Making ELF/EAS work lower

Nuuk · 26th March 2007, 12:50 PM

By lower, I don't mean the bottom end but the top end. I want to build an ELF/EAS sub that would match up with my OB woofers that go down to around 27hz.

I've read Rod Elliot's article several times but still don't understand how to achieve what I want. Any advice please?

richie00boy · 26th March 2007, 01:04 PM

This is one of the things I dislike about EAS, you have to change the box size to change the crossover frequency. Increasing size lowers the frequency.

Nuuk · 26th March 2007, 01:06 PM

Call me psychic Richie but I just knew you were going to reply!

So I would have to make a bigger box to get lower which sort of removes the advantage of the ELF design. Oh well, back to the drawing board as they.

richie00boy · 26th March 2007, 01:40 PM

Or you could use a Linkwitz Transform and low-pass filter...

phase_accurate · 26th March 2007, 02:18 PM

Or you can add two resitors to the ELF and a lowpass.

Regards

Charles

Nuuk · 26th March 2007, 03:33 PM

Thanks Charles.

Just to clarify, do you mean that by adding the two resistors, I can make the lp filte? Or that I must make an lp filter and then add two resistors? If the latter where do I add the resistors?

richie00boy · 26th March 2007, 03:39 PM

I was tryng to work out what he meant. I think he means add resistors to the integrators (in series with the existing caps) to give a shelving action at the present crossover frequency, then add a low-pass filter.

pinkmouse · 26th March 2007, 03:41 PM

I'd just build a low pass feeding a LT personally.

What's the in room roll off of the OBs?

phase_accurate · 26th March 2007, 03:42 PM

Quote:

I was tryng to work out what he meant. I think he means add resistors to the integrators (in series with the existing caps) to give a shelving action at the present crossover frequency, then add a low-pass filter.

The candidate has 100 Points !

Regards

Charles

Nuuk · 26th March 2007, 03:53 PM

Quote:

I'd just build a low pass feeding a LT personally.

It LT is actually TL then that won't be small PM!

Quote:

What's the in room roll off of the OBs?

I haven't actually measured it but I would guess around 27-30 hz.

26th March 2007, 12:50 PM	#1
Nuuk diyAudio Member Join Date: Feb 2003 Location: Somerset, SW England	Making ELF/EAS work lower By lower, I don't mean the bottom end but the top end. I want to build an ELF/EAS sub that would match up with my OB woofers that go down to around 27hz. I've read Rod Elliot's article several times but still don't understand how to achieve what I want. Any advice please? __________________ The truth need not be veiled, for it veils itself from the eyes of the ignorant.

26th March 2007, 01:04 PM	#2
richie00boy Did it Himself diyAudio Member Join Date: Nov 2003 Location: Gloucestershire, England, UK	This is one of the things I dislike about EAS, you have to change the box size to change the crossover frequency. Increasing size lowers the frequency. __________________ www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more

26th March 2007, 01:06 PM	#3
Nuuk diyAudio Member Join Date: Feb 2003 Location: Somerset, SW England	Call me psychic Richie but I just knew you were going to reply! So I would have to make a bigger box to get lower which sort of removes the advantage of the ELF design. Oh well, back to the drawing board as they. __________________ The truth need not be veiled, for it veils itself from the eyes of the ignorant.

26th March 2007, 01:40 PM	#4
richie00boy Did it Himself diyAudio Member Join Date: Nov 2003 Location: Gloucestershire, England, UK	Or you could use a Linkwitz Transform and low-pass filter... __________________ www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more

26th March 2007, 03:33 PM	#6
Nuuk diyAudio Member Join Date: Feb 2003 Location: Somerset, SW England	Thanks Charles. Just to clarify, do you mean that by adding the two resistors, I can make the lp filte? Or that I must make an lp filter and then add two resistors? If the latter where do I add the resistors? __________________ The truth need not be veiled, for it veils itself from the eyes of the ignorant.


	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

26th March 2007, 02:18 PM	#5
phase_accurate diyAudio Member Join Date: May 2002 Location: Switzerland	Or you can add two resitors to the ELF and a lowpass. Regards Charles

26th March 2007, 03:39 PM	#7
richie00boy Did it Himself diyAudio Member Join Date: Nov 2003 Location: Gloucestershire, England, UK	I was tryng to work out what he meant. I think he means add resistors to the integrators (in series with the existing caps) to give a shelving action at the present crossover frequency, then add a low-pass filter. __________________ www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more

26th March 2007, 03:41 PM	#8
pinkmouse diyAudio Moderator Join Date: Apr 2002 Location: Chatham, England	I'd just build a low pass feeding a LT personally. What's the in room roll off of the OBs? __________________ Al I conceive of nothing, in religion, science or philosophy, that is more than the proper thing to wear, for a while. Charles Fort

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

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Lower rails for lower impedance?	95Honda	Solid State	7	19th December 2007 08:59 AM
DDE V1.1, how to lower output	ar1617	Digital Source	2	7th November 2006 10:56 AM
L-Lower?	oliverh	Pass Labs	12	23rd August 2006 04:25 PM
Making Two Speakers Work Together	MuaDibb	Multi-Way	5	29th April 2006 02:16 PM
Zen with lower voltage?	DorcyDuck	Pass Labs	9	20th April 2004 05:02 PM

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