Done my Atlas 15 Project!!! (well no paint yet... bah)

michael_w

Well after much waiting for the damn sub to actually get here I have completed my first diy speaker. That whole month of waiting was tough but it's done now.

For those that didn't see any of the earlier threads discussing this:

I am building my first diy sub using an Ascendant Audio Atlas 15 (on sale of course ) coupled with a Creative Sound Solutions Sub250RF plate amp that puts out 360 watts into 4 ohms. It will be downfiring (ports and sub)

The project was interesting as I am new to this and generally things tend to go wrong. (only a couple things went wrong and were fixed) I had my dad help me with things such as the cutting using a panel saw but I pretty much did everything.

The original plan was to coat it with black truck bed liner but I did a couple test coats on a scrap piece of mdf and it looked horrible. I was expecting a smooth pebble / bubbly like surface but instead it was like black sandpaper. I decided to screw that idea and just install everything while it is in its naked mdf state until I find a better finish.

One thing I was pleased to find out was that on the little volume / crossover control that I mounted on the front it has little leds to let you know where the knobs are at. I knew about the leds but I had no idea that they were red when the amp was off and green when it is running. (plus having a remote for my sub is so fun )


This thing is a beast.... It's absolutly huge in my 8' by 13' room. Weighing in at around 100 to 120 lbs it's not exactly the easiest thing to move. I had just finished installing everything (amp, sub, xover/vol control box thing) and it was upside down so I tried to roll it over onto its casters. Well one of the casters shifted right before I was almost there and BAM I shattered one of the 1-3/4 high mdf legs. That didn't take too long to fix but let me know to be a tad more careful when moving this thing onto its feet.

Sound
I'm amazed how this thing sounds.... I've never heard bass quite like this. I havn't auditioned too many subs but I have heard ones in the $1000 range and this just blows them away. I have never heard so much stuff in my room vibrate and rattle ever before. The effortless rumble and punch is crazy... maybe I'm too used to a little tiny 8" Athena sub but I'm awestruck with this sub and it's ability to fill a room. It's much much cleaner than my old athena and seems to spread through the room... a presence of bass instead of knowing that a sub is playing at the front somewhere. I measured spl a couple times and noticed that it isn't louder than the athena but it sounds and feels much louder. (probably because it is cleaner and hits much lower)

Well I hate to say it but my mom has the digital camera at her house so I have no pictures of the final construction or of it sitting in my room . I'll post pics as soon as I get ahold of the camera. It didn't make my original dedline of my birthday (June 8th) because of the sub not getting here until a few days ago but I'm happy enough now to compensate for the lateness

Early B.

Ha Ha Ha. Sounds like you're having a ton of fun with your sub. Great to hear you're enjoying it. How many cubic feet is it?

BTW -- you gotta put a couple of coats of paint sealant on the MDF before you apply the truck bed liner. Lots of options at Home Depot. I used Zinser. Works great and dries super fast. After you do that, the truck bed liner works great. Very easy to apply. You'll need at least two cans of it.

michael_w

Yea I didn't try it with a sealant first. I'm just really not crazy about the little tiny granuales... it makes it look and feel like coarse sandpaper only using small granules.

The box is 6.5 cubic feet. Outside dimensions are about 23" high, 23.5" wide and 25.5" deep without the feet and casters. Here is a drawing I drew up before I made it (made with autocad r14)

~ Link ~

So far I'm still amazed about this kind of bass in-room... I've heard similar but much sloppier in car systems but nothing close in a ht / stereo setup. My first step into real subwoofers Also I have noticed that it has increased the soundstage. I think this is because it is going lower and throwing those omnidirectional notes all through my room. I've retired my old sub to computer duty now

goingganzo

if it is anything like my avalanch setup you will love it.

dorokusai

Excellent.

gatemplin

Congrats. Now that you've caught the DIY bug, considered moving on to speakers. The CSS WR125s sound really good. I'm considering them for dorm speakers myself.

