1937-38 Acoustic Clarifiers - Printable Version
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1937-38 Acoustic Clarifiers - Gene Pederson - 07-14-2013
Are the clarifiers used in the 1937-116 & 690 the same as the ones in the 1938-116 & 690?? can they be swapped ?
Thanks,
Gene
RE: 1937-38 Acoustic Clarifiers - Ron Ramirez - 07-14-2013
Yes. Same size, same appearance, made the same as far as I can tell.
RE: 1937-38 Acoustic Clarifiers - Gene Pederson - 07-14-2013
Thank You, Ron!!
Gene
RE: 1937-38 Acoustic Clarifiers - Arran - 07-14-2013
I know that if I were running Philco I would have used the same design of clarifier from 1936-38, there wouldn't be any point in changing them without a valid reason.
Regards
Arran
RE: 1937-38 Acoustic Clarifiers - morzh - 07-14-2013
I fail to see the reason of making tens of new models every year and discontinuing the previous ones....they did it all the time.
RE: 1937-38 Acoustic Clarifiers - Arran - 07-14-2013
They did that to some degree but mostly they just facelifted existing models and made some technical mods. The Philco 60 and 89 were examples of this, the changes were mostly on the cosmetic side such as cabinets.
Regards
Arran
RE: 1937-38 Acoustic Clarifiers - audiomagnate - 07-15-2013
On the subject of Acoustic Clarifiers... how the H**l do they work? I've actually spent some time examining the patent, but to me they seem to be passive radiators in a a non sealed (that's an understatement!) box, which seems absurd.
RE: 1937-38 Acoustic Clarifiers - Chuck Schwark - 07-15-2013
They are passive resonators, that help dampen out cabinet sympathetic vibrations.
Ron can correct me if I'm wrong, but many of those high-end cabinet did have backs.
Chuck
RE: 1937-38 Acoustic Clarifiers - Ron Ramirez - 07-15-2013
OK Chuck
The 1936 and 1937 Philco models with clarifiers (116X, 116PX, 680X, 37-116X, 37-690X) did not have backs. Philco used ventilated backs on the 1938 models (38-690, 38-116 plus several lower end consoles without the High Fidelity circuitry and with no clarifiers). Even in the 1938 models, the woofer chamber was not sealed.
RE: 1937-38 Acoustic Clarifiers - morzh - 07-15-2013
You do not necessarily have to have back for it to work. Often times the radio was against the wall, so the wall and the narrow space between the radio served as the lossy load, so clarifiers could use that. But even without back the very presense of an anti-resonator tuned to the resonant frequency of the cabinet/speaker system helps somewhat.
RE: 1937-38 Acoustic Clarifiers - audiomagnate - 07-15-2013
Interesting. Has anyone actually done an A/B test to see if they're actually doing anything?
RE: 1937-38 Acoustic Clarifiers - PhilcoJohn - 07-15-2013
When I have my 38-116 Playing, It sounds better if it is put up against a wall. The bass is much more present. Do not know if the clarifiers do anything. I think it was a gimick Philco came up with to compete with RCA as RCA used the sound tubes in their sets.. Just my thinking.........what do you guys say?
RE: 1937-38 Acoustic Clarifiers - Mondial - 07-15-2013
My feeling is that they do work. The Philco patent filed for the clarifiers shows a bass response curve of the cabinet with and without the clarifiers. Without them there is a pronounced peak at the cabinet resonant frequency, while with them the peak is reduced by about 10 dB.
The clarifiers are actually tuned damping diaphragms, which absorb and dissipate energy at their self resonant frequencies.
Here is a link to the actual patent:
https://patentimages.storage.googleapis.com/08/da/cd/c19e3c21599213/US2059929.pdf
RE: 1937-38 Acoustic Clarifiers - Chuck Schwark - 07-15-2013
Ah, yes. The "bass reflex effect" with a console up against the wall.
Forgot about that. D'oh!
I'm properly chastised....
Chuck
