Vintage Japanese amp find - trying to identify (pre-production prototype?)

[OutlawSun]

Poking around there looks like there was company called American Electronic Laboratories (AEL) that pops up on the radio museum site but there's not a lot of info. Only blurb on what they did was that they made "measurement equipment, antennas, antenna masts and mounting adaptors. Different divisions with different products." It's a complete long shot idea but maybe a company like that at some point toyed with the idea of diversifying and getting into audio industry when it was hot if we're leaning towards it being a prototype and/or something made for a third party looking to just re-badge Japanese made gear. Would be nice if there was more history about where the previous owner got it.

 

[evendine]

There's a bunch of early/mid 70s amps that came out of Japan built in the Roland Electronics plants. We had Challenge and Rambler (check out the SA-8200) and that AEL DX747 looks to be a variation on those. I'm not sure of the relationship with Nikko (badged as Peak here), but there was some crossing over there too. The amp in question looks all the world like an early Roland Electronics Corp design. The other possibility is an Inkel.

It seems many of the variations of these amps were badged for large HiFi chains around the world and sold as house brands.

Not a prototype, just a quality amp, made in relatively small numbers, so it may look a little rough in areas.

Yep, that's kind of where the discussion started John. The LencoHeaven link in the original post includes a post which suggests the AEL might be a rebadged OEM product. The problem is the number of features found in the amp which suggest active reworking of the design, which evidently hadn't stabilised (also listed in the original post and illustrated in the pics). I would have thought an OEM rebadged unit would be based on a stable design (if only to avoid returns) and supplied ready to sell by the client company. You would certainly expect them to have gained safety conformity certification and there's no evidence for that.

Have had a look for the Roland / Inkel / Nikko amps you mentioned, but can't find any that have much in common - could you maybe post some examples? Certainly agree that the Pioneer SA-8200 has much more in common, although nothing like the striking similarities the AEL CX-747 has with the Pioneer QX-747, as described above.

Interesting to contrast the interior of the SA-7100 (only one of the range i could find) below with the AEL - this is very much a stable design, by the look of it...



...and here's the SA-8100 (can't find the 8200):

 

[evendine]

Poking around there looks like there was company called American Electronic Laboratories (AEL) that pops up on the radio museum site but there's not a lot of info. Only blurb on what they did was that they made "measurement equipment, antennas, antenna masts and mounting adaptors. Different divisions with different products." It's a complete long shot idea but maybe a company like that at some point toyed with the idea of diversifying and getting into audio industry when it was hot if we're leaning towards it being a prototype and/or something made for a third party looking to just re-badge Japanese made gear. Would be nice if there was more history about where the previous owner got it.

Certainly a possibility - will have to check out American Electronic Labs. Might also be interesting to look into the background of designers who worked for both Pioneer and Sansui around that time? Haven't checked, but guess there may be a history somewhere on the web.

The person i bought it from didn't have any info, unfortunately (see: http://www.ebay.co.uk/itm/Vintage-A...-Fi-Seperate-SPARES-OR-REPAIR-QQ/202208760160). We do have a couple of other leads though - the guy who was asking for info about the very same amp on LencoHeaven in 2016 (where did he get it?) and slimecity's HFE post wrt the 'Maskintosh', which looks a very similar beast. Will try to get into it tomorrow, time permitting...

 

[OutlawSun]

There’s a strong resemblance to project one gear in some areas like the light and how the headphone jacks look. Even the stereo solid state placement is in similar location and flowing font. Even the case on one looks similar to that lenco link.

 

[restorer-john]

Very similar to the Project One Mark XX and the Mark XX1 and XXX

Consensus was it was the house brand for Playback Audio I believe.

