Auratone DIY

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Hi All

I'm going to build one of these too - just wondering for the folks who used chipboard, what density did you use?
Perhaps this doesn't matter tremendously, but thought I ought to ask as I assume the type of wood will make quite a difference to the response of the cabinet.

Cheers!
 
Cymatics,

I used bog standard chipboard, not MDF.  I think a "dead" material like chipboard is best as it does not conduct sound like solid wood; the particles find it hard to transfer vibrations to other particles.

The cabinet is so small and stiff that panel vibration is not an issue.
The corners are pinned and glued with 20mmx20mm pine, that does make it stiff.
The back is screwed on to the 20mmx20mm, and there is a gasket to prevent air leaks.
good luck

DaveP
 
Thanks Dave!

Perhaps I'm overthinking all this, but I put together the cabinet as a model in Sketchup just to check dimensions and think through the construction (it helps me to visualise it!). Do I have the internal bracing layout correct, or correct enough? I calculated the internal dimensions and it works out at 2.152 Litres (using 20mm softwood/pine internal struts), so a bit under the Auratone's volume, and that's not factoring in the speaker driver itself (not sure if that was factored into your estimate). But perhaps doesn't matter!

Pic of model here:
http://i.imgur.com/8eopE.png
 
Cymatics,

That sketch is very good, I put quadrant in the corners to fill that gap you show.

I made the front panel a little larger so that I could put the 20mm section around the speaker as well.  Otherwise its as your sketch.  The volume is so far from optimum that tiny variations are not a big deal, in fact the BAF (Bonded Acetate Fibre) has the property of increasing the effective volume by 10~15%, so I understand.  The object is not to eliminate all the cone's rear output, but to dampen the reflections between the panels, so just line it, don't fill it.

best
DaveP
 
Hi Dave, Hi all,

My London musicians connection succeeded to help me to get the speaker delivered to Munich.
I received them yesterday. They will be working in my home studio soon:
https://sites.google.com/site/soundtwister/
Are you against MDF for the wood?
I still haven't understood what are the :Bonded Acetate Fibre, and chipboard...

Thank you,

PK
 
Here's what I ended up with:

davetone-complete.jpg


Details available on my DIY blog. I guess the internal cubic volume is slightly larger than on Auratones, but I didn't bother making exact calculations.

Thanks for project Dave, will be interesting to test these on various mixdowns :)
 
Hi,

I noticed that Maplin sells the loudspeaker on Ebay:

http://www.ebay.co.uk/itm/51-4-60W-SHIELDED-BASS-MID-SUB-WOOFER-AUDIO-HiFi-SPEAKER-NEW-/320777079704?pt=UK_Sound_Vision_Speaker_Parts&hash=item4aafcdcb98#ht_2208wt_1141

Now, it is easier for European people to get them...

Regards,

Francois
 
Ohh... I am very sorry, I didn't see that... Very sorry.
I think the solution would be to do a group by...
I can check with my english connection if he would be agree...
But it would be necessary to "increase" the price and to do a group by until a certain date.
I gave him 50€ just to organize ALL... THe ordering and the shipping/ going to post office.
If you feel interested into that solution, just make a repply to this post adding the quantity you want.
I will check with the friend if it would be ok for him like this.
 
Best regards,

Francois
 
Ok, I make a list. And will propose my friend. I received the speaker last friday. As I wrote, Just to thank him for the help, I sent him the money, 50€. I guess it was correct concerning the time, etcc.. used by the ordering/shipping... Packing... It's time burnt...

If we can make a small list, he can estimate the advantage of doing this, and agree to do the job.

I have the speaker now, I am happy, but still need to box them.

I will keep you informed.

Francois
 
El-Bee,

Very nice looking modern speakers, I hope they sound as cool as they look!


Polykobol,

Chipboard is made from chipped wood with the particles being say 5mm across.  They are mixed with a little resin and extruded out as flat sheets, they are commonly used in interlocking form for flooring.  Chipboard is very cheap and non resonant, making it ideal for speaker cabinets.  MDF takes it one step further and reduces the wood to fibres, hence, Medium Density Fibreboard.  This is also non resonant but more expensive, but the finer texture makes more precision possible.  It is advisable to use a mask with MDF due to the fibres and the binder which contains formaldehyde.

BAF or Bonded Acetate Fibre is commonly used for filling duvets, pillows and cushions. It is harmless and ideal for filling/lining speaker cabinets.  Its cheaper to buy a cheap duvet than to buy it from a speaker company.

This project keeps on going...amazing!

best
DaveP
 
Hm,
still, the optimal solution for now and the future, would be to find one or more commonly available equivalent speakers.
UK without official export, is a bit discouraging.

It should not be all too hard, to find and post possible alternatives. but would be far better to maintain this project.

The main points, why this project is so successful and gains so much attention, are:

It is very cheap.
The commercially available alternatives are wayyy overpriced (even the Behringer clones are...and, not surprisingly, they work for what the auratones are meant to be used - balance your mix by checking the mids only)
It is very useful nevertheless. In fact you may listen to it for a long time in future.
Therefore it is a *very* rewarding DIY project.
Not much, what can go wrong with it.
Kind of a must-have.

Therefore - wouldn't it be more useful to concentrate on searching for chassis alternatives (like DaveP himself did!) instead of organizing group buys?
I guess many of us around here would not hesitate to build a pair of these babies...
Not only today but also in future...
This one could be an evergreen groupdiy project, because it is also perfectly suitable for diy newbies.

Best regards,
Martin



 
Hahaha,
i just had a look into the data for my dirtcheap "cross-checking-worst-case-mids" hifi speakers, where i just closed the reflex tube to get it 'dry' and make them much better than ever expected.
http://www.hifi-selbstbau.de/index.php?option=com_content&view=article&id=194:dynavox-tg100b&catid=51:fertiglautsprecher-umbau&Itemid=82

Interestingly, the price today is more than twice as much as I paid :)
For a reason I guess...
LOL.

But back to the Auraclones...
Main problem to find alternatives is, that you nearly never get the TSP from the seller, as long as we are talking cheap speaker chassis.
Even if you do so, the TSPs that you are given is nothing like that, what you measure. There are easily up to 20 or even 25% difference possible, at least in some parameters. And the TSPs also change over the time the chassis is being used. And those changes might not be subtle at all.
So, we are just using the datasheet values as 'somewhere in the ballpark'-values.
To measure TSPs of a chassis you own, experimentally, we could use the german program 'hobbybox' or the ARTA software package or whatever you might have at hand.

(Just a few loud thoughts.... please chime in with your ideas....)

BR,
Martin



 
HI all,

Just found this thread and I am inspired to follow suit and get my tool belt out...

Just thought I'd post this for the sake of completion, it's the SAE magazine link with the Auratone Response curve that DaveP Mentioned.

http://alumni.sae.edu/wp-content/magazin/SAE_Magazin_1_2009.pdf

The specs are on page 63

Feel free to sticky this in to your Original post dave for the ease of all users...

Drew.
 
Thanks drewbang,

I've extracted pages 62&63 and attached to original post.

best
DaveP
 
Hi All

Still have to fit the Quadrant, but screwed in the cone today, and fired it up! Worked first time. Thanks for the tips Dave, and for the original heads-up! I agree with the other poster as to why it's doing so well: it's cheap, simple to make, useful and sounds pretty good actually.

Video here: http://www.youtube.com/watch?v=v2dB2B4jet4

Cheers
 

Latest posts

Back
Top