Hello,
I see that in this document for the FE127 MLTL http://www.diyaudio.com/forums/attachment.php?s=&postid=843952&stamp=1139772600 that it says you can use standard shelving material to build this. Does this included those pine laminated shelving unit pieces you find at Home Depot or Rona?
Thanks.
I see that in this document for the FE127 MLTL http://www.diyaudio.com/forums/attachment.php?s=&postid=843952&stamp=1139772600 that it says you can use standard shelving material to build this. Does this included those pine laminated shelving unit pieces you find at Home Depot or Rona?
Thanks.
Thanks GM,
Thats what I was looking for, somebody with more experience than me to say yes.
With a bigger driver, will the pine sheets not be rigid enough to keep from vibrating? Could this be midigated by bracing or sandwitching something more rigid to it, or would it just be better to go to thicker birch plywood then?
Thats what I was looking for, somebody with more experience than me to say yes.
With a bigger driver, will the pine sheets not be rigid enough to keep from vibrating? Could this be midigated by bracing or sandwitching something more rigid to it, or would it just be better to go to thicker birch plywood then?
You're welcome!
I've used the 2 - 3 ft wide panels x 4 ft with an internal 'skin' of 1/4" no-void grade plywood and the same bracing scheme for dual 15" woofers as I would with 3/4" no-void grade plywood with no obvious vibration problems, i.e. can balance a ~square shoulder coin on end on its top and 'pound' away at ~live SPLs. The main thing is to use a solvent based, hard setting adhesive such as used in building construction.
Some folks just couldn't get enough of the butcher block 'look' back in the '70s.
GM
I've used the 2 - 3 ft wide panels x 4 ft with an internal 'skin' of 1/4" no-void grade plywood and the same bracing scheme for dual 15" woofers as I would with 3/4" no-void grade plywood with no obvious vibration problems, i.e. can balance a ~square shoulder coin on end on its top and 'pound' away at ~live SPLs. The main thing is to use a solvent based, hard setting adhesive such as used in building construction.
Some folks just couldn't get enough of the butcher block 'look' back in the '70s.
GM
Thanks again.
Its not that I am cheap, but I have no access to a table saw and good tools like that to build boxes with full sheets of birch ply. These shelving things seem like a good idea for a box. It looks like from some that you could even just fasten them together and you would have to do barely any cuts to achieve a BIB or an MLTL. I will have to see if dad has an extra circular saw kicking around when I go home next weekend to do some small straight cuts with.
Its not that I am cheap, but I have no access to a table saw and good tools like that to build boxes with full sheets of birch ply. These shelving things seem like a good idea for a box. It looks like from some that you could even just fasten them together and you would have to do barely any cuts to achieve a BIB or an MLTL. I will have to see if dad has an extra circular saw kicking around when I go home next weekend to do some small straight cuts with.
You bet!
Well, I am when I figure I can make it work well enough, so I've done a number of designs for folks using stock shelving boards, including the 127E IIRC. Indeed, my early tower designs (aka MLTL) I built back in the late '60s used a bunch of 1" x 12" x 48"cheap stock walnut paper veneered PB shelving boards a co-worker had laying around from a stillborn project. Back then, we often used whatever we could find 'on the cheap' that didn't audibly rattle/squeak. Round and square concrete or terracotta drain pipe was popular too, often costing us only the manpower to take it away from a construction site's scrap heap. Ditto left over concrete forming tubes (aka Sonotube), wood, wire, etc..
GM
Well, I am when I figure I can make it work well enough, so I've done a number of designs for folks using stock shelving boards, including the 127E IIRC. Indeed, my early tower designs (aka MLTL) I built back in the late '60s used a bunch of 1" x 12" x 48"cheap stock walnut paper veneered PB shelving boards a co-worker had laying around from a stillborn project. Back then, we often used whatever we could find 'on the cheap' that didn't audibly rattle/squeak. Round and square concrete or terracotta drain pipe was popular too, often costing us only the manpower to take it away from a construction site's scrap heap. Ditto left over concrete forming tubes (aka Sonotube), wood, wire, etc..
GM
I have built them and there's a thread I've tried to put all the
information in and hope that people will add to it.
http://www.diyaudio.com/forums/showthread.php?threadid=118857
As to the pine board butcher block stuff, I think it works well
in sizes larger than the MLTL as well. I've made the BIB with FE127e with that product and am happy with the results. There again, very minimal cutting on the glue up stock and the front/internal divider and back were cut from from some particle board shelving.
Those long cuts need a table saw.
My original GM MLTLs were made entirely from 2 ft particle board shelving and they are still in use. They have been torn down and rebuilt to try various tweaks over time: moving port position, adding removing suprabaffle etc.
This is perfect for getting some experience and not worrying too much about furniture. Particle board properties are close to ideal IMOH.
information in and hope that people will add to it.
http://www.diyaudio.com/forums/showthread.php?threadid=118857
As to the pine board butcher block stuff, I think it works well
in sizes larger than the MLTL as well. I've made the BIB with FE127e with that product and am happy with the results. There again, very minimal cutting on the glue up stock and the front/internal divider and back were cut from from some particle board shelving.
