Just don't ask help from Boeing engineers...
Seriously, front panel frame structure is also a good source for extra diffractions. It must be made and tested carefully
I am not a fan of threaded rode as they form a resonator. But if taken care of that, why not.
What is important on a joint is to mount it "wet", iow no air between the flanges. In the past mounting vibration sensors on rotating equipment was in the form of an M16 bolt.
Mounting dry or wet(little bit of grease) made quite a difference. Same with record players (way past ;-)) , it made a difference.
Well that rules out my help
... I was 30 years at Boeing on military aircraft... Aircraft are one of those products where engineering and manufacturing can do a million things right, and one thing wrong... and the only thing that matters is the one thing we got wrong...
Well that rules out my help
Aircraft are one of those products where engineering and manufacturing can do a million things right, and one thing wrong... and the only thing that matters is the one thing we got wrong...
My "Boeing story:"
Nearly a decade ago, I built a cluster of computers for them. I did the implementation, the configuration, the whole nine yards. It was just me (a contractor) and another dude at Boeing. We set up the entire thing.
About a year later, a recruiter from Boeing contacted me. They were looking to hire someone. They had a list of requirements which was clearly sourced from someone in management who wasn't familiar with the project.
From the job description, it was obvious that they were hiring someone to maintain the cluster THAT I BUILT FOR THEM.
Told the interviewer in human resources that I literally built the cluster that they were looking to find someone to maintain. On the entire planet, there was nobody who knew it better than me.
The recruiter seemed to have rocks in their head, and as I described this, they continued rattling off a series of "nice to haves" for the position. For instance, the hiring manager wanted someone who "knew Java." I'm not a Java programmer, and there's literally zero lines of code in that project that were written in Java. Most of it was Python; I know Python well.
Eight weeks later, one of my coworkers quit. Boeing had hired him. He'd never worked on the project at all.
Moral of this story: if you're looking for a job in tech, and you fail the interview, don't feel bad. The people in human resources have rocks in their head.
If made passive at the end, the choice of the filter passive parts quality migth be a part of the quality the drivers deserve, imho. Look forward to see the devlopment with the good fluid skills. In a dev I made but didn't finished yet due to time problems, one of the trade off choice was a double layer front baffle. The inside one being structuraly a box panel with its internal couplings. the top front panel side had to be on a flex glue à la Syca FC11 or equivalent. the drivers being screwed on this front panel only, story to damp more the cabinet vibrations. Certainly a detail VS a sota filter and WG design and integration with the midwoofer.
I also wonder about how the spead of the 34A will sounds VS a said "better" 25B narower directivity in a WG as well...
I also wonder about how the spead of the 34A will sounds VS a said "better" 25B narower directivity in a WG as well...
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Maybe, I am not generally pre disposed to pick passive but I am not against them either. If I want anyone else to build one then I would have to design a passive crossover. I don't have a store of passive parts to play cut and try with either. I like to use quality parts but I am well past the point of ascribing magical sound quality to specific parts, I will leave that to others.
Me too, one day I might be able to tell you what I think, I have a pair of T-25B's as well.
Sorry I can't because I haven't, Vituix will be getting real data this time
Do you have a pair of the Aluminium 6.5 Purifi drivers? For now I can print reliably in ABS. There is a nice looking riser on Printables that smooths out the filament path and relocates the filament sensor. The stock position creates a horrible path for the filament to have to go through and is no doubt part of the unreliability of CF filaments.
I have a similar feeling, much easier to avoid ground loops too. The Purifi application note shows how a passive notch can be used as part of a crossover without too many parts. The T34A on the waveguide should also be relatively easy to passively filter but that remains to be seen.
How do you intend to optimize the geometry then?Sorry I can't because I haven't, Vituix will be getting real data this time
Yeah I have the 4ohm alu 6.5 drivers, and the paper 4 ohm too. My current speakers use sealed papers with a waveguided sb26adc, crossing to subs. I been waiting for the purifi tweeter to build something ported 2 way with the alu 6.5's, but happy to play around with the T34A's I've had for years instead.
I have read the purifi app notes and have already played around with those notch filters on the alu woofer in test boxes.
I have read the purifi app notes and have already played around with those notch filters on the alu woofer in test boxes.
The geometry is optimized for the waveguide, with wide directivity designs the box shape has more influence on the best waveguide profile. For the woofer the aim is to keep the directivity from the box as low as possible. The simpllest way to do that is to round the corners as much as possible. The box is shallower than it is wide so the box shape will not cause any problems to the goal.
I simulate to find the answers to things I don't know, not to confirm what I already know.
Sealed passive would work for that situation, but for lots of use cases the drivers end up needing to be ported or use passive radiators to get the bass level up. I am not inclined to make a vented speaker for my own use which is why I was leaning towards sealed and active. Of course EQ could be used in a sealed passive speaker but that makes it a bit awkward. I did buy some ports to try a damped vent similar to what Troels did with one of his Purifi designs. I might need to make my first test box flexible so I can try a few options out.