Speaker/Subwoofer Integration Tips for Best Bass Performance

[gene]

Is your subwoofer properly integrated into YOUR A/V system? A great subwoofer can sound, in a word, "great", but a properly integrated subwoofer can help your entire system sound great. This article will talk about two settings that can make or break that process: bass management and the distance setting. Failure to get these adjustments right can adversely impact the sound quality of your home theater and its ability to reproduce the rumbles in action sequences of blockbuster movies.

Let us show you how to ensure you get the BIGGEST WOW effect!

Read: Subwoofer Integration: Bass Management and Distance Settings Explained

 

[shadyJ]

Nice article Steve, but I always thought of the sub as a linebacker rather then the QB! QB = center speaker; a central player that gets all the attention, but it is nothing without a good team. A good home theater is a team effort from all components!

 

[GarryP]

Surprised that there are no replies to such an easy tweak, so anyhow here is my experience.

Equipment is dual SVS SB2000 subwoofers in front corners, Oppo BDP-103D, and Anthem MRX-510. Initially running ARC gave surround speakers (bipoles) a xover of 120Hz, fronts (floorstanders 160mm drivers) 60Hz, and centre (MTM 160mm drivers) 90Hz. Power amps are Rotel 120W per channel. The distances were all checked via tape measure first. Listening levels are what I would call normal ie adjusted so speech level sounds just right.

Manually changed the xovers to all being 120Hz and played some bass heavy movies such as Battle Los Angeles and Edge of Tomorrow. The subjective result was a smoother, more even bass that sounded as if it had more dynamic range. Speech also sounded clearer. I haven't the equipment to do before and after measurements so this is just my impression over the past two weeks using a variety of media - BD, CD, and DTV.

"In the case of a relatively modest bump in the crossover point from 80Hz to 120Hz, you’re still cutting driver displacement by more than half. This a huge deal: the implication is that instead of needing a pair of 5.25” woofers as seen in the aforementioned 4400 L/C/R speakers, you could get by with a single woofer assuming its power handling was up to snuff. With any given speaker, this also means that you potentially net an additional 6dB of displacement-limited output versus an 80Hz crossover frequency, as well as lower distortion at any given volume. Not too shabby for a setting that takes a second or three to switch."

Thank you for this article Audioholics, as this is something that I wouldn't have thought to try otherwise.

 

[qwsa]

Hi,Gene
Did you mention what level should we set our (Master volume) when setting each speaker level to (75dB)?
(0dB) is too loud (unbearable) for my room size? (15x12)
To use (0dB) for Master volume as Reference should one not have a minimum room size requirement for this?
My room main seating is about 10 feet away from the main speakers and the subwoofers
I have the (Master volume) set to (-10dB) when I set the speaker levels to around (+44/+45dB)
Regarding subwoofer distance, not quite sure… but I think (Auto EQ) set my subwoofers to (40 feet)

Should I leave it at that distance or take out the tape measure?

 

[aarons915]

This is a great article the only thing I would add is the importance of your speaker having a 4th order high pass to blend with the subwoofer. 99% of receivers/processors use a 2nd order high pass filter and most speakers these days are ported so they don't work correctly. So you really have 2 choices, one is to get a processor or receiver capable of a 4th order high pass filter on the mains, I use an emotiva UMC 200 to achieve this but there are other ways. The 2nd way is to bung your speaker in order to give it a natural 2nd order acoustic high pass filter which combines with a 2nd order high pass for your 4th order total high pass filter.

And to the people who think it doesn't matter much, I've confirmed with measurement equipment that the difference between 2nd order and 4th order high pass when crossing to the sub is pretty drastic, with a 2nd order high pass without the ports sealed you'll get a large dip or peak at and around the crossover frequency which won't be as seamless a blend between the mains and sub. Just my 2 cents.

 

[RF2000]

This is a great article the only thing I would add is the importance of your speaker having a 4th order high pass to blend with the subwoofer. 99% of receivers/processors use a 2nd order high pass filter and most speakers these days are ported so they don't work correctly. So you really have 2 choices, one is to get a processor or receiver capable of a 4th order high pass filter on the mains, I use an emotiva UMC 200 to achieve this but there are other ways. The 2nd way is to bung your speaker in order to give it a natural 2nd order acoustic high pass filter which combines with a 2nd order high pass for your 4th order total high pass filter.
...

I think this would only matter if your crossover point is set to where your mains are acoustically rolling off. If you are far enough above the acoustic rolloff of your speaker and you use a 2nd order high pass there shouldn't be a need for a 4th order low pass.

 

[Tea]

Just wanted to say thank you for this article. It’s amazing and solved a very old issue.

for 5 years my system had a null at the key 60-90 hz region, but as it turns out it was a phasing issue at the crossover which could be defeated using the distance controls.

Up until now I’ve used the measured physical distance, plus 90cm to account for the delay caused by my antimode sub eq. That was 5.4 meters. Following the suggestion in the article I adjusted the distance each way by 30cm at a time measuring each step. I finally settled on 6.9m and now the null has gone, the system sounds smoother AND the sub SPL is higher! Just to be clear the phasing switch alone never achieved this and made it worst.

Attached are the before and after images using an 80hz cross over (no smoothing applied) and the horizontal lines represent 10db increments. I now have work to do as the levels need re-calibrating, but it’s good to know I no longer have to put up with a null at such an important frequency.

I’ve known that distance settings were important for sound stage and speaker integration, but it never occurred to me that it could cause / solve bass nulls. This topic needs far far more attention than it’s getting