Bought 2 RE audio 18 SX's....... and....

[snfsh79077 10+ year member]

Double check the chart with the equation I gave you. Also don't turn your ssf too low, put it around 26-27hz if your box is 29-30hz.

equation:

sqrt (watts * impedance)

example:

sqrt (1200 * 1) = 34.64 volts

another thing I noticed is you have each sub going to the amp separately each at a 1ohm load. This makes me think that your amp is running at a 2 ohm load instead of a 1 ohm load.

 

[guacho80 10+ year member]

Just a quick & cheap suggestion: get a new baffle for 2 15's, get you SX reconed with 15'' basket and cones, make sure they are dual 4 ohms, you should expect a much better efficiency and output, and it wouldn't cost/take a lot of work to do.

 

[jamesw 10+ year member]

this is not hard at all. your running a hifonics amp they barely do rated power if that. Set your gain with a DMM. I dont know why your having so much trouble to realize this I think a number of people have already said the same thing. Your clipping the crap out of your subs.

 

[Cameron_B 10+ year member]

where are you guys getting 10 cubes?

In the video, with his measurements, it is clearly over 12 cubes.

If it is 12 cubes their is absolutely not enough port, but this should not make the woofers overheat to where they are melting dustcaps....especially with that amplifier. These 2 subwoofers should take this amp at minimal clipping and not melt caps.

 

[Bassman999 10+ year member]

where are you guys getting 10 cubes?
In the video, with his measurements, it is clearly over 12 cubes.

If it is 12 cubes their is absolutely not enough port, but this should not make the woofers overheat to where they are melting dustcaps....especially with that amplifier. These 2 subwoofers should take this amp at minimal clipping and not melt caps.

I took the actual measurement and subtracted 1.5" every direction exept depth where i subtracted .75" then I guestimated .2 each sub displacement, and after port somewhere around 10.3-10.7 ft^3 making it tuned to around 36 hz. I could be way off though, as I cannot see the internal shape of the box.

 

[Cameron_B 10+ year member]

Whoops sorry forgot to take wood thickness.

Anyways with the small front chamber it should still be in the ~12 area

 

[knowledgestick 10+ year member]

Double check the chart with the equation I gave you. Also don't turn your ssf too low, put it around 26-27hz if your box is 29-30hz.equation:

sqrt (watts * impedance)

example:

sqrt (1200 * 1) = 34.64 volts

another thing I noticed is you have each sub going to the amp separately each at a 1ohm load. This makes me think that your amp is running at a 2 ohm load instead of a 1 ohm load.

when you check the subs, each channel with a metre they come up as 1ohm.

each subwoofer is at 1ohm, so are you saying that the amplifier is at a 2ohm load because of that ?

that would make sense as to why the subwoofers arnt pounding very hard unless the level is all the way up because they arnt getting that real 1300 rms each, they are getting around half of that if that is the case.

I have seen pictures and diagrams with the rockford wiring setup program and mine does not look like that setup at all, i will have to try wiring them differantly and see if that works in-terms of amplifier power/level.

but also i have to agree with the last poster, who stated that my box is well over 10 cubic feet.. i have to stand by that aswell.. but maybe me having to turn the gain up so high, because the amplifier is at a 2ohm load is what is creating the exessive over-heating.

I will try to re-wire them in fashion with one of the diagrams from the rockford site.

Also i will then, adjust the gain via the chart i have and metre.

i will do this once i get home from picking up my gf //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif lol

 

[Bassman999 10+ year member]

12-16 square inches per cubic foot is the medium for a slot port. If he says his box is 14 cubes then it would need 168 square inches minimum...if it is 10 cubes which is more likely then it will need a minimum or 120 square inches. Either way port area is still to small for those subs.
with that being said fix what I stated before and you will see a noticeable difference. You box is still not correct though

edit:

a rough design of a box that is 20" high x 39" wide x 28" deep with 111 sq inches of port area tuned to 29hz is only 8.6 cubic feet before sub displacement and w/o bracing. Meaning that your is probably not even 10 cubic feet...

I come up with 100^2 port area not 111^2 port, and if it was actually tuned to 30 hz it would be way longer that 13, more like 27" long.

 

[knowledgestick 10+ year member]

Double check the chart with the equation I gave you. Also don't turn your ssf too low, put it around 26-27hz if your box is 29-30hz.equation:

sqrt (watts * impedance)

example:

sqrt (1200 * 1) = 34.64 volts

another thing I noticed is you have each sub going to the amp separately each at a 1ohm load. This makes me think that your amp is running at a 2 ohm load instead of a 1 ohm load.

could you please link the propper wiring for this setup/amp ? sorry i dont think i understand how to get it at a 1ohm load, just use 1 of the channels and wire it up so they are in series ?

when both of the subwoofer channels are read now with the metre, they read 1ohm.

this is at the amplfier, you can see it in my last video.

