What did I do wrong? Why isn't it loud?

[jujumantb 10+ year member]

also, if your HU has a phase feature, switch from 180 - 0 or vice versa to check.difference should be dramatic

no.... all that does is switch the phase of that entire channel in comparison to the cabin speakers. (he needs to change it in comparison with one sub to the other) Wont do much at all especially with factory speakers.

 

[Megalomaniac 5,000+ posts]

'in phase' is when the subs both are working together (both move in and out together)
'out of phase' is when one moves out when the other moves in, effectively cancelling eachothers waves out.

since i only have 1 sub it shouldnt even matter then?

 

[squeak12 10+ year member]

17 volts...you sure you calculated that right?

 

[mikeyboc 10+ year member]

Take it to a shop.

subs and amp > joo

 

[Justinw303 10+ year member]

lol @ mikey.

My total output should be 600 watts @ 2 ohms, which is 34.64 volts. So when testing one of the channels I should get half of that, or 17.32. And I have to get the gains past 3/4 to get 17.

 

[wilzyx 5,000+ posts]

i got that you should be setting it at ~34.5 volts to push 300w rms to each sub.

edit: oops, too late

 

[psych0ticnemes1 5,000+ posts]

i had them and only got loud ported... sealed didnt do it for me

 

[jujumantb 10+ year member]

since i only have 1 sub it shouldnt even matter then?

Nope. But its important to define what is "in phase" with what. In this case, he have been talking about one sub being in phase with another sub, but it can also be important to have, say, your sub 'in phase' with your midbass (if they share a crossover point). Basically, whenever two speakers play the same frequencies, you want them to be in phase. Although this second case is not nearly as important as having your two subs in phase. (if you have two subs)

 

[squeak12 10+ year member]

Do you have your DMM at AC voltage and playing a tone? Also, if its 300 watts its not at 2 ohm its now at 4 ohm so 300 x 4 = 1200 Same as 600 x 2

 

[Justinw303 10+ year member]

Do you have your DMM at AC voltage and playing a tone? Also, if its 300 watts its not at 2 ohm its now at 4 ohm so 300 x 4 = 1200 Same as 600 x 2

For me to get 34 volts, the gain would be **** near maxed out... Is that safe?

EDIT: Plus, I did the same formula with my setup to come up with the number 20, and my setup pounds compared to this.

 

[squeak12 10+ year member]

If your headunit has a low RCA output, there is no problem with a maxed out gain. I dont like to use the voltage gain setting method. I just do it by ear and look at excursion. It hasnt failed me yet.

 

[jujumantb 10+ year member]

If your headunit has a low RCA output, there is no problem with a maxed out gain. I dont like to use the voltage gain setting method. I just do it by ear and look at excursion. It hasnt failed me yet.

yeah, IMO there is no reason for any of this "dmm o-scope 1.21 gigawatts super gain setting" techniques for 99% of us. As long as you know what clipping sounds like, its easy to set the gain by ear.

 

[Justinw303 10+ year member]

Well, I'm playing with someone's elses toys, so I'm a little careful.

Alright, can I get a double check on that 34 volt suggestion?

I mean, MY sistem gives me 400 watts @ 4 ohms, which is 40 volts. However, I tested each channel at 20 volts, and it sounds fine, with great excursion. Any higher and it sounds a little clipped.

 

[wilzyx 5,000+ posts]

For me to get 34 volts, the gain would be **** near maxed out... Is that safe?
EDIT: Plus, I did the same formula with my setup to come up with the number 20, and my setup pounds compared to this.

if your head unit has a sub output, make sure its at like +5 or +10 before you set your gains.

 

[mtdewelf 10+ year member]

if you've got everything(power,ground,rca's etc) ran then just take it to a shop, pay them alittle and have them check it. probably about 20-40bucks if you just walk in and are like, "hey i just had a diff shop set this up and think it's screwy" explain that you will give them ALL your business if they can prove it's screwed up and fix it. worth a shot.