On another forum, I read a post concerning the curved cabinets having a
problem with audible resonation. Has anyone here that has used this cabinet
noticed this? I am just about to finish up a project using the .75^3 cab.
Below is the quote
"I built two pairs of speakers (cherry and maple) over last Christmas using the 0.38 cu. ft. curved boxes. Yes, they do audibly resonate."
Never argue with an idiot. They drag you down to their level, then beat you up with experience.
next question to ask is the driver the right size? did he shoehorn a powerful bass driver in it? is it sealed?
I know the biggest problem that happens is the baffle can rattle. Only 4 bolts hold it. he might fix the noise with 5 dollars worth of weather stripping. We had a thread on this problem. see link for the fix.
Thanks Philip,
The OP didn't include the particulars of the build, just the resulting issue.
Mine will be a sealed cab with the RS225. I have plenty of the P.E. dynamat clone around so I will just be a little MORE anal and cover all of my bases before any final glue up.
Never argue with an idiot. They drag you down to their level, then beat you up with experience.
yeah it is a good idea that is a lot of driver. for a small box. make sure to stuff with polyfill or fiberglass that will help it also. if you look at my avatar that box is a .75 cu ft pe maple square box with a 2.25 inch solid maple baffle attached. tons of glue to attach the baffle sprayed the inside with pe cascade stuffed it with fiberglass. The driver is a scanspeak 23w 9.5 inch sub. box has a little bit of movement but you can't not hear it without putting your ear on it. look at my album for the build.
On another forum, I read a post concerning the curved cabinets having a
problem with audible resonation. Has anyone here that has used this cabinet
noticed this? I am just about to finish up a project using the .75^3 cab.
I built a pair of RS180 Modula MT's in the 0.75 curved enclosures. There is very little enclosure resonance.
On a related topic, Danny Ritchie of GR Research is using some of the smaller PE enclosures for one of his kits, and he has found the 0.38 and 0.50 enclosures are quite a bit smaller than advertised.
He also recommends cutting out the part of the center brace that would reflect the woofer's back signal. I did this with my Modulas.
yes a few sites have mentioned this. on my scanspeak 23w build with the .75 cu foot cabinet I added a lot of room by making a 2.25 inch baffle. You can increase the cabinet with a piece of mdf . under cut it enough to allow trim on it and cut a rectangle on the inside. it is like a picture frame.
I built a speaker using the 0.75 cuft MTM curved side cabinets. I think that the side walls of the cabs could be improved by adding a little dampening material (e.g. mass loaded vinyl, etc). but would not characterize this a "resonance problem". I think that the front baffle should definitely be glued on when you are finally satisfied with the results, since (as other posted have mentioned) the four corner bolts are not sufficient to hold on the baffle at high sound volumes.
Overall I am very happy with these cabs and they look great.
All cabinets are slightly larger than advertised with the exception of .5 ft³ cabinets which are .494 ft³ for the traditional and .477 ft ³ for the curved sided. The traditional is 1.2% undersized and the curved sided is 4.6% undersized. Although the .5 ft³ curved sided is undersized (slightly) it is certainly in the ballpark and would not change any aspect (f3, Qtc etc.) of a box/speaker combination, therefore we feel it isn't necessary to change how we advertise them.
Due to the shape of the curved sided cabinets it is almost impossible to measure within ± 5% using a ruler. Accurate measurement would require geometry and or calculus, another method would be to fill the enclosure with some material (small beads, popcorn, sand, water), empty the contents into a basic shape enclosure and measure the amount
Finally, we are working on getting all Dayton cabinet drawings up on the website. The drawings indicate the box volume so this may help, but even with the detailed drawings it is difficult to derive internal volume of the curved sided cabinet.
Feel free to pass comments, suggestions, or questions directly to us here at Dayton Audio. My email address is: richtATSIGNdaytonaudio.com
As always, we thank you for your patronage!
Rich Taylor
Brand Manager
Dayton Audio
MANUFACTURED DAYTON CABINET INTERNAL VOLUME
TRADITIONAL ft³
0.25 TWO-WAY 0.281
0.38 TWO-WAY 0.387
0.5 TWO-WAY 0.494
0.75 TWO-WAY 0.780
0.75 MTM 0.763
1.0 MTM 0.999
1.0 SUB 1.084
2.0 SUB 2.084
3.0 SUB 3.122
On a related topic, Danny Ritchie of GR Research is using some of the smaller PE enclosures for one of his kits, and he has found the 0.38 and 0.50 enclosures are quite a bit smaller than advertised.
I have the .25 and .38 cabinets and they are both slightly larger than noted to take in account the space occupied by the driver and crossover.
Well the resonace issues proved to be non-issues. A little Dynamat
on the side walls was more than adequate.
This issue involves mounting the baffles permanatley.
It may just be the 2 cabs I have, but when I was gluing the baffles on this weekend, using a two part epoxy, I noticed that there was no squeeze out.
This baffled me because I was pretty liberal with the epoxy, and expected some excess after tightening the screws. I did a little investigation with the second cabinet and found the baffle recess to be at least a 1/8" deeper than the edge of the baffle that should make contact
What is the baffle suppose to "grab" onto?
Are the screws and a little weather stripping suppose to do the job?
Beware
Before gluing, measure the recess and baffle edge and make sure that these two parts will actually meet and make contact
Never argue with an idiot. They drag you down to their level, then beat you up with experience.
on my .75 cu ft square box the baffle sits flush. if you have a table saw cut a shim to fit on the lip pre glue it then glue the baffle to it.
If I remember you are sealing a rss225 in this box. I would want that to sit flush if I am gluing it to be permanent. It is a lot of driver. another trick is use construction paper and wood glue even a cardboard strip and wood glue. it is easy to cut to fit with a straight edge and a razor and it will hold the glue. If you use a shim or card board and the screws it should level and hold you should see squeeze out of glue.
I think I may have fixed the problem on the second cab, but was not aware of the gap on the first cab, untill after I had glued up. I have used several of the P.E. rectangular cabs, where the baffle sits flush on the rabbet. I think P.E. should have a note on there web page, and for sure in the product box, addressing this issue.
Still at wits end on what to do for the first cabinet.
Last edited by mace; 06-24-2008 at 11:26 AM.
Reason: wrong info
Never argue with an idiot. They drag you down to their level, then beat you up with experience.
I assume you have hole in the baffle for the rss225 turn the speaker one 1 side this should make 1 baffle cabinet edge parallel to the table it is resting on. take a glue like the one in the first thumbnail photo and fill the one line/gap that is level with the table
the following pictures are the bartop of solid maple the center piece is 10 by 1.5 by 4 feet it shrank over the last year leaving a gap. It took about 1 quart of wood glue thinned with a little water and in a bottle with a good squeeze tip to fill the gaps 3 years later it is still good.
you will need to turn the cabinet on all four sides at least 1 time and wait at least 6 hours for the glue to set for each side. the good thing is it is not a lot of physical work and it is low cost. phil
P.E. curved cabinet ???
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Originally Posted by mace
me because I was pretty liberal with the epoxy, and expected some excess after tightening the screws. I did a little investigation with the second cabinet and found the baffle recess to be at least a 1/8" deeper than the edge of the baffle that should make contact
