Topic: Recommended reading for EQ

Hi all.

I'm the proud owner of an RME ADI-2 DAC and absolutely love it and it's features!

My current set up is:

OPPO UDP 203 - COAX - RME - Arcam SR250
PS4 - OPTICAL - RME - Arcam SR250
Innuos music server - USB - RME - Arcam SR250

I have got to grips with everything as far as set up is concerned but it's the parametric EQ I'm uncertain on.

Can anybody recommend a good book to read or website to look at where I can learn how to accurately adjust the parametric EQ of the RME to further improve my listening.

I'm in a lounge so not a dedicated listening room so obviously room modes are something I would like to play around with.
I think using it "flat" sounds really good but I'm aware there are occasions where some EQ will benefit me.

The Arcam has DIRAC built in and that works wonders for my room, I just want to be able to do something similar for the RME..

Any thoughts guys?

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

2 (edited by Curt962 2019-07-17 12:28:31)

Re: Recommended reading for EQ

Hi Sparky,

A good place to start would be to perform a bit of Room Analysis using one of the fine Sftwr Tools avalable, and a Simple USB Mic.  My Fave is ROOM EQ WIZARD, and it will give you some great insights regarding
Issues in your Room that need to be addressed.   We're Flying Blind until we know what EQ measures are actually needed.    REQ is Neat!  Free Download, and Lots of good Tutorials on-line to help you. 

https://www.roomeqwizard.com/

Sample Tutorial:

https://m.youtube.com/watch?v=-A8LjsOx6d0

Fun Stuff!

Curt

Re: Recommended reading for EQ

Curt962 wrote:

Hi Sparky,

A good place to start would be to perform a bit of Room Analysis using one of the fine Sftwr Tools avalable, and a Simple USB Mic.  My Fave is ROOM EQ WIZARD, and it will give you some great insights regarding
Issues in your Room that need to be addressed.   We're Flying Blind until we know what EQ measures are actually needed.    REQ is Neat!  Free Download, and Lots of good Tutorials on-line to help you. 

Fun Stuff!

Curt

Hi Curt.

I do use REW as it happens but there's a lot to learn when it comes to using it.
I guess the best thing to do is to run a sweep between 20hz - 20Khz to see where the peaks and troughs are and EQ them out bit by bit.
I think it's the low end that will need looking at the most.

I still would like to actually learn about EQ though so I'm open to suggestions for reading material... smile

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

Re: Recommended reading for EQ

Well Sparky, it's difficult to make arbitrary EQ suggestions without actual data, and you should be aware that EQ alone can't fix everything.  Nulls in the FR are a fine example. 

How Large is your Room?  What do You find lacking in SQ?

IMO, getting our Speakers to "get along"  with Our Rooms via EQ, and other measures is one of most fascinating.   aspects of Audio!  smile     It never gets old.   Frustrating at times Yes.   Old?  No. smile

Fill Us in!

Curt

5 (edited by Jas0_0 2019-07-17 14:37:04)

Re: Recommended reading for EQ

I found this guide really useful for learning how to take good measurements and then using REW’s EQ functionality to calculate filters (the next step of importing them into Roon is obviously irrelevant). 

https://community.roonlabs.com/t/a-guid … roon/23800

However, I think this author goes too far I trying to attain a completely flat response. I would avoid adding gain to try to counteract troughs and I wouldn’t recommend correcting above around 250Hz - and if you really feel the need to, only with low Q filters.

I would also not use anywhere as many filters.  The 5 available on the RME has proved adequate - just focus on correcting the biggest frequency spikes.   

Hope that helps

J

Re: Recommended reading for EQ

I concur with Jas0._O's comment on Focusing your efforts on correction of the largest Peaks, that are typically found in the Bass Range.  That's effort well invested!

Curt

7 (edited by Sparkydude 2019-07-17 18:59:15)

Re: Recommended reading for EQ

Curt962 wrote:

Well Sparky, it's difficult to make arbitrary EQ suggestions without actual data, and you should be aware that EQ alone can't fix everything.  Nulls in the FR are a fine example. 