 

[evendine]

Yep - that's the amp over at HifiEngine that SC discovered: the 'Maskintosh'

Indirectly via that link, discovered that the Project One amps appear to be a product of a US company called Allied Radio, specifically their industrial division, Allied ELectronics (hence the AEL logo?). In the early days, Allied' Radio's 'house brands' were apparently designed and built by Pioneer, but later were manufactured by a (currently unknown) third party sometime after they were taken over by Radio Shack (Tandy Corp) in the early 70's and Allied Electronics division was divested (see: http://www.quadraphonicquad.com/forums/showthread.php?16959-Remembering-Allied-Radio + http://audiokarma.org/forums/index.php?threads/project-one-ever-hear-of-them.494472/)

It seems we were both right - the AEL appears to be a prototype for what became the Playback Project One series of amps. Who did the design work is still open to question, as everything about the build shouts Pioneer / Sansui. I suppose such matters are generally commercial secrets, so perhaps it won't ever be known who did the original work for sure, but my money's on Pioneer's design team.

The following pics show the stable design for the amp in production form, with several elements of the early AEL prototype added / removed, simplified wiring (no wire-wrap evident), PCB's redesigned to minimise footprint (note the introduction of silk screens), the usual single brand (Panasonic) electrolytics throughout, cheaper switch gear / controls + lower quality semiconductors / components generally...

 

[restorer-john]

Interesting for sure. The amplifier modules are a great design- nice and simple. I've got some Teac modules of the same basic topology and modular design.

I'll dig them out for a pic. Very similar style PCB construction.

 

[evendine]

Thanks John - would be good to see those

 

[gslikker]

The seventh picture from the top (brown one lighted from the back) screams Pioneer too, because of those bad little blue Sanyo solid alu caps.

 

[evendine]

The seventh picture from the top (brown one lighted from the back) screams Pioneer too, because of those bad little blue Sanyo solid alu caps.

Yep - those are very unusual - seems you've seen them in other Pioneer amps. Are they actually solid electrolyte, as in OSCONs do you know?
0.22uF @ 25v is not a good size for an electrolytic, although every one i've tested works, but generally has a drifted value, high ESL / leakage...

 

[evendine]

It's interesting that according to the QuadraphonicQuad thread, Allied Radio was bought by Radio Shack in 1940 who were ordered by the FTC to sell Allied in 1974. After RS took over in '70, Pioneer stopped manufacturing equipment for Allied (having done so for many years previously), as it would clearly have damaged their brand to be associated with RS. However, when the Allied Electronics division were divested in 1974, is it possible that Pioneer and AEL renewed their former collaboration? Could it be that Pioneer designed and prototyped the CX-747 for their own range, but decided to sell the rights to AEL as they had changed direction in '73 / '74 towards quadraphonic equipment, meaning the CX-747 no longer met marketing requirements? The Pioneer QX-747, was a quadraphonic tuner released in 1974 and the oldest capacitors in the AEL CX-747 date to May 1974, although interestingly, some date back to 1972.

http://www.quadraphonicquad.com/forums/showthread.php?16959-Remembering-Allied-Radio

Apparently, Allied Electronics was bought by a UK company called Electrocomponents in 1999 (who own Radio Spares, also known as RS Components) and are still trading. I actually have an account with RS, who have a very good in-house support team. Might be an idea to give them a call and see if they have any further info...

https://en.wikipedia.org/wiki/Electrocomponents

 

[dshoaf]

Folks, nice discussion. Back in the 70s, there were marketing trade magazines for the audio business. In the back of those publications were small ads placed by Japanese, Taiwan and other Asian manufacturers offering 2 week turnaround for prototypes of one's own specification. They would build to a faceplate layout you specfied, you could supply the brand name, logo and even the layout of the rear panel. Then, specify the power level you wanted, the switch complement and, voila!, you'd get prototypes (for a set up fee). Then, if you liked it, you could order in mass quantities.

These were the guys who made much of the dime store, discount store and other brands of gear oh and private label stuff, too. The item in this thread appears to be of that nature. It is actually quite high quality given the sockets for boards. In any case, I would not consider them rare but unique.

