It'll go straight into the Calhoun we've done for the FE207E. Only adjustment required is to lengthen the twin slot-vents to 100mm each.
Take the attached with a large pinch of salt guys -MathCad is limited in what it can do with twin throats / vents in this configuration. That said, I see no reason why it shouldn't work pretty well for a simple & fun box.
Take the attached with a large pinch of salt guys -MathCad is limited in what it can do with twin throats / vents in this configuration. That said, I see no reason why it shouldn't work pretty well for a simple & fun box.
Attachments
>I see the plan for "Lyeco LY802F BVR DoubleHorn" on your site. This is the plan?
Kind of. The revised version which will accept the Pioneer is currently on the 'to draw' list.
>I can't seem to locate the plan on the Dave's spawn family site. Where can I find the plan?
You won't find the plan for the most excellent reason that it hasn't been drawn yet either...
Sorry. There are quite a few on the aforementioned list & my timing is not all it could have been: I've unfortunately innundated Dave with a bunch of new cabinet ideas recently, right at the same time as I revised all of the existing BVR boxes -he has to fit this in between paying work!
On a brighter note, the 207 Calhoun (as yet un-named) by nature is a very simple box, and I certainly make no pretence about it being otherwise, or even what inspired it, so you should be able to build it even without plans. No kidding. You guys will probably want to burn my effigy when I tell you what it is.
1) Take 1 of Fostex's suggested bass-reflex cabinets for the FE206E (not the 207) and reposition the driver to the middle of the front baffle.
2) Instead of using the normal port, add two Calhoun style flared vents above and below this box, each 381mm tall. The strike plates can be built in steps, or single angled pieces. Assuming 18mm material is used, you should now have a cabinet a total of 1584mm tall.
3) At the back of the top and bottom panel of the reflex chamber, leave a gap the full internal width of the cabinet, and 10mm deep (front to back). Add, in front of these slots, a piece of material the width of the cabinet, and 82mm tall, so you have two slot vents 100mm long firing into their own flared waveguides.
4) Line the chamber as you would a regular reflex cabinet, and finally, add a fairly deep triangular piece as seen in the throat of some of the BVR cabinets, which should hopefully reduce some of the cross-talk that would exist between the two vents. See the very rough attached drawing. There are plenty of other possible ways of doing this, perhaps with bracing or similar, so let your imagination run riot. There's also lots of potential for adjusting the tuning by making one slot-vent a greater CSA than the other etc. That's pretty much how I view these cabinets: a quick, simple bit of fun, that's also a bit different from the norm and with loads of potential for tuning to taste. I reckon they'll sound pretty decent too, although hardly the last word in high fidelity. Probably ideal for a cheaper unit like the Pioneer. Bass reflex with a twist.
Hope this is of use
Scott
PS -sorry about the terrible drawing quality -I know it looks awkward when seen like this, but in reality, it should be quite a neat looking box.
Kind of. The revised version which will accept the Pioneer is currently on the 'to draw' list.
>I can't seem to locate the plan on the Dave's spawn family site. Where can I find the plan?
You won't find the plan for the most excellent reason that it hasn't been drawn yet either...
Sorry. There are quite a few on the aforementioned list & my timing is not all it could have been: I've unfortunately innundated Dave with a bunch of new cabinet ideas recently, right at the same time as I revised all of the existing BVR boxes -he has to fit this in between paying work!On a brighter note, the 207 Calhoun (as yet un-named) by nature is a very simple box, and I certainly make no pretence about it being otherwise, or even what inspired it, so you should be able to build it even without plans. No kidding. You guys will probably want to burn my effigy when I tell you what it is.
1) Take 1 of Fostex's suggested bass-reflex cabinets for the FE206E (not the 207) and reposition the driver to the middle of the front baffle.
2) Instead of using the normal port, add two Calhoun style flared vents above and below this box, each 381mm tall. The strike plates can be built in steps, or single angled pieces. Assuming 18mm material is used, you should now have a cabinet a total of 1584mm tall.
3) At the back of the top and bottom panel of the reflex chamber, leave a gap the full internal width of the cabinet, and 10mm deep (front to back). Add, in front of these slots, a piece of material the width of the cabinet, and 82mm tall, so you have two slot vents 100mm long firing into their own flared waveguides.
