hey guys/gals, my tempest has a adire dt300 amp on it and the box is about 65L sealed and has polyfill in it. The box is solid as a rock with plenty of bracing but when my sub hits with only a moderate amount of power to it the sub sounds like it is bottoming out. I can hear the sub make almost a low tone "pop" sound that happens every time there is a decent amount of excursion. Anyone know what is going on hear and how i can get rid of the problem?
clipper10,
I`m not sure at all if I correctly understand what You mean with "bottoming out".
But anyway here what I think:
Your box might have a leakage problem. Try (carefully) pushing the cone inside the box manually. When You release the cone it should go back in the center position quite quick. If the cone is "sneaking" back then Your box enclosure is leaking air.
Sorry in advance if I missunderstood something.
I`m not sure at all if I correctly understand what You mean with "bottoming out".
But anyway here what I think:
Your box might have a leakage problem. Try (carefully) pushing the cone inside the box manually. When You release the cone it should go back in the center position quite quick. If the cone is "sneaking" back then Your box enclosure is leaking air.
Sorry in advance if I missunderstood something.
if you find there are no air leaks and that you havent overpower
it. it could be the spider or the aluminum voice coil. if you over drive a speaker that coil slams the back of the magenet and dents it. wich in turn makes it rub.
that is if its not the sub box.😉 or only half fried do to that party you had last nite.
get the spider replaced with a stiffer one:scratch
it. it could be the spider or the aluminum voice coil. if you over drive a speaker that coil slams the back of the magenet and dents it. wich in turn makes it rub.
that is if its not the sub box.😉 or only half fried do to that party you had last nite.
get the spider replaced with a stiffer one:scratch
You might have some nasty subsonics going on, try adding a high order high pass filter at about 15Hz, and see if that helps.
well i pushed the sub in and it comes right back to position. I highly doubt that the box is leaking air. The cuts are all straight and i used liquid nails to hold and to seal the box. I am thinking there is something wrong with the spider. I think that this might be what is going on:
I think my spider is having a rough time. Now i just have to get a new one which i don't know how to do so i will probally end up with a new sub. My sub had no probs for a long time, almost 2 months, then this just started happening.
thanks for the help...
Maybe Adire will warrenty it for you. I think they do that. I always wanted a Tempest or Shiva but I don't think they have a distributor in Canada.
Pete
Pete
cocolino has got it backwards. If your cone returns quickly there are major leaks.
Tell us of your crossover. Active or passive?
Do you have a scope, oscillator?
The problem could be somewhere else besides the woofer/enclosure.
Tell us of your crossover. Active or passive?
Do you have a scope, oscillator?
The problem could be somewhere else besides the woofer/enclosure.
If it only were that easy !
If there's no leakage at all the cone returns quickly as well, simply due to the increased stiffness. If there is large leakage then the cone would also return quickly.
If there is some small leakage the cone will return slowly after being pushed in for long enough.
Just use your imagination.
Regards
Charles
I have simply not assumed that the leakage could be so big that the enclosure is virtually vented🙂
If you were using that 12" eminence sub that Madisound has on sale for 25 bucks a while ago I'd tell you that the problem is that your sub is a peice of crap with the worst excursion and worst tendancy to fly back and smack the backplate with almost no provocation.
BUT, since that is not the case, I will give you my opinion. I had the same problem recently making a powered sub for someone using the MCM rubber surround paper cone 12" sub ( a driver which I happen to think is a bang-for-the-buck champ, although it almost qualifies as a woofer and not a subwoofer on paper, it's performance always surprises me, especially in a car, and especially for 30 bucks) I had the same "bottoming out" sound coming out of it, but it wasn't a "smack", more of a "WHOMP", and after lots of messing around, I found that my SONY STRDA777ES had its LFE level at negative-something, and I had the sub amp gain way up. In other words, I wasn't giving the sub amp a strong enough signal to compensate for the amount of power that I was asking of it, and on long strokes it was running out of power before the sub had moved the distance required for deeper, louder notes.
Once I turned up my Low-frequency-effects channel on my receiver, the problem was solved.
I'll bet that's the problem.
BUT, since that is not the case, I will give you my opinion. I had the same problem recently making a powered sub for someone using the MCM rubber surround paper cone 12" sub ( a driver which I happen to think is a bang-for-the-buck champ, although it almost qualifies as a woofer and not a subwoofer on paper, it's performance always surprises me, especially in a car, and especially for 30 bucks) I had the same "bottoming out" sound coming out of it, but it wasn't a "smack", more of a "WHOMP", and after lots of messing around, I found that my SONY STRDA777ES had its LFE level at negative-something, and I had the sub amp gain way up. In other words, I wasn't giving the sub amp a strong enough signal to compensate for the amount of power that I was asking of it, and on long strokes it was running out of power before the sub had moved the distance required for deeper, louder notes.
Once I turned up my Low-frequency-effects channel on my receiver, the problem was solved.
I'll bet that's the problem.
If there is nothing that you can phyically see wrong with the woofer, I'd say Bill F. is on the right track. You may be getting some kind of sub-sonic signal or transient spike from the amp.
well i took my box out to the wood shop and decided the spray fiberglass around all the edges so that i know for sure that the box is sealed. Unfortunately, i can't really set the signal changes until i get the sub in the box. The signal might be the problem because i took the sub out and it seems to play fine when playing it in my car hooked up to a 400 amp(free-air), but i can't test it in my box yet. Once the box dries, i will try to get something to fix my signal problem. I think i can do it on my dt300, but the manual isn't to in depth so i will have to tinker a bit. I just hope that it isn't a sub problem. I know the box will be fine, the sub seems to be fine, so that leaves me with the signal.
...thanks for all the help....
...thanks for all the help.... It definitely sounds like it is an issue with the amp. Even in free air you should have trouble getting that driver to bottom out. In any box smaller than maybe 300L there will be some sorto of dampening, only reducing excursion. Basically when a driver like that is going to bottom out, you will watch it, and it will look like it is moving so incredibly far that you will be scared. When drivers move that far, even if they are supposed to, it makes me nervous. I have a sub that uses 12 inchers that go 9mm, and when they get up to about 5, it looks crazy.
Just thought i would let you guys know that it was an amp signal problem...It is weird because i put my 15 inch idq from my car in my home box and i had no problems. My tempest kept having problems. I read the amp manual and changed some things when i put the tempest in and all the sudden it worked and worked well. Now i am getting a lot of excursion with no bottoms falling out and weird banging noises.
Thanks you all and especially paulinator for the email pointing out what was wrong. 😉
That last post I did was meant to appear after one of the earlier posts in the thread, so it really seamed out of place.
I'm glad you got things working again. I feel lucky that I just went throught the same thing so we could get you through your's faster.
I'm glad you got things working again. I feel lucky that I just went throught the same thing so we could get you through your's faster.
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