PUSH PULL18'S
Printed From: Speakerplans.com
Category: General
Forum Name: Advanced Discussion
Forum Description: Advanced discussion area for higher lifeforms
URL: https://forum.speakerplans.com/forum_posts.asp?TID=13936
Printed Date: 27 March 2026 at 3:11am
Software Version: Web Wiz Forums 12.08 - https://www.webwizforums.com
Topic: PUSH PULL18'S
Posted By: Strange Daze
Subject: PUSH PULL18'S
Date Posted: 17 January 2008 at 3:02pm
|
was just curious, as i dont know much about the theory of PushPull subs, whether they 'couple' in the same way as multiple reflex cabs... the reason i ask, is that ive been offered a few at a goo price, but im not gonna have 2 x duel 18s a side if im gonna have phase or coupling issues.....
And ideas??...
Cheers,
Chris.
ps- i did originally post this in Newbie discussion, but it wasnt replied to.
|
Replies:
Posted By: ceharden
Date Posted: 17 January 2008 at 3:19pm
|
When you say push-pull, you mean a twin 18" with one driver reversed and facing into the cab? They will perform just the same as one with the drivers facing the same way but with the added advantage of cancelling distortion due to non-symetrical motion of the cone. |
Posted By: Strange Daze
Date Posted: 17 January 2008 at 4:05pm
|
spot on... thats all i needed to know....
Cheers bro :)
|
Posted By: Robbo
Date Posted: 17 January 2008 at 4:09pm
| We have four Logic System 2x18 push/pull cabinets loaded with 1000 watt PHL drivers and we have been driving them with an Electrovoice P2000 bridged into each cabinet---they are quite compact and light boxes for a 2x18 and everyone has been gobsmacked on hearing them---just using one a side in a smaller venue can re-arrange your internal organs if you stand in front of them and if you think the Logic 2x15 push/pull is good then you want to hear these 2x18 versions. |
Posted By: speaker monkey
Date Posted: 17 January 2008 at 5:46pm
|
Ive never really looked into or done anything with push pull. I was just wanderin, surely the drivers would be out of time (not out of phase obv) because of the different positioning of the relative cones.
I can see how someone would say that the wavelengths are so big with such frequencies that it wont make a difference, but everything makes a little difference. Or does the cab compansate for this? Or do you delay one of the drivers..?
|
Posted By: HansA
Date Posted: 17 January 2008 at 6:21pm
|
I't wont matter. They are to close together in a to low frequenzy band to be noticable. The difference would be greater between two cabinets than within a push-pull setup. ------------- �*�o�O�o�*�*: HansA, The FUBAR sound technician :*�*�o�O�o�*� |
Posted By: tb_mike
Date Posted: 18 January 2008 at 1:53am
Youve got to visualise the wavelengths involved,calculate some,say 40hz and 400hz. If sources are within 1/4 of a wavelength apart, they might as well be called ' in phase' since there is no cancellations occuring.Perhaps higher up it will need to be filtered sharply to avoid any comb filtering etc. |
speaker monkey wrote:Posted By: snowflake
Date Posted: 18 January 2008 at 12:41pm
| if you are going to reverse a driver check that there is not any significant vent noise. some very good drivers have vent noise that is usually inaudible because it is contained inside the speaker chamber. |
Posted By: _djk_
Date Posted: 18 January 2008 at 1:45pm
|
http://speakerplans.com/forum/forum_posts.asp?TID=12739&KW=push%2Dpull&PN=1 - http://speakerplans.com/forum/forum_posts.asp?TID=12739&KW=push%2Dpull&PN=1 ------------- djk |
Posted By: ychole audio
Date Posted: 18 January 2008 at 11:21pm
|
Does anyone got plans for a push-pull cab,primarily for 18' drivers?Thanks.. ------------- I am ZERIEL'S dad!!! |
Posted By: _djk_
Date Posted: 19 January 2008 at 11:50am
|
Boxes have to be designed for specific drivers, some 21" drivers actually work in smaller boxes than the typical 18". ------------- djk |
Posted By: TOTALLYORANGE events
Date Posted: 19 February 2026 at 3:18pm
| Any chance you could send me pics of the internal of the logic cabs as I am trying to recreate them myself and I am having trouble finding a plan hopefully you can help 🤞🏻 |
Posted By: DJ-Versatile
Date Posted: 27 February 2026 at 8:43am
There's a pair for sale on FB Marketplace at the moment loaded with eminience omega drivers I think, the guy selling them always has stuff for sale and may take a deal on them unloaded if you're only interested in the cabs ------------- If you are the smartest person in the room, you're in the wrong room.... |
Posted By: TOTALLYORANGE events
Date Posted: 04 March 2026 at 7:45pm
| nice one bro for the tip👊🏻💯 |
Posted By: Plaguesguitarist
Date Posted: 05 March 2026 at 2:33pm
That'll be Reece Gilligan in Blackpool I've got a set of plans (the original tech specs/drawings) from Logic - I just need to figure out how to upload them here or if you have access to Facebook, Look on the Logic Systems owners site - they're on there Paul ------------- Why did the lampy cross the road? To steal MY sharpie. |
Posted By: BJtheDJ
Date Posted: 05 March 2026 at 4:02pm
You can attach a pic by clicking on the 'tree' icon wich is right above the letter B icon at the top of the message box. You can either post it to this site or use an external site Not sure if it'il accept anything other than JPEG. ------------- I started out in this business with nothing. I still have most of it left. |
Posted By: midas
Date Posted: 06 March 2026 at 5:38pm
|
I think some of the nicest sounding cheap sub boxes are the logic systems push pull. I think Robbo had a small ones, I had a pair of the sb2000 tall ones. Tops were Nexo msiv just one of each a side sounded lovely. Could cover a good size crowd. ------------- In bass no one can hear you scream! |
Posted By: TOTALLYORANGE events
Date Posted: 07 March 2026 at 5:13pm
| I am starting on the twin 18s this coming week the only thing about the build I was struggling with was the baffles and the support structure for the baffles thank you all for your help 👊🏻☮️💯 |