open baffle project - Page 2 - diyAudio
Go Back   Home > Forums > Loudspeakers > Full Range

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 17th April 2007, 02:35 AM   #11
diyAudio Member
 
Join Date: May 2006
Send a message via AIM to mastarecoil
Partsexpress sells a finished 3-way crossover for $18, but is it just junk?
http://www.partsexpress.com/pe/showd...number=260-210

or these?

http://cgi.ebay.com/ELAN-3-WAY-PASSI...QQcmdZViewItem

http://cgi.ebay.com/1-PAIR-3-WAY-PAS...QQcmdZViewItem
  Reply With Quote
Old 17th April 2007, 11:08 PM   #12
holdent is offline holdent  Canada
diyAudio Member
 
Join Date: Nov 2005
Location: Ontario
Sorry I can't advise you well on crossover design. Generally, however, you get what you pay for.
- The first eBay xover, the Elan xover, has 1st order slopes (6dB), lower power handling, is set-up for a 4 ohm woofer, and has what looks like iron-core inductors = cheap and not very good.
- The second eBay listing is for a car audio crossover but the specs (other than general fequency range for each driver) aren't given. If I had to gues it also appears to have a 1st order slope for the woofer and 2nd order (12 dB) for the midrange? It also appears to have better (but low gauge?) air-core inductors = ??? who knows
- At least with the PartsExpress xover they provide almost all relavent info = probably a good deal for applications in an inexpensive OB

The more expensive Dayton and PartsExpress xovers are much better.

NOTE - this thread has strayed far from Fullrange application - You should look for and ask for help in the Loudspeaker diyAudio Forum (http://www.diyaudio.com/forums/forum...p?s=&forumid=6)
  Reply With Quote
Old 20th April 2007, 05:33 AM   #13
diyAudio Member
 
Join Date: Feb 2005
Location: USA
Holdent,

Would you mind sharing your crossover for the Silver Iris' plus the Alphas that you are using. I am planning to do the same with passive crossovers instead of spending money for plate amps.

Also you've mentioned using woofer with high qts - what does high qts do. Is it better for open baffle to select woofer that has high qts.
Thanks.
  Reply With Quote
Old 20th April 2007, 01:56 PM   #14
diyAudio Member
 
Viridian's Avatar
 
Join Date: Jan 2007
Location: Eugene, OR
Default Re: open baffle project

Quote:
Originally posted by mastarecoil
Hi all,

I am looking to do my first DIY speaker. Done subs, but want to try a nice pair of speakers now to use in 2 channel for mostly music, maybe 12-18" tall, so its easy to sit on desk at work.

I have access to a CNC mill, which means I can whip up some pretty cool stuff easily, so I am thinking of doing an open baffle design, so I can cut something out of sheet metal easily.

I would like to do it all with some speakers from partsexpress, madisound, or similar, and not be too expensive.

Does anyone know any existing projects for open baffle speakers?

I would also consider mixing open baffle with a closed section, since I know open baffle you sacrafice a lot of low end. Maybe put one of those 5" or 6.5" tang bands in it. I am not really sure how to design a speaker, so any help anyone has would be greatly appreciated!

Thanks.
Mastercoil,
You should check out this forum, all OB stuff. And lots to read other places.
http://www.audiocircle.com/circles/index.php?board=90.0
Stay away from metal. if you want something cheap and quick, just use a piece of sheetrock. You wont have the problems with vibrations/resonances whatever with sheetrock that metal would have. Metal would transmit sound and be a source, which you don't want.
Many folks have highly recommended the hawthorne SI's as being a nobrainer and sound fantastic. I am trying to decide myself. In general you really want to stay away from passive xovers though. Check out this article about biamping that will really open your eyes about this. It is a fantastic site to read: http://sound.westhost.com/bi-amp.htm
Best of luck. A little more money now and you won't end up spending more on the "upgrade path".
Cheers,
Erik
  Reply With Quote
Old 20th April 2007, 09:42 PM   #15
diyAudio Member
 
Viridian's Avatar
 
Join Date: Jan 2007
Location: Eugene, OR
Quote:
Originally posted by justpoor


Also you've mentioned using woofer with high qts - what does high qts do. Is it better for open baffle to select woofer that has high qts.
Thanks.

