How to hook JL F112 sub to both preamp and pre/pro

texas, are you sure you can't connect both a 2 channel preamp and a HT pre/pro to a fathom sub simultaneously? i was running this setup for a while (on the advice of JL Audio) without any issues. RCA from the HT pre/pro; XLR from the 2 channel preamp. XOver in the HT Processor was set higher than that in the sub. worked great.

texas, sorry to belabor the point, but i'm very curious on your position where multiple sources to the fathom subs are concerned. if you're still following this thread, would you mind expounding on the circumstances that would result in competing signals? i'm genuinely curious about this, as i ran this way with an F112 without any (perceived) ill-effects for a while after consulting with the tech at JL Audio. am i setting myself up for some issues down the road??

Jeffkad, yes, my preamp (aesthetix calypso) has multiple outputs. i ran the main L/R outs from the HT pre/pro into a bypass input on the preamp, and from there, one set of outs to my main amp, a second set of outs to the fathom sub. additionally, i ran the subwoofer out from the HT pre/pro to the second inputs on the fathom. i made sure the XOver point in the pre/pro was set higher than on the fathom and everything seemed to be fine. Do not get too hung up on finding a preamp with HT Bypass, as any preamp will do, you’ll just have to remember to run the volume up when you select the input from your HT pre/pro.

best to call JL Audio and speak to their tech (Barry) about your specific system. i've also talked with the tech at SVS and they suggested the same setup the JL did, noting no damage would occur.

Another option you might consider are Rythmik subs. they are FANTASTIC and their DI amp option (soon to be replaced by the PEQ3) is specifically designed to work with both a 2-channel preamp and a HT pre/pro.

to your comment on high end pre/pros, my aesthetix calypso was night and day better than my theta casablanca. to my surprise, using my Wyred4Sound DAC2 as a preamp was also better than the casablanca and very close to the aesthetix.

texas,
that's really odd that the manual is SO explicit on this point, while their technician is clearly telling end users something different. point taken, thanks for your comments - perhaps the OP should bring this up with JL.

Jeff,
my rig isn't the final word in high end, but i've spent the last several years going through several different amps, preamps, sources, DACs, speakers, etc to get to a point now where i'm comfortable evaluating gear IN MY ROOM to MY PREDILECTIONS. those are important to note, as we all listen for different things, and my gear might sound dramatically different in another room.

i'm currently running Wilson speakers and VAC monoblock amps. the aforementioned DAC2 serves as DAC and preamp and is surprisingly capable in that role. that piece was really something of a surprise, as i never expected it to better my Weiss Minerva, and certainly never thought I'd be running it as a preamp.