Matt.C

subwoofer auto-powering on issues

hi,

i have a yamaha sw215 subwoofer connected to a (uk spec) yamaha rx-v450, with speakers obviously but they arent relevant to my problem.

ive read through the manual that comes with the subwoofer about making the unit automatically turn on when needed. i find that sometimes the sub doesnt always power on at the start of the movie. at the moment its set up as as follows..

on the rx-v450:
all speakers = 'small'
bass out = 'swfr'
crossover freq = '80hz' (anything below this freq is sent to the subwoofer)
swfr = '+5db' (everything else on 0db)

on the sw215:
high cut-off dial = '80hz' (anything above this freq is ignored)
volume/gain dial set to '40%' (this shouldnt make a difference at all)

i tested it by leaving the subwoofer in standby, powering up the dvd and avr and selecting 'play movie' as soon as i could.

the times are from the moment i clicked on play movie to the time (according to the time display on the dvd) when the sub clicked on, sound levels for these tests stayed constant on both avr and swfr using the default sound track (dd 5.1):

swat (r2) - 1:05 (during bank shootout when the guy fires his ak)
black hawk down (r2) - 0:00 (during the dolby digital intro)
rush hour 2 (r1 rce) - 0:00 (on the very first infinifilm intro before any other menus appeared)
charlies angels 2 (r1 rce) - 0:27 (on the flame effect straight after the push-in past the columbia tristar lady)
fast and the furious (r1) - 0:23 (as soon as the music started after universal logo had disappeared)
the rock (r1 critereon) - 1:18 (when the words 'the rock' appeared onto the screen w/explosion)
bad boys 2 (r4) - 1:02 (establishing shot of the 'smuggling coffins')
matrix reloaded (r4) - 0:00 (dolby digital intro)

any suggestions? other than 'get up and manually turn it on!' will be appreciated..
thanks.

ScottCHI

leave it on all the time

"All men are frauds. The only difference between them is that some admit it. I myself deny it."

Steve Lumbert

It appears that it is working normally. The auto turn-on on my subs work the same way. Basically, they won't turn on until LFE frequencies are fed to them. In your case, only when they are 80Hz or lower.

The only thing I find annoying about the auto turn-on feature is that on some movies with little/no bass, they go to sleep and come on during the middle of the movie.

ScottCHI

just leave it ON all the time

"All men are frauds. The only difference between them is that some admit it. I myself deny it."

Dave Poehlman

Turn this knob all the way up. Your receiver is already handling the rolloff so.. there's no reason to do it twice. Besides, depending on the slope of your rolloff you might be missing out on a sliver of frequencies.

For the sub to turn on automatically, it needs to receive some sort of bass signal above a certain level. It depends on the amp but usually it doesn't take much to get it to switch on.

One way to make your sub "more sensitive" to bass signals is to turn up the "SWFR" volume on your receiver and decrease your volume knob on the sub amp an equivalent amount. This sends a stronger signal to the sub, but since you've turned the sub down, it doesn't sound any louder. This way the sub will be more likely to trip when sound is present because the signal sent to it will be louder.

It looks like you've done that a little bit already (+5 dB). In my HT, for example, I watch movies at low levels at times and my sub wasn't alway kicking over either... so, I turned my output up to +10 dB and now it works fine.

Ted Lee

i think scott wants us to .... leave it on all the time....

fwiw, that's what i do as well. it's just easier that way.

this is my dvd collection. there are many like it, but this is my own ...

Wayne A. Pflughaupt

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Matt.C

turning the level up on the reciever and down on the sub seems to work good and the sub kicks in usually by the dvd menu if not sooner.

thanks for the help.

ScottCHI

although that is a solution, it's not the best solution in terms of sound quality. it "dirties" the sub signal sent from your receiver and you end up using less of the sub's amplifier to reproduce the sound. net result = less clean sound from your sub.

just leave your subwoofer on all the time.

"All men are frauds. The only difference between them is that some admit it. I myself deny it."

Greg*go

I agree with the others about turning up the juice on the receiver, and it appears you do as well. Another option is to plug the subwoofer into the swithed outlet in the back of the receiver. This keeps the sub on whenever the receiver is on. And that's when I usually use the sub, so it works out well for me.

I certainly don't expect anyone to remember me 65 years after I die, but you wouldn't know that from the way I act.
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