Stephens Trusonic id?

hogwylde09

Vintage Tube Hi-Fi Rules
Subscriber
20170921_170731.jpg Wound up with these from a lady who's father or grandfather must have been a audio enthusiast. Got a Dynaco Pas and FM2 in the deal also.
I really don't want to pull the backs off of the Karlson pressboard cabinets. The wood is fragile, chips easily and a lot of slotted head tapered wood screws.
The Klipsch kg3 really compliment the huge amount of bass and hf these huge cabs have. Both very high efficient. Takes very little power to drive them.
Just don't have room to get them separated for real evaluation.
 
I put use to the other components. Dynaco Pass, a ST-70 I rebuilt. The FM2 is on my work bench now. This is my "bedroom system"20171001_164016.jpg
 
View attachment 1029832 Wound up with these from a lady who's father or grandfather must have been a audio enthusiast. Got a Dynaco Pas and FM2 in the deal also.
I really don't want to pull the backs off of the Karlson pressboard cabinets. The wood is fragile, chips easily and a lot of slotted head tapered wood screws.
The Klipsch kg3 really compliment the huge amount of bass and hf these huge cabs have. Both very high efficient. Takes very little power to drive them.
Just don't have room to get them separated for real evaluation.
 
They are 15's. Need to open a cab. No L pad on the outside of the cabs anywhere. Just those old style phenolic junction terminal.

I understand there is a huge following in Japan for these. I Googled a pair 270000 Yen. Don't know if that was a typo. That would be insane.

Was hoping Hunter00 or Reverb could chime in
 
Last edited:
Hogwylde09,

I think you've got it, that's certainly the front of a 150cx. Odd that there's no l-pad for the 5kt tweeter though. It could very well be in the cabinet dangling somewhere. The owner probably just set it to where they liked it, and that was that. The crossover for the 5KT surely has drifted caps. I haven't had the opportunity to open one up yet, so I'm no help there.

Right now, I've got my Trusonic 80FR project front and center in the living room. Badass little rigs. I can't even imagine what the 15" versions sound and feel like. My 120FR's are still loose and in my treasure pile. I'm waiting to find another matched pair of 80FR's so I can build a 3-way with them.

Biggles
 
Look like 150CX to me. Check very carefully to make sure the tweeters are producing. The cone is driven at full range so it will be outputting some highs too. Unless you use the "paper tower roll to the ear" trick, you may think the tweeter is playing when it actually is not. I was burned by that when I bough my original set.

There should be a adjustment canister somewhere. It will have 3 wires (green, red and black) The terminals on the woofer feed the woofer directly (full signal) and it sends a ground (black wire) and a full-range signal (red wire) to the adjuster. The crossover inside sends the tweeter signal back to the concentric mounter 5kt tweeter in the woofer via the green wire. The older style canisters are aluminum and have a rolled-edge to seal them up. Two of my 150CX have this style canister. I have opened one of them to check it because the tweeter is not working - turned out the tweeter itself is open. The crossover I opened is populated with very nice poly caps so not sure if they need to be replaced or not. I recently got a third 150cx here in BT and it has a plastic, sealed (?) canister. The theory was to replace my bad 150cx with a functional one but unfortunately, it's tweeter is open as well. The plastic canister is a newer version and it's pretty neat in that the wires from the woofer have a connector on it so it just plug right into the back of the canister. The older version cannot be easily disconnected IIRC.

I am in an interesting situation because I now have the "freedom" (if that is a correct use of the term) to ditch the Stephens 5KT's and maybe use a modern dome in their place to provide a better dispersal pattern. I would leave the 5KT's in place just steal the tweeter signal off the back of the canister to feed different tweets. Of course this will mean opening everything up and major surgery. Haven't been up for it yet - maybe over the Thanksgiving or Christmas holidays I'll give it a whirl.

Nice stuff you got there. The Stephens absolutely love tubes.
 
My bad, there is L pads on the back of the cabs for HF response.
Don't need a paper towel tube to check these horn drivers, crisp and clean.
Sound fantastic with a quad 6v6 push pull VOM console pull.
 
Back
Top Bottom