LISTSERV mailing list manager LISTSERV 16.5

Help for CSOUND Archives


CSOUND Archives

CSOUND Archives


CSOUND@LISTSERV.HEANET.IE


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Monospaced Font

LISTSERV Archives

LISTSERV Archives

CSOUND Home

CSOUND Home

CSOUND  March 2016

CSOUND March 2016

Subject:

Re: Crossover filters

From:

Peter Burgess <[log in to unmask]>

Reply-To:

A discussion list for users of Csound <[log in to unmask]>

Date:

Fri, 4 Mar 2016 14:30:16 +0000

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (217 lines)

Anyone have any ideas on this?

Basically I just need to know, is it generally acceptable to just live
with a bit of a peak in the crossover points, or should I aim for a
near flat response all round?

Are there any better filters for the job, or any tricks (like simply
using a limiter) that will help me overcome?

Pete

On Wed, Mar 2, 2016 at 4:04 PM, Peter Burgess
<[log in to unmask]> wrote:
> I've done some 2 band crossover tests using these two butterworth
> filter configurations:
>
> icrossfreq = 60
>
> ; Crossover Test 1 (butxp opcodes)
> alowsig1 butlp gacompsig, icrossfreq
> alowsig2 butlp alowsig1, icrossfreq
> ahisig1 buthp gacompsig, icrossfreq
> ahisig2 buthp ahisig1, icrossfreq
> out alowsig2 + ahisig2
>
> ; Crossover Test 2 (clfilt opcode)
> inpol init 4
> alowsig clfilt gacompsig, icrossfreq, 0, inpol
> ahisig clfilt gacompsig, icrossfreq, 1, inpol
> out alowsig + ahisig
>
> I have tested these two crossovers with a rich kick sound, and with
> pink noise, using various different crossover frequencies. When
> watching the amplitudes in the terminal, it would appear that both
> crossover setups produce an output with a higher peak somewhere,
> compared to the unaffected sound.
>
> For the kick, the unaltered sound has an amplitude of 0.49851.
> With a crossover frequency of 60, Test 1 produces amplitudes of
> between 0.72 and 0.86, while Test 2 produces amplitudes of between
> 0.75 and 0.94.
>
> I couldn't hear a great deal of audible difference between the three,
> so I spectrum analysed some samples. I have attached these spectrums,
> as well as the audio samples.
>
> The spectrum analysis shows a slight difference near the crossover
> point for Test 1, but a much more noticeable difference around the
> crossover for Test 2.
>
> I am drawing the conclusion that Test 1's crossover is better, but are
> there filters that will do even better still? Is it possible or easy
> to get a totally level crossover? Or could I just limit the output of
> the crossovers to the original signals level?
>
> On Wed, Mar 2, 2016 at 12:58 AM, Peter Burgess
> <[log in to unmask]> wrote:
>> Ah hang on, a further read about crossovers says that the most
>> commonly used filters are 4th order Linkwitz–Riley filters, which
>> apparently just use two cascaded 2nd order butterworth filter.... I'm
>> no DSP expert, but doesn't that just make it a 4th order butterworth?
>>
>> On Tue, Mar 1, 2016 at 11:36 PM, Peter Burgess
>> <[log in to unmask]> wrote:
>>> That's fine, and is what I was intending, but does Csound have a
>>> suitable filter for a crossover? As I have read and now also tested,
>>> the butterworth isn't suitable
>>>
>>> On Tue, Mar 1, 2016 at 11:30 PM, Rory Walsh <[log in to unmask]> wrote:
>>>> A suite of mastering UDOs would be a good start. Gleb proposed such a thing
>>>> some time back, but I don't think much came of it.
>>>>
>>>> On 1 March 2016 at 23:28, Dr. Richard Boulanger <[log in to unmask]>
>>>> wrote:
>>>>>
>>>>> For sure Rory,
>>>>>
>>>>> That is what we do; but Csound could really use some "mastering" opcodes
>>>>> not just "mastering instruments" Dr.B.
>>>>> _____________________________________________
>>>>> On Tue, Mar 1, 2016 at 6:14 PM, Rory Walsh <[log in to unmask]> wrote:
>>>>>>
>>>>>> Why not just use the opcodes we have to create one?
>>>>>>
>>>>>> On 1 Mar 2016 21:35, "Peter Burgess" <[log in to unmask]>
>>>>>> wrote:
>>>>>>>
>>>>>>> I was thinking that too, and a big part of me wants to try and write
>>>>>>> one, but I've already started 3 opcodes and never found the time to
>>>>>>> finish any of them, so I should probably stop kidding myself that I'm
>>>>>>> gonna get round to something like that in the near future, haha! :D
>>>>>>>
>>>>>>> On Tue, Mar 1, 2016 at 8:50 PM, Dr. Richard Boulanger
>>>>>>> <[log in to unmask]> wrote:
>>>>>>> > We could really use a multi-band compressor opcode!
>>>>>>> >
>>>>>>> > -dB
>>>>>>> >
>>>>>>> > _____________________________________________
>>>>>>> > Dr. Richard Boulanger
>>>>>>> > Professor of Electronic Production and Design
>>>>>>> > Professional Writing and Music Technology Division
>>>>>>> > Berklee College of Music
>>>>>>> > 1140 Boylston Street, FB-75
