I don't understand why the aluminum isn't applied on the baffle ( beside it).
It's the place where the major forces apply to the surface ( the basket's vibrations) and where you would want neutrality. Minimum 1 cm sheet would be needed and, TBH, I haven't done it yet
I could have done the aluminium sandwich thing for the front baffle, but I didn't for practical reasons. The shop didn't want to do circular holes for the drivers.I don't understand why the aluminum isn't applied on the baffle ( beside it).
It's the place where the major forces apply to the surface ( the basket's vibrations) and where you would want neutrality. Minimum 1 cm sheet would be needed and, TBH, I haven't done it yet
Most of the front baffle surface is consumed by the drivers anyway, very little would be left for the aluminium sandwich. The woofer is suspended by the two side walls and the bottom. The little piece of front baffle next to the tweeter and midrange is supported by the internal bracing. Overall, the small part of the front baffle that is not covered by the drivers is very "dead" in the knock test.
Mmmhh, it doesn't stand: a knock test isn't the same as a woofer working.
Moreover, you attached to the same structure either the midrange and the tweeter. Those are subject to a continous knock test during functioning.
Probably it's better to leave only the wood for suppressing the vibrations
Moreover, you attached to the same structure either the midrange and the tweeter. Those are subject to a continous knock test during functioning.
Probably it's better to leave only the wood for suppressing the vibrations
I have asked myself exactly this question this morning
I intend to make a list of the drivers and the xover parts with the involved costs sometime soon. The costs of the cabinet depend a lot on the materials you're going to use, and if you make them yourself or have them made professionally by someone else.I like to keep the x-overs outside the cabinet. In this particular design the x-overs are rather large, and they would take up quite a bit of space within the box. Also, keeping the x-over parts away from the mechanical vibrations in the box is usually a good idea.
Thanks! I have to admit that I had some help from a carpenter (I don't have the machines to cut large sheets).
The measurements are scattered all over this thread, you just have to find them
I added some pointers to the first post of this thread (scroll down), but I am sure there is more.I am still in the process of compiling and sorting out all the data. Some of this is already in the documentation PDF, but there is more to come: osmcdoc/osmc_paper.pdf at master * mbrennwa/osmcdoc * GitHub
I just looked it up: drivers would be 870 Euro for each speaker. Add x-over, waveguide, cabinet, and bits and pieces and you end up at approximately 1500 Euro. That's a lot of money, but you get what you pay for (and more).
I finished the second box!
I am sill waiting for the last bits and pieces to complete the final build of the xovers. In the meantime, I have worked a bit on the documentation. I guess this still needs some polishing here and there, but most things are there. Would anyone like to have this published in a proper journal? audioXpress is gone, and so is Linear Audio. Thoughts?
GitHub - mbrennwa/osmcdoc: Documentation for the Open Source Monkey Coffin
I am sill waiting for the last bits and pieces to complete the final build of the xovers. In the meantime, I have worked a bit on the documentation. I guess this still needs some polishing here and there, but most things are there. Would anyone like to have this published in a proper journal? audioXpress is gone, and so is Linear Audio. Thoughts?
GitHub - mbrennwa/osmcdoc: Documentation for the Open Source Monkey Coffin
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Looking at power response i was wondering - aren't you just a little bit worried about that hump from 700Hz-1300Hz ? Have you tried to linearize it and have a listen for subjective differences ? The coloration might not be insulting to he ear but given it is a power response graph, it is there.
It might be just my ocd speaking but it itches me when i look at it - more so because rest of it is done with more attention than what i've used to see (taking the restraints of the design target into consideration).
It might be just my ocd speaking but it itches me when i look at it - more so because rest of it is done with more attention than what i've used to see (taking the restraints of the design target into consideration).
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I know what you mean, I thought the same. I did try to reduce the SPL a bit in the 1 kHz range. My ears preferred it the way it is. I guess it all boils down to how we perceive the sound, and how this relates to the measurements and diagrams. Sometimes speakers sound better if we don't completely remove the acoustic imperfections from the measurement results.
No. It's typical wider radiation sector of small driver with (too) steep XO slopes. It is partially compensated with small attenuation in axial response - just how it should be if other methods are not used or possible.