PLL notch filter for Neo3 PDR open baffled?

0 Members and 1 Guest are viewing this topic. Read 2365 times.

SAC

PLL notch filter for Neo3 PDR open baffled?
« on: 27 Dec 2009, 05:46 pm »
Has anyone done a PLL notch filter for the Neo3 PDR run open-baffled? 

Can someone direct me to a calculator somewhere to do this?  I already have an excel spreadsheet for doing PLL crossovers thanks.

Thanks
Sean
« Last Edit: 7 Jan 2010, 01:48 pm by SAC »

Davey

  • Full Member
  • Posts: 1481
Re: PLL notch filter for Neo3 PDR open baffled!
« Reply #1 on: 27 Dec 2009, 09:59 pm »
Figure A.

http://www.linkwitzlab.com/filters.htm#7

You're going to find that a suitable inductor is probably a very high value.  Probably better to implement a notch filter of this type with an active inductor.  Or just do it at speaker level.

Cheers,

Dave.

SAC

Re: PLL notch filter for Neo3 PDR open baffled!
« Reply #2 on: 28 Dec 2009, 12:45 am »
By PLL I mean passive line-level.  In fact I already have a notch filter with a capacitor and a resistor in place but I copied it from a design for the B200 peak at 7khz.  I would like something tailored for the Neo3.

Come to think of it, I am not sure if I have implemented the notch filter correctly since I transferred it from a circuit elsewhere into my own 6db hP crossover.  There was a resistor in line with the driver in the initial circuit that I did not think to remove. 

I cannot get into the Linkwitz webpages at the moment  :(  Perhaps I will learn the answer there.  I'll try again later.


Davey

  • Full Member
  • Posts: 1481
Re: PLL notch filter for Neo3 PDR open baffled!
« Reply #3 on: 28 Dec 2009, 03:54 am »
Yep, the link is for a passive-line-level notch filter.

If your existing filter is just a capacitor and resistor(s) then you don't have a notch filter.  It will be some sort of shelving filter depending upon the configuration.

Cheers,

Dave.

SAC

Re: PLL notch filter for Neo3 PDR open baffled!
« Reply #4 on: 7 Jan 2010, 01:46 pm »
Thanks Dave

It's making sense to me now.  I did indeed copy a shelving filter when I wanted a notch filter.  Maybe I will settle for a shelving filter, unless someone can recommend some specific values they used in their own implementations with the neo3 open baffled.

I still cannot get into the Linkwitz website.  I got on it a week or two ago just once but every other time the pages will not load  :(  Maybe the website is down!?  Is there anywhere else I can get that info, anyone?