Subwoofer Question.

It's been a long time since I had a subwoofer, but I got a JBL SUB 200/230 from my Brother, I gave it a lash in my mothers and was mighty surprised with the output from such a tiny box, I love ported enclosures to sealed, my last one was sealed and despite being more powerful the ported has much deeper baas.

Anyway before I took it home he had left it in my mothers for a while and I turned it in today and the baas was incredibly tight and really deep and when I take it home it sounds like crap. Boomy and the baas not nearly as deep.

I don't get it with my house ?

The only thing I can think of is the walls in my mothers are solid block internally and in my house partition. Could it be that resonance from the walls is screwing up the bass ?

This isn't the first time I noticed it either, oh and the room is smaller.

Slaphead07

Assuming you've got the settings adjusted to suit your setup, that's number 1 ..... Solid walls aren't an issue but room size can be. you're just going to have to play about with position. Is it rear ported? If so then move it in and out from a wall/corner until it sounds right. It's trial and error really.

I would assume that the walls would cause unwanted resonance and booming ?

I've tried every position, yes it's ported and I've tried every location I can. My only other assumption is that the room is just too small ?

it was the same with the sealed box.

ZENER

What source are you feeding it with ? CD Player - Laptop Audio ? If the source is low quality like a laptop then the Bass output will be . . well . . sh!te !?

What speakers are you using along with it ? Are you using the same speakers with it now as when you first heard it ? The "boominess" may be from the other speakers ?

Is there a polarity switch at the rear of the SUB ? Try flicking it ? If the Sub is out of phase with the rest of the system you will get cancellation of certain frequencies in the Subs frequency range - this is what the polarity switch is for. The effect is like having a certain range of frequencies missing - it's similar to reversing the polarity on one of your main speakers, bass gets thin and you lose the stereo image stage.

Ken

ZENER

ZENER wrote: »

What source are you feeding it with ? CD Player - Laptop Audio ? If the source is low quality like a laptop then the Bass output will be . . well . . sh!te !?

What speakers are you using along with it ? Are you using the same speakers with it now as when you first heard it ? The "boominess" may be from the other speakers ?

Is there a polarity switch at the rear of the SUB ? Try flicking it ? If the Sub is out of phase with the rest of the system you will get cancellation of certain frequencies in the Subs frequency range - this is what the polarity switch is for. The effect is like having a certain range of frequencies missing - it's similar to reversing the polarity on one of your main speakers, bass gets thin and you lose the stereo image stage.

Ken

Thanks for the reply Ken,

No polarity switch though there was on my old sub.

I fed it speaker output from the valve amp, and then plugged the mobile into the low level inputs.

The reason I plugged the phone in was to try eliminate the main speakers as the source of boominess. And to move the sub around without the main speakers on, I can't have the valve amp on without the speakers connected and it has no headphone out.

I'm still convinced it's the room itself, being small and the partition walls.

I think the boominess can be attributed to resonance at certain frequencies and you can tell this from the bass being louder at a certain frequency, probably the resonant frequency of the room itself acting like a big speaker.

It's amazing the difference it makes in my mothers, the baas is incredibly deep and a lot louder, but tighter and more controlled.

The only conclusion I can come to is that it's the room itself is just bad for baas.

ZENER

I fed it speaker output from the valve amp, and then plugged the mobile into the low level inputs.

The reason I plugged the phone in was to try eliminate the main speakers as the source of boominess. And to move the sub around without the main speakers on, I can't have the valve amp on without the speakers connected and it has no headphone out.

I'm having a little difficulty visualising this setup. Can you try a better source than a phone ? Did you plug the phone into the Low Level inputs on the Sub ? I think that's what you meant ?

Ken

ZENER

ZENER wrote: »

I'm having a little difficulty visualising this setup. Can you try a better source than a phone ? Did you plug the phone into the Low Level inputs on the Sub ? I think that's what you meant ?

Ken

Yep plugged into the low level input on sub.

I just plugged a creative sound blaster from the usb on the laptop, that's about as good as I can get without the valve amp. No change.

The creative is an external box with low level outputs. Much better than the headphone output.

ZENER

Have you tried just plugging one channel from the SB into the LFE input on the Sub ? In whatever program you're using to play the music use the graphic EQ to cut all frequencies above 200 Hz and see how that sounds.

It is possible that the room is colouring the sound from the Sub but I'm not so sure you'd get such a dramatic effect as you describe, unless the floor was made from cardboard !

How does your setup differ to the original listening setup ? Different Amp - Source - connections etc - was there carpet on the floor ? Maybe try a mat under the sub to try damping any effect the floor might have.

Ken

No eq all set to flat.

I didn't try one channel.

No change in the setup or room.

Same amp in me mothers. No carpet in either house in the sitting room.

My house is 2 story the mothers is a bungalow.

ZENER

Hard to advise further without hearing the setup but everything else being the same then the only change is the location from what you describe. Do any of the floors in your house have solid concrete rather than floorboards ?

Ken

Both houses have wooden floor over concrete.