So what the heck is it? It's an all-tube single-channel graphic equalizer, made by Blonder-Tongue Laboratories in 1959. This is the front of the "spec sheet" I got along with the thing. The address given is "Newark 2, New Jersey", so zip codes did not yet exist. The controls for each band are little wheels, the edges of which stick out along the bottom; these are connected to upright plastic cylinders which are centered behind a vertical slot for each band of the frequency spectrum. Each cylinder has a spiral red stripe on it like a barber pole, so that when the wheel is rotated, the stripe shows as a red spot moving up and down in the slot... hence a "graphic" equalizer using rotary controls! Note the picture of a piano keyboard along the top, lining up with the frequency bands (one per octave). When I saw this thing I said, I must own this.
So how does it sound? I'm not sure, the thing looks too amazing to actually use. But when I checked, I found that all the frequency bands were in the wrong places, sometimes drastically, leaving gaping holes in the frequency response. (Warning: tech talk, watch out...) I traced out the circuit and found that it was a series of bandpass filters, each one using half of a 12AX7 tube, with the center frequency tuned by an RC network. Here's where my capacitance meter came in handy: I found that the capacitors in these RC networks had drifted in value over the years, some by more than 50% from what was printed on 'em! So my rainy day science project last summer was replacing these caps with the correct values, and testing and tweaking, and now the thing specs out better than the day it was made (probably). When you set it "flat", you get flat. It seems to work fine, but ya know what? It's STILL too hilarious looking to use. I mean, what am I gonna say to my clients? "Hey, wait, let me try the BLONDER-TONGUE AUDIO BATON on that guitar sound!" Heck, I don't know, it might actually sound as cool as it looks... I must try it.
10/98 UPDATE: Witness the power of the web! Somewhere in New Jersey, a semi-retired gentleman named Ben Tongue was surfing the web, and came upon this very page. Contact was initiated, and he kindly sent me not only a copy of the original owner's manual, but also the schematics, the patent application for the circuit, and a copy of a review in "Audio" magazine from 1959! The company he started is now in the business of making hi-tech equipment having something to do with TV. I'll scan some of his stuff and add it here soon. My sincere and heartfelt thanks go out to Mr. Tongue.
Well I finally scanned some stuff, by popular demand. These are links right to the graphic files, which are rather large but may survive downloading and printing. Enjoy!
Spec Sheet [42K]
A review from "Audio" Magazine Feb. 1959 [100K]
Schematic Diagram (sorry this isn't a better quality scan) [156K]
Interesting promo photo of the Baton in use [84K]
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