Mechano23 Open-source DIY Speaker Review

[EXIF68]

This speakers have some similarities to my DXT-MON. same concept, small woofer with wave guided tweeter. only difference: simpler cabinet and lack of passive radiator.

 

[MacClintock]

Amazing.

 

[dogmamann]

Would spot bracing fix the resonances ?

 

[TheBatsEar]

bass would become "papery"

The other day my cat became papery.

Looking at this price and performance, speaker manufacturers are starting to have some explaining to do.

Imagine someone selling a complete kit for 500€ after fixing the resonances.

 

[Count Arthur]

View attachment 366452
The other day my cat became papery.


Imagine someone selling a complete kit for 500€ after fixing the resonances.

You seem to have a chicken on the loose too.

 

[TheBatsEar]

You seem to have a chicken on the loose too.

How do you explain a loose chicken and a papery cat in one day?

 

[alekksander]

this is gold!

 

[kimmosto]

"Open source" is for softwares. This is free diy loudspeaker kit so it should be "free design".

 

[somebodyelse]

Would spot bracing fix the resonances ?

I don't think so. The one around 1kHz looks like a pipe resonance in the reflex port. There are techniques to reduce this if you think it's a problem. Over 10kHz it's probably something in the tweeter or waveguide.

 

[holdingpants01]

I don't think so. The one around 1kHz looks like a pipe resonance in the reflex port. There are techniques to reduce this if you think it's a problem. Over 10kHz it's probably something in the tweeter or waveguide.

the horn is part of the tweeter and there's no resonance in the data sheet https://www.scan-speak.dk/datasheet/pdf/h2606-920000.pdf

 

[BenB]

The waveguide on the tweeter makes all the difference. I thought a waveguide would be difficult to implement, but not any more. Low cost too. I should throw away all my flat baffle tweeters. They are all obsolete.

I feel the exact opposite. That's why it's nice to have options. This is a great option for people who don't demand the widest dispersion. The measurements are really impressive. I understand it's supposed to be a cheap speakers, but as a DIYer, I have never put Electrolytic caps in any of my designs, no matter how inexpensive they were supposed to be. I'd think something this good deserves decades of reliable service. I'd upgrade the caps, personally.

 

[jaakkopetteri]

Would love to see some chamfers around the tweeter/wg and maybe a bit of playing with the port geometry to reduce the resonance - seems like a fairly free lunch, but then again probably not a significant improvement. Can't think of much else than getting a more expensive woofer as SB aren't that great in IMD, but that would also matter mostly for louder listening

 

[D!sco]

Congrats on another successful DIY design reviewed. I bet an MTM would be even better given the distortion profile.

 

[Salt]

This is a very good example for constructing a speaker. Very good.
And it is a perfect example that DIY is not only for fun (as many times rumored here) but can save a lot of money and in parallel can give a more satisfactory over all result by detecting the fitting driver for the proposed frequency range and cabinet, regarding distorsions, dispersion, T/S-parameters and so on, and x-over them properly. Without some theoretical and practical skills a Kit like this would do, of course.
Why DIY saves money?
Last time I had deep insight into calculations of audio devices it was for speakers the double-for-every-step:
producer sells for double of costs to distributor (400->800), distributor sells to reseller (800->1600), reseller finds a person that pays 3200 for it.
So this would have been the price range to compare to a commercially available speaker.
This calculation is one of the reasons why I had the last commercial speaker more than 30 years ago and all that measuring and woodworking tools amortized soon.
(and btw don't like lytic caps either except > 100 µF)

 

[Randolf]

Baltic birch cabinet seems quite solid and well above what you get commercially. I was surprised to see a tweeter with waveguide. Typical DIY speakers lack that

Very nice review of a nice affordable DIY example. To me the ability to choose between all different kinds of drivers (Dome, AMT, Ribbon, compression, waveguide, ...) and cabinet types (sealed, bassrefelx, Transmission Line, TQWT, Horn, ...) is one of the biggest advantages of DIY. Here are some examples of other affordable DIYs using Wavecor waveguide dome tweeters:

https://www.lautsprechershop.de/hifi/cursa_en.htm Wavecor TW030WA12
https://www.lautsprechershop.de/hifi/powercor_light_en.htm Wavecor TW030WA11
https://www.lautsprechershop.de/hifi/cordial.htm Wavecor TW030WA11
https://www.lautsprechershop.de/hifi/wavemon_146_en.htm TW022WA05
https://www.lautsprechershop.de/hifi/wavemon152_22.htm Wavecor TW022WA06

Since the Mechano23 comes with a VituixCAD 2 project I found it very interesting to compare the VituixCAD 2 predictions with the actual klippel measurement results, some VituixCAD predictions:

VituixCAD prediction looks pretty good to me and it makes the DIY task a lot easier.

