ncc74656

i dont know what to divide by as it changes every frequency

i measured with a volt meeter on VAC and divided by 2ohm as thats what the sub is rated at.

ok. RCA's have 0.7V AC kicker amp sits at 1.1v at rest with gains/bass boost down. turning up gains will move this to 1.6 and bass boost will bring it to 2.7V while playing the amp peaks at 51V ac at 33.4hz my eclipse amp shows 13.3V on one channel and 11.1V on the other at max volume max voltage drop at amps with engine off is .8V and nominal is .34V subs best volume by ear is with gains 3/4 up and bass boost 3/8th up by my math the most this amp puts out is 1300W in its current setup.

i just downloaded an android app to play some tones. im goin out now to play aorund with things.

yes it was bloody loud and set of car alarms. not long after that it was shooting fire into my cab. also durring this loud phase it was also not good at producing high frequencies, it was to powerfull at lows and not enough at highs. i just reconed it yesterday and just installed it today. with gains down and bass boost off it has no power. but turning these up set it on fire the last time... so how do i get power with out using gains and bass boost

part of my "information" is the white powder from the fire extinguisher that's still stuck in my upholstery of the truck cab... let me run through this here and see what you guys think, a local car audio shop wants to hire me to do installs so if/when that happens i will have access to more equipment to play with. now let me start by saying that this sub got bloody loud, when i went to the audio shop to show it off there were customers there who had there SUV's full of subs 3 or 4 12's and when i turned mine up they walked over to see what in the fuck was setting off alarms down the block. now lets go to what my actual goals are - this is where things get complex. i prefer bass in the higher frequencies (45-80hz) but i dont want to be missing the 30-44hz range so i want these to be more balanced. even at max volume the SP4 was not loud enough for me. now it should be said that installers at the audio shop did not want to stand near the truck for to long as it was "to loud for them". I am looking for bass that is clear and musical while at high volume can shatter my windshield and provide enough air to eject things from the truck cab. the first box i had for this was to small cubic and to high a tuning. had great high bass but zero low end as the sub was unloading at around 39hz. second box had a messed up port that caused muddy bass. this box is fixed and is tuned to 32hz at 7.2cubic. I have mechman 280amp alt, knu conceptz 0ga and OFC for long runs. 4 group 31 liquid batteries, all cables bolted directly to the battery studs with brass washers and bolts, all wires soldered with electrical solder and copper ends. amp grounds to the frame and frame has been ground down to metal for good contact. wires going into amps have shielding cut back and the strands pushed in and the set screws cranked down. longest wire run is about 12ft. head unit is pioneer with shielded RCA's going to a KX3 and then out to there respective amps. the ZX2500.1 does not go through the xover as i think its got the same xover built into it, no? the alt has 0ga ground and power going directly to the battery. the amps all connect to a 3/8" plate of copper that is a common link between all the batteries and this has sets of ANL fuses coming off it. the box is 1.5" mdf build with 45 corners, a rounded port opening, glue and screws. 8ga wire from amp to sub. now i noticed today that when i turn my decks EQ up on the 100hz range that my tweeters distort. why is this? they are xovered at 4.5KH on a very expensive xover. i should be able to push the 100hz up to 50 and still not get any bass to the tweets.

i dont want to use bass boost. the whole idea of bass boost seems stupid to me now that i have looked into it more. boosting db at 40hz and no other frequency? with bass boost off i dont get volume. it sounds like my 15" vidsonix and at most im using 5-10% of xmax on the sub. when bass boost is turned up the volume kicks in and i get much more movement out of hte sub but the cone gets FU**ING hot. im going to install an amp meter into the power line of hte amp to see what its pulling in real time. ill go to my local audio shop and get the amp bench tested monday i want to monitor the sine wave coming out of the amp and record it on a computer. how would i go about doing this? im sick and tired of being in the dark, i want to stop "using common sense and going by ear" and i want to get some hard, raw data on this so i can dial this in mathematically and if/when something blows up i will have data to tell me what it was doing at that moment. i do not feel that this amp/sub setup is doing what it was built for and i do not feel that this amp is putting out any power with bass boost and gains down. should an amp not be able to put out rated power with out its gains up? if gains kill subs why would i want to turn them up at all?

how? i dont understand this. the amp is a 2500W, 2800-2900 at 13.3. the sub is 3KW and ive added the cooling so 3200-3500W should be no issue for this sub. in either case with out bass boost the sub has no kick to it at all so idk... i feel like im not understanding any of this. there is no conceivable way that this amp can provide enough power to over load this sub on a non clipped signal. so i dont understand what you are saying? do i need to buy a 5KW amp so i can provide proper power to this sub with out bass boost? i can do that, ill go out and buy a BC5000.1 tomorrow if that will allow me to use this sub to its full potential.

