4-unit sound systems

[Kent King]

When the FM models were introduced in 1940, Scott also began offering a "4 unit" sound system. We've seen tweeter sets with the AW23 and the early Philharmonic sets (both use a Y-cable from the pedestal speaker to two tweeters). The 4-unit systems included a crossover box where you connected the bass speaker and two tweeters, and it also had a jack for an extension speaker. The crossover and 3 speakers constituted the 4-unit system, which sold for $29.50. Later units had a smaller crossover, and the smaller one came in two forms, one with a 35Z3 rectifier tube and one without (the tube socket hole usually plugged with a metal cap). 

To my knowledge (and anyone who has something, please set me straight!), we have not seen a set with the 4-unit system using the 35Z3 to drive 3 speakers. Most of the crossovers with the rectifier tube are on Laureate sets, driving the coaxial (single) tweeter mounted in the center of the large speaker. In the large purchase I made, I acquired an FM Phantom which has what appears to be an original 4-unit sound system with the FC style tweeters (see attached). Does anyone have anything similar? Any ideas on the manufacturer of the tweeters? 

Thanks!

Kent

[David C. Poland]

Karl - Kent's 15 inch flange mount speaker has the usual transformer platform bracket, but it only has the terminal strip mounted on it and a cover. No transformer.

And the speaker cable has the 5 pin small plug fitting crossover.

[Karl Sherwin]

Kent, I could be wrong but the woofer looks to be a conventional (38 ohm) speaker because it has the external connection box. In the 3 speaker systems I've seen the woofer has the high fidelity sticker on the back cover and the leads exit from that cover.

Karl

[David C. Poland]

Caution - the bass speaker for the 4 unit hi-fi system is NOT the same as the standard 12 or 15 inch.

The standard speaker has a 38 ohm voice coil. The system bass speaker is 8 ohm. The output transformers would be different too.

The Philharmonic was evidently always supplied a 15 inch standard speaker or 15 inch bass speaker for the hi-fi system. But the Phantom Deluxe and Laureate models are seen with either a 15 inch or a 12 inch speaker - I suspect depending on the cabinet selected. The FM Phantom Deluxe I mentioned above was in a large Scott radio/phono credenza cabinet.

[David C. Poland]

yes - I had a very nice FM Phantom Deluxe with Jones plugs using the crossover with rectifier. The two tweeters were open back with field coils like your photo. So each tweeter had a four pin plug (rather than 2 pin) to fit 4 pin sockets. The additional two tweeter plug pins were for the tweeter field coil. (The exact same field coil tweeter as center mounted on my Laureate's 15 inch coaxial speaker and the same crossover having 2 tweeter sockets.) I sold the FM Phantom unrestored to Steve near Dayton who is a fan of prewar FM.

Appears Scott was expecting a change over to field coil tweeters in as much as I have seen the smaller version crossover with a capped hole where the rectifier would be. 

The above FM Phantom Deluxe amp with speaker system including tweeters and crossover with rectifier, thus:

Phantom%20FM%20Deluxe%20hi-fi%20speaker%20system.JPG