I’ve got a whole bunch of possible project ideas on the backburner. One planning to use veneer from the same sheet as this project, so I thought I’d hash this idea out a bit more to make sure I’ll have enough veneer left.
This was originally inspired by the girthy trunk of <.5% distortion the MAC05 has been measured at. I figure, double them up and have more chance at listening levels that maintain the low distortion.
(7th post down)
Next was trying to find a tweeter that didn’t break the bank.. While also matching that distortion performance, and capable of crossing just below the woofer’s distortion peak. I landed on the SB aluminum dome tweeters. The ceramic coated one happens to decently match the MAC cone color scheme.
(measurements of the non ceramic)
I’m still not great at determining lowest crossover for tweeters but, judging by the distortion performance, hoping I can eek out ~1.8khz. A resonance notch would probably determine the lowest possible crossing frequency anyway.
-1.8-2cf ported tower realy unleashes the LF capability of the drivers. It should handle at least 100db/1m down to just above F3. I’m typically happier when I don’t need to think of a sub. And for some reason I just like towers.
-1cf-.75cf sealed seems reasonable for use with a sub. Smaller size for when it is in storage, listening to other projects. More power handling. But It wouldn’t realy be the whole package to bring to gatherings unless I bring sub/s too.
I’m typically looking for a ballpark figure rather than exact. So I haven’t messed much with the Q stuff in the software. It doesn’t realy seem to have much effect. Dropping Qa down to 20 only drops the peak by ~.25db on ported. The series resistance makes a much bigger difference. I don’t think WinISD takes into account parallel or series driver wiring. I imagine additional series resistance would have a different effect on those configurations? Since the drivers are 4ohm I was expecting to put them in series. Would I halve the additional series coil dcr in order to maintain proportion within the software?
The incriments on the graph are .5db. So in the end the ported hump is still under 2db.
This should be a great build - and yeah, I wouldn’t sweat the 2db hump, at worst will warm things up a bit which is not always a bad thing, otherwise the room generally dominates there anyways.
Yeah, sorry guys. I know the gripe about “standardizing” graphs. I just like the .5db scale so I can actually notice trending differences as I make changes. Vs a tiny barely perceptible change in the wiggle.
Aluminum cones tend to be delicate.. and sometimes fingerprint magnets. So I might actually do a grill for when it is more than just us in the house. I’ve been kicking this idea around to have the grill board be part of a large radius. Grill removed, would be more like a baffle facet.
Would need to be integrated early on in the build. Grill board gets installed, then run the whole shebang down the router with a big 1.25-1.5" roundover (slowly taking bites out over many passes). I’ve got some metal grill peg guides. The plastic ones I figure would just shear off.
If I can get pumped up about it I might try to make some sort of sawdust tomorrow. Also have a Kolsch that needs bottled so no promises
Can’t wait to try out the veneer I have for it. It will probably be the nicest stuff I ever work with. A full sheet of quilted Makore. It was a bit of an ebay splurge last year.
This veneer is what I wanted to try a french polish with. I thought I might do a mini speaker with it to get more familiar with the technique, but I don’t want to inadvertently use too much of it, or cut too short that it won’t work for the larger project.
I rummaged around storage and found I still have plenty of the black laminate left. Thinking of doing black front/back + top/bottom. Then veneer the sides, wrapping around the partial roundover. I’m thinking that would create a ton of contrast, making the driver color realy pop, and create just enough visual complexity without being gaudy. Also, the black rubber grill cups should blend into the black baffle enough to not distract from the overall form. With the grills on, the light driver color peeking through would be pretty cool to IMO.
