Locating bass <80Hz?

[olds1959special]

I have four subwoofers in my bedroom! LCR and rear! I can definitely feel where the bass is coming from.

 

[pablolie]

I have four subwoofers in my bedroom! LCR and rear! I can definitely feel where the bass is coming from.

Is that desirable? Would you set up 4 speakers to listen to stereo? Seems pretty disorienting and seems to destroy any intended staging on top, at least so it seems to me?

 

[olds1959special]

Is that desirable? Would you set up 4 speakers to listen to stereo? Seems pretty disorienting and seems to destroy any intended staging on top,mat least so it seems to me?

Most of the sound comes from the front L/R, which I am the closest too. I don't feel like I'm missing any stereo imaging. The rear setup just plays the ambience recovery channel.

 

[pablolie]

Most of the sound comes from the front L/R, which I am the closest too. I don't feel like I'm missing any stereo imaging.

... which might mean you need 4 subs in your room to defeat weird bass artifacts and directionally...? Then again I am not sure which frequency we are defining as "bass" here...

 

[olds1959special]

... which might mean you need 4 subs in your room to defeat weird bass artifacts and directionally...? Then again I am not sure which frequency we are defining as "bass" here...

My subs are set at 80 Hz LPF, but there is a 12" sub for L/R and a 10" for C (and 10" for rear.) I can still tell where the bass is coming from.

 

[Mnyb]

I'm stil not convinced that one can differentiate between locating your subs or locating signals <80Hz in a practical home setting with imperfect subs and imperfect filters and imperfect room ( infinite slope filter no distorsion or other extra sounds ) .

But I'm all ears to hear about your practical solutions to make it work for you apparently some have success with one sub some need a swarm of them .

 

[olds1959special]

I'm stil not convinced that one can differentiate between locating your subs or locating signals <80Hz in a practical home setting with imperfect subs and imperfect filters and imperfect room ( infinite slope filter no distorsion or other extra sounds ) .

But I'm all ears to hear about your practical solutions to make it work for you apparently some have success with one sub some need a swarm of them .

In my other setup I have two speakers and no sub, but they are full-range including a 10" radiator. It's just different, less auditory envelopment, but a very pure stereo experience.

 

[Keith_W]

I'm stil not convinced that one can differentiate between locating your subs or locating signals <80Hz in a practical home setting with imperfect subs and imperfect filters and imperfect room ( infinite slope filter no distorsion or other extra sounds ) .

I have a multichannel DSP controlled system where each driver has its own DAC/amp channel. When I am testing channel assignments in REW, I play pink noise through channels 1-8 to make sure that everything is wired correctly. Guess what, I can tell which subwoofer is playing the pink noise <50Hz from listening alone. No need to walk up to the subwoofer and touch the cone. There is something going on here, experts say one thing but my own experience is another!

 

[simon-b]

To be honest even when we played with REL sub's at ELAC/TDL in the 80's (We where both on the same trading estate) we had to turn the subs crossover down to stop it interfering with the main speakers. A sub is a sub and I only ever use it for the bottom octaves up to 40hz. So the sub sound doesn't have any direction. I also stick to downward firing as it makes no difference as its for the sub bass. I did notice the gap under the sub is about the same as the TV cabinet. So the sub bass propagates under the unit. 12" driver sealed 60 litre capacity. Makes the settee shake when needed.

 

[pablolie]

My subs are set at 80 Hz LPF, but there is a 12" sub for L/R and a 10" for C (and 10" for rear.) I can still tell where the bass is coming from.

From everywhere, it seems.

 

[levimax]

But I'm all ears to hear about your practical solutions to make it work for you apparently some have success with one sub some need a swarm of them .

So far I have had the best luck with either one sub co-located and equal distance from the mains to 2 subs co-located with the mains. I have also tried 4 subs and 6 subs but prefer one or two subs. While there is some truth to the recommendation that the location of the sub(s) away from the mains and or multiple subs gives "the most even in room FR response" I find the advantages of co-location (easier/better time alignment, more flexibility for a higher crossover point, better/ more consistent imaging, ability to use Linear Phase Crossovers) to more than offset the slightly more uneven FR response. YMMV.

 

[ChrisG]

Just a small note here: I gave up on the Genelec setup and went back to my previous system:
Speakers - 2x Seas H152-08 + 1x 18Sound NSD1095N. The bottom woofer is lowpassed around 300Hz, and the upper woofer runs up to around 950Hz to meet the compression driver.
Amp - QSC USA-850. Around 400w/ch of old PA iron. I'm sure better amps are available, but this one just keeps on trucking.


The Genelec 8030s will be moved from entertainment to mixing duties, but I'm not sure what to do about the sub. Perhaps I should sell the set and purchase a pair of 8340s or something...

 

[Sokel]

Another factor we often forget is that an x-over point is not curved in rock, specially when setting levels after it.
A 80Hz x-over point for example will end up way higher (depending on the slope of course) if we set some considerable gain at lows (subs, bass, whatever) .

So unless we exactly measure and see after the setup we always have to calculate beforehand.

 

[Sokel]

Another factor we often forget is that an x-over point is not curved in rock, specially when setting levels after it.
A 80Hz x-over point for example will end up way higher (depending on the slope of course) if we set some considerable gain at lows (subs, bass, whatever) .

So unless we exactly measure and see after the setup we always have to calculate beforehand.

..as an example, here is where a L-R24dB, 240Hz x-over end-ups with only +2dB gain at lows.

A whooping 254Hz!

 

[JaapD]

In cases where the front (radiating part) of the subwoofer is placed more than about 1,1 meter (3,5 ft) from the front- and/or side wall you may encounter audible differences. Why? Because of quarter wave cancellations.

 

[Oddball]

If you can't locate your bass means you messed it up. Bass is supposed to be directional unless the multi-channel mix is way off. There will be clues in other channels that will lead you to a direction of bass even with advanced systems like Dirac ART.

In stereo, well, if you can't tell if bass is more to the left or right you do have a huge problem . Time to get another preamp and do things right.

 

[pablolie]

If you can't locate your bass means you messed it up...

That is not universally accurate, it entirely depends on what your goal was to begin with. There are test tones to check on stereo image, and if the outcome is clean, it means you did things correctly.

 

[Oddball]

That is not universally accurate, it entirely depends on what your goal was to begin with. There are test tones to check on stereo image, and if the outcome is clean, it means you did things correctly.

There is no such thing as universally accurate. But I think you got my point...Hope others will as this is really tiring thread.

 

[Miniyouuuu]

subs should generate a uniform bass all around the space, but obviously respect the channels signal.
If bass is located behind you or on one side only, soundstage will be affected.
My Lintons go down to 40hz in room. They have enough presence, I just need supplementary bass below 60hz where bass directionality is less recognizable. Setting the crossover higher than 80/100hz will create bass overlapping and directionality issues.

 

[pablolie]

The problem in these discussions is there's a lot of overlap between extrapolating what's worked for us individually into universal design validity.
We all know "bass" can be tricky in real world rooms. Hopefully that's widely accepted.

After that, my only point is to get bass test tracks that are granular enough to establish what kind of imbalance is or isn't present, and optimize from there.