I'd be inclined to doubt that the effect is audible with music signals in this case, at least above 2kHz. I just found it very strange that foam would increase odd-order distortion in this way. I do wonder if a Geddes-style foam plug filling the whole waveguide would have a significantly greater effect, but I don't have nearly enough foam to test it.
Interesting; thanks. The Dutch & Dutch 8c has rather high 3rd harmonic toward the bottom end of the midwoofer's range. Perhaps this is part of the reason?
What filament would you recommend to print the model on the left? Soft TPU? 😎
Could you please show some more photos of the assembled waveguide? It doesn't matter if botched, the more interesting it is 🙂
Overall, is there anything to be improved on the kit, from your fresh experience?
I still have plenty of foam, I'll try to do a test. Maybe the higher-order harmonics are even better masked by the increased low-order one, thus improving the subjective assesment - couldn't this be the effect of the foam in the end? 🙂 (Just kidding, I have no idea what's going on.)
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So, I couldn't resist giving it a go. This was printed on a Bambu A1 mini - £169. I wanted to try various metallic filaments. Since I last had a 3d printer - some 6 years ago or something, this machine is a different experience completely. The print quality is astonishing. And I've had ZERO print failures so far. It has a 180mm cube print area so I had to slice the throat horizontally - no problem though.
So, the good - well its so almost possible to get a final finish right off the machine. I've not tried epoxy or any other coatings yet.
The bad - I ended up with a 3mm gap on the last leaf. And I'm not really sure of the best way to fill it. My fault - I think that I could do it better the next time. The trouble is, as amazingly accurate that these prints are, there is no room for error at all. There are some strategies that can eat up errors that I use when making wooden horns - but this would mean some design changes.
Idea. How about sectional print with some compliant 'gasket' sections built in? Then some squeezing during assembly could tighten things right up. There might even be an aesthetically pleasing way to do it. I've not tried the TPU filaments yet. I'll get some and experiment.
So, the good - well its so almost possible to get a final finish right off the machine. I've not tried epoxy or any other coatings yet.
The bad - I ended up with a 3mm gap on the last leaf. And I'm not really sure of the best way to fill it. My fault - I think that I could do it better the next time. The trouble is, as amazingly accurate that these prints are, there is no room for error at all. There are some strategies that can eat up errors that I use when making wooden horns - but this would mean some design changes.
Idea. How about sectional print with some compliant 'gasket' sections built in? Then some squeezing during assembly could tighten things right up. There might even be an aesthetically pleasing way to do it. I've not tried the TPU filaments yet. I'll get some and experiment.
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Matab - I will take a few pictures tomorrow and upload and share my thoughts on assembly experience.
@maravedis - So what's your explanation of the gap?
@heijnsva - That seems just perfect. If all goes this well, you're lucky 🙂
- I'm still thinking about some real locks that would allow to "click" the parts together, to be able to try a complete dry run first. I'm only not sure I can actually design it that well. And it could have its own problems. One just can't assume a very good accuracy with these hobby 3D printers. Even if the prints seem nice.
I'm keen to improve it. Could you post a sketch?
@heijnsva - That seems just perfect. If all goes this well, you're lucky 🙂
- I'm still thinking about some real locks that would allow to "click" the parts together, to be able to try a complete dry run first. I'm only not sure I can actually design it that well. And it could have its own problems. One just can't assume a very good accuracy with these hobby 3D printers. Even if the prints seem nice.
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On textured PEI gaps due to warping 3-4mm are common from open enclosure and PLA. I'd like to see non filled filament that can do better.
@maravedis - So what's your explanation of the gap?
I did a dry run with tape (carpet tape from lidl is the best) which worked vary well. The small inaccuracies then distribute themselves. I got over eager with CA glue and until I was left with a final piece that I couldn't sand to fit. I'm sure it could be done better.
Next time I would split it up into 2 halves, which can be flattened at the join on a large piece of sandpaper.
But, even if it all goes well the joins look like joins (and there are very small gaps everywhere if you don't use foaming glue) And, there is still a risk of ruining many days of print - and you dont know this until the very final glue moment.
Of course, none if this is a problem if one is going to fill and paint.
I did a dry run with tape (carpet tape from lidl is the best) which worked vary well. The small inaccuracies then distribute themselves. I got over eager with CA glue and until I was left with a final piece that I couldn't sand to fit. I'm sure it could be done better.
