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pinkoboe
01-09-2004, 02:16 PM
Lo all :]

Can anyone point me the direction of guide as to how best setup a sub for use in a HT setup? Purchased a Rel Quake today to compliment my B&W's but I'm not entirely sure that it's calibrated correctly.

I have the following controls on the sub: contour (either set to depth or slam), roll-off, mode and lo-level. The manual makes reference to phase, crossover and gain which I'll admit is slightly confusing me.

For example: "Adjust the crossover to a point where the sub and the speaker are sure to share frequencies (B, 3 for big speakers or C, 4 for smaller speakers" If anyone could explain that, it would be greatly appreciated :]

Cheers in advance.

Nick.

Jimmy C
01-09-2004, 03:15 PM
regarding sub integration once I bought my new speakers. I have a REL Strata III that WAS paired with Paradigm's Studio 60s, now it is mated with the Revel M20s. With the Studios, blending was a no-brainer - I couldn't see what all the fuss was about regarding the integration issue. Once I brought home the Revels, I thought I was in trouble... integration was definitely not so cut and dry. My dealer's reasoning was it is easier to integrate a sub to a speaker that has some bloat in the midbass... not sure if this is true, but the Paradigms were far easier to blend.

Another recommendation was to set x-over on the sub w-a-y down - his reasoning was LF info actually "leaks" out above the set frequency... following his train of thought, I get GREAT results. For instance, my speakers go down to around 45 cycles according to Revel (certainly seems like more!)... I have the the sub set at B-2 (circa 36 cycles, IIRC) without bass bloat fogging up the room. LF is now very fluid and just enhances the aural picture, especially on thin, bass-lite CDs. In all honesty, I do not need it all the time, but you are doing HT - a different animal.

Still, I would worry about the music first... better (according to REL, and I agree) use a lower x-over setting and possibly more output. I didn't realize HOW low I needed to go - your results will obviously vary, but this is a good starting point, IMO. The phase switch makes the sub's sound wave propagate at different times, hopefully aligning with the mains (if the sub is at a different distance from the listener, for eg.) Personally, I don't hear to much of a difference, regardless of setting, in my room. Still, once the sub is set up, sit in "the" chair, have a buddy flick the switch - the loudest position is supposed to be better, according to REL.

I'm using the REL-supplied, hi-level, Neutric plug - not sure if that matters any.

Ultimately, there is no replacement for experimentation in YOUR room, with YOUR gear... fear not, it's fun!

Hhmmm... what exactly is "REL" an acyronyn for, anyway?

pinkoboe
01-09-2004, 11:17 PM
Cheers for the responce :]

"my speakers go down to around 45 cycles according to Revel (certainly seems like more!)... I have the the sub set at B-2"

When you say you have your sub set at B-2, what exactly does that mean? As I mentioned in my original post, it makes reference to this in the manual, but leaves me very confused.

Thanks again :]

Nick.

Jimmy C
01-10-2004, 05:11 AM
O.K., the lettering (A,B,C,D) is the coarse adjustment, while the numerals (1 through 6 in my case, and hopefully yours) are the fine adjustment. For eg., my "B2" is actually 34 cycles, "B3" is 36, etc. ... this is the rolloff point, the point where the bass stops, if you will.

REL recommends you start at "A1", turn up the coarse adjustment (lettering) until it sounds bloated, then back it down to the last position - for instance, maybe "C" was too high a rolloff, back it down to "B", after that, turn up the fine adjustment (numerals) until you get what you want.

I'm tempted to use the phrase "x-over"... it's not... it's "rolloff". REL likes to have the main speakers do their thing and have their "sub bass system" just fill in the very bottom.

I'm not sure your "coarse and fine" are calibrated like mine, but since it's 4 degrees outside and I have nothing to do, here goes: A1 is 22 cycles, A2:23, A3:25, A4:27, A5:28, A6:30, B1:32, B2:34, B3:36, B4:38, B5:41, B6:43, C1:46, C2:49, C3:53, C4:56, C5:60, C6:64, D1:69, D2:73, D3:78, D4:83, D5:89, D6:95. You're going to have to experiment.

Hope this helps a bit more...

Mash
01-12-2004, 06:43 PM
There are several CD's with frequency sweeps available (Stereophile sells two) typically at $20. These come with frequency sweeps, and reference tones between 500 and 1000 Hz, that you compare to obtain a smooth frequency response "at your listening position".

First, kill the subwoofer and run the test tones to learn the low frequency where your main speakers run out of gas. Let's say it is (really) 40 Hz.

Then turn on the sub with minimal volume and set the sub cross-over at 60 Hz [or 1/2 octave above the 40 Hz]. Turn the sub volume up until you just start to notice it. Then run through the frequency sweeps repeatedly and tweak the sub volume until the sub is 'mostly' balanced to the main speakers.

If you hear a slight 'hump' at the selected cross-over when the rest of the sub's sweep frequencies are mostly balanced to the main speakers, then slightly lower the sub cross-over frequency. If you hear a slight 'suckout' at the selected cross-over when the rest of the sub's sweep frequencies are mostly balanced to the main speakers, then slightly raise the sub cross-over frequency.

When the sweeps seem fairly uniform in sound level, put away the CD with frequency sweeps and listen to some music. After a week, repeat the sweep frequencies again and determine if you need to tweak something. You may have to play with the sweep CD several times.

Woochifer
01-12-2004, 08:32 PM
Those instructions apply more to systems that connect the subwoofer to a two-channel system and either run the main speaker cables through the subwoofer's crossover before outputing to the main speakers or have the preamp output go through the subwoofer crossover and back to the amplifier.