the sub is installed, took nearly an hour to get the damn thing mounted in the box. doing a virtical mount in theback seat is hard. bass boost 0, gains 0% (dial on amp), all deck settings at 0 or off. max volume on deck provided next to zero bass, so little excursion that you really couldnt see the cone moving. deck at +4 to sub, amp gain at 50% (dial on amp); at max deck volume it sounded about the same as my 15" 350W sub i had in there to get by with. max volume on deck, 50% amp gain, +4 head unit, 1/3 bass boost; gave decent bass but still not as loud as i want. so here is my question. how high of a gain should i do on this thing? i feel that i need to MAX the gain to get any power into the sub. How can i tell in real time if the signal is clipping? I modded the box and added a second layer of wood on the inside of the drop down port thus correcting my error when building the box originally. this brings the box to a 32hz tune @ 7.27 cubic. the bass response sounds much better with this change, its able to more accurately reproduce differences in bass frequencies where as the previous build was kind of muddy through out certain frequencies. with no bass boost the dust cap is getting warm, im not sure what to do about this? how hot is to hot? i would like to know a temperature that is to hot so i can monitor it to be sure it does not catch fire again. my voltage is holding steady at 13.5V which it did not do before, im sure the bass boost was causing the amp to try and pull way to much power and that is why my alt could not keep up.

i just got everything hooked back up and the cap is still getting warm. its not burning hot like it was before but it is warm. is there a certain temp i can set as a threshold? i can use a ir thermometer on the cone as the sub is running to monitor its temps.

how is my electrical not up to par?

ive got a 32 channel EQ now so im about to go outside and do this. ill post up on here what results i get with various boxes.

i love how this question of "my cone is getting hot" ended in the sub setting fire to my truck...

it cought fire, set fire to my box and truck cab. It is assume it was being clipped by bass boost.

lets start with my childish goals first. I would like to have a system that moves enough air to do hair tricks, can shake everything, and bassicly beat out the guy next door. my real goals are to have a system that can play MUSIC at very loud volumes and retain its clarity. in previous posts i learned that my prefered bass range is in the 40-70hz range. I do not want to sacrafice the low end volume to obtain the high end and i want to have less peaks than my present sub. some peaks are going to happen and i understand that but i do not want to have 50db@33hz and 8db at 50hz. i have a ZX2500.1 so that is why i was thinking of going 2 Q's to obtain a wider and flatter response in sealed and more cone area to retain volume. as for the volume i am looking for... i have 2 sets of alpine tweets right now and at max power they are not quite loud enough for what i am looking for. so i want this sub setup to be very loud. edit: i will be putting my SP4 into a sealed box today, testing it in a new lower tuned box today, and testing it in a variety of higher tuned boxes. i may end up keeping it if i get what im looking for but if i dont i THINK the Q is my next step.

11 cubic for 2 Q 18's. i want to retain the 33hz volume as much as possible but i absolutely want to reach 75hz at a very good volume out of these. my idea was to go 11 cubic and put a bit of poly fill inside. it is not for certain that i will buy 2 Q's, i will know after i test my rebuild SP4 to see if i can get the volume i want out of it at the frequencies i want. im expecting i wont be able to. this would be the box design:

if it is bad ill just sell it, im not sure i want to keep it anyway. there is nothing down in the gap

how much power could one safely put into a fully loaded Fi q 18? i got my sp4 fixed and will be testing some boxes but if i dont get the sounds i want i am going to sell it and buy another sub. the Q seems a logical choice as i want more frequencies but also want to keep the volume. i am undecided on single or dual or sealed vs ported. my thought was that if i replace the SP4 i would get 2 q's and thus have greater cone area with more control and higher bass frequency range. in my mind that would mean i could get more volume out of them than the sp4. the power handling would be close to the same

the videos I watched said to shim and glue the spider while pressing the surround into its track. wait 15 min or so and glue the surround one bolt hole at a time. then put on the dust cap after removing the shimms. the noise makes me think the coil is slightly sideways. I think in the 40 seconds it took me to get the spider clamped the glue might have hardened in a lump on one side.

I did the surround one bolt hole at a time. yes I just put the dust cap on.

2 hours

I glued the cone in, there is a slight scraping noise when I press it down. I think the clamps pushed the spider over when I glued it. think it will be an issue? I used 8 slits of manilla envelope to shimm it. doubled up on 4 points.

i feel i need to post this if for nothing else to clarify for others who read these posts. yesterday i noticed my new speaker started to rattle and would stop moving from time to time but not at rest, it would remain sucked in or poped out. same thing the last speaker did but my driver side speaker has not blown yet. i noticed that the power going to my driver side speaker would greatly increase when the passenger side would stop moving. today i tested my old PWX 10 on my home amp and it is not blown, no way no how. so my amps right channel is whats screwing up. for some reason it stopped messing up after i replaced the speaker?

getting my recone today . ive watched many videos on the process. it seems i use cardboard to shimm, using 4 peices placed around the coil or doubling up on them if needed. glue the spider down and clamp it. after 15 min or so i glue down the surround in 5" segments until i make it all the way around. center the dust cap and glue that down, screw the leads back on and then wait 12 hours before i test it and 24 hours untill i play it? is there anything else i need to know?

i was going to take the large box and slowly cut .5 cubic out of it at a time and test its response. i wanted to see inside my truck how the acoustics worked progressively. however my sub caught fire, set fire to my box, and set fire to the roof of my truck cab before i was able to finish this. my recone arrives tomorrow so ill be starting up again then.