X-tro Question
Printed From: Speakerplans.com
Category: Plans
Forum Name: Punisher and X-tro
Forum Description: Discussion / Questions about the Punisher and X-tro
URL: https://forum.speakerplans.com/forum_posts.asp?TID=22442
Printed Date: 27 March 2026 at 9:30am
Software Version: Web Wiz Forums 12.08 - https://www.webwizforums.com
Topic: X-tro Question
Posted By: AndrAAx
Subject: X-tro Question
Date Posted: 31 December 2008 at 10:21am
|
Been looking at the drawings for these ones, and found a think that felt abit strange!
In the pictures theres a big chamber in the horn part between the upper and lower 15" driver!
The question!
Why isnt this room used as box volume for the rear chamber?
The lower chamber i can understand , it isnt that much room!
Im not good at horn designs, but mabey you can get it to go a bit lower? Or?  ------------- It’s hard to make a thing idiot-proof! Because idiots are so bloody genius! |
Replies:
Posted By: tb_mike
Date Posted: 02 January 2009 at 12:30am
|
My guess is that if it wasnt used,the driver doesnt require a chamber that large. The rear chamber is an air cushion which makes the biggest difference below cutoff,reducing excursion greatly. The front chamber,and horn path length determines cutoff. |
Posted By: darkmatter
Date Posted: 02 January 2009 at 2:36pm
| In the xtro the 15" drivers fire parallel and are about the same distance from the horn mouth. I can't think of an alternative folding that would maintain this quality and still make use of the unused space you're referring to, I guess this might be part of the reason. |
Posted By: AndrAAx
Date Posted: 02 January 2009 at 10:30pm
|
Its not the folding! Its the volume that chamber holds, if i open it up into the chamber thats behind the 15" drivers i can incrise the volume for those drivers! But will it do any good? And what effect will it have on the overall? ------------- It’s hard to make a thing idiot-proof! Because idiots are so bloody genius! |
Posted By: darkmatter
Date Posted: 03 January 2009 at 1:01pm
| What Mike's said - if you wanted the lf extension you'd need a longer horn and larger mouth. Increasing rear chamber size isn't necessary as far as I know, you'll just weaken the baffle board. |
Posted By: Sibulus
Date Posted: 04 February 2009 at 4:58pm
| I don't think they need to drop any lower, not considering their application: i.e ontop of something else |
Posted By: Peter Jan
Date Posted: 08 February 2009 at 11:18am
Such small and short horns like X-Tro, HD15, etc... are not real horns. They are a closed box design with horn assistance you might say. Or it's not wrong to say it acts as a bandpass enclosure either, the horn works as a tapered port. Designing from the bandpass route or closed box with-horn-assist will give very similar results. Anyway, the reason it won't do any good to open up the rear chambers, is that the working ( the tuning ) of either bandpass or the closed box is dependant of many parameters and volume is one of those parameters. If you change that parameter, the whole systems response will change with it, with undesirable effects like boomy or thin sound, less power capability, faster reached X-max among others. If you want or need something that starts lower than 90Hz with the same SPL below as above 90Hz, than the X-Tro is not for you. It's form and dimensions were intended to use from 90Hz and up and work very strong from that point. Lower cut off needs will dictate the use of other ( and bigger ) cabinets, an other design, with a longer hornpath to begin with. All parameters of speaker and cabinet are interacting in a balanced system, changing one parameter without changing the others accordingly, will never give good results. |
AndrAAx wrote: