A thread for me to dump stuff into. - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #1 of 47 Old 08-15-2007, 02:54 AM - Thread Starter
Advanced Member
 
Shinobiwan's Avatar
 
Join Date: Dec 2003
Location: UK
Posts: 589
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Instead of posting bits scattered throughout this forum I thought it would be better and easier to keep them in one place.

I receive the odd PM every now and again asking about finishing and spraying so I'll keep to that for now and try to help others out with questions should they have any.

Everyone likes videos and a static photo will only tell half the story. So to better illustrate the paint jobs I'm talking about here's a couple of videos I've taken of my current project:

Sparkle effect over baffle(1.7Mb)

High Gloss Finish(3.3Mb)

You'll need the divx codec installed onto your computer. If double clicking the files doesn't work then drag on drop them into your media player. If you don't have divx then I recommend downloading and installing ffdshow.
Shinobiwan is offline  
Sponsored Links
Advertisement
 
post #2 of 47 Old 08-15-2007, 11:50 AM
AVS Special Member
 
ssabripo's Avatar
 
Join Date: Feb 2004
Location: Plantation, Floriduh
Posts: 6,009
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 15
well done Shino! this will be very handy my friend!
ssabripo is offline  
post #3 of 47 Old 08-15-2007, 01:00 PM
AVS Special Member
 
TheEAR's Avatar
 
Join Date: Nov 2006
Location: Montreal,CANADA
Posts: 3,464
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Exquisite finish,bravo...

What did you use to cut the baffle ? CNC machine?

Ask yourself mortal , do you have as much displacement as me ? The answer is no unless you have a Windmere fan sub.
TheEAR is offline  
post #4 of 47 Old 08-15-2007, 05:47 PM
AVS Special Member
 
exojam's Avatar
 
Join Date: Dec 2004
Location: MA
Posts: 2,554
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 29
Sorry but the first thing out of my mouth when I saw the pictures was "holy crap". Man I wish I had 1/10 of your skills on this kind of stuff. Very nice indeed.
exojam is offline  
post #5 of 47 Old 08-17-2007, 12:06 PM
AVS Special Member
 
Ricci's Avatar
 
Join Date: Mar 2007
Location: Louisville KY
Posts: 5,155
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 53 Post(s)
Liked: 248
Shinobiwan,

Spectacular job.

How long have you been working on these? Planning, building, etc?
Ricci is online now  
post #6 of 47 Old 08-17-2007, 12:41 PM
Advanced Member
 
geoffstgermaine's Avatar
 
Join Date: Jan 2007
Location: Winnipeg, Canada
Posts: 504
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Amazing work. Those are stunning. Probably one of the best looking speakers I've seen. I can't wait to see them finished.
geoffstgermaine is offline  
post #7 of 47 Old 08-17-2007, 01:05 PM
Senior Member
 
Wildcard26's Avatar
 
Join Date: Apr 2006
Location: Trinidad and Tobago
Posts: 333
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Just the other day I was wondering about the progress of this project and wanted to ask but didn't want to come across more impatient than the builder. Exquisite work indeed Shino.
Wildcard26 is offline  
post #8 of 47 Old 08-17-2007, 01:08 PM
Advanced Member
 
The_Dark_Knight's Avatar
 
Join Date: Mar 2006
Posts: 825
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Wow.

That's probably the best DIY speakers I've ever seen.

Great design and craftmanship.
The_Dark_Knight is offline  
post #9 of 47 Old 08-17-2007, 09:26 PM
Senior Member
 
stevdart's Avatar
 
Join Date: Apr 2006
Posts: 471
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I realize now that my DIY speakers look, well...homemade. I'll be studying your methods before my next build. Great work!
stevdart is offline  
post #10 of 47 Old 08-18-2007, 03:07 AM
Advanced Member
 
terry j's Avatar
 
Join Date: Aug 2006
Posts: 866
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 14
yes, they are absolutely stunning.

Funnily enough-don't laugh now- I reckon they look great even in mdf!

What I did want to ask shinobiwan, I've noticed in all pics of your different builds the use of EXTENSIVE bracing!!

Is hat just because of it being a case of 'if you're going to do a job , you may as well do it properly' or is it based on personal experience of the benefits of a well braced box over a less well braced box?

If so, would it be too much to ask you to give a brief account of those experiences?? And of course if it is based on 'hearing' the benefits, could you also give us an insight into whatever 'rule of thumb' you apply in deciding where and how to brace the box.

I'm still learning you see!!

thanks
terry j is offline  
post #11 of 47 Old 08-18-2007, 07:28 PM
AVS Special Member
 
jmcomp124's Avatar
 
Join Date: Feb 2002
Location: Portland, OR
Posts: 3,600
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 18
I could go on and on with lengthy words of appreciation but all that I can say right now is that to my eyes, "this is the benchmark of DIY speakers".
Simply, exquisite piece of work showing tremendous amount of patience and passion for the work.
Shinobiwan,
You will have many years of pleasure looking at your accomplishment and I am sure pure listening pleasure too. Kudos
Enjoy.
jmcomp124 is offline  
post #12 of 47 Old 08-18-2007, 07:36 PM
AVS Special Member
 
Rayjr's Avatar
 
Join Date: Jul 2002
Location: So. Cal.
Posts: 1,725
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 53 Post(s)
Liked: 117
Send a message via AIM to Rayjr Send a message via Yahoo to Rayjr Send a message via Skype™ to Rayjr
Shinobiwan,
I think that you are an artist...

RayJr
Rayjr is offline  
post #13 of 47 Old 08-18-2007, 08:58 PM
Advanced Member
 
Habs4life's Avatar
 
Join Date: Apr 2006
Location: Ontario Canada
Posts: 617
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Rayjr View Post

Shinobiwan,
I think that you are an artist...

He sure is,those are spectacular.To get that finish has got be extremely time consuming and obviously the results show it was time well spent.
Habs4life is offline  
post #14 of 47 Old 08-18-2007, 09:08 PM
AVS Special Member
 
jmcomp124's Avatar
 
Join Date: Feb 2002
Location: Portland, OR
Posts: 3,600
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 18
Quote:
Originally Posted by Shinobiwan View Post

First off thanks for the kind words.

To answer your question, yes extensive bracing is immediately noticeable. Its not always a large difference depending on what your comparing it to but it is always noticeable over a lesser braced boxed.

The most apparent effect is that the sound moves away from the speakers and associated boxes. This is natural because a greater percentage of the sound energy being radiated into the room is coming from the drive units. The cabinets have less sonic signature, don't add anything objectionable and don't radiate sound into the room alongside the drivers.

One of the reasons why small bookshelves sound great and do the imaging and soundstage thing well is because their cabinet are less resonant than an averagely built floorstander.

Whilst constructing, my rule of thumb is sub-divide the space within an enclosure as if your building a small standmount. So I normally work with a brace-to-brace spacing of no more than 20cm and normally 15cm. If you combine this with a matrix bracing format as well as laminated MDF wall construction of 9mm + 18mm MDF then you end up with something that overcomes many of the resonance issues associated with enclosures. You can go further with this too by adding mass loading to the internal walls.

To illustrate what your dealing with here are some accelerometer tests taken of MDF in various states of bracing and treatment. BTW an accelerometer is a small measuring device that attaches to a surface and measures seismic vibration within the material.

Here is 18mm MDF unbraced:

You can clearly see the rather hefty broad Q resonance at 190hz and the narrower Q of the 600hz one, both of these really extend in time smearing the original signal wreaking havoc on midrange clarity and giving a cupped and nasal character to vocals whilst slowing upper bass making it sound boxy and compressed. The good news is that sub builders have a nice material as there's not a whole lot going on down low.



Now take a look at 18mm MDF with 15cm brace-to-brace spacing:

Notice how the resonances have shifted up in frequency by over an octave or double the frequency. Not only that but the initial level the resonance and the following decay has improved too. This is all natural since your stiffening the whole box structure with the bracing. The trick here is to raise or lower those resonances out of the operating range of the driver that sits in the box. For my project show here these need to moved out past 1.5Khz where the midrange crossed to the tweeter and/or lowered significantly.



Finally take a look at 18mm MDF with the bracing shown above but also with mass loading added by way of using heavy lead sheet attached to all the internal walls. This is what I use in my midrange enclosure:

A remarkable improvement over just 18mm MDF and doesn't get much better than this unless you start looking into using concrete, multi material laminations or composites:




So its clear that for the most important mid frequency range you should take things a step further and build up a multilayer material approach such as I did for this project with 9+18mm MDF, 2mm lead, 2mm bitumen, 10mm acoustic foam. The subjective and objective differences these details make over an untreated and poorly braced cabinet are pretty massive with the latter sounding very much like a loudspeaker reproducing music and the former being much more natural and having realistic timbre and tonality that can fool you into thinking your listing to the real thing at times. Basically every facet of the sound improves to some degree when the box construction is right, there's not such thing as overbuilt here.