Do you mind if I chime in?

Yes, for open baffle it is better to use higher Qts spec drivers. I believe that Qts is basically the balance of mechanical Q and electrical Q, in other words it is the Q total. This means that a driver which has a high Qts has less damping which translates to a gentler rolloff of efficiency as you approach Fs. Better bass extension. In OB, bass is a little hard to get, so you want something that doesn't roll off sharply.

Does that help? That is what I have gleaned so far on the subject.

Sincerely,
Erik
  Reply With Quote
Old 22nd April 2007, 02:10 PM   #16
Geoff H is offline Geoff H  Australia
diyAudio Member
 
Join Date: Oct 2006
Also, on an OB, there is little point going low in FS, particularly on smaller baffles. On the small ones I have been playing with, I got more bass by pushing FR up. These are 460mm high, 300mm wide, plus short tapered wings. FS is now at 76Hz.

What happens, I think, is an increase in efficiency where the baffle can work.

There was mention of putting these on a desk. You will have problems if the desk is against a wall. OBs like to be out in the open.

Regards,
Geoff
  Reply With Quote
Old 23rd April 2007, 02:34 AM   #17
diyAudio Member
 
Join Date: Feb 2005
Location: USA
Thanks Viridian for your explanation. Sound like the Eminence Alpha 15A is the only inexpensive that have high qts and would work well with open baffle.
  Reply With Quote
Old 23rd April 2007, 04:22 AM   #18
diyAudio Member
 
Viridian's Avatar
 
Join Date: Jan 2007
Location: Eugene, OR
Don't forget to look at the Goldwood 18"s. qts of around 1.0 Available at Partsexpress.

I actually have 4 of them on their way to my door.

Woohoo!
  Reply With Quote
Old 22nd May 2007, 04:46 PM   #19
diyAudio Member
 
AdamThorne's Avatar
 
Join Date: Oct 2006
Location: Los Angeles, CA
I was doing some finishing work on regular cabinets for my TB W3-871s and so I stuck them in 2'x2' OBs and I was suprised how nice they sound for the vocal range and up.

So now I wonder about bass for them. The eminence 15" comes up often enough. I was wondering if someone could talk about filtering them, or point me to a good OB bass (not sub) beginner resource.

Thx!
  Reply With Quote
Old 23rd May 2007, 03:01 AM   #20
holdent is offline holdent  Canada
diyAudio Member
 
Join Date: Nov 2005
Location: Ontario
JustPoor
Quote:
Would you mind sharing your crossover for the Silver Iris' plus the Alphas that you are using. I am planning to do the same with passive crossovers instead of spending money for plate amps.
Sorry, I just checked this thread for the first time in a while.

I 'm running the Silver Iris fullrange (its actually a coax driver with a crossover that comes with it) and using the Alpha to augment the bass. I've rolled off the Alpha around 270 Hz using a 4.7 mH inductor (http://www.partsexpress.com/pe/pshow...number=266-924)

Unfortunately I'm still playing with baffle size and not completely happy with the lower midrange. I'm using a baffle of 18" x 37" with the drivers centered vertically (the Alpha 8" up from the bottom and the Silver Iris 24" up). The bass is excellent but the speakers must be pulled out at least 1 m from the rear wall.

After talking about passive filtering I'm now thinking that using a plate amp or an active crossover and amp is probably the best idea. It gives you much more control over the bass drivers than possible just using passive components. By the time you've purchased and tried various components you've probably spent close to what a good plate amp would cost (like this one http://www.partsexpress.com/pe/showd...number=300-804).
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
First open baffle project Moondog55 Multi-Way 18 10th August 2008 04:35 AM
Big open baffle project hugobors Multi-Way 18 18th September 2006 03:17 PM
another Open Baffle project Tomac Multi-Way 1 14th September 2006 09:11 AM
Open Baffle project with FR punk Full Range 5 18th May 2006 01:47 AM
a speaker project : open baffle then_dude Multi-Way 0 28th March 2005 05:33 PM


New To Site? Need Help?

All times are GMT. The time now is 08:15 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2