BSC for Bib?

gnugear · 29th May 2008, 10:33 PM

I know that Bibs are meant for corner placement, but I like them pulled away from the back wall because the image depth is better. I'm thinking of adding a BSC between my amp and preamp as described in this bottlehead thread:

http://www.audioasylum.com/cgi/t.mpl...ehead&m=102309

They say to use a .033uf cap for baffles 8-9" wide. My Lowther Bibs are 11.75" wide. Does anyone know what value will work for that (I can't find any info other than "larger").

GM · 30th May 2008, 12:54 AM

Assuming you haven't stuffed them to the point of 'killing' just about all its gain BW, its baffle width will be pretty much irrelevant since even away from the corners they should have enough gain to lower the baffle step considerably, so get a cheap 25 ohm pot from RS/whoever and some cheap small value caps and begin experimenting. Once dialed in, use a VOM to measure the pot's resistance and get some decent quality components to make the R/C filter.

GM

gmilitano · 30th May 2008, 03:33 AM

Here is a quick online Baffle Step Compensation / Correction Circuit Calculator you can use. It follows Martin King's paper:

http://www.quarter-wave.com/General/BSC_Sizing.pdf

gnugear · 30th May 2008, 02:40 PM

Results so far are very positive! There used to be a leaness to the sound (due to ripple?) that now sounds full and "correct" for lack of better words.

Scottmoose · 30th May 2008, 02:45 PM

Ripple is ripple, not leanness. Sounds like you've over-damped them if they don't have enough LF gain as-is.

29th May 2008, 10:33 PM	#1
gnugear diyAudio Member Join Date: Aug 2005	BSC for Bib? I know that Bibs are meant for corner placement, but I like them pulled away from the back wall because the image depth is better. I'm thinking of adding a BSC between my amp and preamp as described in this bottlehead thread: http://www.audioasylum.com/cgi/t.mpl...ehead&m=102309 They say to use a .033uf cap for baffles 8-9" wide. My Lowther Bibs are 11.75" wide. Does anyone know what value will work for that (I can't find any info other than "larger").

30th May 2008, 12:54 AM	#2
GM diyAudio Member Join Date: Jun 2003 Location: Chamblee, Ga.	Assuming you haven't stuffed them to the point of 'killing' just about all its gain BW, its baffle width will be pretty much irrelevant since even away from the corners they should have enough gain to lower the baffle step considerably, so get a cheap 25 ohm pot from RS/whoever and some cheap small value caps and begin experimenting. Once dialed in, use a VOM to measure the pot's resistance and get some decent quality components to make the R/C filter. GM __________________ Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.

30th May 2008, 03:33 AM	#3
gmilitano diyAudio Member Join Date: Apr 2004 Location: Winnipeg, Manitoba	Here is a quick online Baffle Step Compensation / Correction Circuit Calculator you can use. It follows Martin King's paper: http://www.quarter-wave.com/General/BSC_Sizing.pdf __________________ DIY Audio Projects [ 10" DIY Subwoofer \| FE127E Sealed Bipole \| [ LM3886 Chip Amp / Gainclone \| K-12M Tube Amp Kit ]

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	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

30th May 2008, 02:40 PM	#4
gnugear diyAudio Member Join Date: Aug 2005	Results so far are very positive! There used to be a leaness to the sound (due to ripple?) that now sounds full and "correct" for lack of better words.

30th May 2008, 02:45 PM	#5
Scottmoose diyAudio Member Join Date: Mar 2005 Location: UK	Ripple is ripple, not leanness. Sounds like you've over-damped them if they don't have enough LF gain as-is.