Dumb Box Building Questions

[electricashman]

Re: Re: edge round-overs

There's a thread in this forum, probably in the loudspeaker section, by somebody who did a thesis on diffraction effects. The work was basically a rehash of work published in the 1950s that has been subsequently published in a couple of texts.

I have a BIG interest in dispersion and defraction can anyone remember the user's name for that thread, I did a search but alot comes up.

I was thinking a full sphere box might be good for some frequencies but for low frequiencies wouldent you loose alot of efficiency.

Well, putting your sub in the corner at the roof of a room you have maximum efficiency, but it will sound too boomey and colored, I guess the sphere will have no coloration but Im also guessing it will require alot more power for low frequency.

I dont want to get off topic so if any one can help me find that thread that would be great...Ill continue to search...

Edit: spelling

 

[navin]

to really make a dent in difraction one has to do more than half round (1/2") the edges. that does little in my experience. one has to curve the baffle like Thiel does in the CS 3.5/3.6 etc..

my 2 cents.

cheers
Navin

 

[DocP]

Re: Re: Re: edge round-overs

I have a BIG interest in dispersion and defraction can anyone remember the user's name for that thread, I did a search but alot comes up.

http://www.diyaudio.com/forums/showthread.php?s=&threadid=4816&highlight=cabinet+AND+design

looking at it again, there is less detail here than I thought I remembered. I'll try to find the reference to that original work from the 50's but I'm moving house so most of my books are in boxes at the moment and are likely to stay that way for quite a while. 🙁

I was thinking a full sphere box might be good for some frequencies but for low frequiencies wouldent you loose alot of efficiency.

I can't remember in detail at the moment, but I think there were problems with the sphere, not least the fact that you have to deal with the nightmare acoustics inside the thing.

DocP
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[planet10]

Re: Re: Re: Re: edge round-overs

PaulV's Baffle Diffraction Simulator

dave

 

[electricashman]

thanks guys, Ill come back in afew days, alot of reading to do....

 

[navin]

hi this is comment is an offshoot of my earlier questions....(read them under "lots of questions").

Wonder how Thiel build their baffles so thick (refering to CS 3.6) and well tapered. I intend to try and copy their technique but would appreciate tips.

their baffle looks layered and obviously the inner baffle layers have larger cut outs to prevent tin can noises. it seems complicated but I am game. any tips here?

regards
navin

 

[planet10]

their baffle looks layered and obviously the inner baffle layers have larger cut outs to prevent tin can noises. it seems complicated but I am game. any tips here?

Have a look at the Stacks or the Coneheads at Andy Graddon's site. Maybe he will chime in with some tips.

dave

 

[navin]

will do.

he has already decided to help me with my FIRST series XO.

Oh Andy do please be gnetle 🙂 This is my first time! 🙂

Regards
Navin

 

[Redeye]

Lessons learnt so far on this project, number one :

Don't get the timber merchant to cut the panels for you. That the panels weren't quite the right size was much less of a problem than the fact that there wasn't a right angle to be found on any of them. Grrrrrrrrrrr........ I'm now trying to find a way to make a decent set of panels out of the stuff they did + the offcuts. Hopefully I'll figure it out....... I'm REALLY glad I'm doing this pair as a test before I start my powered studio monitors. Nevermind, all part of life's rich tapestry I guess......