>>>>>>> > Boston, MA 02215-3693
>>>>>>> > Office @ 161 Mass Ave - 4th Floor
>>>>>>> > 617-747-2384 (office) 774-488-9166 (cell)
>>>>>>> > ______________________________________________
>>>>>>> > [log in to unmask] (email)
>>>>>>> > https://www.facebook.com/richard.boulanger.58 (facebook)
>>>>>>> > ______________________________________________
>>>>>>> > President of Boulanger Labs - http://boulangerlabs.com
>>>>>>> > Director of Csounds.com - http://csounds.com
>>>>>>> > Author & Editor: The Csound Book -
>>>>>>> > http://mitpress.mit.edu/books/csound-book
>>>>>>> > Author & Editor: The Audio Programming Book -
>>>>>>> > http://mitpress.mit.edu/books/audio-programming-book
>>>>>>> > ______________________________________________
>>>>>>> > about: http://www.boulangerlabs.com/about/richardboulanger/
>>>>>>> > about:
>>>>>>> > http://www.csounds.com/community/developers/dr-richard-boulanger/
>>>>>>> > ______________________________________________
>>>>>>> > music:
>>>>>>> >
>>>>>>> > http://www.csounds.com/community/developers/dr-richard-boulanger/dr-richard-boulanger-music/
>>>>>>> >
>>>>>>> > On Tue, Mar 1, 2016 at 3:15 PM, Peter Burgess
>>>>>>> > <[log in to unmask]> wrote:
>>>>>>> >>
>>>>>>> >> Hi there, I'm planning to knock up a multi-band compressor, and I was
>>>>>>> >> wondering if csound has any filters built for this job? My first
>>>>>>> >> thought was to use butterworths, but I've just read that the combined
>>>>>>> >> signal has a slight peak at the crossover point. Apparently
>>>>>>> >> Linkwitz-Riley filters are better for the job. Do we have anything
>>>>>>> >> like that?
>>>>>>> >>
>>>>>>> >> Pete
>>>>>>> >>
>>>>>>> >> --
>>>>>>> >> http://algorythmradio.com
>>>>>>> >> https://soundcloud.com/algorythmradio
>>>>>>> >>
>>>>>>> >> Csound mailing list
>>>>>>> >> [log in to unmask]
>>>>>>> >> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
>>>>>>> >> Send bugs reports to
>>>>>>> >> https://github.com/csound/csound/issues
>>>>>>> >> Discussions of bugs and features can be posted here
>>>>>>> >
>>>>>>> >
>>>>>>> > Csound mailing list [log in to unmask]
>>>>>>> > https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to
>>>>>>> > https://github.com/csound/csound/issues Discussions of bugs and
>>>>>>> > features can
>>>>>>> > be posted here
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> http://algorythmradio.com
>>>>>>> https://soundcloud.com/algorythmradio
>>>>>>>
>>>>>>> Csound mailing list
>>>>>>> [log in to unmask]
>>>>>>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
>>>>>>> Send bugs reports to
>>>>>>> https://github.com/csound/csound/issues
>>>>>>> Discussions of bugs and features can be posted here
>>>>>>
>>>>>> Csound mailing list [log in to unmask]
>>>>>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to
>>>>>> https://github.com/csound/csound/issues Discussions of bugs and features can
>>>>>> be posted here
>>>>>
>>>>>
>>>>> Csound mailing list [log in to unmask]
>>>>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to
>>>>> https://github.com/csound/csound/issues Discussions of bugs and features can
>>>>> be posted here
>>>>
>>>>
>>>> Csound mailing list [log in to unmask]
>>>> https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to
>>>> https://github.com/csound/csound/issues Discussions of bugs and features can
>>>> be posted here
>>>
>>>
>>>
>>> --
>>> http://algorythmradio.com
>>> https://soundcloud.com/algorythmradio
>>
>>
>>
>> --
>> http://algorythmradio.com
>> https://soundcloud.com/algorythmradio
>
>
>
> --
> http://algorythmradio.com
> https://soundcloud.com/algorythmradio



--
http://algorythmradio.com
https://soundcloud.com/algorythmradio

Csound mailing list
[log in to unmask]
https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND
Send bugs reports to
        https://github.com/csound/csound/issues
Discussions of bugs and features can be posted here

Top of Message | Previous Page | Permalink

Advanced Options


Options

Log In

Log In

Get Password

Get Password


Search Archives

Search Archives


Subscribe or Unsubscribe

Subscribe or Unsubscribe


Archives

March 2019
February 2019
January 2019
December 2018
November 2018
October 2018
September 2018
August 2018
July 2018
June 2018
May 2018
April 2018
March 2018
February 2018
January 2018
December 2017
November 2017
October 2017
September 2017
August 2017
July 2017
June 2017
May 2017
April 2017
March 2017
February 2017
January 2017
December 2016
November 2016
October 2016
September 2016
August 2016
July 2016
June 2016
May 2016
April 2016
March 2016
February 2016
January 2016
December 2015
November 2015
October 2015

ATOM RSS1 RSS2



LISTSERV.HEANET.IE

Secured by F-Secure Anti-Virus CataList Email List Search Powered by the LISTSERV Email List Manager