Mechano23 Open-source DIY Speaker Review

[Barnaby1]

Its important to distinguish between particle board and MDF. There are significant differences.

I would never make a speaker out of the former, while the majority of both DIY and commercial speaker enclosures are made from the latter. The linked cabinet is described as MDF, fwiw.

Just to clarify, in case someone was planning on ordering. It is a mix of both.

• 3/4" MDF Front and Back for easy Machine Cutting.
• PB Top and Sides

 

[Salt]

See it different.
MDF is mostly and mainly used for reason of easy use (sharp edges, easy milling etc.), but on the other hand sound transmission can be despersed and thus damped with irregular structures like particleboard or OSB.

 

[somebodyelse]

Is particle board a good material for speakers? I haven't seen many DIY ones built out of that.

It was used a lot before MDF took over. Probably still is at the bottom of the market.

Shelves aren't speakers.

Indeed. It's a lot better suited to speakers than shelves!

 

[Great Sun Jester]

It was used a lot before MDF took over. Probably still is at the bottom of the market.

Indeed. It's a lot better suited to speakers than shelves!

I've spent the last 40 years of my life woodworking and really don't require any tips, but thanks!

 

[Jon AA]

Very nice job, XMechanik!

 

[pseudoid]

Its important to distinguish between particle board and MDF. There are significant differences.

idem: Thickness.

 

[Salt]

idem: Thickness.

That's one (the old fashioned) face of the coin, the other is proper bracket placing; combining both never hurts (except the back), and additional damping on the walls inside can't do no harm at all.

 

[Rick Sykora]

View attachment 367192
Alternative crossover by @kimmosto . Dashed lines original XO

Cool, gets the part count more reasonable at least.

 

[Salt]

View attachment 367192
Alternative crossover by @kimmosto . Dashed lines original XO

Is this a physical/measured configuration and not only simulation (Tekton-Style) ....?

 

[jaakkopetteri]

Is this a physical/measured configuration and not only simulation (Tekton-Style) ....?

Both XMechanik's measurements seem to agree very well with Amir's spin, so I wouldn't worry about that

 

[Rick Sykora]

Is this a physical/measured configuration and not only simulation (Tekton-Style) ....?

Just to be clear, it is both. It is a VituixCAD sim based on the driver measurements supplied by the designer. Yes, the sim does match pretty well (above 1 kHz) to the Amir’s more full measurements.

 

[Inertiaman]

Just to be clear, it is both. It is a VituixCAD sim based on the driver measurements supplied by the designer. Yes, the sim does match pretty well to the Amir’s more full measurements.

So to dumb this down (for me, perhaps others, too): one could substitute this crossover and be confident that the resulting speaker would behave only negligibly different than w/ the original crossover?

 

[pseudoid]

So to dumb this down (for me, perhaps others, too): one could substitute this crossover and be confident that the resulting speaker would behave only negligibly different than w/ the original crossover?

... to further dumb this down (for me, perhaps others,too): The DIYer would need an AudioPrecision and a Klippel, to be able to make a direct bahavioral comparison of the new x-over to what @amirm has already provided.
Otherwise, the change becomes but the lipstick.

 

[Inertiaman]

... to further dumb this down (for me, perhaps others,too): The DIYer would need an AudioPrecision and a Klippel, to be able to make a direct bahavioral comparison of the new x-over to what @amirm has already provided.
Otherwise, the change becomes but the lipstick.

Correct me if I'm misinterpreting you, but you seem to be saying only a direct acoustic comparison between a speaker w/ original XO and a speaker w/ alternate XO would be a valid assessment of the alternate crossover?

 

[Rick Sykora]

So to dumb this down (for me, perhaps others, too): one could substitute this crossover and be confident that the resulting speaker would behave only negligibly different than w/ the original crossover?

Correct. I have not personally loaded his crossover, but @kimmosto is the dev for VituixCAD and an experienced designer.

 

[XMechanik]

So to dumb this down (for me, perhaps others, too): one could substitute this crossover and be confident that the resulting speaker would behave only negligibly different than w/ the original crossover?

The original crossover gives noticeably more linear characteristics and has better suppression of midwoofer breakup resonance at 7kHz. Still, the simpler one looks like a reasonable compromise.

 

[Inertiaman]

The original crossover gives noticeably more linear characteristics and has better suppression of midwoofer breakup resonance at 7kHz. Still, the simpler one looks like a reasonable compromise.

Nice animations, thanks!. That's the objective summary I was hoping for. Clearly illustrates the differences, which I'd personally characterize as more than negligible, but certainly similar enough that the simpler 2-2-4 crossover is worthy of consideration.

FWIW, if I compare crossover cost using equivalent components (Jantzen CrossCap and Jantzen air coils in both cases) its ~ $25 lower (per speaker) for the 2-2-4 crossover. Also not negligible!

 

[AudioJester]

I will say something that we all already know.

The cost of DIY (parts, labor, tools, the mess you make in your facility) to build something that may or may not comply with industrial machine level precision is only worth it if you enjoy the task of building something of your own.

If you are like me, very handy, but don't enjoy doing that damn work, go buy yourself an Ascend and be start listening immediately.

This is a very strange post?

Its like if I post in the Ascend review thread-
"Or you can save a heap of money money and have the self-fulfillment/joy of DIY with a superb measuring Mechano23"

 

[bunkbail]

A question to the designer @XMechanik, why is the paper woofer being chosen here and why not the aluminium counterpart (SB15NBAC30-4)? Is it because of the target cabinet size? The aluminium woofer digs down lower and according to some measurements out there has much lower distortion than the paper version.

 

[Inertiaman]

A question to the designer @XMechanik, why is the paper woofer being chosen here and why not the aluminium counterpart (SB15NBAC30-4)? Is it because of the target cabinet size? The aluminium woofer digs down lower and according to some measurements out there has much lower distortion than the paper version.

I'll let @XMechanik give his rationale, but I'll point out that the driver you referenced is not an "aluminum counterpart" to the SB13PFCR25-4. Its a completely different driver: 15cm vs 13cm, 30mm VC vs 25mm, and 2X-3X higher price, among other distinctions.