Hope this helps.

Shinobiwan,
This information sure helps. When I had my cabinets built by a cabinet maker (a big no no in your books) I had extensive bracing in mind, but he didn't do exactly what I wanted. However, my subs are double layered (3/4" mdf outside and 3/4" ply inside and an additional layer of mdf at the bottom) and reasonably braced. I was worried about resonance and coloration, but interestingly, the subs sound sooo good that they are very identical to the dual JL f113s I had in terms of sonic signature, but with much higher output (headroom) and lower extension.
I think I got away with less than optimal bracing because I am dealing with sub 80Hz material. If I ever end up building mid-bass modules or main speakers, my benchmark for construction is going to be yours .
Thanks for the useful info. It explains why "less than optimal bracing (in my definition)" still worked out well for me
jmcomp124 is offline  
post #15 of 47 Old 08-18-2007, 11:38 PM
Advanced Member
 
terry j's Avatar
 
Join Date: Aug 2006
Posts: 866
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 14
wow, that was a better reply than I had any right to hope for!!! Thanks mate.

The attached graphs certainly help visualise what you're talking about.

Can I extrapolate from your answer that the CRITICAL one to get right is the mids?? Somehow I don't think that would be the correct conclusion when I think about it, the stresses on a box are greater (surely) from the woofers, and in most three ways the mids are in the same box as the woofer, hence as your pictures show brace extensively.

Thanks for the effort in the answer, I'm sure that I'm not the only one to appreciate it.

Interesting when you spoke of a laminated MDF wall. The way you have said it seems to imply that a lamination of say 18mm + 10mm will give better results than a solid 28mm. Why would this be so??

I must admit I've thought of this too, but the idea I had was that instead of using something like PVA which would make a rigid lamination, what if we were to use for examples sake only, silicon. Not excessive amounts so that some sort of 'air gap' exists between the layers, but a good bond which unlike the rigid PVA one, there is some sort of internal resilience or give between the two layers. I wondered if that would mean it could actually absorb more energy with the internal friction between the layers than the solid rigid bond which will simply transmit the vibrations to the outer layer unchanged, ie less attenuation of the transmitted energy in the rigid structure than the one with more 'give'.

Does an idea like that have ANY merit I wonder.
terry j is offline  
post #16 of 47 Old 08-19-2007, 08:21 AM
Member
 
n3tfury's Avatar
 
Join Date: Feb 2005
Location: AZ
Posts: 112
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
Stunning work to say the least. Thanks for the extra effort to share your knowledge.
n3tfury is offline  
post #17 of 47 Old 08-19-2007, 11:05 AM
AVS Special Member
 
Raymond Leggs's Avatar
 
Join Date: Jul 2006
Posts: 3,612
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
The speakers can NEVER be too big!

One shall stand... One Shall Fall... - Optimus Prime
Raymond Leggs is offline  
post #18 of 47 Old 08-19-2007, 01:44 PM
AVS Special Member
 
Raymond Leggs's Avatar
 
Join Date: Jul 2006
Posts: 3,612
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by Shinobiwan View Post

Glad you enjoyed the pics.



Oh so true. If your a bloke that rule holds water no matter what the situation

LOL

One shall stand... One Shall Fall... - Optimus Prime
Raymond Leggs is offline  
post #19 of 47 Old 08-20-2007, 10:01 AM
AVS Special Member
 
Jonomega's Avatar
 
Join Date: Apr 2005
Location: Alexandria, VA
Posts: 3,518
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Excellent resource, your posts continue to astound me in terms of text, pictures, descriptions, laymen terms so that most all can understand. I especially liked the accelerometer study you did, very helpful in understanding why you had to go through a lot of work. I look forward to your updates!
Jonomega is offline  
post #20 of 47 Old 08-20-2007, 11:04 AM
AVS Special Member
 
price3's Avatar
 
Join Date: Jan 2003
Location: Clemson, SC
Posts: 1,181
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
You should have just gone the whole way and machined these out of solid marble chunks....

