms. Surprised me, it did!

... but I digress*.

_______________
* Me?!? Inconceivable.

 

[ronniebear]

P/S hum even at zero volume? Main P/S filter capacitors, methinks.

Nothing against your Pioneer, nor the GE SuperRadios but (and FWIW) the best sounding AM tuners here are of rather... older tech. Pretty 'hot', too.
Here's, perhaps, the best of the lot in those regards.

The era of "AM-FM simulcast stereo" broadcasts (in the US), shortly before the FCC licensed compatible FM MPX stereo, produced a raft of AM-FM component tuners (and a few receivers, too) with remarkably good AM sections. This Sherwood was not one of them, but the AM radio section of it is very, very good.

That said, I have a early-mid '70s vintage Sansui 5000A soiled solid state receiver with a surprisingly good AM tuner in both "radio" and "audio" terms. Surprised me, it did!

... but I digress*.

_______________
* Me?!? Inconceivable.

You are right that a handful of AM-FM component tuners from the 1958-62 "simulcast stereo", designed to allow the user to feed one channel of output audio tuned to an AM frequency and another channel tuned to an FM frequency, prompted real excellence in AM tuner circuitry.

Interestingly, when I was just a baby my father purchased a Harman/Kardon "Award Series" TA-5000X receiver as part of a custom-packaged stereo system. The 1962-vintage TA-5000X which had separate tuner columns for AM and for FM, likely reflecting the product development stage when "simulcast stereo" capability might have been contemplated. Ultimately, as the FCC-approved and newly-introduced Zenith FM multiplex system had rendered "simulcast stereo" moot, the TA-5000X receiver omitted "simulcast stereo" and only tuned one FM or AM station at a time. Although I recall the AM tuner had very good performance, I don't recall it having particularly extended frequency bandwidth compared to FM. We had that receiver in the family home until about 1980.

 

[emaspac]

my Pioneer A09.. one of the best integrated amplifier produced by Pioneer, 1991

 

[mhardy6647]

You are right that a handful of AM-FM component tuners from the 1958-62 "simulcast stereo", designed to allow the user to feed one channel of output audio tuned to an AM frequency and another channel tuned to an FM frequency, prompted real excellence in AM tuner circuitry.

Interestingly, when I was just a baby my father purchased a Harman/Kardon "Award Series" TA-5000X receiver as part of a custom-packaged stereo system. The 1962-vintage TA-5000X which had separate tuner columns for AM and for FM, likely reflecting the product development stage when "simulcast stereo" capability might have been contemplated. Ultimately, as the FCC-approved and newly-introduced Zenith FM multiplex system had rendered "simulcast stereo" moot, the TA-5000X receiver omitted "simulcast stereo" and only tuned one FM or AM station at a time. Although I recall the AM tuner had very good performance, I don't recall it having particularly extended frequency bandwidth compared to FM. We had that receiver in the family home until about 1980.

Well there's not much room for audio bandwidth on the US AM (broadcast) band!
Some of the AM tuners made the best of a difficult band, though, for sure.

I do have identically one Pioneer tuner -- and it does receive the "AM" band... but I don't (at least yet) have a photo of its innards to contribute to this thread.
Here's its outards, though.



You know -- to stay, kinda, sorta, on topic.

 

[Vintage. Dude]

Pioneer c90/m90a

C90 preamplifier 3 transformers, dual mono
M90a 2 transformers, dual mono, non switch

 

[TheBatsEar]

Nice pics so far, sadly i don't have any Pioneer gear to contribute.