Hi!
I've built a couple of kits before, but I've just started designing and building a speaker from scratch. I’m cheating a bit though. Ganesha, my speaker, will use the same drivers and have roughly the same volume as the open-source SB Acoustics Bromo kit. So, it wouldn’t surprise me if I end up with similar port dimensions and a comparable crossover.
I've just glued up the cabinet and started to learn how to measure drivers... and I'm a bit lost so thats why I'm here. 🙂
Cheers,
Jan
I've built a couple of kits before, but I've just started designing and building a speaker from scratch. I’m cheating a bit though. Ganesha, my speaker, will use the same drivers and have roughly the same volume as the open-source SB Acoustics Bromo kit. So, it wouldn’t surprise me if I end up with similar port dimensions and a comparable crossover.
I've just glued up the cabinet and started to learn how to measure drivers... and I'm a bit lost so thats why I'm here. 🙂
Cheers,
Jan
Welcome to diyAudio :^)
Hard to get excited about a translam build. Its only advantage is to be able to do exotic shapes and yours isn’t that.
There are more than a few translam builds here, that is where you will get assistance.
dave
Hard to get excited about a translam build. Its only advantage is to be able to do exotic shapes and yours isn’t that.
There are more than a few translam builds here, that is where you will get assistance.
dave
Oh Dave… ❤️
Thats were you are wrong. Not only is it one of the simplest ways of building something that isn’t a standard box. It also one of the few ways to expose that beautiful birch ply edge.
Thats were you are wrong. Not only is it one of the simplest ways of building something that isn’t a standard box. It also one of the few ways to expose that beautiful birch ply edge.
If that is what you want.
Note that when you use BB in this direction it is not nearly as stiff/strong (ie you are using it inthe wrong dimension) so instead of 18mm walls you will probably need 35mm. Factor that in. It will also need bracing which should be 90° to the plies.
The shape/roundover at the front should be much larger if you want it to really be useful and not just pretty.
dave
Note that when you use BB in this direction it is not nearly as stiff/strong (ie you are using it inthe wrong dimension) so instead of 18mm walls you will probably need 35mm. Factor that in. It will also need bracing which should be 90° to the plies.
The shape/roundover at the front should be much larger if you want it to really be useful and not just pretty.
dave
Both drivers are not physically phase flat in this arrangement, so the cabinet has to be tilted backwards a bit, overshooting the audience.
A slightly recessed top driver will suffice, if the smart crafted design allows.
These things mingle into the overall phase response, which will become even more troublesome with second order (and plus) crossover filters.
A frequency fissure ("Thou shall not pass!") might occur.
A slightly recessed top driver will suffice, if the smart crafted design allows.
These things mingle into the overall phase response, which will become even more troublesome with second order (and plus) crossover filters.
A frequency fissure ("Thou shall not pass!") might occur.
I don’t have 35. The baffle is 30 and the smallest portion is 24. Probably not enough? I’ve got a bracing layer between the drivers. What do you think about that?
What would you say an appropriate radius would be? The current radius is 55mm.
Attachments
How much recess are we talking about approximately? Either way tilting it is likely easier to get right.
What is it with this configuration that doesn’t make it phase flat? Most cabinets do not have recessed tweeters or are tilted -right? Most cabinets are bad?
Can you expand on this. The current bracing is still just ply oriented in the same direction. Are you saying that that won’t be enough?
Not very useful.
Because it is translam the only part you are bracing is that piece. All the pieces need to feel the brace. So it/they need to be vertical
How big is the box intended to be?
dave
Drive four 10mm wooden rods through the walls (longitudinal)? Do you think that will work?
I’ve seen the effect a metal rod can have when the wood starts to move (cracks), but wood maybe?
I’m fully aware that I’m solving problems I’ve created, but that’s fine. It’s fun and educational.
You wouldn't try to tilt the whole cabinet either?
Just fix it in the crossover?
Well, the Bromo kit isn't tilted and you are using the same drivers... So it would seem to be fine.
While cross-bracing is a proven way to ameliorate wall vibration, with your translam design you also have the freedom to select wall thickness, which is another way to do it. With thicker walls you will need less cross-bracing to achieve the same result. You can use a combination of the two.
Also note that you can incorporate your bracing into the layers without making them separate parts as you show in your last pic. Kind of like a macro version of 3D printing. Conceptualise it as a solid, then separate into layers.
Also note that you can incorporate your bracing into the layers without making them separate parts as you show in your last pic. Kind of like a macro version of 3D printing. Conceptualise it as a solid, then separate into layers.