any thoughs about the bamboo cutting plancha from IKEA : big model is big enough for a 2 way I think !
But magnitude spl shape (curve target) mainly rules over all the others parameters, no ? Ok, it is not saving bad drivers, bad filters and cut-offs choices, nore a bad load, bad enclosure layout, etc ! The way i see it is one can smooth an already good enough speaker by tamming the peaks where they arm, rigth ? 🤔
Response does not overpower other things. You will not build a good speaker unless you address the other things. Since response is easy to manipulate, the other things become all that matters.
I am not sure what your point is... ? I believe the KH150 uses FIR filters, what some call "linear phase", so it is possible to manipulate the phase response independent of SPL. Thus the designer was able to hold the phase more or less constant from 500 Hz up. A "normal" speaker with passive filters or IIR active filters will usually show a 360 degree phase shift from 500 Hz to 20k. So your point is that this is really impressive? or not, or ??
What is the bell ... ?
No, corner reflex duct sucks !
😀
I was referring to the bell shape in the graphic representation of some formula.
Now, you don't need my morning rambling ( as yesterday's...) but you might recall a certain persistency in the mulecules
to mantain motus, or stay still, whatever...
So every particle in our range of view ( scientific ) will show a rise, attack, decay ...something ( put a magnitude of velocity ...)
So a bell representing a molecule moving will show accelleration e deceleration.
If we de-compose velocity... nooo I'm lost !
A bell usually is associated to Q, just to be clear ! The concept of Quality is rather strange ...because Q is Quality, right ?
🤔
Edit, yes, quality as the abilty to select a narrow range, such in notch filters ( the HF argument is for me not useful)
The woofer solution with two PR and one of the most expensive woofers on the market is not cheap at all. If you can cope with a larger cabinet you would be better served by using multiple lesser woofers and making the cab sealed. What about a couple of these: https://audioxpress.com/article/test-bench-the-bwx-6501-midbass-from-misco-s-bold-north-audio-line https://store.miscospeakers.com/6-5-xbl-2-high-excursion-low-distortion-woofer-82109
It's not, its the total budget I have set. Woofers and PRs are only at $1300, MINIDSP unit is retail $500, if I were making this for market I'd have looked for a cheaper DSP implementation. And whats the point of any of this...FUN
To address other posts without getting repetitive, the budget still leaves $1100 for cabinet, amps, and tweeters, which isn't an unreasonable amount
I'm not going to buy more woofers, I'll be using what I have in-house.
I am at $1720, I don't understand the math here. My original budget to make something in the ballpark of the KH 150s was $2800, I figured a $700 savings would be worth the effort for something more aesthetically pleasing and similar sounding. Again, I already have the woofers and passive radiators, and I got them for a very, very cheap price. I'm just posting the MSRP because it isn't reasonable to think anyone else could get the Purifi stack for the price I paid.
I'm not arrogant to think I'm going to beat the Neumann engineers, but I think I can make something really nice leveraging DSP. I still have $1100 for the cabinets, amps, and tweeters, which isn't an impossible task, so mission not failed....yet.
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Thanks to everyone for sharing thoughts, advice, suggestions etc. all is very valuable and very appreciated!
Small update:
1. To address some of the budget comments, $2800 is the total budget I have set aside for the project. I thought a savings of $700 would make sense as making the project worth the effort vs just saving time and buying the KH 150s. Right now, MSRP of the project is $1720, leaving $1080 for the cabinet, tweeters, and amps, and that's because I'm counting buying a MINIDSP Flex into the budget, though if I was starting from scratch I wouldn't do that. The Purifi parts I do have I got at a ridiculously cheap price, so I'm stuck using them for now. Right now, the only tweeters on the table are the ones @augerpro has researched and designed waveguides for. Amps are going to be simple class D with enough juice to get the job done. Cabinet is where I might get some unplanned expenses.
2. I have a buddy with access to bamboo materials, hence the leaning to bamboo as a cabinet material. From what I can tell @planet10 is the resident expert in bamboo materials, so if I am understanding this correctly, vertical, carbonized bamboo is the minimum to be useful, and stranded is better just harder to cut cleanly? I shot an email to Plyboo about their products, I'm sure it's millions of miles better than the IKEA bamboo cutting boards I chopped up a few years ago
3. I attached a basic mock-up of the cabinet and baffles, I'm still going to try and make the baffles removable, thanks @hifijim for the great suggestions. The goal is to take a weekend to do some reading on Geddes and somasonus to figure out how I want to internally brace the cabinet. I also have a bunch of ideas how to mod the inside portions of the baffles such that they can be screwed into the sides of the cabinet from the driver holes, but screws have their own issues. Still, I don't want to drop the idea of the removable baffles unless I have no alternatives.