How Large is your Room?  What do You find lacking in SQ?

IMO, getting our Speakers to "get along"  with Our Rooms via EQ, and other measures is one of most fascinating.   aspects of Audio!  smile     It never gets old.   Frustrating at times Yes.   Old?  No. smile

Fill Us in!

Curt

Hi Curt.

Yeah, agreed on your info regarding room issues.
I'm aware that a null will always be a null... You can boost it all you want but you're boosting a null so it's not possible.
I think the only way to combat a null is to either move your listening position or speakers to change the point in the room at which the null appears.
Peaks can be tamed but null cannot. Unfortunately.

Even the much fabled DIRAC can't sort that out but what it can do (or does do) is average the response which gives an overall excellent result.

My room is an average 3 bed semi type so small at L - 5.2 metre W - 4.4 and the usual ceiling height of 2.6 metre.
I have a pair of Spendor A7 speakers which I use for both movies and music.
With movies I have dual BK XXLS 400 down firing subs which work very well with DIRAC engaged but without DIRAC, room modes rear their ugly head.

I can only have the fronts a foot from the front wall but due to the positioning of the k itchen door, my right speaker is around half a foot from the right wall which isn't ideal really.
I was considering an acoustic panel for that part of the wall to mop up that 1st reflection point.
Dunno if the wife would accept that though. big_smile

I guess I don't find anything "lacking" as such but I'm the sort of person that always wonders if I could do better.

I love this game though and love tinkering and learning.

It's an expensive but very enjoyable hobby..

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

Re: Recommended reading for EQ

I don't know what that "I AM A SPAMMING IDIOT" comment is or where it came from?

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

Re: Recommended reading for EQ

Jas0_0 wrote:

I found this guide really useful for learning how to take good measurements and then using REW’s EQ functionality to calculate filters (the next step of importing them into Roon is obviously irrelevant). 

https://community.roonlabs.com/t/a-guid … roon/23800

However, I think this author goes too far I trying to attain a completely flat response. I would avoid adding gain to try to counteract troughs and I wouldn’t recommend correcting above around 250Hz - and if you really feel the need to, only with low Q filters.

I would also not use anywhere as many filters.  The 5 available on the RME has proved adequate - just focus on correcting the biggest frequency spikes.   

Hope that helps

J

I'll check out the link for REW definitely mate.

I never let DIRAC do any EQ above 500hz so I'll carry that over into the RME once I've learnt how to use it properly.....

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

10 (edited by Curt962 2019-07-17 19:40:35)

Re: Recommended reading for EQ

Hey Sparky,

I'm here in the States, so I'm doing some loose calculations in my head.   Metres/Feet whatever...either way, your room is very nearly Square, and this places Length/Width Modes nearly atop of one another. 

  Mental Math says somewhere around 40hz is your first problem area.   (An Open "E" on a Bass Guitar will be BIG)

I'm a big fan of Room Treatments, but 40hz is tough.   Speaker/Seating Positioning  will help lessen the problem (at that ONE POINT) in the Room, and EQ could perhaps help Fine Tune a bit further.   We'll discuss RT60s another time. smile

Curt

Oh BTW!!   We're all a bit remiss in not Welcoming You to the Forum!   Welcome!

11 (edited by ramses 2019-07-17 19:59:10)

Re: Recommended reading for EQ

Hi Curt,

after browsing through the roon information of using REW it seems to me its kind of room corretion by EQ,
but its doesnt seem to be the correction of the room itself, is that correct ?

Because when doing room correction you look at waterfall diagrams etc like in this room optimization:

http://www.tonstudio-forum.de/blog/inde … ileContent

I think in the near future I will try Sonarworks 4 Reference to see whether it brings improvements.
I can use it for my monitors and also for the HiFi in two szenarios:
- PC as music player and eventually, if latency is not too high:
and
- Audio Signals coming from TV, Bluray to ADI-2 FS (once available) -> via ADAT to UFX+
  -> to PC for Sonarworks optimization, then back -> via UFX+ -> ADAT -> ADI-2 DAC -> HiFi
   Not sure whether its worth it, simply want to try.