 

[jhaider]

This leaves me shocked. What excuse do large companies have for not designing and selling such a well-made speaker if a single user with limited means, with easily available materials and knowledge available to everyone can design such a well-measured speaker?

Look at the crossover - it's complicated, with a fair number of big and expensive parts. Here's a pic from the build thread.

This is the kind of thing that's "easy" for an advanced DIYer to do in small quantities, but adds up quickly in materials and labor costs for a commercial product. It's certainly doable, but probably not at the outlay one would expect for a 5" 2-way.

Regardless, really really nice mini-monitor design that's a great showcase for SOTA in passive designs using well-chosen drive units of reasonable cost.

 

[MEGB1262]

Hi all,

i have started a lot of years ago with this here

and now this...

i have played around with the Visaton BoxSim 2.0 simulation program, VituixCAD has a far different learning curve, i think it takes years of experience to get out something like this construction of it

I don't think the developer has been just lucky, he knows very well what he is doing

The complexity of the crossover is the key to the success using quite cheap drive units to workaround their weaknesses

Exactly the opposite of what KEF is doing - cheap cabinets and very simple crossovers with the mass market Q series and the Uni-Q drive units that can perform 2 classes higher with a decent crossover like in the Reference Series where of course the driver units gets some additional fine tuning with neodym instead of ferrite magnets and some more tweaks as you can read in their R & D papers

So far - so good, Stefano

P.S.: i think a 1.8 uF cap + this here https://www.reichelt.de/it/en/mkp10...30-vdc-rm-22-5-mkp10-630-220n-p31980.html?r=1 will do the same

 

[Barnaby1]

Look at the crossover - it's complicated, with a fair number of big and expensive parts. Here's a pic from the build thread.

This is the kind of thing that's "easy" for an advanced DIYer to do in small quantities, but adds up quickly in materials and labor costs for a commercial product. It's certainly doable, but probably not at the outlay one would expect for a 5" 2-way.

Regardless, really really nice mini-monitor design that's a great showcase for SOTA in passive designs using well-chosen drive units of reasonable cost.

I agree with your general sentiment but I'd quibble with describing the crossover as big and expensive. The crossover list and prices is in the first post of this thread. Each crossover has 13 parts and costs $49 based on the design shown above. I built the Jeff Bagby Tributes and they have one of the more simple crossover designs I've ever seen. Using the cheapest parts, it was $52 and 5 items per crossover. I'd hardly call anything about this speaker expensive. Now Troels designs...those are big and expensive.

 

[Salt]

Look at the crossover - it's complicated, with a fair number of big and expensive parts. Here's a pic from the build thread.

This is the kind of thing that's "easy" for an advanced DIYer to do in small quantities, but adds up quickly in materials and labor costs for a commercial product. It's certainly doable, but probably not at the outlay one would expect for a 5" 2-way.

Regardless, really really nice mini-monitor design that's a great showcase for SOTA in passive designs using well-chosen drive units of reasonable cost.

Don't see any unreasonably expensive materials in this, but considering the n^2 for sale's price it might matter ... not for sound quality, but pricing.
There are 'fatter' examples of X-over materials, even by my own

 

[kelesh]

I was trying to locate a US source for the parts and, interestingly, the mid/bass driver "SB Acoustics sb13pfcr25-4" as listed in the project shows up as a different type of speaker on Madisound in the US - www.madisoundspeakerstore.com/sb-acoustics-sb13pfcr25-4-coax-5-paper-cone-coaxial-4-ohm-round/. This one has the same part number as the one on Solen, but is a coaxial driver with a center mounted tweeter, similar to Tannoy dual concentrics. Opportunity for a different version of the design?