Next time I would split it up into 2 halves, which can be flattened at the join on a large piece of sandpaper.
But, even if it all goes well the joins look like joins (and there are very small gaps everywhere if you don't use foaming glue) And, there is still a risk of ruining many days of print - and you dont know this until the very final glue moment.
Of course, none if this is a problem if one is going to fill and paint.
The joins will always look like joins as long as the printer nozzles are round, I'm afraid.
It would take quite a big printer to circumvent this.
Maybe the CA glue is not the best approach here, as it indeed leaves no room for even smallest later corrections. The Gen2 kits with the mounting jig seem better in this regard, after all (when used with a slow glue). Hmmm, perhaps I should reconsider returning to that 🤔
Anyway, tomorrow I'm going to assemble my A460. Will let you know how it went.
It would take quite a big printer to circumvent this.
Beware, this can be even worse if the parts are warped or twisted, so the errors accumulate in a way there's nothing you can do. Been there.
Maybe the CA glue is not the best approach here, as it indeed leaves no room for even smallest later corrections. The Gen2 kits with the mounting jig seem better in this regard, after all (when used with a slow glue). Hmmm, perhaps I should reconsider returning to that 🤔
Anyway, tomorrow I'm going to assemble my A460. Will let you know how it went.
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An idea occured to me - Is there anyone who tried to use bass guitar cabs to be used together with a big free-standing horn?
I mean something like this: https://www.thomann.co.uk/4x10_bass_cabinets.html
It would save some work 🙂
I mean something like this: https://www.thomann.co.uk/4x10_bass_cabinets.html
It would save some work 🙂
You mean when playing your guitar through your hifi speakers? Does it have more bass that way? 🙂
- I think there can't be anything right or wrong about it, it's just a part of the instrument, you either like it or not.
I would EQ it first, of course, for reproduction. 🙂
- I think there can't be anything right or wrong about it, it's just a part of the instrument, you either like it or not.
I would EQ it first, of course, for reproduction. 🙂
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It's just nature of how bass quitar tone is, it's very rich in harmonics and fundamental is usually lower in amplitude than the harmonics. In general, while recording and mixing bass I've found it hard to adjust with EQ as it really doesn't work almost at all as it changes harmonics of every note making it sound bit weird. Also, directivity is much better, typically bass speaker, like quitar speakers, beam a lot while the player itself could be 90deg off-axis and so on 😀 And this all combined to what I think sounds "natural" I think.
Plug bass quitar to hifi system and voila, best sound you've ever heard, the one you've been searching for swapping amps and speakers years on end 😀 I suppose there are many camps on bass tones, certain genres need some particular tone and so on, perhaps certain speakers are needed in recording to get particular sound from mic etc. anyway, just something to consider. If you intend to use bass speaker for hifi, make sure it's not bass speaker but hifi speaker 😀 Well, perhaps I'm mistaken and tried only bad speakers.
Plug bass quitar to hifi system and voila, best sound you've ever heard, the one you've been searching for swapping amps and speakers years on end 😀 I suppose there are many camps on bass tones, certain genres need some particular tone and so on, perhaps certain speakers are needed in recording to get particular sound from mic etc. anyway, just something to consider. If you intend to use bass speaker for hifi, make sure it's not bass speaker but hifi speaker 😀 Well, perhaps I'm mistaken and tried only bad speakers.
I wouldn't use the built-in horn, I have my own 🙂
And the directivity given by the 15" or even 4x10" transducers should be just what I want... Remember, this would be used only to ~800 Hz at maximum, with a proper crossover. Of course the transducers in the cheaper cabs won't be anything special, could be just junk in the cheapest cabs. That's to be avoided of course. But maybe they are all junk, I don't know, that's why I ask 🙂
So the question is - are they reasonably equalizable? Any experience?
And the directivity given by the 15" or even 4x10" transducers should be just what I want... Remember, this would be used only to ~800 Hz at maximum, with a proper crossover. Of course the transducers in the cheaper cabs won't be anything special, could be just junk in the cheapest cabs. That's to be avoided of course. But maybe they are all junk, I don't know, that's why I ask 🙂
So the question is - are they reasonably equalizable? Any experience?
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