BR
Ramses
X10SRi-F, Win7 Prof, Cubase 9.5, UFX+, Octamic XTC, ADI-2 Pro FS BE/DAC, RayDAT, ARC USB

12 (edited by Curt962 2019-07-17 20:15:35)

Re: Recommended reading for EQ

Ramses, Precisely. 

REW is for the My Purposes, ONLY an Analysis Tool to afford me insights as to WHAT needs attention.    Much like a Physician would use an MRI, or X-Ray to assess/diagnose a Patient.   From there, The Doctor himself conducts treatment.  Much like no DRC can overcome Physics, There is NO button for the Arzt o push to suddenly make the Patient Well again. smile

With REW...Sometimes I MYSELF have to move the damned Furniture, and Speakers.

Quite Revealing, and how many actually KNOW their most damning RT60 number?

153ms at 40hz here thank you. smile

13 (edited by Sparkydude 2019-07-17 21:24:27)

Re: Recommended reading for EQ

Curt962 wrote:

Hey Sparky,

I'm here in the States, so I'm doing some loose calculations in my head.   Metres/Feet whatever...either way, your room is very nearly Square, and this places Length/Width Modes nearly atop of one another. 

  Mental Math says somewhere around 40hz is your first problem area.   (An Open "E" on a Bass Guitar will be BIG)

I'm a big fan of Room Treatments, but 40hz is tough.   Speaker/Seating Positioning  will help lessen the problem (at that ONE POINT) in the Room, and EQ could perhaps help Fine Tune a bit further.   We'll discuss RT60s another time. smile

Curt

Oh BTW!!   We're all a bit remiss in not Welcoming You to the Forum!   Welcome!

Thanks for the welcome! smile

Ah, you're in the States... I'm over in England.

You're spot on with your calculation of 40hz! I'm amazed that you just know that off the top of your head! How did you do that??!?!?!

I can't seem to post pictures yet but I ran a DIRAC sweep back in January and I have a HUGE room mode at bang on 40hz.
Its a peak and it extends just short of 20dB over the 75dB limit I set for home movie listening.
It then drops into a null of similar proportions into the 80-90hz range then seems to flatten out.

Taming that sort of room mode would take some serious sized bass traps!!

I'm intrigued by this RT60 you've mentioned.... What is that??
If it's too much to go into right now then that's fine mate.

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

14 (edited by Curt962 2019-07-17 21:51:24)

Re: Recommended reading for EQ

Ahh Sparky!   My Wife has all sorts of Kin in the UK...wankers all. smile  Beautiful Place.

In Feet...Simply take:  565/Room Dimension in Feet to arrive at the first mode. 

RT60s.  Hmm.   RT=Reverberation Time.

The "60" refers to the amount of time required for a Sound to diminish 60db. 

Not sure that there is a de-facto standard for "Best" RT60, but less is generally better.  The longer a Room reverberates a Note...the more it muddies up the notes that follow.  "Articulation" is the word I like.

Lower RT60s typically yield a more detailed, clearer sound.  All this coming from a person who has had Work Domiciles with RT60s more easily measured with a Bleedin' Calendar!!  Abysmal Rooms.

It's all fun to dig into, and I/ we're ALL thrilled to see your eagerness to dig deeper into the technicals!  Great Fun Mate, and it's Super having you join in!

All the Best!!

Curt

15 (edited by Curt962 2019-07-17 22:31:32)

Re: Recommended reading for EQ

Sparkydude wrote:
Curt962 wrote:

Hey Sparky,

I'm here in the States, so I'm doing some loose calculations in my head.   Metres/Feet whatever...either way, your room is very nearly Square, and this places Length/Width Modes nearly atop of one another. 

  Mental Math says somewhere around 40hz is your first problem area.   (An Open "E" on a Bass Guitar will be BIG)

I'm a big fan of Room Treatments, but 40hz is tough.   Speaker/Seating Positioning  will help lessen the problem (at that ONE POINT) in the Room, and EQ could perhaps help Fine Tune a bit further.   We'll discuss RT60s another time. smile

Curt

Oh BTW!!   We're all a bit remiss in not Welcoming You to the Forum!   Welcome!