Those long cuts need a table saw.
My original GM MLTLs were made entirely from 2 ft particle board shelving and they are still in use. They have been torn down and rebuilt to try various tweaks over time: moving port position, adding removing suprabaffle etc.
This is perfect for getting some experience and not worrying too much about furniture. Particle board properties are close to ideal IMOH.
Hi Lon
Did you build the DIYAudio Reference MLTL monopoles:
or the Zilla MLTLs?
Did you build the DIYAudio Reference MLTL monopoles:
An externally hosted image should be here but it was not working when we last tested it.
or the Zilla MLTLs?
An externally hosted image should be here but it was not working when we last tested it.
http://www.zillaspeak.com/fostex127eSSB.asp
These use standard sized pine from home depot. I don't have a saw either - just a hand saw to cut holes.
I have not compared my more simple design to the mltl or a BIB but i will say i enjoy the 127e driver even tho it is a bit skitzo in the treble.
These use standard sized pine from home depot. I don't have a saw either - just a hand saw to cut holes.
I have not compared my more simple design to the mltl or a BIB but i will say i enjoy the 127e driver even tho it is a bit skitzo in the treble.
GM said:
I have the particle board baffle , middle and back on the BIB
and particle board all over the MLTL. I have a mostly plywood build
of the Harvey.
Have I tried others? No. My builds are pretty rare. The properties of the particle are most dead without the mess of MDF. But since I want to fine tune the MLTL, GM-style what do you suggest?
A quick gander at the sheet price of baltic birch even at the
budget store was $70 per 4 x 8 sheet. And the top one looked bowed. :-/
The other thread also asked about a holey brace in the MLTL but I got no replies on that.
Yes, if true particleboard, then the panels will be well damped, but the downside is they tend to 'suck the life' (micro detail) out of a wide BW driver, especially small ones, though by the same token can damp down some of a high Q driver's 'ringing'.
Fine tune? Like what? Assuming you used good construction techniques, then once you optimize internal damping and vent length to a 'FR' driver MLTL there's nothing left but wire size and any driver tweaks.
Yeah, it's been several years since I last priced 19 mm BB ply and it was $61 for a 5x5 ft sheet IIRC, so factor in inflation and the recent high rise in transportation costs and I'm surprised it's not more.
Well, assuming you used 3/4" particleboard for such a small pipe, then the loss of net Vb probably makes it not worth the effort, though I'd add a screw brace to mass load the driver:
GM
Fine tune? Like what? Assuming you used good construction techniques, then once you optimize internal damping and vent length to a 'FR' driver MLTL there's nothing left but wire size and any driver tweaks.
Yeah, it's been several years since I last priced 19 mm BB ply and it was $61 for a 5x5 ft sheet IIRC, so factor in inflation and the recent high rise in transportation costs and I'm surprised it's not more.
Well, assuming you used 3/4" particleboard for such a small pipe, then the loss of net Vb probably makes it not worth the effort, though I'd add a screw brace to mass load the driver:
GM
Attachments
Thanks for all the help you give.
I was wondering how a brace of any sort could push and pull at the same time when attaching the speaker to the front. It's still sort of a mystery to me when looking at the holey brace designs.
Is the pressure screw technique described someplace? I can see
the t-nut but not exactly how the pressure is applied
But back to materials, I am not wedded to particle board. And I'm
at the point of making the design again because of the wear and tear on cabinet. I've had these several years now.
So to get those micro effects or just to get a better look, if I used the construction technique from the BIB: particle board front and back and ply or shelf stock board on the sides would it make any difference besides the looks?
Construction includes chamfering the cutout and flush mounting.
I've also used some moulding to round the edge of the cabinet
but that is to hide some rough edges more than anything. The round edge look of wood is visually pleasing.
I was wondering how a brace of any sort could push and pull at the same time when attaching the speaker to the front. It's still sort of a mystery to me when looking at the holey brace designs.
Is the pressure screw technique described someplace? I can see
the t-nut but not exactly how the pressure is applied
But back to materials, I am not wedded to particle board. And I'm
at the point of making the design again because of the wear and tear on cabinet. I've had these several years now.
So to get those micro effects or just to get a better look, if I used the construction technique from the BIB: particle board front and back and ply or shelf stock board on the sides would it make any difference besides the looks?
Construction includes chamfering the cutout and flush mounting.
I've also used some moulding to round the edge of the cabinet
but that is to hide some rough edges more than anything. The round edge look of wood is visually pleasing.
You're welcome!
The 'holey' brace or screw adjustable tensioner merely puts a bit of positive pressure against the driver/baffle interface to better couple it to the cab and keep it from moving around on its pliable gasket joint, i.e. improving its electro-mechanical efficiency.
The pressure is applied by turning the screw clockwise and once an audible point of diminishing returns is reached, anymore runs the risk of damaging the driver. In retrospect, considering your material choice, adding at least a front/rear dowel brace above/below the driver to maximize the tensioner's efficiency seems a good tweak.
