Help with mt

[2loud4u 10+ year member]

Ok here is the story on it.

12" Mt 3 cubes @ 35hz 50 square inches of port area

Dual 1.4 ohms coils

Wired to the amp it reads 0.6 ohms.

2500D @ 0.6 Ohms

Voltage at speaker outs 50v

0db 50hz test tone

head unit turned up 3/4 of the way

Sub controll all the way up.

Voltage is a Steady 14.2v car on.

Just not getting loud at all.

50 hz test tone sounds some what loud but no wheres close to what it should be doin.

During songs the voltage at the speaker terminals is 20.2v max

Setting on 2500d

Gain set with 0db test tone

Intelli q set to 0

Hpf set to 30hz

low pass set to around 80hz

phase set to 0

12db slope

I am alittle upset I thought this thing would get loud but not even close.

even with the trunk open and play throw it up ect... the sub hardly moves and also very little air comes out the port.

Click to read more...

 

[2loud4u 10+ year member]

No one can help me out?

I just went out and played little jhon throw it up and voltage at the speaker teminals did not go past 21v.

Maby I need to use a -3db test tone.

But I dont know.

Any suggestions are more then welcome

 

[2loud4u 10+ year member]

I am so pissed all this work and did not pay off.

 

[mazdakid 5,000+ posts]

take a pic of the side of your amp the settings are set at right now

 

[SAG3 5,000+ posts]

pound the gain

 

[coolahan 10+ year member]

pound the gain

hahahha i was gonna say it but u beat me to it

also turn the volume up on the gain test to what you usually listen to

 

[2loud4u 10+ year member]

take a pic of the side of your amp the settings are set at right now

cant no camera

But settings

Gain set with 0db test tone 50Hz 50 volts

Intelli q set to 0

Hpf set to 30hz

low pass set to around 80hz

phase set to 0

xover 12db

Gain set to master

also voltage does not drop under 14v

 

[mazdakid 5,000+ posts]

ok is it at like 1/4 gain, 1/2 gain, what?

 

[2loud4u 10+ year member]

to get 50v it is like in between 1/2 and 3/4 closer to 3/4

 

[Immacomputer 10+ year member]

Check the polarity with a 9v battery. You may have accidently wired the coils out of phase from each other.

If that doesn't do anything, set the gains by ear using music. Multimeters can be very deceptive.

 

[2loud4u 10+ year member]

The polairty with a 9v battery how can I tell?

 

[bamaboy 5,000+ posts]

dmm gain FTL, just set it by ear

 

[2loud4u 10+ year member]

yeah.

Just set it with a -3db 50hz test tone and went for a drive.

Poped in 36 late night tip and it got loud!!

It shook my head so much I could not read the display on my deck woot woot it is ugly anyways lol

Checked it during late night tip and it was hitting around 38v on the speaker terminals.

So she has alittle room left to go for sure.

Tomorrow when it is light out I am going to let it rip and tune it buy ear.

The sub is still brand new reconed quad stiff so it will take alittle to break that baby in.

Getting better.

 

[Immacomputer 10+ year member]

The polairty with a 9v battery how can I tell?

Take a 9v battery and put the positive wire to the sub onto the positive terminal of the battery and then the negative wire to the negative terminal. The sub should move out when you do this. If it doesn't move (I'm pretty sure even an MT should move) then you may have them out of phase. After switching the polarity of one coil, try it again and see what happens. If it now moves out, you're good to go. If it moved out from the start, try setting your gain by ear instead of a dmm.

The only time I use a dmm is when I have to get two amps to put out the same power. I will set the first amp up by ear and then measure it with a dmm then I use the dmm to set the second amp up using the same load.

 

[matrxx dude 5,000+ posts]

dmm gain FTL, just set it by ear

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