I made a new home for my baby b12 (2.25cu@23hz), and it dosent seem to like it! I made sure to seal the box very well. Im running a JBL 1200.1, and whenever I play roughly 80%, my sub sounds like it hits something, and then the music stops for a sec, and I turn it down really quick. I thought that lower tuned enclosures were supposed to be more safe? Ah, this is driving me insane. I know seth built a 2.0@24hz, and he put 1700 to it (unless I'm remembering wrong?). Anyways, help a brotha out! Thanks.
There are a few things that it could be, and bottoming it out isn't one of them. First, bottoming out quite often sounds the same as clipping your amp. Might want to check your gains or chill on the volume knob. You shouldn't need to clip that amp with that kind of power...1200-1400 wrms is plenty. Clipping just isn't worth it in this case. I don't know what kind of music you're playing, but the JBL doesn't have a ssf, so if it drops too low, it might begin to unload (uh oh!). Don't want that either. I would either buy a ext. xover with a ssf, or buy an fmod, and recheck my gains.
so bottoming out wont make a loud profound sound? hmmm, that sound that comes from that speaker is scary! Im just scared that i might fuck it up. Im going to go reset my gains and see if that helps. thanks for the help BTW, i meant 45/50 while 50 being maxed out gains, not maxed out headunit (goes up to 66)
A sub bottoming out won't cause it to stop playing, it'll only make a popping type of sound. If you're gains are nearly maxed out...turn them down promptly. There's almost no reason to have your gains that high unless your HU has very very weak preouts. That could cause your amp to go into protection momentarily.
Sure it will. But it is physically impossible to bottom out the Brahma. Even if you cut the surround and spider, the voice coil would still never hit the bottom. The dust cap would hit the pole piece first. Unless you set your gains with an O-scope, then that is probably too high. My guess is what you are hearing is clipping, as someone else said, and it is letting you know that the gains are too high.
probably has something to do with when i changed from 4ohm to 1ohm. i didnt change the gain because i remembered hearing from totoro that the gain would be in roughly the same spot? When i get my gain setting cd back from my friend, ill besure to reset them. I didnt know that clipping made a popping noise tho. Learn something new everyday i guess
totoro was right. the gain setting should not change... it has nothing to do with the output impedance, only the imput voltage from the HU. If your gain is that high, you must have one shitty HU(like stock) to have that low of output voltage. RARELY do I see a need to have the gains above 3/4 and on most amps about 1/2-3/4 is usually maximum you should have it at.
Sorry for the confusion. what i meant to say was that i SET my gains when the volume was at 50/66. Also, I put my old box in there (1.5@28hz), and it works fine now. I guess ill just use this one for awhile.
May be the hungry beast is taxing your electrical system... does it sound like a shut off or turn on bang? Like a pop, but a lower frequency? If so, that 1200 is taxing your system and shutting down. I have found that the 1200 is VERY power hungry for a class D... My Z7000 (class AB) putting out ~300 more watts (the 1200 is actually capable of about 1400 watts) and draws less current!!! That is an unmentioned possibility, but I am feeling the others when they said clipping... Sounds like you are clipping to me. The shutdown is likely thermal and due to the clipping. By running the smaller enclosure and higher tune, you are shifting the impedance of the woofer, as it does change in dynamic operation. When the dynamic impedance is raised, the power becomes less (remember, the lower the impedance the higher the output of the amp, and vice versa ). When the dynamic impedance is lowered the output of the amp is increased, and more suseptable to clipping. what HU? The sub out is zero, I know... and the BP1200.1 is at 50%? The 1200 has a rated input of 5 volts to .250 Volts I believe... someone correct me if I am wrong. Let's see if you are clipping that amp. :detective:
Yup, clipping alright! It never occured to me that when changing boxes, you change the gain. BTW, I do like the new box better because it just seems more accurate and less peaky(which is why i made it). The low end is also VERY nice.
