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Username: newuser

Post Number: 45
Registered: 12-2004
Posted on Sunday, August 24, 2008 - 11:23 am:   Edit Post

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

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:

inside pic 1

Strange jack

all 4

mono jack wiring

Any ideas?

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 family shot

Gratuitous Bass shot ;)

Thanks in advance,

Username: willgunn

Post Number: 19
Registered: 2-2007
Posted on Sunday, August 24, 2008 - 1:20 pm:   Edit Post

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!
Username: davehouck

Post Number: 6951
Registered: 5-2002
Posted on Sunday, August 24, 2008 - 5:22 pm:   Edit Post

Thanks Will !!

Oh, and nice gratuitous bass shot Dan!!
Username: newuser

Post Number: 46
Registered: 12-2004
Posted on Monday, August 25, 2008 - 1:07 pm:   Edit Post

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!!!

Community PBL w DS5 clone + AI Focus 2R III

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).

Another nice bass shot

The bass @ a recent rehearsal.
Advanced Member
Username: dfung60

Post Number: 357
Registered: 5-2002
Posted on Monday, August 25, 2008 - 6:34 pm:   Edit Post

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
Senior Member
Username: terryc

Post Number: 570
Registered: 11-2004
Posted on Tuesday, August 26, 2008 - 1:42 am:   Edit Post

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!!!!!!
Username: newuser

Post Number: 47
Registered: 12-2004
Posted on Tuesday, August 26, 2008 - 6:47 am:   Edit Post

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!!!

Username: mica

Post Number: 5486
Registered: 6-2000
Posted on Wednesday, August 27, 2008 - 12:32 pm:   Edit Post

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!

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