 

[Bassman999 10+ year member]

when you check the subs, each channel with a metre they come up as 1ohm.
each subwoofer is at 1ohm, so are you saying that the amplifier is at a 2ohm load because of that ?

that would make sense as to why the subwoofers arnt pounding very hard unless the level is all the way up because they arnt getting that real 1300 rms each, they are getting around half of that if that is the case.

I have seen pictures and diagrams with the rockford wiring setup program and mine does not look like that setup at all, i will have to try wiring them differantly and see if that works in-terms of amplifier power/level.

but also i have to agree with the last poster, who stated that my box is well over 10 cubic feet.. i have to stand by that aswell.. but maybe me having to turn the gain up so high, because the amplifier is at a 2ohm load is what is creating the exessive over-heating.

I will try to re-wire them in fashion with one of the diagrams from the rockford site.

Also i will then, adjust the gain via the chart i have and metre.

i will do this once i get home from picking up my gf //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif lol

hifonics brutus is a single mono channel. it does have 2 sets of outputs to make connection easier they are the same channel the load is across both of them just as if there was only one set and they were both in it. I hope that makes sense.

 

[knowledgestick 10+ year member]

I took the actual measurement and subtracted 1.5" every direction exept depth where i subtracted .75" then I guestimated .2 each sub displacement, and after port somewhere around 10.3-10.7 ft^3 making it tuned to around 36 hz. I could be way off though, as I cannot see the internal shape of the box.

as you can see where the port is, and i measure down it is very deep, for a good distance back, and across and then i have some even smaller space underneathe the amplifier... i knew it wasnt under 10 cubic feet, im not THAT retarded.

i will try the propper wiring, with propper gain settings and see how that helps.

could somebody please link the propper wiring diagram ? thanks guys.... i appreciate everybodys patience with me very much.

-andrew

 

[snoopdan 5,000+ posts]

don't feel too bad, my Sx 18's get stinky too after awhile when I put 5k to em //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif They're not meant to be some supersub, they're mid grade to begin with.

I just use em as spares anyways //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[snfsh79077 10+ year member]

when you check the subs, each channel with a metre they come up as 1ohm.
each subwoofer is at 1ohm, so are you saying that the amplifier is at a 2ohm load because of that ?

that would make sense as to why the subwoofers arnt pounding very hard unless the level is all the way up because they arnt getting that real 1300 rms each, they are getting around half of that if that is the case.

I have seen pictures and diagrams with the rockford wiring setup program and mine does not look like that setup at all, i will have to try wiring them differantly and see if that works in-terms of amplifier power/level.

but also i have to agree with the last poster, who stated that my box is well over 10 cubic feet.. i have to stand by that aswell.. but maybe me having to turn the gain up so high, because the amplifier is at a 2ohm load is what is creating the exessive over-heating.

I will try to re-wire them in fashion with one of the diagrams from the rockford site.

Also i will then, adjust the gain via the chart i have and metre.

i will do this once i get home from picking up my gf //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif lol

yes your amp is running at a 2 ohm load which from the amps specs is 1300rms then factor in that they are slightly overrated so your probably giving your subs 500rms each clipped bad. Your subs are dual 2 ohm and you won't be able to run them at 1 ohm

I come up with 100^2 port area not 111^2 port, and if it was actually tuned to 30 hz it would be way longer that 13, more like 27" long.

Yes HIS box has 100^2 of port area. However I took his dimensions and designed a normal rectangle box with a slot port and after port displacement I came out with 8.6 cu ft tuned to 30hz. He stated that his box is tuned to 29-30hz so I designed an enclosure that would be around what his should be.

 

[knowledgestick 10+ year member]

yes your amp is running at a 2 ohm load which from the amps specs is 1300rms then factor in that they are slightly overrated so your probably giving your subs 500rms each clipped bad. Your subs are dual 2 ohm and you won't be able to run them at 1 ohm


Yes HIS box has 100^2 of port area. However I took his dimensions and designed a normal rectangle box with a slot port and after port displacement I came out with 8.6 cu ft tuned to 30hz. He stated that his box is tuned to 29-30hz so I designed an enclosure that would be around what his should be.

my subwoofers are dual 4 ohm i had them designed so i could run them at 1ohm.

 

[cx-7heaven 10+ year member]

You have to decide what ohm you are actually at. Earlier, you said each sub is 1 ohm, now you say ther are dual 4... pick one. If they are dual 4, wire each positive to positive and neg to neg on each sub, then you have 1 pos and 1 neg coming from each sub, wire pos to pos and neg to neg, and you have a TOTAL 1 ohm load, which is what your amp wants to see for max power.