vrollin Posted August 11, 2012 Author Report Share Posted August 11, 2012 post you meserments and ill work out what you have, but as i said, it not excact, it normaly going the be give or take 1hz, the yellow line is the length of port in this drawing Ahh, now I see what was being said reg measured from the centre of the angle, and here I was mind running wild thinking parts of the port wouldn't do anything and what not. So what your saying with this is that all the red area counts towards port volume, however in terms of calculating the length of the port to obtain port volume, you just measure from the centre of the angle? Same as running a line straight down and working out the volume for the triangle shaped part of the port and adding it to the square/rectangle shape part of the port...? Im just gunna rebuild one of the boxes with the slot port on the side the same volume as specified by the focal spec sheet and see how it goes, I feel i should be getting a hell of alot more out of my subs considering the cabin size.... Link to comment Share on other sites More sharing options...
john253a Posted August 11, 2012 Report Share Posted August 11, 2012 that is correct for sure, are you just building it to there specs or your own, as most companies recommend a smaller port then you should run, and with it being inside the ute, if there is any port noise you will here it for sure Link to comment Share on other sites More sharing options...
vrollin Posted August 11, 2012 Author Report Share Posted August 11, 2012 Another question, while nutting out design, will any old paint do inside the port, or does it need to be gloss or anything special? Or am I thinking into it too hard? Link to comment Share on other sites More sharing options...
john253a Posted August 11, 2012 Report Share Posted August 11, 2012 anything is fine, just try to keep it smooth, to assist in keeping the efficiency up, but sometimes a rough/dimpled Finnish works better, but best stick to flat and smooth i normally use spray putty/primer (all in 1) in a can leave it to dry and sand smooth, then just paint it with what ever i have, the putty/primer also assist in covering the end-grain, for a flawless finish Link to comment Share on other sites More sharing options...
vrollin Posted August 11, 2012 Author Report Share Posted August 11, 2012 that is correct for sure, are you just building it to there specs or your own, as most companies recommend a smaller port then you should run, and with it being inside the ute, if there is any port noise you will here it for sure The boxes internal, are just on 25L without sub displacement or port volume taken out. Focals specs recommend the same port 7" x 25" for 15, 25 and 30L boxes, so was just going to build the same port volume in a squared off shape. What port volume would you recommend for a 25L box to get around the 35hz mark? Focal quote 20L with its port to 40hz and 30L with its port to 33Hz, so I figured being the box I will build is 25L it will equate to around 35-36Hz, no maths here just guesstimating... Link to comment Share on other sites More sharing options...
john253a Posted August 11, 2012 Report Share Posted August 11, 2012 what is the measurements of you box, metric is fine, Link to comment Share on other sites More sharing options...
Jessica Posted August 11, 2012 Report Share Posted August 11, 2012 I know you are limited on space, and any port you put in the box, whatever the volume of the port you have to subtract from the volume of the box. So, have you oconsidered doing an external port so you keep you volume and still get your port? Rest in peace, walled 87 accord build log 03' Corolla build with AA Mayhem inside. My super random youtube channel and terrible camera work. Wiring comparison by CaptainzPlanetz Wire and fuse guide by Guest SyKo13 Link to comment Share on other sites More sharing options...
vrollin Posted August 11, 2012 Author Report Share Posted August 11, 2012 Externally, 480mm wide, depth top 145mm, depth bottom 250mm, height 320mm. Have been running with 16mm mdf for all panels. Link to comment Share on other sites More sharing options...
vrollin Posted August 19, 2012 Author Report Share Posted August 19, 2012 Diving in, started building a box with a slot port, not sure if it will work so just an experiment at this stage, just wish I had some better tools for the build, I literally have to cut using the back step as a work bench so keep making small fuck-ups... Link to comment Share on other sites More sharing options...
vrollin Posted August 20, 2012 Author Report Share Posted August 20, 2012 Progress so far, box looks really rough in the pics, actually aint that rough in person. Hopefully, finesse a couple of things on it tomorrow, trim it and maybe even test it, will probably do that the day after due to fumes..... If all works as planned, will build another one Didnt even give it time to dry to take the photo... Link to comment Share on other sites More sharing options...
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