3D printed mark audio pluvia 7 build

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi guys,

I recently got a 3D printer, so I could learn more about CAD systems, and had some Pluvia 7 drivers I got off Mark at a recent hi-fi show, so it seemed rude not to have a play!

Based off the 9 litre vented design on the MA website, this first design is very much a proof of concept, I've started desigining the second iteration to have a lot more bracing as part of the actual 3d print, instead of being separate, and also having as many surfaces with complex curves as possible, to keep rigidity as high as possible.

The walls are 5mm thick in total, with 1.4mm each side of solid plastic and a core with 40% infill, I figure the combination of solid and slightly spongey will help dissipate energy better than a solid print, and be quicker and more efficient to print. The final speaker will get an internal coating of noise damping sludge and an external coating of epoxy resin that will be sanded and painted.

Anyway, onto the pics!

3D model
An externally hosted image should be here but it was not working when we last tested it.

My little printer and the first of 3 parts being printed
An externally hosted image should be here but it was not working when we last tested it.

Driver fits great!
An externally hosted image should be here but it was not working when we last tested it.

I ran low on black filament and my next roll is a slightly different shade and I had a bit of lifting on one side, but it fits and it's starting to come together!
An externally hosted image should be here but it was not working when we last tested it.

Part 3 is still being printed, but tomorrow I should have a fairly functional speaker!
 
Looking good!

You seem to already have thought of everything that I might have suggested for the 2nd version.

I've started desigining the second iteration to have a lot more bracing as part of the actual 3d print, instead of being separate, and also having as many surfaces with complex curves as possible, to keep rigidity as high as possible.

Sounds good. I'm yet to try this sort of thing, so this is a bit of a guess: are complex curves hard to model? A simple grid + angled side walls might be more achievable. If you do an image search on "plastic pallets" you might see some layouts / ideas you'll want to steal. I assume the people who design those have optimised them for a good material:strength ratio.

The final speaker will get an internal coating of noise damping sludge

Sweet. Should work well in a light cabinet.

I'm impressed by how little warping there is. The pieces appear to interlock nicely. What are the indentations for - are you thinking of running long bolts right through the cabinet as braces?
 
So, my life got turned upside down for a bit towards the end of this project.

So I scrapped it, as I decided I needed more bass in my life than 4" FR drivers could provide on their own.

My new concept is, full range driver in a small, sealed enclosure (2 reasons for sealed, I prefer the transient response, and with a slightly undersize enclosure, I can make them falloff at my XO point so I can simplify my xo's)
And a 5" to 6.5" vented woofer providing everything it can to fill in the bass, f3 of under 60hz and a cabinet 7 litres or less was my goal.
I wanted to create something that both had the soundstage advantages of full range drivers, but the extension, impact and ability to be driven really hard in a compact design, like a more traditional loudspeaker. Doing some quick maths, I came up with a maximum XO point of 250Hz, which is where I quickly realised why this idea has very rarely been put into practice commercially, air coil inductors that big are shitting expensive, luckily ESR isn't that big of a deal on a high pass, and you can get away with iron core for the lowpass as it's only playing the bottom 2 octaves, still, not gonna be a cheap XO by a LONG shot, luckily I can run fully active for testing.

I started auditioning the full range drivers I had to hand, markaudio pluvia 7, some of those tangband jobbies and some hybrid audio legatia L4, the TB's were an instant write off as I could only find one, and urghhh, are we really gonna pretend anything outdoes the L4's? The MarkAudio's did put in a good performance, but the top end and staging just weren't on the same level.

Here's a pic of them in hot contention.

dqtZ5lj.jpg


Then onto woofer considerations, for auditioning midranges I was just using the bass drivers still in their boxes from a £150 pair of active monitor speakers, as all of my stock I had laying around was 6.5" or more, which is larger than my 3d printer can accomodate, I had to go shopping. Was finalising between some peerless, sb audio and dayton units, when I saw some gorgeous bnib 5.25" Seas ER15rly units on Ebay that I snagged for £58, sorted.

Enclosure design was based purely on how few parts I'd have to print to get something good, with just under 200mm in each dimension, and wall thickness to consider, 6 litres per print was a reasonable goal. The top half is just empty space and driver mount, the bottom half is a completely printed in place port, plus a bit of extra space. For this design it's tuned to 44hz, with a vent cross area of 52mm x 26mm and nearly 400mm long including flares! Which is pretty crazy in a tiny monitor speaker.

Here's the render of my first mock up of the midbass enclosure, a few things have changed, a few things will change still

ve9SwyQ.jpg


here it is with a driver in situ, first changes are going to be making the rebate go all around the driver instead of falling away at the sides with the bezel, it just doesn't look "right" at the moment and re-doing the bracing, it's a bit ****. The print also went pretty **** as I was trying to use up a roll that I'm not keen on and I had a few issues.

qdfMDO1.jpg


And here's the bottom half currently being squeezed out, really happy with how this one's looking so far

RcK8saQ.jpg


At around 50 hours per speaker to print, even with an oversized nozzle, this is a patient process, but it's awesome that I can get a fully built enclosure, with bracing and fancy fluted port without a spec of sawdust or a single sawn off thumb end :D

I do plan to get some fibreglass and CSM on the inside though to stiffen them up and add weight
 
I'm just using PLA plastic, which is very easy to print, has almost zero shrinkage and costs about $15 a kilo for the cheap stuff, which works fine.

