help identifying mystery amp

[elmore_lewis]

I just nabbed this cheapo stereo amp and have spent a couple hours trying to ID it's make so I can find a bit of info on it. There are no markings other than on the PT and OT which are

standard Woodward-Schumacher numbers. The tubes are all Hammond labeled but that may not be relevant. I tried cross referencing tranny #'s but to no avail.

 Is it even worth it ? or should I just tear it apart . I thought it might be a good candidate for a 18 watt lite rebuild.

 Maybe someone could point me in a more prosperous direction to look. 

PT # 606-027     TR-62

OT #606-026      AT-61


 thanks in advance,

EL

[sluckey]

The top looks like a simple 2 channel (stereo) single ended amp, ie, two amplifiers driving two speakers.  None of the stuff on the front is original. The PT is probably good for an 18W lite, but the OTs are more like Doug's Schedule 40 GA-5.

[DummyLoad]

if the #'s given are EIA codes, then transformers were likely wound by woodward-schumacher  - IIRC, they also wound fender iron.

http://www.triodeel.com/eiacode.htm

looks like a fun little amp. 

[PRR]

My guess is a 1962 walnut-veneer home console stereo, minus the tuner, changer, and walnut console, and re-worked at some later time.

It looks 90% the same as an RCA console power-amp I once knew. GE and everybody made very similar products.

The circuit will be the 2nd and 3rd stages of a Champ, only with EL84, twice for stereo. Usually pushed to the limit, around 6 sorta-clean Watts.

The OTs are plenty good for guitar.

The sensitivity is too low for sensitive action, you need like a Champ's first stage, or re-rig the two stereo drivers (12AX7) as mono preamp + driver.

You could replace the OTs with a new push-pull OT and totally re-wire, "18W"-like. Might be 14W-15W. Might not be any "better" than strapping the two SE OTs together for 12W "Champ" rig.

[66merc]

Folks,

Pardon my ignorance, but how would one strap the two output transformers together.  I'm having a hard time visualizing how that would be done.  Or is it simply tying the two speaker output taps together?  I have never seen that done.

Thanks

Eric

[DummyLoad]

...how would one strap the two output transformers together.

see attached...

[elmore_lewis]

well for what it's worth I found out it's a Magnavox model 8601.....and indeed was in a very nice cabinet !


  EL

[Willabe]

I would'nt mind having that in my house.     

Won't find that at Wally World.       


        Brad         
         

[PRR]

The RCA console I knew was just that shape and size, same sliding panels on top, but lacked the tambour door record storage and had large basket-weave grill all the way across. I suspect the Mag 8601 was intended to sell at a higher price than "my" RCA, and that RCA probably had a comparable more-fancy model.

All these things, mostly the radio company put out cabinet specs for bids. There were always furniture mills who could run such fancy-work in odd moments, cheaper/better than the radio company's in-house low-price cabinet shop. Perhaps the styling ideas came up from the furniture industry; if my memory was better I could maybe tell what year that was styled, by the cut of the top edge and those marvvy fake handles.

The fact the rectyfier says "CBS" may be a clue? Did CBS buy Magnavox? Proves nothing, because CBS also ran a replacement-tube racket.

The electronics were never as snazzy as the cabinetry. There were some 1-Watt/ch 25C5 jobs, but when the EL84 was nicknamed 6BQ5 the hi-price jobs all went with that.

[HoodratShinobi88]

I built my baby outta a 60's motorolla record player amp almost identical to that. I scrapped everything after the rectifier & then copied half of the schedule 40 & bought a new OT from Mr.Hoffman. Sounds so good listening is sinful.

[HoodratShinobi88]

I guess this would fall under the "champ" type PRR was talking about. You can see where the Second OT and el84 was. I forget why I opted to build it the way I did but It cost <$20 :D

[elmore_lewis]

well I made the input mono and wired the output transformers in series as suggested and hey....! it worked . Can that method be used in a PP set-up as well ?

[DummyLoad]

...Can that method be used in a PP set-up as well ?

absolutely! 

[jeff]

 If you use it as a PP I think you'd have to reverse the wires on one side of one of the OT's to keep it in phase.

[elmore_lewis]

   hey thanks guy's ...as always, a good learning experience !