I found a post by GM - from way back:
Seems reasonable, JBL obviously couldn't build anything that infringed on Altec's patent, but from just looking at the 2360's published data it may be a better sounding horn in a typical HIFI app, though a mouth foam surround smooths the mantaray right out.
And while I have searched high and low - I did not find any details on this approach.
I have to admit that I'm not at all unhappy with how the MR94's perform with 288-8k (metal horns with thick rubber structural damping on the backside)
I of course added some minor notch filters in the DSP. While the top roll-off is not insignificant, it is still manageable.
Would be thankful if anybody could share some details on this or hint me in the right direction.
There is an itch to try out both the 2360's and especially the 5671, which I have heard on one occasion as part of the 5674 system.
Still a bit worried that it might not work given the distance needed for things to come together. 29x29ft room though.
Seems reasonable, JBL obviously couldn't build anything that infringed on Altec's patent, but from just looking at the 2360's published data it may be a better sounding horn in a typical HIFI app, though a mouth foam surround smooths the mantaray right out.
And while I have searched high and low - I did not find any details on this approach.
I have to admit that I'm not at all unhappy with how the MR94's perform with 288-8k (metal horns with thick rubber structural damping on the backside)
I of course added some minor notch filters in the DSP. While the top roll-off is not insignificant, it is still manageable.
Would be thankful if anybody could share some details on this or hint me in the right direction.
There is an itch to try out both the 2360's and especially the 5671, which I have heard on one occasion as part of the 5674 system.
Still a bit worried that it might not work given the distance needed for things to come together. 29x29ft room though.
Have you ever seen a Urei/604 with a blue foam ring around the HF horn's? All truncated horns, i.e. virtually all horns require this to damp the terminus/mouth's eigenmodes from reflecting back to the throat, modulating/comb filtering with the diaphragm's output. You need an open cell foam such as trail pad/camper's mattress for large horns and per Dr. Geddes, 300 ppi (fish tank filter) if using a foam insert to do the same. To experiment, forum member Pano used a plush? bath towel wrapped around the terminus/mouth of his big multicells IIRC.
I did not come across the (very blue)Urei/604 until now.
It makes perfect sense - and I do see a somewhat undulating response that would match well with modulation and comb filtering.
Most of the foam I have at hand is closed cell - 30 ppi indeed seems to be common for aquarium and fish tanks, but I also have some speaker damping foam looking very similar in density.
Thanks a lot - also for the picture- this was very helpful.
It makes perfect sense - and I do see a somewhat undulating response that would match well with modulation and comb filtering.
Most of the foam I have at hand is closed cell - 30 ppi indeed seems to be common for aquarium and fish tanks, but I also have some speaker damping foam looking very similar in density.
Thanks a lot - also for the picture- this was very helpful.
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