Tapped horn for TB W8-670C? - 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 31st March 2013, 03:17 PM   #1
diyAudio Member
 
Join Date: Sep 2009
Default Tapped horn for TB W8-670C?

A while ago I bought 2x Tang Band W8-670C when half price. I built a basic bass reflex cab for one, tuned to 43Hz, which has served me well (design, sim, pictures here).

I'm wondering whether I can build a tapped horn for the second driver that will play lower than my existing bass reflex design? I don't really know much about what makes a driver suitable for tapped horn loading or not, so would greatly appreciate if somebody could briefly look at the T/S values for the W8-670C & just let me know whether it is at all possible. Datasheet is here. If so then I can start learning how to use hornresp.

I realise I could just build a larger bass reflex enclosure, but I would like to keep it as small as possible - I'm thinking something like an upscaled version of volvotreter's 6.5" 30Hz tapped horn.
  Reply With Quote
Old 31st March 2013, 05:34 PM   #2
OscarS is offline OscarS  United States
diyAudio Member
 
Join Date: Jan 2011
Quote:
Originally Posted by lost eden View Post
A while ago I bought 2x Tang Band W8-670C when half price. I built a basic bass reflex cab for one, tuned to 43Hz, which has served me well (design, sim, pictures here).

I'm wondering whether I can build a tapped horn for the second driver that will play lower than my existing bass reflex design? I don't really know much about what makes a driver suitable for tapped horn loading or not, so would greatly appreciate if somebody could briefly look at the T/S values for the W8-670C & just let me know whether it is at all possible. Datasheet is here. If so then I can start learning how to use hornresp.

I realise I could just build a larger bass reflex enclosure, but I would like to keep it as small as possible - I'm thinking something like an upscaled version of volvotreter's 6.5" 30Hz tapped horn.
Do keep in mind, that nothing is free. If you keep the enclosure volume the same, you're either going to have to sacrifice low-end extension, sensitivity, or a little of both in the tapped horn. For example, if you want 30Hz extension while keeping the enclosure volume the same, sensitivity will suffer. No escaping the evil triangle.
  Reply With Quote
Old 31st March 2013, 06:17 PM   #3
diyAudio Member
 
Join Date: Sep 2009
Quote:
Originally Posted by OscarS View Post
Do keep in mind, that nothing is free. If you keep the enclosure volume the same, you're either going to have to sacrifice low-end extension, sensitivity, or a little of both in the tapped horn. For example, if you want 30Hz extension while keeping the enclosure volume the same, sensitivity will suffer. No escaping the evil triangle.
Am I right in taking from this that the volume of an enclosure defines constraints on the low-end extension & sensitivity, regardless of the enclosure design (eg bass reflex, tapped horn, scoop, hybrid-6th-order-bandpass-horn, etc.)? So a tapped horn of similar dimensions to my current bass reflex won't be able to play lower without sacrificing sensitivity?

If so I will have to consider how to accommodate a larger enclosure into a small room, perhaps something that fits under a bed or stands behind/along a desk. My current bass reflex design can't keep up with my mains as it is, so sacrificing sensitivity isn't an option.
  Reply With Quote
Old 31st March 2013, 09:00 PM   #4
OscarS is offline OscarS  United States
diyAudio Member
 
Join Date: Jan 2011
That is absolutely correct. There is no free lunch. You can get 10% off your lunch, but ain't no way she's letting you get it for 50% off. Mother nature has a very clever way of hiding these kinds of manifestations of the laws of physics. Meaning that you can "nudge" things just a bit here and there that make it seem like you're eating without paying, but once you try and get greedy with things like ultra-small boxes, ultra-low extension, and massive sensitivity, you'll get called on your bluff and get busted and have to pay full price.

The the only way to "cheat" the evil triangle that is Hoffman's Iron Law (aside from doing things like corner 1/2 Pi boundary loading and things like that), is to sacrifice bandwidth to get a bump in sensitivity within a narrow band. Even then, it's not really cheating, because you're giving up something for something else.

I would venture to say, that driver would be a very good candidate for a tapped horn. Qts is low enough, Fs is just right for high-20s/low 30s primary tuning, and Vas is not too large.

Last edited by OscarS; 31st March 2013 at 09:02 PM.
  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
TB W8-1808 mltl bigdh31 Full Range 17 30th January 2013 06:20 PM
Help needed with TB w3-926sd, w8-670c osssyvan Full Range 3 12th December 2011 07:25 PM
Voigt Pipe for TB W8-1808 Godzilla Full Range 12 10th September 2010 05:24 PM
25-30hz tapped horn recommendation please... TB w8-740?? david45 Subwoofers 17 8th July 2010 12:27 AM
TB W8-704C mini Sonosub... nerd of nerds Subwoofers 14 19th March 2006 09:09 PM


New To Site? Need Help?

All times are GMT. The time now is 09:54 AM.


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