No Problem Revvy, design away. I'd like to see what you come up with.
Well some may be interested in a "bottom heavy" sub, as mentioned I did have a store bought sub [sounds like iodine and a fine product] but again the 30hz low bass pours out of these things.
And the tuning is right on: Peak20 -Valley30 - Peak40 Post #52. This was done with a dry fit, semi built box, clamped together (the 1st mock up box, years ago).
So anyway.....here's a few construction tips for someone interested in a Iso tunnel.
You have to careful to make the tunnel long enough, check that out thoroughly before you get started. I came up with 5" - no less!
I laminated 2 - 3/4" pieces together 3 times + the 3/4" baffle = 5".
Don't forget to add in the front baffle board.
***7 pieces total****
To get started, cut the outer rings first, I went 9.25" OD for an 8" woofer, which needs a 7" ID hole/tunnel. (I hope you get that)
The 1st photo, don't toss the scrap pieces ~ that's the holder for when you cut the inside hole, just clamp it back around the disk, this is much safer also.
The second photo ~ looks good right? Too bad they are not candles. Once you get your pieces cut, start laminating them together. I did use a couple of nails to line them up while the glue was drying.
Oh btw, I doweled a piece of hardwood in, bottom/front, do reduce nicks (-;
Well some may be interested in a "bottom heavy" sub, as mentioned I did have a store bought sub [sounds like iodine and a fine product] but again the 30hz low bass pours out of these things.
And the tuning is right on: Peak20 -Valley30 - Peak40 Post #52. This was done with a dry fit, semi built box, clamped together (the 1st mock up box, years ago).
So anyway.....here's a few construction tips for someone interested in a Iso tunnel.
You have to careful to make the tunnel long enough, check that out thoroughly before you get started. I came up with 5" - no less!
I laminated 2 - 3/4" pieces together 3 times + the 3/4" baffle = 5".
Don't forget to add in the front baffle board.
***7 pieces total****
To get started, cut the outer rings first, I went 9.25" OD for an 8" woofer, which needs a 7" ID hole/tunnel. (I hope you get that)
The 1st photo, don't toss the scrap pieces ~ that's the holder for when you cut the inside hole, just clamp it back around the disk, this is much safer also.
The second photo ~ looks good right? Too bad they are not candles. Once you get your pieces cut, start laminating them together. I did use a couple of nails to line them up while the glue was drying.
Oh btw, I doweled a piece of hardwood in, bottom/front, do reduce nicks (-;
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So this is going pretty good; started it yesterday. I did have to run to a hardware store and pic up gallon of white primer for $12 and asked for 1 ounce of black tint, since I'm going black.
So building one and listening to one at the same time; the "other" box worked well with the 240w Dayton, (the auto-shut-off doesn't appear to work). I compared the Dayton with a similar 200w plate amp (competitor's), I think the Dayton won that comparison.
The other brand X plate amp had a variable phase knob, since I had a 60hz cd recording, it was easy to phase the satellites with the sub.
So building one and listening to one at the same time; the "other" box worked well with the 240w Dayton, (the auto-shut-off doesn't appear to work). I compared the Dayton with a similar 200w plate amp (competitor's), I think the Dayton won that comparison.
The other brand X plate amp had a variable phase knob, since I had a 60hz cd recording, it was easy to phase the satellites with the sub.
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I got some of them from bjorno crossed from others who have measured the drivers and averaged them.
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Hi,
The crucial points of the Ts parameters are very low Qts, low Fs and
modest Vas - point to a relatively heavy cone driver with a big magnet.
Consequently any isobaric arrangements are near pointless - always.
like I said ages ago, this is simply not a driver where isobaric works.
It works best one its own in 10L to 12L with a PR.
rgds, sreten.
The crucial points of the Ts parameters are very low Qts, low Fs and
modest Vas - point to a relatively heavy cone driver with a big magnet.
Consequently any isobaric arrangements are near pointless - always.
like I said ages ago, this is simply not a driver where isobaric works.
It works best one its own in 10L to 12L with a PR.
rgds, sreten.
Oh I think you might raise an eyebrow if you heard one, it's quite amazing actually.
I wish I kept the clamshell box for pics, that's really an easy build. I made two (2) I think, they were smaller and had a little more output. I did copy it on a excel file.
3 coats of paint today, more than I like to do with Latex. One more coat should do it.
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Hi Odougbo,
I've been messing with this for days. Then I came across the other "make a horn around the mcm's" thread... My design is so similar to epa's it's silly, just longer with one more segment and a similar choke at the start of the horn just like the TH design above.
