I think that MJK sheets are unit agnostic, you just need to say what you are using.
In the case of the Spawns, the designer thinks in imperial, just be glad he designs them at all.
In any of the paid plan sets you get whatever conversion you need, and a suitable bribe can go a long ways with any of the free plans.
Personally i work in a mix of units, Chris works in metric so i output drawings in mm for him, he then measures the material at hand and adjusts -- 18mm typically ranging from something like 17.7 to 18.6mm so far. Sometimes he runs into sheets that differ in thickness over the same sheet.
dave
In the case of the Spawns, the designer thinks in imperial, just be glad he designs them at all.
In any of the paid plan sets you get whatever conversion you need, and a suitable bribe can go a long ways with any of the free plans.
Personally i work in a mix of units, Chris works in metric so i output drawings in mm for him, he then measures the material at hand and adjusts -- 18mm typically ranging from something like 17.7 to 18.6mm so far. Sometimes he runs into sheets that differ in thickness over the same sheet.
dave
Apparently our construction industry. Instead of switching to the decimal system with the advent of hand held calculators, they waited for ones that did fractions.
Dunno, ask these folks: DAO 201-21: COMMERCE METRIC CONVERSION
GM
Hi Dave,
Since I set my mind the Kirishima and and I really don't know anything about speakerdesign and horns I am not comfortable with continuing trying to do the conversion myself (and then once built find out it isn't as good as it can be).
Please let me know what we can work out for a 'suitable bribe'
Jock
If you don't like the units, change them. if it says 1*in, replace it with 2.54*mm or vis versa. Let the program do the comversions. BTW, all of the math is in MKG.
Bob
An update to the planset... http://p10hifi.net/FH/downloads/SpawnHorn-v2-planset-070412.pdf
A minor update to all the plans, and -- thanx to a donation by Jocjaruba to diyAudio and a pledge to frugal-horn.com -- a set of 18mm drawings for Kirishima.
dave
A minor update to all the plans, and -- thanx to a donation by Jocjaruba to diyAudio and a pledge to frugal-horn.com -- a set of 18mm drawings for Kirishima.
dave
Haven't Nasa done that a couple of times with rather disappointing results?
But I fully accept that one shouldn't look a gift horse in the mouth.
i can't get the Sd definition/unit/value to change. i end up with say an 800square inch Xsection instead of cm2/m2.
what am i doing wrong? i can't see the equation anywhere on the worksheet that defines the maths for Sd. its not a major problem converting, its just time consuming when you make a mistake.
its not that i'm ungrateful etc, its just very confusing when you've got things like Xmax in MM, VAS in litres then lbs and inches. once again wouldn't mind so much if i could get sketchup to display feet and inches in terms of a decimal instead of fractions as i can just switch between the value using sketchup instead of having to convert.
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Sketchup
Window>Model Info>Units>decimal.
You can move back and forth in a given sketch, i.e. not fixed at start.
Google is your friend as well.
Window>Model Info>Units>decimal.
You can move back and forth in a given sketch, i.e. not fixed at start.
Google is your friend as well.
thanks for that, i tried googling it but never got an answer as simple as that. that will speed things up.
Select the entire entry i.e. Sd=20.15*in^2 and replace it with Sd=130*cm^2
(type a period to get the subscript -- S.d will give you what you want.)
Bob
After a quick email to Dave, I decided that whilst waiting for my Fostex's to arrive in NZ, I would have a play with the design to see if I could make this work with a 3 inch Peerless 830986 driver. From the specs, I wasnt holding out much hope, but I have these in a BLH for the FE87E (I know, but they sound wonderful in this enclosure), so having a quiet day on Sunday, thought that I would throw one together to get a feel for the cabinet. A couple of hours later I had the cabinet built and glueing, now here comes the first of a number of errors, firstly, being in a rush to appear busy so that I didnt have to mow the lawns, I selected 13mm MDF instead of the 18mm that was stacked next to it, I made all the cuts and started glueing and when I came to the last two pieces, noticed my mistake, having come this far, I decided what the hell and carried on, then came my second mistake I glued the baffle on without the felt, what else can go wrong? Well, I placed the cabinet in my room and hooked it up (not expecting much to be honest) and fired it up. Well, what can I say? These baby's go deep! as deep as the same speakers in the FE87 BLH, but with a lot more punch. I will need to go back and re-make them, but with the correct thickness of material and felt. These are quite a forgiving design, but will be relegated to my study as they have little WAF!!!!
I will complete a full and proper build thread, as I think that much can be done with this enclosure design.
Thanks Dave
I glued the baffle on without the felt, what else can go wrong? Well, I placed the cabinet in my room and hooked it up (not expecting much to be honest) and fired it up. Well, what can I say? These baby's go deep! as deep as the same speakers in the FE87 BLH, but with a lot more punch. I will need to go back and re-make them, but with the correct thickness of material and felt. These are quite a forgiving design, but will be relegated to my study as they have little WAF!!!!I will complete a full and proper build thread, as I think that much can be done with this enclosure design.
Thanks Dave
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Fringy75,
Looks like you're having fun
Hi Zia.
I took that basic design of the Kongō and very unscientifically changed the sizing to work for the Peerless 3" driver (Dave would kill me if he could get near me I think)
When working on the re-sizing, i looked for similarities between the 3 sizes for the Fostex FE126En, FE166En, and FE206En, and noted that the enclosure for the FE206En was twice the size of the one for the FE126En, then I reduced the size of the Kongō by a third!, so internal width is now 98mm. The one on the right is the BLH for the FE87E I am having a great time just playing
so internal width is now 98mm. The one on the right is the BLH for the FE87E
That is one anoxeric cabinet! Hope there are no cats or kids near the speakers - these were born tippy!
I am having a great time just playing
That's what matters!
That is one anoxeric cabinet! Hope there are no cats or kids near the speakers - these were born tippy!
Thats for sure, and no to cats or kids, just shame that the wife doesnt like them
That's what matters!
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