06-27-2016, 11:53 AM
Wouldn't be in a terrific rush to replace the spkr. As you may know the spkrs for the 20,21,70, and 90 (all the same style) suffer with arthritis (stiff paper cones and spiders) and the fidelity is not very good. I had a 20 on the bench a couple of years ago that I disconnected the output transformer from the voice coil and connected it a modern PM spkr. I was surprised the hear how good it really sounded.
On your set It looks like it has the original output transformer, I'm thinking that any of those early spkrs will work but some are set up for push/pull output tubes (two tube instead of one). The difference being the output transformer. The P/P spkrs will also have 4 wire where yours has3. If you find a 4 wire one you can change the output transformer to your old one and your all set.
Terry
On your set It looks like it has the original output transformer, I'm thinking that any of those early spkrs will work but some are set up for push/pull output tubes (two tube instead of one). The difference being the output transformer. The P/P spkrs will also have 4 wire where yours has3. If you find a 4 wire one you can change the output transformer to your old one and your all set.
Terry
