I'd try and narrow the vent and make it taller to yield the same x-sectional area. 3cm ain't bad if you're not pumping it at loud volumes. But if you want to make a dance club in your bedroom, enlarge the vent.
At the 90 bend, I'd make a 45 followed by a few cm and another 45. Add up all three sections to get the total length. Google around to see what people do and what the rules of thumb are. There is a commonly accepted aspect ration for a slot port, but I can't remember what it is.
At the 90 bend, I'd make a 45 followed by a few cm and another 45. Add up all three sections to get the total length. Google around to see what people do and what the rules of thumb are. There is a commonly accepted aspect ration for a slot port, but I can't remember what it is.
An externally hosted image should be here but it was not working when we last tested it.
That is at 100W input power, which is probably way more than I'll use. I have two amplifiers, one old Yamaha at 2x52W and my HK3490 at 2x120W.
..and? continued...
well you were looking at the length required and the means of calculating the length of the port. I did both. The corner is not that important, you can leave it the way it is or use some cove molding there to smooth out the corner a bit.
It seems like 26m/sec is a "magic" velocity to stick to (or about 2.3% of the speed of sound). Can't recall where I got the number, but it's stuck in my brain...you're well within that number (14m/sec is approximately 1.24% of the speed of sound)
So using a 4" (10 cm) diameter vent isn't suitable? (well ok, a rectangular equivalent of a 10.52 cm diameter vent) The only concern might be the aspect ratio, but the total area will not be the issue. If the total area of the vent is not respected, then it must be lengthened.
well you were looking at the length required and the means of calculating the length of the port. I did both. The corner is not that important, you can leave it the way it is or use some cove molding there to smooth out the corner a bit.
It seems like 26m/sec is a "magic" velocity to stick to (or about 2.3% of the speed of sound). Can't recall where I got the number, but it's stuck in my brain...you're well within that number (14m/sec is approximately 1.24% of the speed of sound)
So using a 4" (10 cm) diameter vent isn't suitable? (well ok, a rectangular equivalent of a 10.52 cm diameter vent) The only concern might be the aspect ratio, but the total area will not be the issue. If the total area of the vent is not respected, then it must be lengthened.
Yeah, well WinISD already provided me with the right port length. I was just unsure how to do since I hade to make a 90 degree turn on the slot port.
I could probably find some kind of tube suitable for a port, but I think a slot port would be easiest if the aspect ratio isn't a problem.
slot ports are good...
Rullknufs,
I calculated an equivalent port area as using an (approximate) 4" actually 10.52 cm) diameter tube with length of 70cm. I haven't found references to the aspect ratio of slotted ports, but the basic idea is as I stated. With a velocity of about 1.25%, there is no issue with the port itself. There may be an issue with the square edge of the interior wall of the port. Anything that could be done to smooth the port entrance would help.
Rullknufs,
I calculated an equivalent port area as using an (approximate) 4" actually 10.52 cm) diameter tube with length of 70cm. I haven't found references to the aspect ratio of slotted ports, but the basic idea is as I stated. With a velocity of about 1.25%, there is no issue with the port itself. There may be an issue with the square edge of the interior wall of the port. Anything that could be done to smooth the port entrance would help.
fastbike, thanks.
Someplace I have "the Loudspeaker Design Cookbook" and was planning on looking for it.
Rullknufs: I was thinking something like this....(see attached image). Perhaps Mr. Dlugos could suggest if the vent should be reduced by 9 mm in length to make up the "height" of the 1/2 round molding. If you make the enclosure of Baltic Birch ply, you can machine it
, and if you're in Norway, why not? It should be very inexpensive....
Someplace I have "the Loudspeaker Design Cookbook" and was planning on looking for it.
Rullknufs: I was thinking something like this....(see attached image). Perhaps Mr. Dlugos could suggest if the vent should be reduced by 9 mm in length to make up the "height" of the 1/2 round molding. If you make the enclosure of Baltic Birch ply, you can machine it
, and if you're in Norway, why not? It should be very inexpensive....Attachments
Agreed. And working his current job, has funds. I don't think he has discovered women yet.
dave
Good observation Dave.
come on guys, he lives in Sweden and is on his folks' internet, so I'd wager he might know more about women than any of us did at his age - he's just investing his money in other areas
and is probably well practiced at left hand mousing?
is that code
Comeon geezers!
Well, I don't think you should buy women (not prostitution, but I guess you see my point). As they say, it's the thought that counts
Niklas - sorry 'bout that - I was just jesting that I doubt you hadn't "discovered" anything yet, but rather you might chose other venues for those pursuits / discussions - I should have used "time" rather than "money"
and one way or another, both sides of "transactions" pay
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