Easily the best looking speakers I have ever seen, DIY or otherwise.
price3 is offline  
post #21 of 47 Old 08-20-2007, 04:27 PM
AVS Special Member
 
crackyflipside's Avatar
 
Join Date: Oct 2005
Location: Miami, FL
Posts: 2,186
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
crackyflipside is offline  
post #22 of 47 Old 08-20-2007, 05:47 PM
AVS Special Member
 
Jonomega's Avatar
 
Join Date: Apr 2005
Location: Alexandria, VA
Posts: 3,518
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
Originally Posted by Shinobiwan View Post

Thanks Jonomega but I really cannot take credit for the accelerometer based material resonance testing. That was performed by a talented Dutch chap who occasionally posts on DIYAudio forum.

For the full tests go to his website here (its in Dutch but Babelfish does can make vague sense out of all):

http://www.zelfbouwaudio.nl/index.ph...id=18&Itemid=2

Thanks!
Jonomega is offline  
post #23 of 47 Old 08-20-2007, 08:10 PM
AVS Special Member
 
armystud0911's Avatar
 
Join Date: Jul 2006
Location: Cincinnati
Posts: 4,423
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 14
Shin, you really need to get yourself a CNC machine, with the amount of cutting you do, it would be your best friend.
armystud0911 is offline  
post #24 of 47 Old 08-23-2007, 03:45 PM
AVS Special Member
 
Raymond Leggs's Avatar
 
Join Date: Jul 2006
Posts: 3,612
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
I thought the Cerwin vegas i saw when I was out of town were big! But that takes the cake. They look like skyscrapers! I prefer ported speakers though.

One shall stand... One Shall Fall... - Optimus Prime
Raymond Leggs is offline  
post #25 of 47 Old 09-01-2007, 07:23 AM
Advanced Member
 
terry j's Avatar
 
Join Date: Aug 2006
Posts: 866
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 14
geez shinobiwan

I hope you are as sexy as your gear!! I can just imagine someones reaction if they walked into my room with speakers and amps that look as good as yours, with me in their field of vision uugghhh, doesn't bear thinking about.

Hope the same fate doesn't befall you, (don't disillusion me) but in my minds eye i see an adonis listening to beautiful sound from beautiful gear ha ha ha.
terry j is offline  
post #26 of 47 Old 09-01-2007, 11:16 AM
AVS Special Member
 
Spezzy's Avatar
 
Join Date: Jun 2006
Location: Huntington Beach, CA
Posts: 1,403
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 13
Quote:
Originally Posted by Shinobiwan View Post

I know folks around here appreciate power amps so thought this would be interesting.

Its one of three amps that will eventually power the DIY speakers I'm working on. There'll be 10 channel of 300w into 8ohm with each channel dedicated to one of ten drive units spread across the pair of speakers. That's 3kw into 8ohm total just for the fronts.




Very nice amp. Are there guides to making amps on the internet?

"The choices we make define our lives, because choice, not chance, determines destiny"

They call me the 18 year old DJ Audiophile-upgradeitis infected-guy!
Spezzy is offline  
post #27 of 47 Old 09-04-2008, 02:05 PM
 
JBLsound4645's Avatar
 
Join Date: May 2006
Location: Bournemouth, Dorset, United Kingdom
Posts: 5,409
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Top marks all around stunningly well designed and assembled.
JBLsound4645 is offline  
post #28 of 47 Old 09-06-2008, 08:59 AM
AVS Special Member
 
TheEAR's Avatar
 
Join Date: Nov 2006
Location: Montreal,CANADA
Posts: 3,464
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
The old hammer and pliers are priceless,the hammer there when things do not fit.

Now shine that amp to a gloss to match the speakers.

Ask yourself mortal , do you have as much displacement as me ? The answer is no unless you have a Windmere fan sub.
TheEAR is offline  
post #29 of 47 Old 09-06-2008, 06:51 PM
Advanced Member
 
2100's Avatar
 
Join Date: Mar 2008
Location: Singapore
Posts: 729
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Bro Shinobiwan, this speaker is utilising the RAAL. But I think you sold the RAAL right? Care to share what are the issues with it? It seems that it only takes a really high-end customised RAAL to satisfy Romy. I have heard AMTs like ESS, Beyma TPL-150...still lacking what I want.
2100 is offline  
post #30 of 47 Old 09-06-2008, 08:17 PM
Advanced Member
 
2100's Avatar
 
Join Date: Mar 2008
Location: Singapore
Posts: 729
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Shinobiwan View Post

Still have RAAL's 140-15d and happy with them. No plans to swap.

My mistake!
2100 is offline  
Reply DIY Speakers and Subs

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off