Brand new subs nearly no bass?

[Denven 0]

So i recived my Fi BTL n2 12"s which are 2x2 dvc and wired them like this:

Voice coils in series and woofers in parallel should give 2 ohm final load (reads 1.3ohm on DMM). My RF 2500bdcp amp does 3500w at 2 ohms @ 14.4v (not sure if i shall belive the birthsheet)

The woofers are mounted in a temp ported box till next week when i build my enclousure which will be 4.5cu after displacment and tuned at 33hz.

As it is now it dosnt give out much bass at all, don't know if they are out of phase or that they are brand new and stiff as hell or it just might be the box.

My voltage is steady even at full volume before clipping. (14.7v) i've scoped everything to make sure nothing clips.

woofers dosnt get hot they are ice cold , but the heatsink around the RF amp get really hot but on top of the amp its just warm.

My brother got two kicker cvx 12" running at 1800w 1 ohm and they pound. and i did the wiring :S so something must be wrong...

Power and ground is 0ga, speaker wire is nice and thick, XSpower d3400 up front and 270a dc power alt.

Hope someone can find the problem, there must be something wrong :s

[///M5 2,833]

don't know if they are out of phase

Then check, that is Step 1.

[Denven 0]

Aye, will do when i get my car back.. Going to reverse the wires at the amp and see if i get more output. Or try that 9v battery trick i've been reading about if its recommended?

[///M5 2,833]

Battery will tell you more since if out of phase they will move opposite directions.

[jonbearsmt 919]

9 times out of 10 the symptoms lead to being out of phase

[NDMstang65 403]

Or your crossover is turned all the way down and your subsonic filter is on..

[brian p 1]

check phase

[Denven 0]

Tried that 9v battery tick, subs didnt move at all. Changed the wiring at the amp and felt little increase in output. Getting late so can't do nothing atm.

Funny thing is, i thought i knew "everything" but now is the first time i heard of "out of phase" after a few google searches

[Godsmack 360]

The day you know everything is the day you should die. NEVER stop learning, searching for knowledge or listening.

J

[Hzd Skizzy 27]

try what nick said maybe? check your ssf and lpf on your amp.

[Denven 0]

the ssf switch on rf mono amps is at 28hz when its on, i turned it off for now, lpf not sure where its set, kinda hard to tell where its set, i usally just set it low and turn it up while listening to a bass heavy song and stop where i feel its good. Will take the subs out tomorrow and tripple check the wiring again, and perhaps take a pic at the same time to show how its wired

[trevorb9 2]

the ssf switch on rf mono amps is at 28hz when its on, i turned it off for now, lpf not sure where its set, kinda hard to tell where its set, i usally just set it low and turn it up while listening to a bass heavy song and stop where i feel its good. Will take the subs out tomorrow and tripple check the wiring again, and perhaps take a pic at the same time to show how its wired

Your crossover should be set at about 80hz, If it is turned all the way down you wont get much output.

[Denven 0]

sub1

sub2

hope you guys understand the pics, this is how its wired. VC in series and woofers in parallel. Is it out of phase ? this problem is new to me and is confusing -.- wiried the subs as the diagram at the12volt.com showed..

I did wire my brothers subs and they pound at 1800w rms 1 ohm, and they are kicker cvx's -.- they hit way harder that what i have and he got voltage issues.. so something must be wrong. perhaps it may be the mosfet in the amp that is bruned or something..

[Denven 0]

Sorry for dubble posting, couldt find the edit button ? -.-

Anyways the 9v battery trick now finally worked, and they were moving inwards. so i've changed the wiring and now it looks like every thing is wired in series but they are moving outwards which i suppose it means they are in phase. still reads 1.3 ohm though. so i guess the problem is solved. Havent tested it yet.

[///M5 2,833]

If they are in phase, your amp settings are okay, then it is time to measure input voltage to the amp and output voltage from it with a test tone that is in the range of where you will play your bass. Nominally a 40Hz tone should work.

[Denven 0]

Will do that =) going to connect everything back in tomorrow.

Disconnected all the wires and did the "pop test" again with a 9v battery. When i connected the + from speaker to + on battery and - from speaker to - on battery the cone moved inwards, when i reversed the connections it moved outwards and when it move outwards means that the polarity is correct? and inwards is out of phase?

Might be that the terminals on the subs are marked wrong or i'm just missing something heh.

Just want to make sure thats all :>

[Angelboy863 21]

Sorry for asking on ur thread but whats the recommended ssf and lpf on a 400 watt mono amp at 2 ohms to a 4 ohm dvc 400 watt sub? Oh and the box is ported tuned around 30-32hz

Edited September 11, 2011 by Angelboy863

[shizzzon 461]

i dont use rule of thumb so the proper way would be to measure and test the crossover points yourself as that will answer your question.

[Angelboy863 21]

i dont use rule of thumb so the proper way would be to measure and test the crossover points yourself as that will answer your question.

Soo.. Just play with it? I don't have any equipment but I keep telling myself to get some.

[shizzzon 461]

all u need is a dmm, some test tones and your eyeballs

[Angelboy863 21]

I see, thanks. Don't forget ears lol

[jonbearsmt 919]

pic looks good on the subs. but i have seen people switch it up once they get to the amp. insure that they are going into the correct spots...

a simple way to rule out phase IMO is to remove 1 speaker wire while its playing. if your output mega changes then you have a phase issue.