y-connect a PSW404

bsukalski

Hi, I am new to this forum and polk speakers in general (and HT for that matter
Anyway, I bought a PSW404 sub for my system. The manual says to hook the LFE channel to one of the 'Line Level' input jacks. ONE? I tried this, and could barely hear the sub!! I tried the 'Y-adapter' and hooked the LFE output to both line level inputs....and WOW....now it's like a totally different sub

I guess I should mention, I have a Denon AVR 1800...which the LFE output is unfiltered. Therefore i can use the subs crossover.
The sub volume is exactly the same as before as is the location.

My question is: Is this harming the sub by doing this? I realize that owners manuals are not always correct or clear, but the difference is way too noticable not to mention.

thanks,
brandon

bsukalski

like i said, i am new to HT...so i hope the above post makes sense? Wow, even 'Fight Club' sounds totally different with the y-cable. Maybe I read the instructions wrong?
I even have a Velodyne CHT 12 from Sound City on the way...I wish I wouldn't have ordered it now!!

chreers.:rolleyes:

John K.

Brandon, welcome. The bottom line is that feeding both sub line level inputs by using a Y-adapter can't do any harm, but shouldn't be at all necessary. As the Polk manual indicates, feeding one input should deliver enough voltage from the receiver sub out to turn on the sub(are you sure that it turned on at all with one?)and allow plenty of loudness. Feeding both will deliver voltage into both inputs which is then combined inside the sub and would give a significantly higher sub output at the same receiver sub out setting, but not the huge difference which you describe. Was one input possibly defective and did you try the other one by itself?

Another point is that you stated that the sub output of the 1800 is "unfiltered". Although I'm not familiar with the 1800, I know that other Denons of the 00 series have bass management with a fixed 80Hz crossover to the sub, and would think that the 1800 is the same. If this is the case, you should simply set all speakers "small" and connect a single RCA plug into the single LFE input on the 404, which will automatically bypass the internal sub crossover.

Willow

you may also want to set the xover as high as possible on the sub...why buy a y cable if all you have to do is turn up the sub...or buy Y and turn it down

bknauss

Although its not necessary, hooking up the line level inputs of any of the Polk subs (assuming no LFE input, or you want to use line level in) will at least yield some numerical improvements in the amount of hum, power output, and some other areas. Again, these numbers are generally pretty small and I don't know if you would be able to hear the difference, but there is at least an improvement in the numbers.

bsukalski

Hey guys, thanks for the replies!
Well, I will try the other line level input to see if one is indeed defective.

My Denon 1800 allows me to set the speaker size to large or small...but has no adjustment for the crossover level (like the newer ones do). If I hook up the reciever LFE to the single 'filtered' jack on the sub...I hear lots of audio that shouldn't be there Maybe my reciever is defective?

Willow: Yes, the x-over on the sub was all the way up. My thinking on this is (if in fact the input is not defective) that one cable with the sub cranked up would not be very good for the sub amp? With double the signal now coming to the sub, I am able to turn down the sub quite a bit...thereby reducing the load on the amp?

One more thing: I looked at the owners manual for the Velodyne (looked at the .pdf). A y-cable is necessary to hook that up to the line level inputs with my reciever. It states that one cable connected to one of the inputs will give you half the signal. And that a y-cable will deliver equal signal to both left and right inputs.
I wonder why they are different (the subs)?

Thanks again for the replies guys!!

Dr. Spec

1800 - speaks to small, sub to on/yes

404 - use LFE (unfiltered) input, which bypasses the low pass filter in the sub

Calibrate, calibrate, calibrate.