15" of pure pleasure

[Green Machine Mowing]

Re: 15" of pure pleasure

also i was thinking of doing all 1.5" is that way overkill?? would i be better off bracing well with 3/4"?

[philiparcario]

Re: 15" of pure pleasure

My 12 inch nht1259's sealed are 2 inches all around. I am a heavy box for sub advocate. Unless you are doing an IB all different rules then

[blktre]

Re: 15" of pure pleasure

Im using 3/4" plywood with a double baffle. Its more than what i want to pick up. My sealed box outside dimensions is 22 1/2" squared. By the time i add in bracing the double baffle, and the driver, im around 4.36 cubic feet.

[Green Machine Mowing]

Re: 15" of pure pleasure

i was thinking of adding some big caps to the psu of the 500 watt o-audio to help with transients, ect. is this worth my time and money? is it goig to tax the transformer on start up? if i do do it what caps are reccomended?

heres a pic from avs forum, i belive the 2 caps on the left are the ones that i would need to tie into

there are more pics, if youd like to see them.

[Green Machine Mowing]

Re: 15" of pure pleasure

if you look, there are a thick red and black wires going from the power supply area to the amp section, could i put a cap between these or inline of the positive?? assuming they are power positive and negative

[philiparcario]

Re: 15" of pure pleasure

you need to be careful those caps are 200v. you have a high voltage power supply. see if you can get a reading on the input to the caps. it should be after the rectifier. before the caps it should be dc and 150 volts or so. be careful this looks like a high voltage design. if it is use caps like 1200uf 200volts not 10000uf 63 volts.

[philiparcario]

Re: 15" of pure pleasure

i see it is a switching power supply I don't know how to work with them like i do linear. you need some one to step up.

[Green Machine Mowing]

Re: 15" of pure pleasure

thanks for all of your help on this so far phil i really appreciate it. i dont have yet ive just been thinking about this sub build and thought that that might be a pretty cheap and easy mod, but how often am i really going to be sucking thoes stock caps dry? probly not that often

its probly not the best idea for some one with little electronics experience to go after a brand new $250 amp with his soldering iron.

i read a thing on avs forum where a guy bench tested one of these and said that due to an internial limiter, it would hit 500W on a transient but if he slowley worked up to it he could only get to about 450W, and could see the waves were starting to get rounded off by the limiter, i think that it may be the soft clip feature starting to kick in, or perhaps a lacking psu and cap bank.

[eyekode]

Re: 15" of pure pleasure

If it honestly puts out 450w there is no reason to stretch for the extra 50w. Do a simulation to see the difference in SPL, it will not be noticeable. And if it actually does 500w transients? Awesome, it is a keeper.

[Green Machine Mowing]

Re: 15" of pure pleasure

If it honestly puts out 450w there is no reason to stretch for the extra 50w. Do a simulation to see the difference in SPL, it will not be noticeable. And if it actually does 500w transients? Awesome, it is a keeper.

yah, u are right

so box size around 3ft^3 or larger??

if u scroll up on this page, you get pics,scroll down, there are the o audio specs, then what he bench tested it at. looks like 459 Wrms ar 80 Hz.

[Green Machine Mowing]

Re: 15" of pure pleasure

how about recomendeitions (sp?) for bracing, i was thinking 2 mdf shelf style braces with holes drilled in them

pics or renderings would be great.

im going to do a 1 1/2" baffel and 3/4" sides, so good bracing will be vidal.

[philiparcario]

Re: 15" of pure pleasure

thanks for all of your help on this so far phil i really appreciate it. i dont have yet ive just been thinking about this sub build and thought that that might be a pretty cheap and easy mod, but how often am i really going to be sucking thoes stock caps dry? probly not that often

its probly not the best idea for some one with little electronics experience to go after a brand new $250 amp with his soldering iron.

i read a thing on avs forum where a guy bench tested one of these and said that due to an internial limiter, it would hit 500W on a transient but if he slowley worked up to it he could only get to about 450W, and could see the waves were starting to get rounded off by the limiter, i think that it may be the soft clip feature starting to kick in, or perhaps a lacking psu and cap bank.

Yeah I would leave it alone. It should have enough power.

[philiparcario]

Re: 15" of pure pleasure

yah, u are right

so box size around 3ft^3 or larger??

if u scroll up on this page, you get pics,scroll down, there are the o audio specs, then what he bench tested it at. looks like 459 Wrms ar 80 Hz.

go bigger then 3.3 cu ft. I went back and re read you have the rss390hf-4 Most of us that have built it prefer 3.5 to 4 ft. you can get away with 3/4 sides and a 1 1/2 baffle. use shelf braces with holes cut in.

A cube of 21 inches on the outside with a 1.5 baffle and .75 sides is 4.126 cu ft. but 2 braces 1 sub and 1 amp are at least .6126 feet. That gives you a 3.5 cu ft inside. a few people have had trouble with that size. if you make the cube on the outside 22 inches. the inside is 22 - 1.5 = 20.5 the sides 22 - 1.5 = 20.5 the top and bottom then it is 22 - 2.25 19.75 the baffle and rear that is 8300 cu inches 20.5 times 20.5 times 19.75 . 8300 cu in is 4.8 cu ft take out .8 for the braces the amp and the sub gets you to 4 cu ft. lots of room for any additional braces etc. and the outside only went from 21 cubed to 22 cubed. you will need a set of braces at 3 and 9 oclock from the baffle to the rear use wooden closet rod. this stops front to rear flex. plus the 2 shelf braces. plus 5 lbs of poly-fil or fiberglass. seal the inside with this rubber paint from home depot it is safe and non toxic. it is a latex based rubber does not stink. paint the inside of the box. when the box is built . see thumbnail

[Green Machine Mowing]

Re: 15" of pure pleasure

22" cubed, sounds good, what does that rubberised paint stuff from hd do? is it worth $40??

5 lbs of stuffing seems like alot, i put 1 lb in each of my lyras, which were 1.5 ft^3 and it was fairley dense, but its certanly doable.

[Green Machine Mowing]

Re: 15" of pure pleasure

i realized today that a 22" cube is quite large, could i put a few aperiodic vents in there to bring the size down a little bit??

also, am i crazy to try to flush mount this thing? i think getting and accurate measurement of a 15" driver going to be trickey, i certanly dont have any calipers that size, and ive heard that they are a pain to get in and out that way. so are the astetics enough better that its worth all of the work?