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690XX and 690X
#1

Hi,

Here's another nomenclature curiosity as a follow on to the recent De Luxe thread concerning the 37-690X.

Both the 1937 and 1938 model 690 designations have an X trailing the model number, generally understood to mean that the model features that Philco staple, the Inclined Sounding Board (ISB). The 1938 model, with its inclined control panel, earns a Double-X.

But, while recently cleaning and detailing my 690 X and XX models (something that's been long overdue!), I realized that, measure, poke, probe, inspect as I may, I can find no inclination to the sounding board on either model. Nor, that I can tell, are any of the speaker drivers inclined behind the sounding board. So what gives?

One might surmise that perhaps they planned to embody this feature, only to remove it prior to final production. But surely not on both the 1937 and 1938 models. One could also argue that they simply continued to use the ISB X nomenclature on the 690s, even with 0 degree angle of inclination to vertical, because of its favorable association with Philco tone quality by the public, fostered by years of advertising.

One has to admit that over time the angle of the ISB inclination was reduced (compare the 112X with the 116XX, for example) and that with the introduction of sound diffusing cabinets and, on the 690XX/X high-frequency speakers, the need for it was surely diminished, if not, in truth, eliminated. The original intent of the ISB was to direct medium and high frequency sounds upwards instead of beaming them out along the floor and on the early models, with single large speaker units, it likely did what they claimed. But with the advent of diffusors and multiple radiators the need for it all but vanished (how many modern speaker cabinets have inclined baffles?). 

So was the X in the 690s just a marketing ploy? Or is there inclination in there somewhere that I'm missing?

Paul
#2

I think you're right - I think it was just a marketing ploy.

--
Ron Ramirez
Ferdinand IN
#3

"X", as in extra sale jargon.

Agree with Ron.

Chuck
#4

Hi,

Yes, I think that about sums it up. 

They must have decided that the ISB brought no or very little benefit to the 690 models, because of sound diffusors and their use of high-frequency (actually what we'd call mid-range today) speakers that ameliorated beaming. On top of that the ISB must have complicated cabinet design, adding to cost - unnecessarily in these cases. But were they to drop the X it would appear to potential buyers that something was missing. So it seems they just kept it going with the X and XX.

They were not taking anything away from the set's performance, so the customer did not truly lose out.

Paul




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