Author Topic: Extraneous 1/4" jack on F-2B??! (Read 127 times)

newuser · « **on:** August 24, 2008, 11:23:08 AM »

Won a combo on ebay, prize is F-2B #901894 which has an extra 1/4" jack on the back panel

I asked the seller to ask former owner: "...he said it was a spare input or output." was the reply. Ok. Looks like an output to me, but I have no clue why or how to use it. There are two wires soldered to one of the terminals of the mono (M) jack and connected to one of the terminals of the extraneous jack. Any one have any idea what's up with that? Here's what it looks like from the inside:

I've never seen the inside of an F-2B before so I don't really know what's going on here. Using the factory jacks it works as the product info and FAQ would indicate. Thus I assume the two wires to the strange jack are the only changes. Can anyone verify that? I'm not about to plug anything into that strange jack till I know more about it.

Gratuitous Bass shot

Thanks in advance, -dan

willgunn · « **Reply #1 on:** August 24, 2008, 01:20:14 PM »

It looks like the previous owner of your F-2B added a second Mono Out jack (wired in parallel with the factory one). Most likely, that person wanted to drive BOTH channels of the pictured BGW power amp with a mono signal. If my memory serves me well, that BGW doesn't have any built-in switching allowing the user to parallel the INPUTS of both channels into both OUTPUT stages simultaneously - a feature that many newer pro power amps possess as standard equipment (I owned that same model BGW 30 years ago...and used it with an F-2B AND a Series II, no less!). As it is, the same thing could have been accomplished simply using a Y cord!

David Houck · « **Reply #2 on:** August 24, 2008, 05:22:35 PM »

Thanks Will !!

Oh, and nice gratuitous bass shot Dan!!

newuser · « **Reply #3 on:** August 25, 2008, 01:07:19 PM »

Will thank you very much for explaining that!!!! The combo came w. a 1/4"male to RCA plug, a RCA female jack on a 3pin cable (one mono out to BGW 3-pin input), so I guess they used an regular 1/4" cable for the other channel. Indeed, much simpler to use a "Y" cord! Dave, thank you for the photo compliment! Got a digital camera and have been having fun at the expense of musicians and backyard birds! Had not heard of BGW amps till the auction, was always a Crown user. I've long since moved my Crown D-150A over to home stereo use but back in the 80's my rig used to be a Furman PQ-3 to a Yamaha SPX90 to the Crown in bridged mono. Cab was a Community Light and Sound PBL!!!

Same cab w. a DS5 copy into an Acoustic Image Focus 2R III (just a great little amp!!!!), @ the Clinton Music Fest 8/23/08. Also have a Schroder 1212L and imagine I will get another for the big rig, they sound ok and really cut (miss my Acme Low 2B for quiet stuff though).

The bass @ a recent rehearsal.

dfung60 · « **Reply #4 on:** August 25, 2008, 06:34:37 PM »

newuser -

Beautiful bass... But you don't actually put it on your amp like that do you? It gives me the willies just looking at the picture! I know if I turned my back to it for a microsecond, I'd be hearing oops!.

David Fung

terryc · « **Reply #5 on:** August 26, 2008, 01:42:31 AM »

I second that david and god knows what that carrying handle will be doing to the finish on the back!!!
One damn nice nice bass. Use a stand please!!!!!!

newuser · « **Reply #6 on:** August 26, 2008, 06:47:39 AM »

Good points and thanks folks. Angle of shot is deceptive, much less precarious than it looks, shot was strictly posed (color a little off, redish, due to flash), amp belongs to the rehearsal studio (hourly rates, very convenient), no I would never leave any instrument perched like that for longer than it takes to shoot the pic, thanks though!!!

-dan

mica · « **Reply #7 on:** August 27, 2008, 12:32:34 PM »

Hi Dan,

It appears to be an added mono jack. You can't use the added jack by itself. If you are using only one mono (mixed) output, then use the factory original one.

Have fun!