Cheers,

David

 

[evendine]

Interesting variation on the 'rebadged OEM' theory David :0)

The history of the manufacturing relationship between Pioneer and AEL + the use of high quality components also used in other Pioneer amps of the time would seem to suggest otherwise, though.

As an engineer, I think it unlikely that an amp of this quality could be turned around in a couple of weeks, or that such a manufacturer would have to the tooling, or choose to replicate in every detail a faceplate with switch-gear and control components identical to a high-end design which had just reached the market, i.e. the Pioneer QX-747. Surely that would be opening themselves to serious litigation?

Seems this 'Linear Design' amp (similar to the Rambler brand, et al) might be an example of the type you're suggesting - a very different level of quality to the AEL:

 

[gslikker]

Yep - those are very unusual - seems you've seen them in other Pioneer amps. Are they actually solid electrolyte, as in OSCONs do you know?
0.22uF @ 25v is not a good size for an electrolytic, although every one i've tested works, but generally has a drifted value, high ESL / leakage...

See post 205 here where another forum member took them apart. these are white Elnas but they are alike. Myself, I have no knowledge about such capacitors and how they would compare against OSCONs, except they DO leak (at least, they leak beyond expectation and more than good normal alu electrolytics). As they are used for coupling in sometimes very low current circuits, knowing them being leaky makes any knowledge about ESR or value obsolete I did not measure that and they went in the electronic waste bin right away.
Maybe they were a cheap alternative to tantalums.

http://audiokarma.org/forums/index....byss-yes-can-it-get-any-better.610004/page-11

 

[evendine]

See post 205 here where another forum member took them apart. these are white Elnas but they are alike. Myself, I have no knowledge about such capacitors and how they would compare against OSCONs, except they DO leak (at least, they leak beyond expectation and more than good normal alu electrolytics). As they are used for coupling in sometimes very low current circuits, knowing them being leaky makes any knowledge about ESR or value obsolete I did not measure that and they went in the electronic waste bin right away.
Maybe they were a cheap alternative to tantalums.

http://audiokarma.org/forums/index....byss-yes-can-it-get-any-better.610004/page-11

The Sanyos appear to have the same construction - black potting compound rather than the usual electrolytic rubber seal. Seems there are reasons why tantalums were used rather than electrolytics, or film capacitors. Apparently, they have relatively high ESR (which can be useful in some situations) and their own distortion characteristics which again may suit certain design contexts (see: http://www.diyaudio.com/forums/parts/56015-tantalum-capacitors-signal-path.html). Clearly long life was one consideration - can't imagine an electrolytic of that size which would still be working after 44 years in the case of the AEL. Seems quite a few high-end designs used them for low level coupling in those days. Don't think they were cheap compared to electrolytics / film caps - a different era, but the DIYAudio thread mentions $300 for a single MIL-Spec NOS tantalum!

 

[KentTeffeteller]

This looks like a 1966-1970 Japanese amplifier to me in how it is built, and the style and technique of construction.

 

[evendine]

This looks like a 1966-1970 Japanese amplifier to me in how it is built, and the style and technique of construction.

My first impression was the same, but checking capacitor dates gives a range of 1972 - 74...

 

[KentTeffeteller]

Wonder if this is a design from the era I quoted, but built much later (which would put your capacitor dates as correct). Meaning a bit retro.

 

[OutlawSun]

Definitely leaning towards it being Project One house brand related. From looking around speculation tends towards it being a pioneer house brand that popped up in the mid 70s it’s kind of hard to find firm dates though. I’d imagine they would have had stocks of caps for whatever R&D so could explain the mix of ages. Also the QX-747 came out in 73 so the knobs would have been in production. So maybe it’s a late prototype. Wish I could find firm dates on Project’s existence.

 

[c_dk]

Back in 1977 while in college I worked at a Playback store.....the Project One equipment did have a Pioneer look to it externally but was usually quite different internally.

A number of months ago I stumbled upon a picture, I think here on AK, of a project one receiver look alike but in black labeled as a Telefunken......obviously for the European market.