Hi there,
I’m just testing out a design I’ve made.
Under a certain frequency a substantial chuffing noise is present, not unlike the port noise of a bass reflex sub.
Above this frequency it rapidly disappears.
I’m guessing this is just how a tapped horn behaves?
Thanks.
I’m just testing out a design I’ve made.
Under a certain frequency a substantial chuffing noise is present, not unlike the port noise of a bass reflex sub.
Above this frequency it rapidly disappears.
I’m guessing this is just how a tapped horn behaves?
Thanks.
No "chuffing noise" is usually present in TH designs. More likely to be an air leak around the driver or somewhere else in the cabinet.
Using a microphone through headphones to track down the leak can allow you to "listen in" to places you would not be able, or want to put your ears at the high SPL produced.
Using a microphone through headphones to track down the leak can allow you to "listen in" to places you would not be able, or want to put your ears at the high SPL produced.
Thank you.
Just after posting that I finally found the leak.
The mounting flange of the driver is a bit thin. I’ve found some neoprene sheet with which I’m going to make what I hope will be a better gasket.
Also there are a few splinters around the baffle/tap cut out. I’ll fill these with polyester filler.
thanks again
Peter
Just after posting that I finally found the leak.
The mounting flange of the driver is a bit thin. I’ve found some neoprene sheet with which I’m going to make what I hope will be a better gasket.
Also there are a few splinters around the baffle/tap cut out. I’ll fill these with polyester filler.
thanks again
Peter
I’ve now made the mating surface as flat and smooth as I can, and made a better gasket with some neoprene sheet and also washers for the machine screws I’m using.
There is still some air noise, but only below the driver’s Fs.
particularly around the rear of the driver. I think this must be to do with the communication between the two sides of the cone.
There is still some air noise, but only below the driver’s Fs.
particularly around the rear of the driver. I think this must be to do with the communication between the two sides of the cone.
Rear vents on woofers will make air noise at high excursions, some "wheeze" much more than others.
Designing for the required cooling air flow with minimum noise contribution usually has more production costs (smooth cast venturi shapes cost more than punched vent holes) though some cheaper brands have managed to copy what works best.
Designing for the required cooling air flow with minimum noise contribution usually has more production costs (smooth cast venturi shapes cost more than punched vent holes) though some cheaper brands have managed to copy what works best.
I tried blocking the rear vent- not much difference.
The noise appears to be coming from the suspension. It’s rubber and this is a very long Xmax woofer for its diameter. I think it’s just the way it is- the rolling motion of the rubber is just moving air.
I made very sure that there were no leaks around the joints when I constructed the cabinet.
Plus- I haven’t yet tried the sub with a mid/high speaker, so any air will gave been much more apparent so far.
thank you.