I cannibalized some of epa and jbell's ideas and came up with this.
best,
rev.
I've been messing with this for days. Then I came across the other "make a horn around the mcm's" thread... My design is so similar to epa's it's silly, just longer with one more segment and a similar choke at the start of the horn just like the TH design above.
I cannibalized some of epa and jbell's ideas and came up with this. best,
rev.
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Very Nice! I love sneaky subs, "Oh look.. it's so cute" then BAM they kick you in the head.
I gotta get some of these mcm drivers.
I was just thinking most folks don't even know what they look like; huge magnets, over 6".
They have their limits since they are "soft suspension" e.g. if you try to break windows, or expect to listen to cannon fire and gun shots without some kind of protection, they won't hold up.
What I like about all this in a nut shell, they sound great at low volumes.
I had them cranking with music yesterday - very loud, deafening, no problems.
And the amp only got slighty warm.
I hope they don't stop making them ~~ ya never know.
They have their limits since they are "soft suspension" e.g. if you try to break windows, or expect to listen to cannon fire and gun shots without some kind of protection, they won't hold up.
What I like about all this in a nut shell, they sound great at low volumes.
I had them cranking with music yesterday - very loud, deafening, no problems.
And the amp only got slighty warm.
I hope they don't stop making them ~~ ya never know.
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this sim seems ok to me.Hi Odougbo,
I've been messing with this for days. Then I came across the other "make a horn around the mcm's" thread... My design is so similar to epa's it's silly, just longer with one more segment and a similar choke at the start of the horn just like the TH design above.
best,
rev.
have you converted it in to a plan?
Hi,
No. Stuff designed on a wing and prayer is not going to be better
than done properly. Claims of "amazing" are simply that, claims.
Its just dull you don't get it, it's a driver totally unsuited to isobaric.
rgds, sreten.
Sub #4
Sreten, tell us what do you really think, don't have to sugar coat it.
I know you are not a fan of isobaric and this design in general, but folks, it rocks the house and shakes the floor; in a HT and in a 2.1. The bass just pours out of these speakers, and sounds great at low levels.
It's a shame Sreten will never hear them (and I think he has a couple) and only going by....well, I really don't know where he's basing all the criticism.
It doesn't matter to me really, I have tried/build lots of subs, probably keep building them, maybe I'll find something better someday.
I would like folks to know, I didn't just build one, and now I think it's really cool. I have built 6 BR boxes, 2 clamshell and 4 tunnel boxes with this woofer. So I did put a lot of time-energy-thought into these. I did follow a long path, which lead me here.
Again, I don't know what would come close to this "budget project"; $30 per speaker (sale price) and a sheet of MDF.
Sreten, tell us what do you really think, don't have to sugar coat it.
I know you are not a fan of isobaric and this design in general, but folks, it rocks the house and shakes the floor; in a HT and in a 2.1. The bass just pours out of these speakers, and sounds great at low levels.
It's a shame Sreten will never hear them (and I think he has a couple) and only going by....well, I really don't know where he's basing all the criticism.
It doesn't matter to me really, I have tried/build lots of subs, probably keep building them, maybe I'll find something better someday.
I would like folks to know, I didn't just build one, and now I think it's really cool. I have built 6 BR boxes, 2 clamshell and 4 tunnel boxes with this woofer. So I did put a lot of time-energy-thought into these. I did follow a long path, which lead me here.
Again, I don't know what would come close to this "budget project"; $30 per speaker (sale price) and a sheet of MDF.
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Hi,
Who said I didn't like isobarics ? They are great for the right drivers,
and the right circumstances, they typically allow drivers to be used
for a case when the box for one driver is too big, you can halve it.
And a poor / pointless choice for the wrong driver, you keep saying
they are great going by ..... whatever. I have said the 30Hz vented
isobaric version has a box that is far too big with a big peak at 30Hz,
that the two drivers used normally in the same box will sound better,
go just as deep but avoid the peak, and go 6dB louder, effectively
quadrupling the apparent amplifier power over the isobaric as they
will also be 6dB more efficient.
Literally twice as good, its like having two of the isobarics.
Your right of not a fan of this "design" because it isn't one IMO,
it models very poorly, suggesting wrong design decisions, a more
thought out proper design has overwhelming advantages, done right.
You seem to be saying you can't see what's wrong with it .....
Do some modelling and you will soon see, isobaric with this driver
costs an extra driver and a beefier amplifier for no real purpose,
and you end up with silly small box sizes for the best performance.
rgds, sreten.
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