Down-firing “front” ported subwoofer

[Yorkshire Mouth]

If you have a down-firing sub, and it’s front-ported, obviously you don’t want that port up against a wall.

But automatically, I’d think of the ported side as the ‘front’ - almost always the controls and inputs are on the opposite side - the ‘back’.

Does it matter if you have one of the ‘sides’ against the wall, so the port is firing sideways, and the controls are on the other side (and more accessible)?

Cheers.

 

[sarumbear]

If you have a down-firing sub, and it’s front-ported, obviously you don’t want that port up against a wall.

But automatically, I’d think of the ported side as the ‘front’ - almost always the controls and inputs are on the opposite side - the ‘back’.

Does it matter if you have one of the ‘sides’ against the wall, so the port is firing sideways, and the controls are on the other side (and more accessible)?

Cheers.

such a strange design…what make/model is that?

 

[moonlight rainbow dream]

The orientation matters very little, as long as you are not interfering with the operation of the port. I think the rule of thumb is to give at least 1x port diameter of spacing. We do know however that changing the position of the bass source even by just some inches can alter the modal interaction with the room, changing the perceived bass quality by a lot. This is probably what people who claim a big difference when they turn their subs to face in different directions are experiencing.

 

[Yorkshire Mouth]

such a strange design…what make/model is that?

JBL Professional LSR310S

10" Powered Studio Subwoofer With XLF Extend your system LF all the way down! The LSR310S subwoo...

jblpro.com

 

[test1223]

At the bass reflex port a high amount of airflow at a small diameter occurs so you have to be aware that you can excite all objects which are close to it. That can cause sever distortion.
Also the listener can be effected by a higher air flow. There is no dispute that you can feel the difference in bass tactile perception at small distances. If the distance increases the effect should decrease significantly.

 

[Yorkshire Mouth]

At the bass reflex port a high amount of airflow at a small diameter occurs so you have to be aware that you can excite all objects which are close to it. That can cause sever distortion.
Also the listener can be effected by a higher air flow. There is no dispute that you can feel the difference in bass tactile perception at small distances. If the distance increases the effect should decrease significantly.

Okay, so taking that into my real-world usage.

The sub will be under a desk, with me sat at it. It will be to my right. To the right of the desk there’s nothing until the wall. So, better placed with the port facing to the right, so nothing is in the way, and (conveniently) with the controls on the back facing me.

 

[fineMen]

Okay, so taking that into my real-world usage.

The sub will be under a desk, with me sat at it. It will be to my right. To the right of the desk there’s nothing until the wall. So, better placed with the port facing to the right, so nothing is in the way, and (conveniently) with the controls on the back facing me.

Do you have it already? I wonder why this "downfire" thing is still around. Speaker cones tend to sag. That happend to ruin a few dozens of 'new old stock' drivers I once purchased. You may want to avoid such designs, or in case chose an orientation that keeps the driver's cone surface in line with gravitation--the standard orientation I mean.

 

[Yorkshire Mouth]

Do you have it already? I wonder why this "downfire" thing is still around. Speaker cones tend to sag. That happend to ruin a few dozens of 'new old stock' drivers I once purchased. You may want to avoid such designs, or in case chose an orientation that keeps the driver's cone surface in line with gravitation--the standard orientation I mean.

Not yet, but I’m looking at a pair of JBL 308Ps, and this is designed to go with them, to the point where balanced outs from source go into the sub, through the crossover, and out from the sun to the monitors.

 

[fineMen]

Not yet, but I’m looking at a pair of JBL 308Ps, and this is designed to go with them, to the point where balanced outs from source go into the sub, through the crossover, and out from the sun to the monitors.

I tend to say that JBL knows what they do. Regarding my misshap, it was like 15 years back, and the drivers were sitting on the shelf for maybe 10 years? They developed a sag of about 1..2mm that couldn't be corrected. So, if you don't plan for a once in a lifetime purchase, you may also ignore my caveat emptor ...

 

[Yorkshire Mouth]

I tend to say that JBL knows what they do. Regarding my misshap, it was like 15 years back, and the drivers were sitting on the shelf for maybe 10 years? They developed a sag of about 1..2mm that couldn't be corrected. So, if you don't plan for a once in a lifetime purchase, you may also ignore my caveat emptor ...

Me too - if JBL are good with it, it'll do me, for now at least? I've also had maybe 6 subs in my time, only one of which wasn't downfiring. So far, so good.

Lifetime? It'd be nice to say "I'm buying this, I'll never have to buy ever again", but experience teaches me otherwise.

Thanks for the tip, though. All welcome.

 

[ryanosaur]

In terms of near field listening, I don’t think you have anything to worry about. I have two different “desk” subs that have unique driver and port placements and haven’t noticed any output issues. Same is true with my experience with down firing designs.
More than anything it’s your usage and listening expectations that will matter most. Is this in a shared office space? Home office? Is your listening just for personal enjoyment or are you mixing or creating content?
My situation is home office and my main rig is in the room with me, so the weird subs are really just their for giving more full range playback from the computer and anything more serious is done on the real audio system.

Short version… you’ll be fine as long as the Sub works for your needs.

 

[Laserjock]

I tend to say that JBL knows what they do. Regarding my misshap, it was like 15 years back, and the drivers were sitting on the shelf for maybe 10 years? They developed a sag of about 1..2mm that couldn't be corrected. So, if you don't plan for a once in a lifetime purchase, you may also ignore my caveat emptor ...

Just store them flip them over the opposite direction for ten more years.