snap sound from sub
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They do hard bottom.
My second 15" AA blew because I had a Lanzar Opti2000D that advertised a "soft turn on/off" which muted the amp 7 seconds when turned on and 7 seconds before it would shut off. I was testing a 4th order bandpass box, I hadn't sealed the sub in there permenantly yet, and when it passed I set the side panel against the wall then disconnected the remote wire. WHACK! The sub was next to free air with the side panel off, and the amp did a massive turn off pop common to some car audio amps. The coil was smashed and unwound.
My 1st 15" Ava I ran in a 4.5 cubic foot sealed box in-car, and it kissed the top plate a few times on some low tunes. Neither driver had any damage to the tinsel leads from over excursion, the spider and surround allowed one to push the cone in by hand until the coil was on the top plate.
Tinsel slap was an issue a few times with other people, so I heard, despite the slap pads. This could be his issue.
Here is how it was when the amp did a "shut off pop"
this is what it looked like after
After I was done playing with 4.5 cubes, I cut the box in 1/2 for two 2.0cf sealed boxes. Both of them are dead in this pic
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it was sealed! Music. But yeah, I got ya anyway, over excursion is over excursion, if it's not bottoming out, either he's torn a tinsel lead thats floppin around, it's normal tinsel slap, (not likely, shouldn't be that loud with slap pads) clipping, or some other culprit...
I've never physically heard tinsel slap before, so i woudlnt know what it sounds like. The subs I have dont have that problem. I thought it was more along the lines of the FI and RE subs, the xxx in particular. But I received my b-1 today and im going to give it a shot.
My problem is solved! I can actually turn it up to decent levels with my ssf in. Thanks everyone! Now my next question is would running this in bridged mode fry the coils? I know they were rated at around 800 roughly, and i know they can take a bit more. There are some people running 1k daily music systems in their car. Going by whats been measured it seems the ep2500 makes around 650-700 in stereo mode with a 4ohm load, and in bridged mode it makes a measured 1600 before the breaker gives out.
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The xxx and Fi subs should have very similar excursion and tinsel leads. They have slap pads as well. The ava's can slap, but it shouldn't be loud, not like what you seem to be hearing.
I don't see any reason not to maximise an amp's output and turn the gain down. If you only need 1000 watts and your amp does 1000 X 2 or 2000 x 1, hook at X1 and keep the gain down so it is 1000x1 bridged. I'm not sure, but I believe it doing 1000 x 1 bridged is easier on it than working hard to do 1000 on 1/2 the amp, 1 channel. You can always lower the gain but wire it up to optimise the amp.
Keep in mind if you do give it more power though, it will bring your excursion back up, so at those frequencies with as much power as it had before the filter, the issue will return. IMHO I think you need to find out what is happening. Are you simply reaching the driver's limits? If so, keep the power down. Is something loose or broken? A speaker wire slapping the inside of the box? Fix the problem, don't just filter power in that region and ignore the problem.
I don't see any reason not to maximise an amp's output and turn the gain down. If you only need 1000 watts and your amp does 1000 X 2 or 2000 x 1, hook at X1 and keep the gain down so it is 1000x1 bridged. I'm not sure, but I believe it doing 1000 x 1 bridged is easier on it than working hard to do 1000 on 1/2 the amp, 1 channel. You can always lower the gain but wire it up to optimise the amp.
Keep in mind if you do give it more power though, it will bring your excursion back up, so at those frequencies with as much power as it had before the filter, the issue will return. IMHO I think you need to find out what is happening. Are you simply reaching the driver's limits? If so, keep the power down. Is something loose or broken? A speaker wire slapping the inside of the box? Fix the problem, don't just filter power in that region and ignore the problem.
You come from the 12v world so you might know what im talking about. My car system consists of a single 15 RLP. I measured at around 142db at the dash. Now the tune on that is about 28hz. My reasoning is that my ear isnt used to such low tunes. Im used to more musical subs that have a larger range than these dedicated HT subs have. So I might be having higher expectations from the sub in the HT application. I have a a2-300 that knocks on music, but for real HT duty, it bottoms out too quickly.
I doubt its tinsel lead slap. Im not sure why its bottoming out, other than a poorly designed box. I spoke with i think Nick the owner of AA and he was recommending that I did not go with a PVC pipe. For some reason he did not like to use them in his installs and prefrered the traditional L port. The speaker wire would be non issue and even if it was, it wouldn't sound like what was happening before.
I doubt its tinsel lead slap. Im not sure why its bottoming out, other than a poorly designed box. I spoke with i think Nick the owner of AA and he was recommending that I did not go with a PVC pipe. For some reason he did not like to use them in his installs and prefrered the traditional L port. The speaker wire would be non issue and even if it was, it wouldn't sound like what was happening before.
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142 with a 28Hz tune? That's sweet! Was that on the TL?
HT subs are more musical and have a larger range! NOT BTLs and other heavy motored drivers with low Vas, low Xmax, high BL, high inductance.
If you tuned a Maelstrom high in a small enclosure, it would knock too... maybe not as hard though.
Nick is an employee, Scott is the owner Nothing wrong with PVC other than possible resonance...Sonotube may be better... but round is better than slot, if not equal to.
HT subs are more musical and have a larger range! NOT BTLs and other heavy motored drivers with low Vas, low Xmax, high BL, high inductance.
If you tuned a Maelstrom high in a small enclosure, it would knock too... maybe not as hard though.
Nick is an employee, Scott is the owner
Nothing wrong with PVC other than possible resonance...Sonotube may be better... but round is better than slot, if not equal to.it was one of them, i always get them two confused. Well then do you have any idea what the problem is? I think the upper frequency's are completely lacking. but the lower ones are amazing, shakes the whole room. I do have a bfd and I have yet to do measurements. Also do you know how with car audio we tune with scopes to get the maximum out, is that possible with a HT sub? Say I leave it in stereo, and I want the full 700 safe watts. Could i just run a test tone at say 30 hz, and ramp up the amp to max?
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you can use a scope to check for clipping, but thats just my point... if you only need 1000 watts from a 2000 watt amplifier (I am just using these as easy numbers, I have no idea what you have available or what your requirements are) but your only running 1 channel thus forcing the amp to work hard, if you bridge it, you don't have to check a thing... you've got double what you need, headroom, and you just back the gain down. Why run a multi channel amp only using a single channel for a single sub. Bridge it.
I completely understand. I had it set on bridged before, and the members recommended I set it to stereo just to check the bottoming out issue. I havent set it back yet just because I know for a fact that 700 watts wont kill the sub. Setting it to bridged mode opens up 1600+. I just dont want to fry the coils on that much power. Now I know limited time periods with that much power wont hurt the sub one bit. But still I dont know how much to set it at. In a car I only have one point to match the gain....between the headunit and the amp. With this setup, I have the recv to the reckhorn to the ep2500. That introduces another point to voltage match. I hate not being able to set this stuff definitively.
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I personally believe less clipped power can cause more damage than more clean power
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