Bookshelf Speaker Cabinets

#1

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Hi All,

I am looking for some help building a pair of hardwood bookshelf speaker cabinets. I’ve had the basic woodwork induction but I need some additional tools to create some panels from rough sawn beech. So this is basically a callout for a capable friend to help me? I’d love to collaborate with someone who’s made up wooden panels before to get some guidance, learn from them and be able to make progress on the project whilst waiting for table saw and thicknesser inductions.

I’m not working at the moment so very flexible with times and I’ll offer up the handsome reward of post-build beers on me at canopy!

Let me know if you’re interested!

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#2

Hi Chris. If you see me in the space, I’ve always got time for tips and pointers.

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#3

Great project! You’ll learn a lot!!!

Please forgive and forget what I’m writing now, if you don’t mind the sound quality of the finished product. This is my tuppence from being an audio nutter. :laughing:

Disclaimer: Only keep reading if you’re an audio nutter like myself. I’m not a high-end idiot, but I spent many years in recording studios in front of studio monitors - so… that’s why I call myself an audio nutter.

You are aware of the resonance problem when building speaker enclosures from hardwood?

If you’re building a musical instrument, hardwood is the way to go… well, it has been for many, many centuries. Resonance is embraced, but not when building speaker cabinets - resonance is your enemy.

You will be using some form of absorbing material inside the cabinets for the high frequency reflections of the wood, but when using hardwood for enclosures in bookshelf dimensions, you will very likely be experiencing a lot of 120-280Hz and 400-800 Hz resonances, depending on the material and the dimensions. This could potentially make them sound a bit dull, even with very high quality drivers.

An affordable alternative would be HDF for the cabinet and slab veneer onto it, if you’re going for the look.

Practically, you’ll only notice the difference when comparing the speakers to another set of speakers. Most people are fine with an 8 pound radio made of plastic. This is only important, if you want to make the most out of the finished product.

Again, I’m fully aware of being the party pooper. No worries if go ahead and build the speakers from hardwood and I’m sure they’ll look and feel phenomenal! If you’re not a sound nutter, then you will have an absolute beast of a project! Some further reading material on resonances…

Please share pictures along the way!!!

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#4

Looks like @Riggerz and @Chrispyduck could be MakerBuddies for this project?

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#5

Thanks Brendon. I met Chris today at the table saw induction. Passed on some advice and told Chris about my availability. Fun little project. Glad to help.

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#6

Thanks for sharing all that knowledge, really appreciate the input from people with this depth of understanding. I would stop short of identifying as an audio nutter but I am well aware I’m not following the best practice. I’m definitely aiming to make something that sounds good but, making it out of hardwood is a design constraint to be worked within on this one.

After looking at the material you shared and doing some further reading it does seem like I might be able to mitigate some of that unwanted resonance by adding internal MDF bracing? I’m also expecting to end up with panels that are close to 1 inch thick, the information on linkwitz makes it seem that this could go either way depending on stiffness vs weight but I’m a tiny bit optimistic about it if theres sufficient bracing.

Definitely open to getting more input though. Even if I don’t follow it in this project I’d love to have the information. And will definitely keep you posted with pictures!

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#7

If this is the first set of speakers you’re building - I would recommend, just go for it and enjoy building the project. The disclaimer I used was meant seriously. This is only relevant, if you plan on putting drivers >= £400 into the cabs. The reason is simply, that you might end up with speakers that have either too much or too little low end, which then you might try tweaking in the crossover, but then other frequencies might sound dull/harsh… and end up chasing a squirrel.

95% of the time, you’ll end up with a very decent set of speakers, whatever material you’re going to be using. Go for it, as I said, you’ll learn a ton of stuff from the woodworking experience alone. And you’ll end up with something unique that you’re going to be proud of.

As for reinforcing with MDF… I’m a bit “meh” about that. What would be awesome, but also even crazier nerdier, would be building the exact same speaker cabinet from HDF and from Hardwood, then have a shootout! :slight_smile:

Since I opened that can already, there are studio monitors built by the BBC that were deliberately designed to resonate at specific frequency ranges. They were tuned - like a musical instrument.

Then there is the current meta in speaker design which is DSP controlled, so no need for expensive acoustic treatment in your studio, like Kii Audio does.

Seriously. Make it, don’t worry about the nerd-factor!!!

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#8

Hi @Chrispyduck I’ve built some before and would be happy to help.

Is there any reason you are using hardwood instead of something more acoustically dead like MDF?

For the Baffle I’de considering using the CNC given we have one :blush:

1 Like
#9

Thought some of you might enjoy a little update of progress so far…

I ended up getting a very nice piece of Ash for the sides of the boxes and some sapele for the baffles. So far I’ve prepared the sides, the rear panel and a ring brace which I am hoping to glue up tomorrow. Then will machine the front baffle once the glued up size is known to get a nice clean fit.

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#10

Looking really good, makes me want to remake my classic ii’s

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#11

Machined the baffles on the big CNC last week and got a nice timelapse! Please forgive the embedded instagram post, couldn’t figure out how to upload the raw video…

View this post on Instagram

A post shared by Chris Paine (@chrisjackpaine)

After they were machined I was able to plane and sand the edges down to fit and I’m really happy with the results:

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I’ve since attached the blanks for the ports on the rear of the baffles, will probably have another video showing that process soon!

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#12

Looks great!

Can we get up a SLMS logo / name where the canopy sign is?
No sense in advertising a beer company instead of SLMS!

#13

Yes, that was just a test… will swap in a slms one!

#14

Was great to read this post and see others interested in speaker building here!

I’m planning to build a pair myself, and although no professional, I’m interested in learning the nerdy stuff and hearing any advice from the community.

Mine are going to be in addition to some I previously built to create a miniature “sound system” kind of stack. I’m new to building so keeping a pretty rustic raw look suits my skills, or lack of!

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#15

Hi Chris,

We are starting to look at our content inclusion for the Dulwich festival Maker fair we have a “Don’t be Shy! submit your Make” event happening on Friday. Would this be of any interest to you maybe and/or do you know anyone else I can reach out too?

Cheers
Dorine