Main Forums >> Production - Mixing, Mastering, Gear & Techniques
        Print Thread

Pages: 1
Dodger



Joined: 28/11/09
Posts: 222
Linear Phase EQ
      #812722 - 17/02/10 10:49 PM
Hi just started using logic and have noticed that the channel EQ and Linear phase EQ look exactly the same and really am just wondering....

what is a liner phase eq?

and how dose it differ from the normal EQ?

thanks Jack


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Hugh RobjohnsAdministrator
SOS Technical Editor


Joined: 25/07/03
Posts: 22279
Loc: Worcestershire
Re: Linear Phase EQ new [Re: Dodger]
      #812840 - 18/02/10 11:56 AM
A linear phase filter has constant group delay, which means that all frequency components of the signal suffer an equal delay time as they pass through the filter.

'Normal' equalisers aren't linear phase and have a group delay which varies with frequency. So some frequncies come out the far end slightly earlier or later than other frequecies. This results, inevitably in phase distortion -- but it is a distortion that we are used to and associate with recorded sound, and it is what makes different equaliser designs sound different.

hugh

--------------------
Technical Editor, Sound On Sound


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Dodger



Joined: 28/11/09
Posts: 222
Re: Linear Phase EQ new [Re: Dodger]
      #813298 - 19/02/10 09:38 PM
thanks

so what are the applications of it ?

i heard it mentioned once in a music tech lesson we didn't go into much because he said we didn't need to know it and we need to get back to learning about wherever we were doing because we had gone off on one (there are only 3 of us in the class its easy)

any back on subject he said it was very processor heavy and can cause a lot of latency on channels applied on. if the channel you put it on is going to have a lot of latency on it then surely that defeats the object of having the linear EQ in the first place?

Jack


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Dodger



Joined: 28/11/09
Posts: 222
Re: Linear Phase EQ new [Re: Dodger]
      #813310 - 19/02/10 10:21 PM
Also why am i on this little sort of rant ha ha

what is the difference between the adaptive limiter and the normal limiter?

i was recommended to use one for mastering? but i dont no why?

Thanks sorry if these questions are stupid..


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Mixedup
active member


Joined: 03/09/03
Posts: 4857
Loc: Cambridge, UK
Re: Linear Phase EQ new [Re: Dodger]
      #815907 - 02/03/10 07:58 AM
Quote Dodger:

so what are the applications of it ?




Think surgical/clinical for linear phase EQ. For non-linear phase think character. Linear phase EQs do tend to take more processing power. This SOS article might help. Also keep your eyes peeled for forthcoming Mix Rescue articles that address this issue in a practical context.


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Martin WalkerModerator
Watcher Of The Skies


Joined: 28/02/01
Posts: 17716
Loc: Cornwall, UK
Re: Linear Phase EQ new [Re: Dodger]
      #816008 - 02/03/10 01:33 PM
You may also find this review I wrote of Nugen Audio's SEQ Linear Phase plug-ins of help, since towards the end I describe how various linear phase designs sound in practice:

www.soundonsound.com/sos/jan08/articles/nugenplugins.htm

To my ears, Waves' LinEQ has an uncanny knack of being able to alter spectral balance without adding any character of its own; if you dial in more bass, for instance, you get more bass, but the sound somehow doesn't seem to be any 'warmer'. This absolute neutrality is ideal for some mastering applications, but not universally enjoyed.


Martin

--------------------
YewTreeMagic


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Shambolic Charm



Joined: 13/07/05
Posts: 968
Re: Linear Phase EQ new [Re: Dodger]
      #816277 - 03/03/10 09:45 AM
while were on the subject, are there any linear phase eq's that have a low latency?

--------------------
www.myspace.com/shambolic-charm


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Martin WalkerModerator
Watcher Of The Skies


Joined: 28/02/01
Posts: 17716
Loc: Cornwall, UK
Re: Linear Phase EQ new [Re: Dodger]
      #816364 - 03/03/10 02:12 PM
Linear phase and low latency don't tend to go hand in hand I'm afraid


Martin

--------------------
YewTreeMagic


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
MarcusH



Joined: 02/02/08
Posts: 461
Loc: Tanzania
Re: Linear Phase EQ new [Re: Dodger]
      #816518 - 03/03/10 10:10 PM
Can't find it now, but I saw a video on the internet showing magnified, the changes to the waveform that Logic's normal Channel EQ makes. Using a kick drum track, the guy showed that Logic's EQ definitely created 'ghosting' - a second hit was clearly visible. More importantly, to my ears Channel EQ sounds dull and lacks clarity.

I do use Logic's Linear Phase EQ however, and there's a good trick to using it. Logic lets you switch between Channel EQ and Linear Phase EQ and the good bit is it keeps your settings. That means you can use Channel EQ when you need low latency - e.g. for tracking, and Linear Phase when you need good sound - e.g. for mixing.

In terms of practical use, I use my third party EQ plugins to improve the sound, and I use Linear Phase EQ for precise jobs, like filtering-out rumble or taking the ring out of a drum sound.

--------------------
You live. You learn.


Post Extras: Print Post   Remind Me!   Notify Moderator     Back to top
Pages: 1

Rate this thread

Jump to

Extra Information
2 registered and 36 anonymous users are browsing this forum.

Moderator:  David Etheridge, James Perrett, zenguitar, Martin Walker, Hugh Robjohns, Zukan, Frank Eleveld, SOS News Editor 
Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is enabled
      UBBCode is enabled
Rating:
Thread views: 5141

December 2014
On sale now at main newsagents and bookstores (or buy direct from the
SOS Web Shop)
SOS current Print Magazine: click here for FULL Contents list
Click image for December 2014
DAW Tips from SOS

 

Home | Search | News | Current Issue | Tablet Mag | Articles | Forum | Blog | Subscribe | Shop | Readers Ads

Advertise | Information | Privacy Policy | Support | Login Help

 

Email: Contact SOS

Telephone: +44 (0)1954 789888

Fax: +44 (0)1954 789895

Registered Office: Media House, Trafalgar Way, Bar Hill, Cambridge, CB23 8SQ, United Kingdom.

Sound On Sound Ltd is registered in England and Wales.

Company number: 3015516 VAT number: GB 638 5307 26

         

All contents copyright © SOS Publications Group and/or its licensors, 1985-2014. All rights reserved.
The contents of this article are subject to worldwide copyright protection and reproduction in whole or part, whether mechanical or electronic, is expressly forbidden without the prior written consent of the Publishers. Great care has been taken to ensure accuracy in the preparation of this article but neither Sound On Sound Limited nor the publishers can be held responsible for its contents. The views expressed are those of the contributors and not necessarily those of the publishers.

Web site designed & maintained by PB Associates | SOS | Relative Media