Peerless Isobarik - diyAudio
Go Back   Home > Forums > Loudspeakers > Subwoofers

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 2nd November 2003, 02:05 PM   #1
hifidan is offline hifidan  Canada
diyAudio Member
 
Join Date: Aug 2003
Location: Canada
Thumbs up Peerless Isobarik

these are my 2 subs finally finished. I have 2 Isobarik boxes (75 liters) using 2 Peerless 831727 each, tuned with a 4 inch port 38 inches long, tuned to 22 Hz. These are very musical subs, not boomy. the box is 1 inch MDF all around . Total weight is 75 pounds each. I also built an small 1 cu foot sealed box with an Peerless 10 inch 269 and its passive radiator. This one doesn't get as down as the Iso (-3 at 30Hz) but it makes up in total output. Really good for H/T, very quiet motor
Attached Images
File Type: jpg sub 008.jpg (86.9 KB, 854 views)
__________________
HifiDan
  Reply With Quote
Old 2nd November 2003, 04:01 PM   #2
Rarkov is offline Rarkov  England
diyAudio Member
 
Rarkov's Avatar
 
Join Date: Aug 2002
Location: North East, UK
Send a message via ICQ to Rarkov Send a message via Skype™ to Rarkov
Well done! Sounds like an interesting configuration.

Gaz
  Reply With Quote
Old 2nd November 2003, 05:21 PM   #3
Bull is offline Bull  United Kingdom
diyAudio Member
 
Join Date: Oct 2002
Location: ...........
Question reply

Isn't Isobarik the same as push-pull subs?
  Reply With Quote
Old 2nd November 2003, 05:53 PM   #4
Guss is offline Guss  Canada
diyAudio Member
 
Guss's Avatar
 
Join Date: Jun 2003
Location: Montreal
Push-pull, two woofer sharing the same enclosure with one driver's magnet firing out of the sub so both cones move together.

Isobarik is used as a piston to reduce the size of the sub.
  Reply With Quote
Old 2nd November 2003, 11:43 PM   #5
hifidan is offline hifidan  Canada
diyAudio Member
 
Join Date: Aug 2003
Location: Canada
I first built them with a single hp and I got very good response.
Adding the second woofer in Iso config, changed everything. The bass just tightened a whole lot. Boomy bass just dissapeared. Adding the seconf woofer did not really improved on dynamics. I still could bottom the speakers on h/t,(That's the reason I built the small 269 Peerless). What it did is change the whole speaker response, I guess it is true that all the distorsion is cancelled in the process. If you can, add that in your design, you wont be sorry.
Happy listening
__________________
HifiDan
  Reply With Quote
Old 3rd November 2003, 07:48 AM   #6
Rarkov is offline Rarkov  England
diyAudio Member
 
Rarkov's Avatar
 
Join Date: Aug 2002
Location: North East, UK
Send a message via ICQ to Rarkov Send a message via Skype™ to Rarkov
I do like the speakers in the background! Is that a focal tweeter? If so - how much and from where?! Are they DIY?

More info thanx!

Gaz
  Reply With Quote
Old 3rd November 2003, 12:39 PM   #7
hifidan is offline hifidan  Canada
diyAudio Member
 
Join Date: Aug 2003
Location: Canada
Yes, they are the JM Lab Electra 905, the model just before they changed to the 906, not DIY thou. I have added a ring around the tweeter, made of mousse to improve their imaging.
Cheers
__________________
HifiDan
  Reply With Quote
Old 5th November 2003, 01:37 PM   #8
Vince35 is offline Vince35  France
diyAudio Member
 
Vince35's Avatar
 
Join Date: Nov 2003
Location: (35) near Rennes
Send a message via MSN to Vince35
Hello ! My first reply on this great DIY forum...
Quote:
I have added a ring around the tweeter, made of mousse to improve their imaging.
I made it too around Focal TC 120 TD5, that's very beneficial : I removed a little peak in the frequency response at about 3 kHz and the imaging has been improved too.
Here is what it looks like :
http://www.homecinema-fr.com/forum/download.php?id=1141


Vincent
__________________
Sorry if my english is bad...
  Reply With Quote
Old 9th November 2003, 10:16 AM   #9
diyAudio Member
 
Join Date: Mar 2003
Location: brisbane queensland
I am at the moment making a similar sub using 2 of the 831875 12" classic series drivers in a 60 ltr box .

could you tell me how far apart you have the drivers .

did you just guess how much you needed or is there a way to do this

Also what is the idea behind the material around the tweeter .
Are some materials better than others . Will this work on any tweeter ? thanks
  Reply With Quote
Old 9th November 2003, 12:31 PM   #10
Vince35 is offline Vince35  France
diyAudio Member
 
Vince35's Avatar
 
Join Date: Nov 2003
Location: (35) near Rennes
Send a message via MSN to Vince35
For the material around the tweeter :
I use a material which is called "thibaude de laine" in France. This is particularly effective in absorbing the mid/high (so what interest us for the tweak).
This who hifidan is using is effective too.

I'll try to explain why making this tweak...
When placing the tweeter in the medium of the baffle, some "bad" waves appear on the baffle around the tweeter, which are deterioring the imaging and can cause a little peak on the frequency response.
Another tweak really effective is not to place the tweeter on the medium of the baffle, but on a side of the baffle (prefer the right side for the left loudspeaker and conversely).

Some manufacturers are using those tweaks.


Vincent
__________________
Sorry if my english is bad...
  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
isobarik sub using peerless drivers busterno1 Subwoofers 6 18th September 2011 01:45 PM
Peerless 1727 Isobarik ? flacoman Subwoofers 1 15th May 2006 04:26 PM
Isobarik sub rathek Subwoofers 23 10th December 2004 03:58 PM


New To Site? Need Help?

All times are GMT. The time now is 12:58 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