michael_w

I'm not quite sure it'll stand up to 4 avalanches but it's good enough for my tiny room

I do plan to get into speakers and stuff like that. At the moment I am waiting to begin a speaker project using two 3" audax drivers per speaker. The speakers were very generously given to me when I went to the Northwest Audio meet. They will be for my computer and be powered by a sonic impact t-amp thingy. (which I plan to do a couple minor mods too eventually)

I've heard the CSS WR125s and I agree they are very nice speakers. $63 each... so for under 150 you can make some kickass bookshelves. I've heard a couple pairs of small bookshelves and they are very decent and definatly good bang for buck.

Heres the Audax HT080M0. I plan to stick them in a ported 0.2 cubic foot box.




Here is the box I drew out on autocadd

3d View
Side View


edit: stupid geocities not letting me use enough bandwith with my pictures (they will show up again eventually)

gatemplin

That seems like a good project to start with. You'll learn a lot and it will cost next to, or maybe nothing.

I wish I lived out west so I could get to those DIY meets. Glad you had a good time.

michael_w

Thanks, and yes that's my goal... to learn as much as I can since I'm new to all this fancy diy stuff.

Heres a response graph of the Audax box that I created with unibox. Sorry for the size.... it seems to get all unsmooth when I resize graphs and autocad drawings.

It looks pretty flat overall to me, except maybe that little peak right before it drops off.

gatemplin

It says your Vb is 58L. You want around 1L I would guess.

3" drivers usually have trouble that low (80 Hz), even the Hi Vi or Aura drivers with massive Xmax.

What are you using for resizing. I dont have a problem when using Photopaint to resize AutoCAD or Unibox plots.

michael_w

updated graph... I guess last time I ran unibox I didn't save after I changed a couple things. Now it's set for 5.7 L (0.2 cubic feet).

I use photoshop 7... here is a resized one and it doesn't look too great.

cool post number 666

michael_w

In spite of maybe angering someone from resuructing a really old thread I wanted to share some pics of what it looks like now that I have finally painted my sub.

I first went through a can of acrylic enamel paint and it didn't look too great. My original plan was to use the truck bed liner stuff but I really wasn't crazy about the test sample I did (had 2 coats of the acrylic stuff then 4 bed liner coats and still looked bad). I sort of just wanted to get it done so I picked up some black laquer and sprayed that on. After going through two cans of that this is what it turned out to be... not ideal but better than raw mdf.

btw sid might smack me for this but I decided to put polyfill in it after talking to one of the engineers from adire audio for a while at the northwest audio meet.

VR3

Nothing wrong with Polyfill... I recomend it or foam pads... I feel it is something that every speaker needs atleast a lil of...

Sub looks KILLER dude... excellent job... very pro looking... I bet it slams too...

Congrats!

michael_w

It doesn't look quite as good as it does in the pics when the light hits it just right but it'll do. It also does quite nicely to shake my 8' by 13' room

PolkThug

Good job!

hoosier21

great project. looks like it was well worth your time to DIY.

janmike

Beautiful job Michael. What do you figure you have invested in such a project. As well, is the box material important or can you use any type of wood product. Would real wood work better than MDF?

gatemplin

janmike wrote:

As well, is the box material important or can you use any type of wood product. Would real wood work better than MDF?

For enclosures MDF is better than real wood. It is very dense and consistant. Void free Baltic birch 13 layer ply is considered better than MDF though.

Great job Michael. Turned out very nice. I bet it sounds great too.

VR3

Real wood is ok if you have something like plywood or mdf behind it.

But real would expands and contracts over time with the enviorment it is in, and it eventually splits. This could lead to major air leaks...