4) Line the chamber as you would a regular reflex cabinet, and finally, add a fairly deep triangular piece as seen in the throat of some of the BVR cabinets, which should hopefully reduce some of the cross-talk that would exist between the two vents. See the very rough attached drawing. There are plenty of other possible ways of doing this, perhaps with bracing or similar, so let your imagination run riot. There's also lots of potential for adjusting the tuning by making one slot-vent a greater CSA than the other etc. That's pretty much how I view these cabinets: a quick, simple bit of fun, that's also a bit different from the norm and with loads of potential for tuning to taste. I reckon they'll sound pretty decent too, although hardly the last word in high fidelity. Probably ideal for a cheaper unit like the Pioneer. Bass reflex with a twist.
Hope this is of use
Scott
PS -sorry about the terrible drawing quality -I know it looks awkward when seen like this, but in reality, it should be quite a neat looking box.
Attachments
Just seen the first pass drawing of the new box (provisionally named 'Chang' for some reason... ) for checking. How they can be drawn so fast is beyond me. Expect an initial airing very soon.
Greg (as in GM): I beg your forgiveness for doing a design like this.
My only defense is that they're 'fun' boxes. Pretty much as easy as stuffing the driver in a regular quick vented box, & they'll certainly sound a bit different.
) for checking. How they can be drawn so fast is beyond me. Expect an initial airing very soon. Greg (as in GM): I beg your forgiveness for doing a design like this.
My only defense is that they're 'fun' boxes. Pretty much as easy as stuffing the driver in a regular quick vented box, & they'll certainly sound a bit different. 
Not up on the site yet, but here is Chang (Greg, you can't not build it now )
http://p10hifi.net/tlinespeakers/FH/download/Chang-207e-NBVR-170707.pdf
Scott, i'll need the sim for it...
dave
)http://p10hifi.net/tlinespeakers/FH/download/Chang-207e-NBVR-170707.pdf
Scott, i'll need the sim for it...
dave
GM said:Why, what have I said/implied to warrant it? I mean I'm a platinum card carrying member of the KISS club. Anyway, taking a vent's flared end correction to extremes is right in step with my motto of 'if some is good, then too much is just enough'.
Amen.Sorry Greg, probably a misinterpretation on my part. It was in reference to your advice about avoiding placing two throats directly opposite each other due to potential 1/2 wave resonance issues between them. That's why I thought the triangular deflector between them might be a good idea. I've taken your advice re rapid end-correctrions to heart, as you can see...
Drat. Sorry Dave, I forgot to attach them (207 & B20) to my QC email response. You have mail.
planet10 said:Not up on the site yet, but here is Chang (Greg, you can't not build it now
http://homepage.mac.com/tlinespeakers/FH/download/Chang-207e-NBVR-170707.pdf
Scott, i'll need the sim for it...
dave
thanks very much, exactly what I needed. Will go over it in detail.
gychang
Scottmoose said:Just seen the first pass drawing of the new box (provisionally named 'Chang' for some reason...
You guys are great, fast, all these names Harvey etc..., feel rather honored for a drawing to be named after me... Now only if that lottery has my name on it...
gychang
planet10 said:Not up on the site yet, but here is Chang (Greg, you can't not build it now
http://homepage.mac.com/tlinespeakers/FH/download/Chang-207e-NBVR-170707.pdf
Scott, i'll need the sim for it...
dave
Dave and Scott:
Here is my version of "Chang-Descendant of Calhoun" from sketchup.
Basically I changed the stepped slats to 45degree angle cut (I can do this on my circular saw...
) I understand triangle piece is somewhat arbituary. Dave put all the dimensions that I will use including the critical rear vent. I am still not sure how much the polyfill to use, ?bottom half of the chamber? or just carpet padding on top and bottom?thanks, soon as my zigmohornet is done, then this is next in line...
I am shocked at how relatively simple this build will be.
gychang
Attachments
Lining the top, bottom & one side-wall should be sufficient. Make sure you don't obstruct the vents.
>I am shocked at how relatively simple this build will be.
Simple is often a good thing, as GM observed. I was surprised myself when I first started playing with this geometry at how well it appears to work, at least on a simulation, & I can't see any reason why it shouldn't do well in practice.
>I am shocked at how relatively simple this build will be.
Simple is often a good thing, as GM observed. I was surprised myself when I first started playing with this geometry at how well it appears to work, at least on a simulation, & I can't see any reason why it shouldn't do well in practice.