: JVC RX-7042s subwoofer problems, help


OneDown
2004-07-06, 10:42 AM
i just got my first home theatre system. the problem is with my Velodyne CHT-8 sub.

i bought a simple phono plug y-cable to connect my to my sub-out line. i tried plugging into the line level input and then the line level output to get it to work but i got nothing. i go to turn on the sub on the amp but it says there's no sub.

i figure i have to attach both sets from the sub at the same time. will this solve my problem? i would buy two set of y-adapters to plug into each ends of of the y-cable i have now and then plug into the R and L output and the R and L input. could this be a solution?

also, would i be better off buying a "subwoofer cable" or am i good just sticking with the simple RCA phono cable i have now?

thanks for any info anyone can provide.

57
2004-07-06, 12:08 PM
Most subs only require one cable - read the manual that comes with the sub to find out. You may wish to try without the Y-adaptor.

If you've got a long run, an inexpensive cable may not pass the signal. You may need a better cable. Perhaps you could buy one from a store that allows returns and return it if it doesn't solve the issue.

Also, first you could try to move the sub close to the receiver and try a short cable?

OneDown
2004-07-06, 12:20 PM
first thing i did was check if i could plug in with only one cable but nope, my sub doesn't work that way. it would probably be easier to get one that would but the other i was looking at, the Athena PS300 isn't as good as the one i got and it's the same price.

in any case, it's not a long run. the sub's 6' to the amp.

RNAChemist
2004-07-06, 03:21 PM
make sure on your receiver to turn on the sub.

JVC receivers have an option of turning on/off the sub within one of their hiden menus.

On the front panel of your receiver where all the speaker indicator lights are, look for the sub light...if its illuminated then you are fine at that end, if not turn it on within the hiden menu.

I_Want_My_HDTV
2004-07-07, 09:25 AM
The only reason to get a subwoofer cable is to improve the bass or if you get noise or hum from the subwoofer with a cheap cable.

Connect the subwoofer to the subwoofer out on the A/V receiver. Set the bandpass to the highest frequency or use the LFE (direct, bypass) in connection at the sub. If there is no LFE in, use a Y-adapter at the sub if you want. It should not be necessary but it may help with some subs if the line level is low.

Set the subwoofer volume to about 1/2. The "no sub" is a setting on the receiver. Use the arrow keys (or whatever the manual says) to change the setting to "yes" or "on". Save the setting. That should activate the subwoofer out line. Try playing some material.

To set the level, adjust the bass so that it sounds about the same (just a little fuller) with the sub on as off. This is your reference point. You probably want to add a little more bass, especially for movies. If your receiver generates white noise, a sound meter is a very good way to set sound levels for all your speakers.

If the sub has a phase control, try having someone adjust it while you listen some material with full bass or use a sound meter with a bass tone. You might just want to leave the phase at 0 if you have trouble adjusting it.

OneDown
2004-07-09, 09:20 AM
I managed to get it working out the sub out and it sounds decent. my thing now is with the LFE.

my amp has a button on the front, from which you should be able to turn your sub on or off. when i push it, it always says there's no sub. if, however, i go through my speaker menus i can switch it on from there. so in theory that's all good.

i have a display that shows all the channels that are playing at any given time. when i throw in a dvd in 'LFE' lights up but there's no box around it, indicating the channel isn't being used. beside that indicator though it says 'subwoofer' with a box around it, meaning that's working at least.

am i missing something from the dedicated LFE channel? or would it make no difference from my current set up?

RNAChemist
2004-07-09, 01:00 PM
sounds like your amp is working fine.

The subwoofer box lights up, with box around it indicating the subwoofer has been set to "yes".

The LFE indicator lights up when LFE effects have been detected (on a DVD for example). No box around this indicator even though it lights up.

Note: the boxes only light up for speakers that are detected.

OneDown
2004-07-09, 02:07 PM
that's my point though. with the boxes indicating speakers that are detected, shouldn't the LFE be detected becuase that is basically my subwoofer (or the channel that is sent to the sub)?

i've been looking into this more and could it be because my DVD player is using a digital coaxial linear pcm output? should i instead get a dvd player capable of usign digital surround (ac-3)? like plug using an optical cable then set the dvd player to use DD.