I have a Pioneer VSX-35TX receiver when connected to the subwoofer there is no sound questions on what I am doing wrong.

http://www.martinlogan.com/pdf/manuals/manual_descent_i.pdf

Are you sure the correct input is selected on BOTH the TV AND the A/V receiver?

Does the subwoofer work on other inputs? If not, is the subwoofer connected correctly? If so, is the input connected correctly?

These receivers have a history of having broken connections on the subwoofer jack. Would have to go in for repairs.

I own 2 of these Pioneer VSX-D903S units.

The only way to hook a powered subwoofer up to a VSX-D903S is if your subwoofer is equipped with amplified/speaker level terminals on the back, in addition to the line-level input. If you only have a line-level input, do not attempt to hook it up to this receiver.

If you're lucky, and have speaker-level inputs on your powered subwoofer, you would use the amplified terminals (connect to B-channel on the receiver). DO NOT connect anything to the line-level connection.

Alternatively, you could build two unpowered subwoofers, then set the receiver's Impedance switch to LOW, then connect one enclosure to each of the "B-channel" outputs. Connect your regular left and right speakers to their corresponding "A-channel" outputs. [Impedance range: 4 Ohm minimum, 16 Ohm Maximum]

Hello
Try to download the user manual to Pioneer VSX & THX user manual. click here to down load the same. You will get details of it connections from the manual.
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It would seem the TV/SAT source is where the problem lies. No picture with CD? Really?

How about bypassing the receiver to prove what is failing?

Hi there, the Pioneer VSX-815 amplifier only feeds out a mono LINE LEVEL output with the subwoofer signal. Therefore you would need to connect the SUB PREOUT jack at the rear of the unit to the "line level input" on a self-powered subwoofer. Hope this helps.. Cheers, Yusuf

I have problem with connecting subwoofer to receiver.

The original Pioneer subwoofer has its own amplifier built in to the speaker, so the only cable required on the original speaker is a single RCA cable. To connect a different brand subwoofer to the Pioneer you will have to make sure that you have a subwoofer with the same specs. It will need its own built in amp to work, as you can only connect it with one RCA

It's probably going to need output transistors and some resistors, it's a job for a technician. A rough estimate on price is $100 to $130 (that's parts and labor). Before the smoke it may have only needed repair of bad connections.