Otherwise, if you're connecting your subwoofer to a home theatre receiver, then you'll need to use the receiver's bass management functions, rather than the crossover on the receiver.

All you need to do is:
1) go into the speaker setup on your receiver and set all of the speakers to "Small"
2) connect the receiver to the subwoofer using the subwoofer preout
3) turn the crossover frequency on the subwoofer all the way up
4) set the level (gain) on the subwoofer so that it matches the level on the mains. To do this you're best off getting a SPL meter over at Radio Shack and using a test tone to match the levels.

The phase switch, you just use the position that gives you the most even sounding bass. That's all!

Now, if you have boomy sounding bass, then it get a bit more complicated. But, cross that bridge after you've set up your subwoofer and enjoyed it for a few good bounces.

Willow
01-13-2004, 05:31 AM
Those instructions apply more to systems that connect the subwoofer to a two-channel system and either run the main speaker cables through the subwoofer's crossover before outputing to the main speakers or have the preamp output go through the subwoofer crossover and back to the amplifier.

Otherwise, if you're connecting your subwoofer to a home theatre receiver, then you'll need to use the receiver's bass management functions, rather than the crossover on the receiver.

All you need to do is:
1) go into the speaker setup on your receiver and set all of the speakers to "Small"
2) connect the receiver to the subwoofer using the subwoofer preout
3) turn the crossover frequency on the subwoofer all the way up
4) set the level (gain) on the subwoofer so that it matches the level on the mains. To do this you're best off getting a SPL meter over at Radio Shack and using a test tone to match the levels.

The phase switch, you just use the position that gives you the most even sounding bass. That's all!

Now, if you have boomy sounding bass, then it get a bit more complicated. But, cross that bridge after you've set up your subwoofer and enjoyed it for a few good bounces.

Woochifer....when you say turn it all the way up ( the x-over ) are you saying it should be say if you sub has x-over 50hz and 180hz by up do you mean 50 or 180

cadolfan
01-21-2004, 08:51 PM
Those instructions apply more to systems that connect the subwoofer to a two-channel system and either run the main speaker cables through the subwoofer's crossover before outputing to the main speakers or have the preamp output go through the subwoofer crossover and back to the amplifier.

Otherwise, if you're connecting your subwoofer to a home theatre receiver, then you'll need to use the receiver's bass management functions, rather than the crossover on the receiver.

All you need to do is:
1) go into the speaker setup on your receiver and set all of the speakers to "Small"
2) connect the receiver to the subwoofer using the subwoofer preout
3) turn the crossover frequency on the subwoofer all the way up
4) set the level (gain) on the subwoofer so that it matches the level on the mains. To do this you're best off getting a SPL meter over at Radio Shack and using a test tone to match the levels.

The phase switch, you just use the position that gives you the most even sounding bass. That's all!

Now, if you have boomy sounding bass, then it get a bit more complicated. But, cross that bridge after you've set up your subwoofer and enjoyed it for a few good bounces.

i need help with this. I've got a Sony Sub hooked up to h/k avr325. what is crossover frequency? Is that where the sub takes over the bass the center and other speakers can't take? i turned the knob on the back of the sub to approx 120hz. I also have the phase switched to normal. Is that right? Also in the front of the sub theres a leve knob. How high do I turn this up to? The h/k comes with an spl meter built into the remote. It ask you to turn the volume up to -15db and run the spl meter. i have all the speakers set to small. I think I read somewhere on this board that someone ran a test with a regular spl and their h/k built in spl and they were pretty close.

Woochifer
01-22-2004, 11:41 AM
Woochifer....when you say turn it all the way up ( the x-over ) are you saying it should be say if you sub has x-over 50hz and 180hz by up do you mean 50 or 180

turn it up to 180 Hz or bypass it altogether if your subwoofer allows for that. Do this ONLY if your receiver is handling the bass management.

Woochifer
01-22-2004, 11:44 AM
i need help with this. I've got a Sony Sub hooked up to h/k avr325. what is crossover frequency? Is that where the sub takes over the bass the center and other speakers can't take? i turned the knob on the back of the sub to approx 120hz. I also have the phase switched to normal. Is that right? Also in the front of the sub theres a leve knob. How high do I turn this up to? The h/k comes with an spl meter built into the remote. It ask you to turn the volume up to -15db and run the spl meter. i have all the speakers set to small. I think I read somewhere on this board that someone ran a test with a regular spl and their h/k built in spl and they were pretty close.

The crossover frequency indeed is where the subwoofer takes over from the other speakers. However, like I said, if you're using the "Subwoofer Out" output from your receiver, then you should just set your speakers to small, and turn the crossover frequency to the highest possible frequency (or bypass it if you can) letting your receiver handle all the bass management chores.

cadolfan
01-22-2004, 12:04 PM
The crossover frequency indeed is where the subwoofer takes over from the other speakers. However, like I said, if you're using the "Subwoofer Out" output from your receiver, then you should just set your speakers to small, and turn the crossover frequency to the highest possible frequency (or bypass it if you can) letting your receiver handle all the bass management chores.

So I should set the frequency higher than 120hz's on the sub. I think it goes to 200hz's. I wasn't sure becuase on the sub manual it says based on the size of the speakers determines where to set the frequency. For me it is 120hz's but according to you I should set it to 200hz's. But it also sounds like i should bypass it if i can. How is this done. Still need my question answered on where to set volume level on sub.