chevyin
1/2 ton status
Glad you are gettin her done, and are happy with the results. Ya, its amazing when you hear new sounds in songs that you've listened to for years, aint it. 
CK5
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Which amp/speaker setup? UPDATED...
- Thread starter 73k5blazer
- Start date
Z3PR
Banned
I love car audio. I'm a poor boy so I've built my system over a period of time. I'm not done yet, there will be upgrades, and upgrades. Over all, I'm pretty happy with the sound of it. I'm always happy too hear about others decovering what car audio can be all about.
So I was out fiddling again with it (well, just listening really I couldn't help myself), so I've never had a sub in a car before (I guess my GTO has one, but's it buried under the rear shelf infront of the gas tank and it's pretty small), how much are those things supposed to move. When I crank up the volume, it still sounds really good (I was very anal about vibrations, I insulated and padded everything screwed into that side panel so I wouldn't hear any that nasty mashing/buzzing/loosness you hear so often in alot of cars with haphazzardly installed subs), but that sub really moves alot. A good inch or more. I realize that's it's purpose, to move air, but how much is too much. It's rated 350w, in a free air mount (which mine is) 175, the amp is 500@2ohms, 250@4ohm, and I'm guessing 125@8ohms which is how I have it wired.
I'm probaby just being paranoid....
I'm probaby just being paranoid....
Z3PR
Banned
My 12" DVC Kicker L7 is rated at 750 watts RMS and I'm powering it with a MMATS D200hc 1200 watts RMS (MMATS under rates thier amps. This amp is closer to 1800 watts.) with the gain turned down.
chevyin
1/2 ton status
I did some research on Infinity's site trying to find cone excursion specs, but couldn't find them. With that being said, the cone moving an inch or so would give it an xmax of about 25mm. The average good quality subs today are in the 15-25mm range, so yes its quite possible your cone is moving that much.73k5blazer said:
How much is too much? Its too much when the voice coil starts slapping the motor's backplate, which will make a awful banging noise (not to mention flatten your VC). This would be the case on a "motor-limited" subwoofer. In "suspension-limited" subwoofer, the suspension itself will be the limiting factor in the max length of cone motion. This means the sub's suspension (cone surround, spiders, etc) will limit maximum cone motion before the voice coil starts slapping the motor's backplate. IN this case, the sub will simply become very distorted, rather than making the slapping noises of a motor limited sub. This happens because the suspension, when being driven past its operating range, will allow the cone's motion to become non-linear, thus distortion occurs. This can lead to suspension failure very quickly (torn spider, ripped surround, etc). Both architecture types are popular today. I do not know which yours is wqithout doing more research, but its probably motor limited.
The way to avoid 'bottoming out' your sub is to set everything up correctly to begin with. To understand why a speaker bottoms out, you need to understand the basic physics of how the enclosure size/type and power available affect your sub's cone movement. If you already understand this, forgive my redundancy here.
As you know, for a speaker to make sound, it must move air. The more air it moves, the more sound its capable of producing, and of lower frequency (speaking in very basic terms here, other factors affect this somewhat as well). Two basic things restrict cone motion, the speaker's own suspension, and the air cushion created by the enclosure itself, both of which are always trying to bring the cone back to its centered home position. The more power (watts) you apply to the speaker, the more force is exerted to move the cone against these forces and push it farther (obviously). Therefore, more wattage moves the cone further. So the first step towards avoiding bottoming out your speaker is by not overpowering it given the enclosure it resides in, we've already discussed how running a speaker infinite baffle (or sometimes called free-air) drops its rated power handling... this is why. The second way to avoid bottoming out your speaker is by placing it in the proper sized enclosure (again, enclosure size/type and power handling go hand in hand). If the enclosure is too big given the power coming to the speaker, the air cushion created by the enclosure offers too little resistance, and the speaker's cone will be pushed beyonds its limits. So, placing a speaker within the proper sized enclosure and remaining within its proper power handling window should keep your cone's motion safely within its limits. But remember, improper gain settings can allow more power to a speaker than the amplifier should be pushing, so setting your amplifier gains properly also affects this situation (on the pwer side).Hope that explains it, sorry for the long post, I get carried away sometimes. Basically, just do a critical listening session while being conscious of a banging sound (motor bottoming out) or audible distortion (suspension allowing non-linear cone motion). If neither of these occur, your sub should be just fine.
Hey, thanks alot again. In playing with it some more and watching and listening, I think it's fine. I said an inch, but it's hard to really estimate how much. I couldn't hear any slapping or odd noises coming from it. Just crystal clear sound.
I'm sure most of the time, I doubt I'd have it that loud anyway. It was really cranked.
I'm sure most of the time, I doubt I'd have it that loud anyway. It was really cranked.
chevyin
1/2 ton status
73k5blazer said:
