^^
1) if there's a sub present, MCACC will detect it by sending a test tone over the sub 1/2 outputs, which btw are Y'd together - there is only 1 true sub/LFE output with 2 jacks. if the subs produce the test tone then it will set sub to Yes. there's nothing you the user have to do, running Auto MCACC. you can try manually setting sub to Yes, but from your posts I think you've tried that.
2) the fact that you got hum from the sub amp then nothing is not a good sign, IMO. you may have a
shorted or defective cable going to the amp or a wonky Y connector. hopefully, its as simple as that. but it's also possible the amp blew with the paralleled sub drivers. connecting speakers together or bridging amps incorrectly is a recipe for presenting too low of an impedance to the amp. parallel cuts the impedance in half, series adds the impedance. connecting your subs together in parallel is a very bad idea, especially to save running an extra speaker wire.
I looked at Jamo website and didn't find a true passive sub, I did find one that's part passive & part active but assuming it's a true passive sub, next...
3) hum can be a ground loop, not uncommon with subs, and you solve it by putting a cheap calrad isolation transformer on the sub cable before it enters the sub (sub amp) I have never used a passive sub so can't speak to anything specific to your Jamo gear. usually, tho, sub amps with l/r inputs have them for line level connections or speaker level connections but if only 1 needs to be used, some just have you connect to the left jack. since the sub LFE output is "mono" not stereo subs (1 sub for each front sprkr & using line level connections), you'd really only need the 1 connection.
I found a manual for their 201 sub amp & snipped a page with the connections for passive subs
2-10-2013 2-46-56 PM.jpg 144k .jpg file
I also found this by doing a search on jamo amps -
http://www.whathifi.com/forum/home-cinema/how-to-connect-jamo-sub-to-amp
this may be for their conventional subs but it's more info for you.
I assume this is how you connected it?
if so, you didn't need to add any Y cable to the PIoneer sub out, since sub 1 & 2 are internally already connected. you could connect both sub 1 and sub 2 to the left & right amp line inputs with their own cables, set the amp to low pass, and set the low pass crossover to the highest setting, 150hz for this model.
for that matter, you really don't need to use 2 sub inputs at all if you select the mono setting on the amp! since the sub LFE output from the Pioneer is mono'd already, you really only need 1 connection from the Pioneer to the amp. the only reason for 2 is if you were using line level connections to peal off the bass freq's from the front preamp outs, and then send the rest to the fronts. hardly anybody does that with a typical HR receiver & speaker setups.
connect the passive subs the way it's shown in the diagram for bridged amp mode with 2 speaker wires, each with its own red & black, to each sub (I guess you can say that's 4 wires total, but speaker wiring has the red & black in 1 "cable" so I consider that 2 total) unless I'm missing something, I have no idea what you are mean or had in mind for 4 cables!
keep in mind that bridging now renders this as a 8 ohm minimum load amp. if your passive subs are lower than 8 ohm rating, then you're asking for trouble. from this page, and your description, you should
not have tried wiring the passive subs in parallel!! just follow this diagram if it's your amp. by connecting the subs' 2 "voice coils" in parallel, you may have or could damage the amp from halving the impedance to 4 ohms or less, when the bridged amp is only supposed to see an 8 ohm load!
4) can you plug the jamo amp into something else to try it? any kind of receiver?
5) you were given
correct advice on the crossover by another poster. you use ONLY the one in the receiver if you connect a sub to the receiver's sub LFE outputs. doubling the crossovers will result in a gap in the bass frequencies the sub reproduces. All sub companies I know of instruct the user that using a LFE output, you bypass the sub's internal crossover by turning it OFF or setting it to its highest freq.
6) out of phase... having MCACC detect every one of your speakers that way is kind of unusual. but if they are wired correctly, ignore the message. you have the mic in a proper, at least reasonable position, and while I wouldn't stand next to it myself, I don't think that would cause a problem, just not be as accurate. keep the mic aimed directly at the ceiling, preferably on a tripod on the sweet spot, or put it on the seat back but not in the seat itself where butt is

it may be your specific B& W speakers or the way speakers interact with the room.
Quote:
Originally Posted by
Dobes49 
the sub amp has a right and left input, so I came out of Sub 1 on the SC-55 with a Y and passed the signal along to the sub amp split in two because I had a high quality double RCA cable. I input it to the right and left channel of the sub amp and then set the sub amp to Bridge, assuming that each channel would get the same signal. Rather than wire the two voice coils in series, I suppose I could have run a four wire cable to my sub speaker, but that would require re-fishing another two wire through to it I figure. The fact that there seems to be no output from the sub is puzzling - possibly a simple fix of changing a receiver setting?
no simple receiver setting I know of, if you already tried setting sub to Yes in Manual MCACC & the Pioneer crossover to 80 Hz as a starting point. your ceiling speakers may require a higher crossover, look at their specs and use their lowest rated bass as a guide - if it's 100hz, then you'll need to set the crossover for all your speakers to 100hz.
your wiring doesn't seem a conventional or optimum hookup. if you wired the 2 sub drivers together to avoid running another set of speaker wiring, that's not a great idea.
my advise is take out all that caca and get back to a basic 1 RCA cable hookup
with another known good cable, un-bridge the amps and connect to only ONE sub voice coil. then try it. you can add the 2nd sub driver once you get a known basic setup that works.
I think you may need to re-think what you're doing plus re-read the MCACC section in the Pioneer manual. the Phase Control button you mentioned has nothing to do with the out of phase MCACC "error". the Phase Control feature changes the group delays from each speaker so that sound from all the drivers arrives at listening position at same time, hence "in phase". the manual describes this so I think you're just randomly trying things because you haven't figured out how the receiver works yet. and if you re-read the MCACC chapters, you'll know that the Pioneer has NO button for reversing phase, or any setting in the setup to do that & you'll learn what Phase Control is about

sorry, not being critical but it's clear that you're new to Pioneer & if I were in your shoes I'd be re-reading the 2 chapters on using MCACC and probably your Jamo sub, too

it's also possible the receiver is defective. unfortunately, you have too many issues going on & I can't tell if it's the setup, wiring, damaged sub amp, defective receiver. if it's still within the 30 day window, I'd consider returning it for a new one just to see if it's the receiver or something else in your setup - even if it costs you more. or I'd just get one of the new models, say the SC-65 or SC-67 and be done with it. they aren't that much different than the SC-55 but its possible your "good deal" is a lemon!
now I've spent > 1 hr on this reply looking up stuff for you on a product I've never used nor would use

but unless you have a bad cable (possible), the Y connector isn't making good contact (possible), blew the amp (possible), blew the sub preamp output on the receiver, or receiver was defective (possible) you most likely have something weird in your setup.
I have used MCACC for 10 years, and it's never failed to detect my subs. there was no magic setting I had to do, it just worked in Auto MCACC. the only times I lost output to the subs was with a cable I have that very occasionally shorted out in one connector.
Edited by ss9001 - 2/10/13 at 2:27pm