Hi! I'm in the process of planning out Anthology speakers and have a friend who takes CnC orders. The idea is to make the speakers fully out of 18mm plywood or alternatively just plywood front baffles and rest from MDF. The usage of a precise CnC router allows for some very precise roundovers - so I'm thinking how to best make use of it. I have planned something like this:
Which has a 30mm roundover in the woofers and at the top, 60mm roundover in the mids and it goes to 90mm roundover on the tweeter, with an organic transition between these steps. This not only looks incredibly cool on my opinion, but also seems to be the best possible option apart from maybe doing spherical tops as well (but that's much harder). Am I correct in my assumption? Is this a good idea at all or do I run into unforseen resonances with such a design?
Another thing is that this reduces the wall thickness in several places. Should I glue strips at the corners to increase the thickness there?
And lastly, should I round the corners inside the cabinets with putty or something similar? I will be damping the entire thing with acoustilux polyester fabric (or rather a similar product) with 10mm felt beneath that and bitumin mats all over the cabinets.
Thanks in advance!
Which has a 30mm roundover in the woofers and at the top, 60mm roundover in the mids and it goes to 90mm roundover on the tweeter, with an organic transition between these steps. This not only looks incredibly cool on my opinion, but also seems to be the best possible option apart from maybe doing spherical tops as well (but that's much harder). Am I correct in my assumption? Is this a good idea at all or do I run into unforseen resonances with such a design?
Another thing is that this reduces the wall thickness in several places. Should I glue strips at the corners to increase the thickness there?
And lastly, should I round the corners inside the cabinets with putty or something similar? I will be damping the entire thing with acoustilux polyester fabric (or rather a similar product) with 10mm felt beneath that and bitumin mats all over the cabinets.
Thanks in advance!
Why don't you look into these? You would have to change construction. I have used them a couple of times.
https://mouldings.com/collections/radius-corners
This is 2" 3/4 you can go up to 6" There are also several other options than what I used.
Rob 🙂
https://mouldings.com/collections/radius-corners
This is 2" 3/4 you can go up to 6" There are also several other options than what I used.
Rob 🙂
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Adding a little more roundover is probably fine in most cases. But adding a much larger roundover could make things worse. The crossover designer has measured the actual drivers in the actual baffles and taken into account the diffraction to some extent. Curt Campbell is an excellent speaker designer so I'd trust what he has come up with.
Going to a 1" roundover isn't going to hurt and might help. Going to a 1-1/2 inch or 2-inch roundover, you just don't know.
Going to a 1" roundover isn't going to hurt and might help. Going to a 1-1/2 inch or 2-inch roundover, you just don't know.
Because I'm not from the US and quite frankly the cost of these alone would most likely be similar to me having the entire thing machined 😉
Yeah... That's more or less what I'm worried about. I just wish Curt and Jim would still be active here, I'd love to ask them this question 🙁
I also have some random thoughts that came to my mind if someone could answer them:
- I'm going with WEE Tech WME MKP capacitors so they should be good enough, but I still am thinking if it wouldn't be better to make an external crossover instead of an internal one. I was thinking of splitting the crossover boards into one or two - one for mids and tweeter, one for woofers. I could position them at the back of the speakers in plywood enclosures so that the area they would take inside the enclosure can actually be covered with deadening material like acoustilux etc. Would that make sense?
- I'm also thinking of using either a bi-wire or a normal terminal. I know bi-wiring is not useful, but rather I don't want to lock myself out of possibility of bi-amping at some point. I was also thinking that it could be possible to wire them to a single terminal and then use the jumper to power a subwoofer by utilizing a high-level speaker input on the subwoofer (if it proves necessary) by essentially having a full speaker output from the second binding post pair. Does it make sense?
- Lastly, does the front baffle thickness matter? I originally thought about making it 12mm plywood to save costs but I found out I'd be actually wasting money - I will have leftover 18mm plywood that would be enough to make front baffles. Should I make them thicker? Should I alter the inner baffles to account for the changes?
@Vedemin - Curt is not active on any forum that I am aware of. Jim Holtz is on the Midwest Audio Club forum. Although he may say that Curt would be the one to know the impact.
Yes, both an external xo as well as splitting them in two makes sense and is somewhat common. You could incorporate them into a base if you want, but it would add a few inches to the height.
Yes, this makes sense too. Not sure if you can get something like this locally, but check out these TRIPLE binding posts.
I'm not sure about this.
Yes, most of the cabinet vibrations come from the woofers on the front baffle. 24mm to 36mm baffles are better, if you can make it work. Just have thicker front baffles and leave all of the internal dimensions unchanged. And make sure to remove some material (usually chamfer) the insides of the baffle round the woofers and midranges.
I think I'll contact them through their website then and try to write to Jim on the Midwest Audio Club.
I was thinking of placing them behind the woofers on the back of the speakers - no changes to placement but still removes them from inside the case. And if anything ever breaks, they will be easier to replace.
This might be fun but I think I'll stick with 2 posts since I have access to that. And I'm very unlikely to do bi-amping ever in my life so... But I will likely still attach both crossovers on a single binding post and maybe leave the bottom one just for the subwoofer? Dunno, will have to see if there are any meaningful resistances on the joint (I am certain they will be near zero).
As for the subwoofer, there are ones that take speaker-level input. So I could either splice the speaker cables and send them to both subwoofers and speakers, I could treat subwoofers as B set of speakers (lowering the amplifier power, I only have 80-100W, it's a Luxman L85V) or just make a set of wires from the speakers to the subwoofers. Should work pretty well, these subs like SVS are active and only take the speaker-level input to know what they're supposed to play, the amp won't power them.
From what I understand, the baffles there are 2 baffles - inner and outer. If they are glued with sound-absorbing glue, will it still matter that much? I don't think I'm willing to go much further than that 18mm since the cost spikes quite rapidly. I could technically go higher and do more funny roundovers though... tempting 😉
I will have to contact Curt or Jim and see what they think about such roundovers. I am very tempted to do them as they look very pretty and could technically provide some improvement in sound.