MDF and plywood is the way to go, if you do 45 degree cuts, you can use plywood all the way around and make an absolutely gorgeous speaker.

michael_w

Pricing on this Project (In Canadian $$)

Ascendant Audio Atlas 15 --- $137.41
Creative Sound Solutions SUB250RF (360 watts into 4 ohm plate amp) --- $272.46
One (1) full sheet of MDF --- about $35
Two (2) 4" flared ports from CSS --- $50.16
4 lb bag of polyfill from wallmart --- about $10
half metre of tull to cover ports --- around $1.24
small box of screws for ports --- around $3
3 cans of spray paint --- around $16 (two of which I got at cost)
Two (boxes) of 75lb casters (2 per box) --- $13
PVC Cement --- around $8
Woofer mounting kit from CSS --- Bob threw that in for free but usually $7.98

Total Cost: CDN --> $546.22 USD --> $452.32


I went a little crazy on the plate amp and could have bought the cheaper one that put out 150 watts into 4 ohms (priced at 129 cdn) but wanted to give the sub what it deserves. Plus that remote and seperate volume / crossover box is so fun and handy.

michael_w

Mdf is used so often because it is said to not have any grain so it stays as neutral and consistant as possible, where real wood will have grain and be much harder to build two speakers that are similar (plus mdf is much cheaper). I'll probably build my next speakers out of mdf and plywood because when stained plywood can look really really nice.

btw thanks for the compliments.

gmorris

Nice job with the Atlas 15. I built a 9 cubic foot Sonosub with my Atlas 15, and I am hearing the same great bass as you.

One question? Where the hell did you hear particle board is one of the best woods to use for building speakers?

michael_w

I thought about doing a sonosub but strayed away from that since I don't have the room height wise.

I think someone here said that particle board was actually better than mdf, but since it pretty much falls apart when you cut it is wasn't so great. Just passing on bad knowledge... start ignoring me now lol I thought that it was super crappy and a cheap way out of making speakers but then heard differently here. Speaking of particle board my monitor 7's are actually made out of the stuff. I've thought about making replicia cabinets but much beefier for my monitors but don't want to mess with the original glory of vintage speakers.

hoosier21

michael_w wrote:

I think someone here said that particle board was actually better than mdf, but since it pretty much falls apart when you cut it is wasn't so great. Just passing on bad knowledge...

Where is the source of that information, because particle board is a joke.

michael_w

Alright did a search and couldn't find anything... must have been a really long time ago or I read it wrong. Edited out bad info

VR3

That was DKG on the Monitor rebuild. (I have no clue how I remember that)

Particle Board is NASTY, it contains courser material, which leads to material that isnt near as dense as MDF. If you cut MDF, Medex, Medite up - and look at the side, it is solid, 100% - you cut Particle Board up, you can see holes... everywhere. It's lighter weight and not near as dense...

MDF all the way!

michael_w

That's probably where I came up with that idea. Thanks for pointing that out.

dkg999 wrote:

MDF will come flying apart into chunks and fluffy stuff if you run it thru a high-speed planer! This is from personal experience, and not the good kind! There is particle board, which in cabinet grade is pretty good stuff, weighs in at 90 lbs for a 4x8 sheet, and their is OSB (oriented strand board, also called wafer board), like they use for underlayment when building a house. For speaker and cabinet building, particle board good, OSB board bad. The problem with MDF and particle board when it comes to high speed tools such as router bits, saw blades, and planer blades, is the high glue content. It just burns and eats away at your blades. Too slow, and you are burning tooling and the work piece, too fast and the density of the materials heats up the motors on your tools.

also

dkg999 wrote:

Sid - now I am confused. Particle board is a higher strength and better cabinet construction material than MDF. Why would you rebuild a set of cabinets made with particle board in MDF? If you are that bored, build a new set of speakers from scratch! You can try resawing the MDF, but I am guessing the result won't have enough structural integrity to do what you need. You can buy small 2x2 or 2x4 pieces of oak plywood at the big box stores that won't cost you $50.

originally from ~link~

I guess I didn't quite follow the thread long enough