Bass Sucks

[David Gaudreau]

I hooked up both of my Supercube subs and seems like the only spot where the sub sounds good is everywere but where I sit. How do I fix this?

Using AVR-3608 and denon DVD-2910 two Supercube referance subs

 

[Sheep]

I hooked up both of my Supercube subs and seems like the only spot where the sub sounds good is everywere but where I sit. How do I fix this?

Using AVR-3608 and denon DVD-2910 two Supercube referance subs

Put your subs where you sit, and crawl around the room until you find a spot that gives you that same bass you like. Then put the subwoofers there.

If you have room, you could try nearfield placement, IE, put the subs right by your listening position.

Also, try adjusting the Phase.

SheepStar

 

[sploo]

Put your subs where you sit, and crawl around the room until you find a spot that gives you that same bass you like. Then put the subwoofers there.

Good info there from Sheep.

What's basically happening is that you're getting room/speaker interaction problems. It happens, to different degrees, in every room.

If you were to walk around your room with a mic or SPL meter, monitoring different bass frequencies, you'd see peaks (boom) and nulls (no bass) all over the place. Oh, and different frequencies will have peaks and nulls in different places.

Try what Sheep has recommended. You could/should also try for a seating position that's 38% of the length of your room. I.e. if your room was 100ft long (I can dream anyway) then you'd want to sit 38ft from the front wall - this tends to have the best response for your room. The worst place to sit is usually halfway between two opposing walls (i.e in the middle).

If you want to spend some time reading up about this, then you could try F. Alton Everest's "Master Handbook of Acoustics", or for useful articles, and products to combat room acoustic issues, look at http://www.realtraps.com.

 

[Glenn Kuras]

Yes all great advise, but bass traps are really going to be the best bang for the buck.. Focus traps in all corners of the room.. You will be amazed at the sound quality you will get.. Sub location is important also..

Glenn

 

[bpape]

Plan on doing both. First of all, try the Harman recommendation of centering the subs on 2 opposite walls - front and rear or left and right - either will work.

Then, once you get the response smoothed out, you can begin to damp the ringing with treatments.

Also, not to be overly simplistic, but have you considered moving the seat? It really could be that you're just sitting in a bad place.

 

[rollinrocker]

David

where are your subs placed? I also use two reference subs in my setup.

 

[Buckeyefan 1]

Also consider stacking the subs. It sounds like they are cancelling each other out. Two subs can be a nightmare to mesh. To test, disconnect one, and see if that helps. If it does, you have location issues.

 

[AudioSeer]

Also consider stacking the subs. It sounds like they are cancelling each other out. Two subs can be a nightmare to mesh. To test, disconnect one, and see if that helps. If it does, you have location issues.

I agree with this. If you have two subs and split them, they are going to cancel themselves out at a certain frequency. That frequency depends on how far they are seperated.

One single powerful sub (or two subs stacked) set in the corner along with parametric equalization is the way to go IMO.

 

[jeffsg4mac]

I agree with this. If you have two subs and split them, they are going to cancel themselves out at a certain frequency. That frequency depends on how far they are seperated.

One single powerful sub (or two subs stacked) set in the corner along with parametric equalization is the way to go IMO.

No, for most rooms that is not the way to go. Two subs solve many issues. Examine these charts and you will get a better idea. Look at the last chart, a single point in the corner is the worst place for a sub in a standard room. Two subs in opposite corners will be the best compromise for most rooms. That's how I have it and I have pretty even bass from all the listening positions.

http://www.audioholics.com/techtips/setup/loudspeakers/SubwooferplacementP16.php

 

[AudioSeer]

No, for most rooms that is not the way to go. Two subs solve many issues. Examine these charts and you will get a better idea. Look at the last chart, a single point in the corner is the worst place for a sub in a standard room. Two subs in opposite corners will be the best compromise for most rooms.

That's an interesting article - thanks for posting it.

However, aren't these graphs completely room and listening position dependent? I don't know how much they will translate over to other people's listening environment.

For example, the frequency curve of my room with one sub in the corner looks completely different.

The theory, as I understand it, is corner placement excites all room modes equally therefore avoiding notches. Then you EQ the peaks out.

 

[jeffsg4mac]

For example, the frequency curve of my room with one sub in the corner looks completely different.

I guess my first question is, what did you use to determine what your room response was? and how do you know it is accurate?

Of course not all rooms are exact, those charts are based on mathmatical calculations. There are lots of factors to consider, but they are a starting point. From my experiences so far they have been pretty darn accurate.

 

[AudioSeer]

I guess my first question is, what did you use to determine what your room response was? and how do you know it is accurate?

I used a SPL meter playing a track with a 16 to 200 hz sweep. It's quite obvious where the curves are even by ear in my room because the modes add about 12 db. Off of the top of my head, the response in the room that has my 2 channel system was about the same at 25 and 80 hz with two 12+ db peaks around 45 and 65 hz.

There's also the notching issue with use of two subs. I believe that one of your charts show this.

Also, the charts make an assumption on listening position. Bass response varies by a large margin as you move around the room. I guess you never know until you test...

 

[jeffsg4mac]

If you want a better picture of what's going on in your room then use some tones and plot them on a graph, however, the most accurate way is to use an RTA. The way you used will really only show you that you are not flat, but not what your actual response is and exactly where and how much the peaks are. Once you achieve a flatter response with your sub or subs, you won't believe the difference it makes in the overall sound.

 

[Glenn Kuras]

If you want a better picture of what's going on in your room then use some tones and plot them on a graph, however, the most accurate way is to use an RTA. The way you used will really only show you that you are not flat, but not what your actual response is and exactly where and how much the peaks are. Once you achieve a flatter response with your sub or subs, you won't believe the difference it makes in the overall sound.

Actually there is another program called ETF.. I think there sight is www.eftacoustics.com or www.eftacoustic.com... YOu can shoot the room in about 5 seconds which is nice when you are trying out different things.. They do have a free dowload..

Glenn

 

[westcott]

Two subs usually sound better in opposing parts of a room as jeffg suggested. Two side walls, centrally located or the front and the back of the room, centered on the walls.

Diagonal opposition may also work.

Corner placement is rarely necessary or suggested since most people do not have the luxury of placing speakers far enough away from the walls to reduce bass reinforcement or sit in the opposing corner to benefit from this placement. It also makes for a very uneven frequency response across most rectangular rooms of average to small size.

Using an 80Hz crossover setting, a distance of 21" to the back wall from the sub is considered a good starting point.

Bass is an acquired taste but once you get it tuned in right, it can be a very rewarding experience.