Subwoofers

[dazoy]

Ive recently moved to a new apartment and have been toying with subwoofer placement etc.

Till recently I had subwoofer near front left speaker, but with the new apartment, the usual front left position also opens up to open open dining area and the kitchen. I suspected the subwoofer would have to run hot and annoy neighbors, and decided to move it closer to the main listening position.

After a couple of days of lifting/moving the big lump of subwoofer around the living room, I found that behind the couch seems to work really well. The room correction software (Audessey) has evened out a lot of peaks and valleys and there is enough low bass with no boomy-ness.

What have other's experiences been like with subwoofer placement? Any particular position that works well?

On a side note - Should we not have a sub forum under Audio Components for Subwoofers now?

 

[efernand1]

As far as I know and experienced at different places.....Subwoofers (Sealed / Ported) depends on placement and also the acoustics of the room....this room can be a dedicated room or juts the living room / hall which most of us have our systems.....

Audyssey plays a good role in setup but to get the best from the subwoofer, we need to tweak phase control settings, placement at different spots...sometimes subwoofer crawl etc.....

As for me, my place does not really need a 12 inch sub, the only reason I am using it is because of the SQ and how low it can go........yet it does vibrate a lot of stuff for certain movie scenes and fast music....but i like it....I have placed it right under the center speaker...supposed gives a good experience for movies....

Each one would have a different placement and preferences of SQ. Ultimate idea is to reduce boominess and deliver the actual low bass which the front speakers cant deliver.....and also the punch wow factor!

 

[yellowcurrypaco]

As far as I know and experienced at different places.....Subwoofers (Sealed / Ported) depends on placement and also the acoustics of the room....this room can be a dedicated room or juts the living room / hall which most of us have our systems.....

Audyssey plays a good role in setup but to get the best from the subwoofer, we need to tweak phase control settings, placement at different spots...sometimes subwoofer crawl etc.....

As for me, my place does not really need a 12 inch sub, the only reason I am using it is because of the SQ and how low it can go........yet it does vibrate a lot of stuff for certain movie scenes and fast music....but i like it....I have placed it right under the center speaker...supposed gives a good experience for movies....

Each one would have a different placement and preferences of SQ. Ultimate idea is to reduce boominess and deliver the actual low bass which the front speakers cant deliver.....and also the punch wow factor!

Off topic but could help me decide or suggest on which way to go.
I'm planning to use a 12" driver for my DIY sub and I've attached 2 images of the SPL of sealed and vented design simulation. The vented SPL has 2 graphs for 2 different volumes, with a 4db boost at 30Hz. The room size is 13x18x8.5 so it's not a big room and maybe it'll provide enough boost even when going with a sealed sub?
The vented obviously goes lower but its 90 L and the construction is a little more complex.

Vented SPL


Sealed SPL with 2 different Volumes

 

[efernand1]

If you are more into movies....vented subs make more sense.......for music sealed subs....

placement is the ultimate deciding factor, I use a BIC PL 200 which is vented.......rear ported. I tried for 3 months clogging the port to see the performance. I did enjoy it for music and movies to some extent......placing the sub again in another place in the room is not an option for me and hence removed the clog from the port, tweaked some freq of bass cut off on the AVR and it serves my purpose for both.

 

[arunlouie]

If you are more into movies....vented subs make more sense.......for music sealed subs....

placement is the ultimate deciding factor, I use a BIC PL 200 which is vented.......rear ported. I tried for 3 months clogging the port to see the performance. I did enjoy it for music and movies to some extent......placing the sub again in another place in the room is not an option for me and hence removed the clog from the port, tweaked some freq of bass cut off on the AVR and it serves my purpose for both.

Is it fine to close the port on this sub? I heard it might damage the driver. Is it so?

 

[efernand1]

If you are careful and a conservative listener, you can try stunts...(experiments)....I did....carefully.....

 

[Bhoot]

While I don’t want to shake down any norms, I’d say that a lot of conventional and broad wisdom is used to answer the questions. I’ll explain
Ported vs sealed. Conventional knowledge says ported for movies sealed for music, while it may really be correct for a lot of applications, if you’re going for a subwoofer from half decent manufacturer, this knowledge is out. The SVS PB2000 and SB2000 are good enough for all movies, whereas a klipsch sw10 (ported) is bad for movies, whereas it is pretty good for music. Let me explain.
Ported or sealed Each subwoofer can only go low to one frequency maintaining the dB/SPL. Once you go lower than that frequency the dB/SPL falls you lose sound and hence the sense of bass. You can introduce room modes to kinda make it extend lower, but then from 40Hz drop you might hit about 36hz if you’re lucky.
Subwoofer Crawl. Again everyone swears by it and a lot of people get on to all 4s and start searching for the perfect spot. It is simple physics, and anyone with slight knowledge on the subject will tell you, the only way to get a perfect sub response is to knock down those 4 walls and ceiling to get the best response. Diving a bit deeper into the tech used for subwoofer crawl. We use a audio clip which continuously plays one frequency, eg 40Hz from MLP to where you’ve crawled to. Now I want you to play a 50Hz clip and you’ll realize the perfect position would have changed, even if by a few inches. Your subwoofer has to go from minimum from 20-80 and changing positions is impossible during an action sequence.
Room resonance and standing waves. Again, you can’t defeat physics. You’ll need to calculate the subwoofer related to your room and then realize what faults your sub and room has. Ofcourse treatments are possible but in rooms less than 1500cuft they are almost going to not help you.
REW and DSP. This is the approach I followed. Having purchased a couple of RYTHMIK FVX12 and watching a couple of movies, the vibrations made the theater come alive, a few hours later, a headache ensued. It was because of the LFE, the brain is also vibrating (it’s not a belief but a fact) and gets fatigued. Watching Transformers Last knight or Overlord will prove my point. Finally I bought a dsp and a usb mic from a reputed brand and started taking measurements. My subwoofers were getting extra (too much) help from the room and the SPL below 30Hz was unbelievable. Till now the sub I owned were pretty shitty and never went so low to make me realize this. Finally I’d like to state my largest filter of -dB on the DSP is around 22 Hz with a 5q -15db.
going a little deeper on the subject I’d also like to correct another conventional knowledge on flat frequency responses. They are also wrong because of the concept of room mode and perception of volume. Our ears are not mics and 20Hz 200Hz and 2000Hz might indicate same reading on the mic but will sound very different in volume on ears.
My intent of this post isn’t to offend or insult anyone, it’s just an eye opener so that people know exactly what they are buying so they don’t feel cheated later.