Fosgate 101A Decoder - "ALTERNATE" switch

[kfbkfb]

https://worldradiohistory.com/Archi...eo/80s/HiFi-Stereo-Review-1983-10.pdf#page=34^^^
ALTERNATE setting, it can change the system's
operating time constants to give better re-
sults with some imperfect program sources.


Is there a list of SQ encoded content that benefits from being played back with this switch at "ALTERNATE"?


Kirk Bayne

 

[par4ken]

https://worldradiohistory.com/Archi...eo/80s/HiFi-Stereo-Review-1983-10.pdf#page=34^^^
ALTERNATE setting, it can change the system's
operating time constants to give better re-
sults with some imperfect program sources.


Is there a list of SQ encoded content that benefits from being played back with this switch at "ALTERNATE"?


Kirk Bayne

Jim Fosgates interface circuit was said to be faster than that of the Audionics unit. Perhaps it was too fast causing artifacts/anomalies with some material necessitating the alternate setting. It also has a mono switch so that you can get output from the rear with mono sources. The Composer has a separation potentiometer, the use of which will accomplish both goals instead.

I doubt that anyone would have made such a list but perhaps 101A users could chime in?

 

[sjcorne]

I've tried flipping it on my 101A, the effect is subtle but it seems to slightly reduce the front-to-back seperation in order to mask the 'pumping' in the rear channels.

 

[Sonik Wiz]

Jim Fosgates interface circuit was said to be faster than that of the Audionics unit. Perhaps it was too fast causing artifacts/anomalies with some material necessitating the alternate setting. It also has a mono switch so that you can get output from the rear with mono sources. The Composer has a separation potentiometer, the use of which will accomplish both goals instead.

I doubt that anyone would have made such a list but perhaps 101A users could chime in?

About all I can say is it made no audible difference to me used either way. As pumping is mentioned frequently about SQ Logic decoders but rarely about Tate DES, I think proper balance in either approach is essential for masking this. If a quad mix is not as prominent in the rear as a listener might want, than raising the rear levels sorta improves this but now some pumping might be heard. Any decoding artifacts of this nature requires proper balance to mask it.