It is so much simpler to use plywood for the baffle and simply mount it on the front. No compound angles to bother with.
My box, pictured on #11 of this thread was very simple and straightforward. (In spite of the fact that I have no router and so had to make a compound baffle to recess the drivers). Also I am crap at woodwork,and the rear "plys" of the baffle are mdf. And yet they still look passable.
My box, pictured on #11 of this thread was very simple and straightforward. (In spite of the fact that I have no router and so had to make a compound baffle to recess the drivers). Also I am crap at woodwork,and the rear "plys" of the baffle are mdf. And yet they still look passable.
That’s exactly what I thought he was originally going to do with the quarter round molding, build a ledge on the inside edge to attach the baffle.
With a cone emitting the high frequencies I am guessing that diffraction is less of a problem than with a small dome, I should have made an internal ledge instead. I might make a new set of boxes for Philips AD/5061 drivers, and they look better rearmounted and then I really need a detachable front baffle.
I have a bunch of 100 microfarad caps made in West-Germany! I will try adding those as the drivers start to flap about probably due to signals below where the port is loading the driver say sub 60 Hz or so.
I really like to finish these and get back to my large open baffles, but things pops up, derailing my finishing touches...
I really like those boxes though, perhaps as tweeter, small midrange boxes.
I really like to finish these and get back to my large open baffles, but things pops up, derailing my finishing touches...
I really like those boxes though, perhaps as tweeter, small midrange boxes.
Well if I look at it from a strictly electrical point of view the 600 uF does nothing above 30 Hz and the cone flaps just as much as with no cap. At the other end 100 uF cuts in at 100 Hz or so.
Judging from the impedance graphs it looks like something in the order of 200-300 uF should work out. I have to measure accoustic response and listen as well. The cap also adds phase changes and that should change how the driver and port interact.
I will look into that thread, thanks for the information. Busy with work so progress will be slow, but hopefully steady.
Judging from the impedance graphs it looks like something in the order of 200-300 uF should work out. I have to measure accoustic response and listen as well. The cap also adds phase changes and that should change how the driver and port interact.
I will look into that thread, thanks for the information. Busy with work so progress will be slow, but hopefully steady.
I looked at the nearfield response of the cone. The ideal would be that the cap does not affect the cone output above the port dip or the port dip just cut away cone motions below the cone dip.
Below are the graphs the first is the original the second has the responses normalized to the capless response.
The 100 uF (Blue) cuts away to much. The brown-red-orange (600-500-400) has small effect on the cone output above 50 Hz but not much protection below that either.
The green at 200uF looks like a resonable compromise. I think I will try to measure and listen to 200 and 150uF to balance reduced cone flapping vs bass output.
Just to complicate matters, should I test an even smaller cap for cutting out deep bass then need to have the baffle step filter and peak trap reinstalled...
Below are the graphs the first is the original the second has the responses normalized to the capless response.
The 100 uF (Blue) cuts away to much. The brown-red-orange (600-500-400) has small effect on the cone output above 50 Hz but not much protection below that either.
The green at 200uF looks like a resonable compromise. I think I will try to measure and listen to 200 and 150uF to balance reduced cone flapping vs bass output.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Just to complicate matters, should I test an even smaller cap for cutting out deep bass then need to have the baffle step filter and peak trap reinstalled...
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Final thoughts.
Listening to tearing at the seams with Nathaniel Rateliff & The Night Sweats
The good
They sound surprisingly good for a 4" running solo.
Hindsights
I should have put ledges inside the long sides of the box and used glued them airtight that way, out of sight.
The gap could be filled with quarter molding, left as is or ornamented with brass rods of suitable diameter and lenght
I got a good lesson with filter design that graphs are useful but they do not tell the whole story by far. In the loudness range that they reside most of the time they sound better without the peak trap and baffle step. So I let them sound more strident the few times I play them loud. I have other speakers for that
Time to get the large open baffle speaker up and running.
Listening to tearing at the seams with Nathaniel Rateliff & The Night Sweats
The good
They sound surprisingly good for a 4" running solo.
Hindsights
I should have put ledges inside the long sides of the box and used glued them airtight that way, out of sight.
The gap could be filled with quarter molding, left as is or ornamented with brass rods of suitable diameter and lenght
I got a good lesson with filter design that graphs are useful but they do not tell the whole story by far. In the loudness range that they reside most of the time they sound better without the peak trap and baffle step. So I let them sound more strident the few times I play them loud. I have other speakers for that
Time to get the large open baffle speaker up and running.
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