Bass you can feel

[Wheatenterrier]

So I recently got a new PC 12 plus from SVS. It's awesome.

So what range of frequencies are the most easily felt? When I watch movies I feel small vibrations from my listening position. I want to do everything I can to increase the bass that I feel.

The reason I ask is in my room with current placement I have a huge hole in the frequency response from about 40-50hrz. Everything else is there from 15-80 though.

So far I've found that positoning it closer to the listening position seems to help me feel more. I realize that I'll never get the effect of one of those shakers but want to get as close as I can without one.

I figure that certain frequencies are probably easier to to feel than others. If I know which ones they are I can work on placement.

 

[jamie2112]

Do you have a corner you could load the sub into?

 

[lhard77]

I agree with Jamie, I have had a lot of luck putting the sub in a corner. I can really feel it!!

 

[Wheatenterrier]

I tried the sub in the corner at the end of my room http://jamisonandalicia.blogspot.com/2008/12/basement-pics.html
and got a similar response to this, but it's so far away, and sounded less detailed.

 

[croseiv]

Feeling bass is a combination of SPL and frequency. Generally you will feel more than hear frequencies below 30 Hz. But having more drivers and output capability will help you "feel" the bass from 30 Hz and up. SPL is a function of moving air, and you need drivers to do that. You may need a second sub...But you do have a pretty large null around 45 Hz that will take away some impact that can be corrected with EQ.

 

[jamie2112]

Sounds like you need one of these:http://www.zzounds.com/item--BEHDCX2496

 

[Wheatenterrier]

Sounds like you need one of these:http://www.zzounds.com/item--BEHDCX2496

Do you have one of those? I'm sure it would help me reduce some peaks, but can it boost that low area?

Also I'll add a couple pics of the room to the blog, to give yall a better idea of the crappy room I'm dealing with. The funny thing is I built the room and designed everything, but didn't know what I was doing. If I had it to do again I would have aranged the viewing position very differently or put the quasi home theater in a smaller purpose specific room.

 

[Wheatenterrier]

Look how fast I am. J/K. New photo's taken and up loaded. now have a look at the room.
http://jamisonandalicia.blogspot.com/2008/12/basement-pics.html

 

[Jeff R.]

My opinion would be that your room is huge, you may need another sub. I agree with Croseiv.

 

[Pyrrho]

Do you have one of those? I'm sure it would help me reduce some peaks, but can it boost that low area?

Also I'll add a couple pics of the room to the blog, to give yall a better idea of the crappy room I'm dealing with. The funny thing is I built the room and designed everything, but didn't know what I was doing. If I had it to do again I would have aranged the viewing position very differently or put the quasi home theater in a smaller purpose specific room.

Normally, trying to boost an extreme dip will overtax the amp and subwoofer giving you more distortion. This is because, to get a 3 dB increase, you need to double the power. To get a 6 dB increase, it will be 4 times the power, and an 8 dB increase will be 8 times the power. If I am reading your graph correctly, you have about a 20 dB dip near 45 Hz, which would take 100 times the normal power to boost up to the right level. You are not going to be able to EQ that and boost the amp to muscle your way out of that problem.

You have a placement and/or room problem, and your best bet is to try a different location for your subwoofer. A second subwoofer might help with the problem, but you really should try all possible locations first with the one you have. Try every corner that is possible, and try the middle of every wall that is possible. If you find it easier to do it this way, put the subwoofer in your listening position, and measure the response at various places in the room. Then, put the subwoofer in the spot that measured best, and then measure again from your listening position.

Most likely, you will never get it perfect, so you must simply select the location that is better than the other options. You can EQ away peaks, and EQ very slight valleys, but you cannot EQ deep valleys in your response, unless you have such an amazing subwoofer that it can put out many times the normal level that you need. In this case, it seems, it would need to be about 100 times better than at its normal level for about 45 Hz, and that would take an incredible subwoofer to do.