Current Status:
$1720/$2800 spent of budget
Augerpro tweeters only
Vertical carbonized bamboo cabinet
CLD bracing once I learn it from somasonus
Removable baffles with some kind of L brackets MAYBE
Small update:
1. To address some of the budget comments, $2800 is the total budget I have set aside for the project. I thought a savings of $700 would make sense as making the project worth the effort vs just saving time and buying the KH 150s. Right now, MSRP of the project is $1720, leaving $1080 for the cabinet, tweeters, and amps, and that's because I'm counting buying a MINIDSP Flex into the budget, though if I was starting from scratch I wouldn't do that. The Purifi parts I do have I got at a ridiculously cheap price, so I'm stuck using them for now. Right now, the only tweeters on the table are the ones @augerpro has researched and designed waveguides for. Amps are going to be simple class D with enough juice to get the job done. Cabinet is where I might get some unplanned expenses.
2. I have a buddy with access to bamboo materials, hence the leaning to bamboo as a cabinet material. From what I can tell @planet10 is the resident expert in bamboo materials, so if I am understanding this correctly, vertical, carbonized bamboo is the minimum to be useful, and stranded is better just harder to cut cleanly? I shot an email to Plyboo about their products, I'm sure it's millions of miles better than the IKEA bamboo cutting boards I chopped up a few years ago
3. I attached a basic mock-up of the cabinet and baffles, I'm still going to try and make the baffles removable, thanks @hifijim for the great suggestions. The goal is to take a weekend to do some reading on Geddes and somasonus to figure out how I want to internally brace the cabinet. I also have a bunch of ideas how to mod the inside portions of the baffles such that they can be screwed into the sides of the cabinet from the driver holes, but screws have their own issues. Still, I don't want to drop the idea of the removable baffles unless I have no alternatives.
Current Status:
$1720/$2800 spent of budget
Augerpro tweeters only
Vertical carbonized bamboo cabinet
CLD bracing once I learn it from somasonus
Removable baffles with some kind of L brackets MAYBE
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FYI I have a loaned Scanspeak 6640 on the way, and hope to measure it soon, so put that on your list. If someone is reading this, would be great to have SB/Satori's Be or TX tweeter to try making a waveguide for too.
Regarding the CLD braces, if you are in the US, Canada, or EU, use this for the constrained layer. Use normal wood glue to attach the braces to the box. Here is a pic of how was doing, but now I'm overlapping the braces more, about 90% of the distance:
People really seem to see CLD boxes as too hard to do, so I just built a 3/4" plywood box with CLD braces and Resonix applied. I'll post the results as soon as I get them. This would really be the minimum I would if I just wasn't interested in making CLD panels.
Regarding the CLD braces, if you are in the US, Canada, or EU, use this for the constrained layer. Use normal wood glue to attach the braces to the box. Here is a pic of how was doing, but now I'm overlapping the braces more, about 90% of the distance:
People really seem to see CLD boxes as too hard to do, so I just built a 3/4" plywood box with CLD braces and Resonix applied. I'll post the results as soon as I get them. This would really be the minimum I would if I just wasn't interested in making CLD panels.
Thanks for stopping by augerpro, you've done really great work and I've been slowly reading up on your website. I'm not rushing through this project so I'll be waiting for your posts on the Scanspeak, thanks for letting me know!
You're 100% right, without reading too much into the subject I've always chalked CLD as a complex topic that would take a long time to get a good handle on. For now, thanks to you, I'm hoping a 3/4" vertically stranded bamboo box with CLD braces (90% overlap with Weicon) and Resonix will be good enough to get the job done.
Do you think its worth looking at something other than MDF for the actual braces?
Thanks again, one post and already a massive help for this project!
You're 100% right, without reading too much into the subject I've always chalked CLD as a complex topic that would take a long time to get a good handle on. For now, thanks to you, I'm hoping a 3/4" vertically stranded bamboo box with CLD braces (90% overlap with Weicon) and Resonix will be good enough to get the job done.
Do you think its worth looking at something other than MDF for the actual braces?
Thanks again, one post and already a massive help for this project!
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Yep. I would look for a Shore A hardness of upper 30s to low 40s.