The 'holey' brace requires either a predetermined pre-load (not a good plan IMO) or a small gap between it and the driver to allow shims since over time it will probably ideally need additional shims.
Some have argued/proven that this form of driver mass loading is self defeating in that the frequencies damped are actually distortion, euphonic though it may be, but speaker design is all about trade-offs and while many tube based systems have a bit too much for my 'tastes', 'dead' sounding speakers is a bit too much in the other extreme, so as always it's a personal preference sort of trade-off, like MDF or other low MOE material Vs BB ply or other high MOE one, i.e. any combo can be made to work well, just some work well without having to do extensive tweaking for the various types of speakers normally discussed/recommended here.
Folded horns require their own unique damping Vs rigidity trade-offs, so I don't recommend using them as a guide for designing other types of cab alignments. Anyway, my BIB MDF and/or PB panel substitutions were for back, bottom if flush against the floor/rear wall and whichever side was flush against a wall if corner loaded, i.e. no air gap due to baseboards/whatever.
GM
The 'holey' brace or screw adjustable tensioner merely puts a bit of positive pressure against the driver/baffle interface to better couple it to the cab and keep it from moving around on its pliable gasket joint, i.e. improving its electro-mechanical efficiency.
The pressure is applied by turning the screw clockwise and once an audible point of diminishing returns is reached, anymore runs the risk of damaging the driver. In retrospect, considering your material choice, adding at least a front/rear dowel brace above/below the driver to maximize the tensioner's efficiency seems a good tweak.
The 'holey' brace requires either a predetermined pre-load (not a good plan IMO) or a small gap between it and the driver to allow shims since over time it will probably ideally need additional shims.
Some have argued/proven that this form of driver mass loading is self defeating in that the frequencies damped are actually distortion, euphonic though it may be, but speaker design is all about trade-offs and while many tube based systems have a bit too much for my 'tastes', 'dead' sounding speakers is a bit too much in the other extreme, so as always it's a personal preference sort of trade-off, like MDF or other low MOE material Vs BB ply or other high MOE one, i.e. any combo can be made to work well, just some work well without having to do extensive tweaking for the various types of speakers normally discussed/recommended here.
Folded horns require their own unique damping Vs rigidity trade-offs, so I don't recommend using them as a guide for designing other types of cab alignments. Anyway, my BIB MDF and/or PB panel substitutions were for back, bottom if flush against the floor/rear wall and whichever side was flush against a wall if corner loaded, i.e. no air gap due to baseboards/whatever.
GM
My positioning is less than ideal WRT baseboards (see post 2 up
from here.)
The problem is getting driver height close to ear level while making the
overall length on the side panels (no false bottom but just panel legs)
cut to fit around baseboard heaters. My baseboard heaters here at the apt are pretty high and deep as well.
Back to the MLTLs, I'm going to recut some pieces and get some more
practice before getting any expensive wood.
The final question I have on this shelving topic is:
If the width is increased to where no cutting if the 2 ft shelves is needed at all and the volume is adjusted by narrowing the
sides, will the change defeat the calculations that Greg has made?
Stock shelving is 23 3/4 plus or minus 1/64 wide and 10 3/8 deep plus or minus depending on production run.
One goal I go for is to help first time builders with no tools. Conceivably, stock shelving front/backss with sides made of other stock width in solid wood could be trimmed with just a hand saw and straight edge or saw board setup.
from here.)
The problem is getting driver height close to ear level while making the
overall length on the side panels (no false bottom but just panel legs)
cut to fit around baseboard heaters. My baseboard heaters here at the apt are pretty high and deep as well.
Back to the MLTLs, I'm going to recut some pieces and get some more
practice before getting any expensive wood.
The final question I have on this shelving topic is:
If the width is increased to where no cutting if the 2 ft shelves is needed at all and the volume is adjusted by narrowing the
sides, will the change defeat the calculations that Greg has made?
Stock shelving is 23 3/4 plus or minus 1/64 wide and 10 3/8 deep plus or minus depending on production run.
One goal I go for is to help first time builders with no tools. Conceivably, stock shelving front/backss with sides made of other stock width in solid wood could be trimmed with just a hand saw and straight edge or saw board setup.
?? Anyway, you don't want any typical speaker building wood materials anywhere near space heaters.
WRT calcs, I assume you mean for the driver and vent, so no since the former is based on a complex ratio between cab height and CSA and the latter on net Vb and the distance between the driver and vent Vs the bottom of the cab.
Frankly, there's so many available widths in a standard 48" length, seems to me virtually all 'FR' driver MLTLs can be fudged to work without doing any cutting other than with a hole or jig saw and a short metal guide with two clamps to hold it.
GM
WRT calcs, I assume you mean for the driver and vent, so no since the former is based on a complex ratio between cab height and CSA and the latter on net Vb and the distance between the driver and vent Vs the bottom of the cab.
Frankly, there's so many available widths in a standard 48" length, seems to me virtually all 'FR' driver MLTLs can be fudged to work without doing any cutting other than with a hole or jig saw and a short metal guide with two clamps to hold it.
GM
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.