 

[WmAx]

The main 'slam' feeling from bass would probably be the range that correlates with the resonant frequency of the human chest area, which would be centered somewhere in the 70-100Hz range, if memory serves. This would indicate you need subwoofers covering a rather broad frequency range, and higher than usual, in order to give you maximum 'feeling' of 'slam'. However, most subs are not optimized to play that high, due to compromised construction choices which you can correct by adding in proper absorption materials into the cabinet. But another problem is that using a subwoofer to such high frequencies is going to cause substantial integration problems with the main channels in most cases. To correct this would require dual subs, one placed in each side of the room. You should also use a much more capable/flexible crossover as compared to what is in your receiver. The Behringer DCX2496 is the ideal tool for systems that have the objective of having the highest quality blending of mains and sub(s). It is also a very powerful EQ. You must run the mains and sub(s) through the DCX, which would require your receiver to have pre-outs and would require you to use an outboard amplifier for the mains.

Note: some people like Mike C. will use separate midbass subs that are specifically optimized to reproduce a range such as 80-130 Hz in order to effect maximum possible 'slam' effects, as most main channels will not have the ability to produce distortion free dynamics in this band at high amplitudes. To handle this band well, one needs mains with say 2 x 6.5" or 7" midbasses of good quality per cabinet, and they would need the bandwidth restricted to 70-80Hz and over in order to maximize their ability. Allowing full range response to these driver over-taxes the drivers and increases distortion.

-Chris

 

[bandphan]

Thats the reason i added a second sub and indepedent eq/crossover to adderss room issues.

 

[just-some-guy]

O/P. did you try placing the sub right behind the couch ? i would try that.

 

[Wheatenterrier]

O/P. did you try placing the sub right behind the couch ? i would try that.

Very good Eye! I did try that spot and guess what, a much flatter repsonse. I would probably only be able to use that position when my wife is out of town though. I tried behind the couch in against that wall.

So what do yall do with your sub cable when placing the sub in different positions? Is there a wireless device that can be used to send the signal to the sub, do we have the technology yet?


Wmax, thanks for anwsering my original question. I have heard people talk of that slam feeling in the chest before but never felt it. You even offered advice on how to produce the effect all be it expensive and complicated to me.
Would you say that this is different from the vibrations type of feeling you get during movies? Becuase I read about people saying the feel shaking/vibrating from LFE effects and these are what I really want to amplify.

 

[WmAx]

Wmax, thanks for anwsering my original question. I have heard people talk of that slam feeling in the chest before but never felt it. You even offered advice on how to produce the effect all be it expensive and complicated to me.
Would you say that this is different from the vibrations type of feeling you get during movies? Becuase I read about people saying the feel shaking/vibrating from LFE effects and these are what I really want to amplify.

It is a collective effect. The very low LF combined with the upper bass. Of course, many F/X are a combination of low and high bass, such as explosions and especially gun shots. You will feel the gun shots pound you with a very capable midbass response. Of course, you also need to ensure your response at listening position does not have a large null in the midbass band.

-Chris

 

[just-some-guy]

how about building a stub(for lack of a better word) wall ? between the sub and that window. build a wall about 2-3' out and about 1' above the sub. this will focus the sound towards the listener.

i built a 4' x 8' wall to do just that.

 

[Wheatenterrier]

how about building a stub(for lack of a better word) wall ? between the sub and that window. build a wall about 2-3' out and about 1' above the sub. this will focus the sound towards the listener.

i built a 4' x 8' wall to do just that.

That would prolly help. I'm done building walls though. If there was a way to put the sub behind the couch agains the wall and hide the cable running to the sub I might be able to get away with putting it there.

I going to put it back there and watch a movie and see what I think. I have already measured the reponse from there with the roomEQ software and it looked good. If I get what I'm looking for, then I may prepare for a battle with the wife about that position.

 

[Adam]

Is there a wireless device that can be used to send the signal to the sub, do we have the technology yet?

Yep! There's more than one, but a member here recently bought and wrote about SoundCast's new SubCast system. The thread he made after getting it is linked here.

EDIT: You still need to run the power lines, though - for both the sub and the SubCast.

 

[ParadigmDawg]

I hate to be the one who says it but your mains may be part of the issue here. I doubt they have the headroom needed in a room as big as yours and lack that punch in the 60-80hz range.

 

[croseiv]

I hate to be the one who says it but your mains may be part of the issue here. I doubt they have the headroom needed in a room as big as yours and lack that punch in the 60-80hz range.

Very good point there PD!