Then I suppose you'd have to factor in electricity costs, the printer uses about 200w in normal use (300w when the build plate is heating up)

The little midrange pods have 2mm thick solid walls, 10mm front plate and I can stand on them without them deforming at all thanks to their shape. They use a bit under 200g of plastic each and take 5- 6 hours to print witha 0.6mm nozzle on my printer.

The midbass box has 3mm walls and uses a bit over a kilo of plastic for each side! This is a long *** print, my printer will be going flat out for ~100 hours for all 4 parts.

I get electric bundled in with my rent, so for me this is all very cheap.
 
These are all just test boxes at the moment.

The idea is to print boxes for all and any drivers that I may want to put into a commercial design, so I can easily swap them around and see what works with what.

When the final boxes come, then I'll pay better attention to baffle shapes & sizes and what-not.

Thanks for your input though :)
 
Can't wait to see where this ends up. For the past few years I've been thinking about doing something similar but with a focus on absolutely reducing diffraction from the enclosure. I'm curious what nozzle size you are using, if I were to make an attempt at this I would definitely want to move to a .8mm or 1mm nozzle.

I also thought about designing a labyrinthine interior to the enclosures, as you could really build in some internal absorption and diffusion into the interior, without greatly increasing your build cost or time.

Keep up the great work
 
thanks man, i'm on a 0.6 nozzle, 0.8 was too much work to make look nice, i'd rather it had 40% more time printing! i started on 0.4, that was an error! Get on it though, it's so much less restrictive than designing for wood.

really fancy structurally strong interior is on my to do list, designing things so they print nice without supports is a bit of a challenge though.
 
Hello.

Do you think it's the rising up to the slightly hot 5-8khz region that makes you like the hybrid audio legatia L4?

Maybe this makes it better off axis, and gives more presence together with the room. There is something going on with cymbal hits, snare hits, tom's and even unfiltered kick up in this region. Also bringing out more subtle details that can often be missed. Loud horn sections can be a bit irritating though, and many studios put emphasis on voice and guitar over all else, making the recordings irritating even on speakers without a rising top end.
 
It's the whole presentation of the soundstage after a bit of careful positioning that I really love about the hybrids. I'm currently using these speakers as a pair of monitors for my desk, and 30 - 40 degrees off axis pointing infront of me and I feel like I'm front row at a concert.

Usually I'm the first to bin anything that sounds a bit too harsh or coloured, and whilst these can make your eardrums tingle a little if they're pointed at you, they are on the dark side of neutral, with a lot of "air", in their current position.

Due to their finicky nature I wouldn't really recommend them for anything other than monitors, where you can keep a very constant position.
 
Yes, that is what I meant, they interact "with" the room, in a way. Feels "live".
Same thing happening with my Fane FC152's, see that the drivers you chose have a somewhat similar frequency response. IE rising top end peaks at the 5-6-7-8khz then backing off a bit. It does not bother me like a hot region in the 700hz to 1-2-3-4khz area. Feels like detail level is enhanced or something, bringing back a little something that was lost.
 
Last edited:
It's the whole presentation of the soundstage after a bit of careful positioning that I really love about the hybrids. I'm currently using these speakers as a pair of monitors for my desk, and 30 - 40 degrees off axis pointing infront of me and I feel like I'm front row at a concert.

Usually I'm the first to bin anything that sounds a bit too harsh or coloured, and whilst these can make your eardrums tingle a little if they're pointed at you, they are on the dark side of neutral, with a lot of "air", in their current position.

I looked the driver up, out of interest.

That angle / those observations look just right, based on these 3rd party measurements:

Mobilesoundscience.com

- an on-axis rise and no huge peaks.
- very flat to about 9kHz when 30 degrees off axis.

IMO, this is a nice compromise, and looks to be well executed. I've tested (and enjoyed) some 4" TV and PA speakers that had similar polars.

I like that you say that is a lot of "air", when the measurements indicate there is almost no output > 10kHz at your listening angle. I see this as anecdotal evidence that the top octave is pretty unimportant, most of the time. Maybe the "air" comes from there being a little bit of >10kHz in the reflected sound.

Due to their finicky nature I wouldn't really recommend them for anything other than monitors, where you can keep a very constant position.

Aren't they meant for cars, where the position is very constant?

NOTE: the manufacturer specs are a little overblown - they use a sensitivity specification. The 3rd party measurement of the efficiency is 4dB lower. This puts it in the same range as the Visaton B80.

The B80 looks (just based on photos) very similar from the front - it may use some of the same parts, and it has similar polar plots.
 

Attachments

  • HATL4V103060Deg.png
    HATL4V103060Deg.png
    191.4 KB · Views: 280
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.