Tang Band W5-704 and a TB ceramic tweeter - Page 2 - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

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 23rd September 2012, 10:31 PM   #11
imagios is offline imagios  Czech Republic
diyAudio Member
 
Join Date: Oct 2009
Location: prague
Hi Sreten,
thanks for the hint, indeed the 20l are really more than 2x the Vas, according to wolf_teeth´s measurements one driver had a Vas of cca 8,5 the second of 9,7, that would give a average of 18,2liter as a max.
Less than 20, but in about less than a 10% tolerance, how exact is this rule? Would it now work anyway? (I still try to understand this rule, I dont know exactly yet what would that mean soundvise ...)
I tried in WinISD the 12l box and to turn it down to 40hz is quite a magic, what is your size of the port, to keep the air still moving at decent speet at f.e. 10watts?
  Reply With Quote
Old 23rd September 2012, 11:10 PM   #12
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

1.4" internal diameter x 5" length should work well for 12L.

The average is 9.1L not 18.2L, a little lower than Zaphs.

rgds, sreten.
__________________
There is nothing so practical as a really good theory - Ludwig Boltzmann
When your only tool is a hammer, every problem looks like a nail - Abraham Maslow
  Reply With Quote
Old 24th September 2012, 07:23 AM   #13
imagios is offline imagios  Czech Republic
diyAudio Member
 
Join Date: Oct 2009
Location: prague
Quote:
Originally Posted by sreten View Post
The average is 9.1L not 18.2L, a little lower than Zaphs.

rgds, sreten.
Yes, I mend the maximum for the average would be 2x9.1=18.2l

I will recalculate the size of the 12l box and put that into sketchup to see how the 5" port would fit, I place it later here.
WinISD gives me on your values a -3db at 80hz and a - 8db at 37,3hz

Last edited by imagios; 24th September 2012 at 07:26 AM.
  Reply With Quote
Old 24th September 2012, 09:52 AM   #14
Allstar is offline Allstar  United Kingdom
diyAudio Member
 
Join Date: Aug 2010
Location: U.K.
Quote:
Originally Posted by sreten View Post
Hi,

According to Zaph|Audio We have 12.1L Vas, 53Hz Fs and 0.49 Qts for the W5.

According to my WinISD modelling about 12L tuned to 40Hz should work well. 20L is
large for a 5", and you really don't want Vbox to be greater than Vas in nearly all cases.

rgds, sreten.
I'm in the process of building something very similar to imagios' initial 20 liter plan using the W5 704D driver.
Mine is a tad smaller at 19 liters using similar tall, deep and slim box dimensions with the port tuning at 41Hz.

What are the consequences of box volume exceeding Vas ? Is it a case of increased excursion due to less restoring force from the box ?
  Reply With Quote
Old 24th September 2012, 10:09 AM   #15
imagios is offline imagios  Czech Republic
diyAudio Member
 
Join Date: Oct 2009
Location: prague
just for update, here is what WinISD gave me on Srtens values, and here is the 3D model of the inner volume for such a box...
Click the image to open in full size.
Click the image to open in full size.
  Reply With Quote
Old 24th September 2012, 08:27 PM   #16
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

Using Zaphs parameters and a 12L box tuned to 40Hz I get :
-3dB at 56Hz, -6dB at 42Hz, and -10dB at 32Hz. Basically
good bass down to 40Hz with a quasi 1st order shape.
Mild 0.3dB peak 100Hz to 200Hz. (WinISD 0.44)

Somewhat better than a 12L Qbox=0.69 sealed box.
(-3dB at 77Hz, -6dB at 58Hz, and -10dB at 44Hz).

rgds, sreten.

The bigger the box the more it is susceptible to driver vagaries.
If Vbox exceeds Vas then simply put you would be better off
with a bigger driver, many 6.5"ers work very well in around 20L.

Vas to Vbox ratio determines how much the box air linearises
the drivers suspension, the smaller the box the more linear.
__________________
There is nothing so practical as a really good theory - Ludwig Boltzmann
When your only tool is a hammer, every problem looks like a nail - Abraham Maslow

Last edited by sreten; 24th September 2012 at 08:33 PM.
  Reply With Quote
Old 24th September 2012, 08:41 PM   #17
imagios is offline imagios  Czech Republic
diyAudio Member
 
Join Date: Oct 2009
Location: prague
Thanks Sreten for clarifying,
I might just out of curiosity get some cheap wood and build one testing box in 20l and one for the 12l, no crossover and only the 5" driver just to test the sound difference...
I dont get it why in that case TB says the driver works well in a 20l box...
  Reply With Quote
Old 24th September 2012, 09:33 PM   #18
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

With Zaphs specs the classic maximally flat vented alignment comes
out as 23L tuned to 44Hz. Flat to 50Hz, -3dB at 40Hz and around
the same -10dB point as the 12L tuned to 40Hz.

Problem is in a real room you'll end up with the classical vented boomy
bass problem, poor transient response, and nearly certain one note bass.
The box will not appreciably linearise driver distortion.

Which isn't a good return for building twice as big boxes. My simple
modelling indicates 15L tuned to 38Hz is about as good as it gets
for this driver, and 15L is plently enough for many 6.5" drivers.

So an intelligent use is around 5-10L sealed and little more vented.

rgds, sreten.
__________________
There is nothing so practical as a really good theory - Ludwig Boltzmann
When your only tool is a hammer, every problem looks like a nail - Abraham Maslow

Last edited by sreten; 24th September 2012 at 10:02 PM.
  Reply With Quote
Old 24th September 2012, 09:58 PM   #19
imagios is offline imagios  Czech Republic
diyAudio Member
 
Join Date: Oct 2009
Location: prague
Ok that would bring me to Michaels size with his 13 liters on his Oriole project...
I had my doubts when I saw the Qts of the driver, whether he really fits a vented box... it seems he might do a better job in a three way system sealed and high-passed from 110hz, but I definitely go for the two way with the ceramic tweeter. (as both where a birthday gift )
I seems I can not get a low frequency and nice sound, you just cant argue with the physics ...
  Reply With Quote
Old 25th September 2012, 08:03 AM   #20
Allstar is offline Allstar  United Kingdom
diyAudio Member
 
Join Date: Aug 2010
Location: U.K.
It seems my 19 litre box will be on the large side for the W5 704D, but I am well on the way to completing the enclosures so I think I will carry on and hear what happens. Though it'll be some weeks before I complete everything I shall certainly post my results back here. Looking forward to seeing where your design heads too Imagios, please keep us updated.

By the way, thanks for you comments about the effects of box size Sreten. It cause a few stuck pennies to drop.
  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
Tang Band W5-1880 briandk Full Range 16 1st November 2012 08:45 PM
Tang Band W8-1808 / TB ribbon tweeter / Eminence Alpha 15A in OB with U-frame superlian Full Range 3 3rd September 2011 11:11 PM
Tang Band W5-1685 BIB? geepee Full Range 5 16th August 2010 12:00 AM
Tang Band W5-704D revelator Full Range 0 1st February 2008 06:26 AM
Tang Band w5-704s MITMechE Multi-Way 8 26th February 2007 02:38 PM


New To Site? Need Help?

All times are GMT. The time now is 06:28 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