Thanks for the welcome! smile

Ah, you're in the States... I'm over in England.

You're spot on with your calculation of 40hz! I'm amazed that you just know that off the top of your head! How did you do that??!?!?!

I can't seem to post pictures yet but I ran a DIRAC sweep back in January and I have a HUGE room mode at bang on 40hz.
Its a peak and it extends just short of 20dB over the 75dB limit I set for home movie listening.
It then drops into a null of similar proportions into the 80-90hz range then seems to flatten out.

Taming that sort of room mode would take some serious sized bass traps!!

I'm intrigued by this RT60 you've mentioned.... What is that??
If it's too much to go into right now then that's fine mate.

Sparky, that Null you see at 80hz is the UnWelcome First Cousin of your fundamental Room Modes.  As an Analogy:
think of "Anslo" in "Keeping up with Appearances"   smile  (UK Television)

The 70-80hz freq range being nulled out is also often why a Kick Drum sounds a bit like a Cabbage in a Cardboard Box.   Mull that over.  We've all heard it.  Not really "inspiring"

Now we're on the same page...  smile

16

Re: Recommended reading for EQ

Sparkydude wrote:

I don't know what that "I AM A SPAMMING IDIOT" comment is or where it came from?

Usually typo. For example if you write c h a n e l instead of channel the same will happen wink

I made your room door visible with the same trick. Too many spammers that try to sell that, sorry.

Regards
Matthias Carstens
RME

Re: Recommended reading for EQ

Curt962 wrote:
Sparkydude wrote:
Curt962 wrote:

Hey Sparky,

I'm here in the States, so I'm doing some loose calculations in my head.   Metres/Feet whatever...either way, your room is very nearly Square, and this places Length/Width Modes nearly atop of one another. 

  Mental Math says somewhere around 40hz is your first problem area.   (An Open "E" on a Bass Guitar will be BIG)

I'm a big fan of Room Treatments, but 40hz is tough.   Speaker/Seating Positioning  will help lessen the problem (at that ONE POINT) in the Room, and EQ could perhaps help Fine Tune a bit further.   We'll discuss RT60s another time. smile

Curt

Oh BTW!!   We're all a bit remiss in not Welcoming You to the Forum!   Welcome!

Thanks for the welcome! smile

Ah, you're in the States... I'm over in England.

You're spot on with your calculation of 40hz! I'm amazed that you just know that off the top of your head! How did you do that??!?!?!

I can't seem to post pictures yet but I ran a DIRAC sweep back in January and I have a HUGE room mode at bang on 40hz.
Its a peak and it extends just short of 20dB over the 75dB limit I set for home movie listening.
It then drops into a null of similar proportions into the 80-90hz range then seems to flatten out.

Taming that sort of room mode would take some serious sized bass traps!!

I'm intrigued by this RT60 you've mentioned.... What is that??
If it's too much to go into right now then that's fine mate.

Sparky, that Null you see at 80hz is the UnWelcome First Cousin of your fundamental Room Modes.  As an Analogy:
think of "Anslo" in "Keeping up with Appearances"   smile  (UK Television)

The 70-80hz freq range being nulled out is also often why a Kick Drum sounds a bit like a Cabbage in a Cardboard Box.   Mull that over.  We've all heard it.  Not really "inspiring"

Now we're on the same page...  smile


Ah, that unwelcome first cousin is a definite no no. Problem is, there is literally nothing I can do to remove that is there? I have no room for manoeuvre as far as placement of speakers or listening position is concerned.

Your analogy of the sound at 70-90hz is spot on mate!
Tell you what, I wish I had your knowledge of these things!

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

Re: Recommended reading for EQ

MC wrote:
Sparkydude wrote:

I don't know what that "I AM A SPAMMING IDIOT" comment is or where it came from?

Usually typo. For example if you write c h a n e l instead of channel the same will happen wink

I made your room door visible with the same trick. Too many spammers that try to sell that, sorry.

Ah right. I just thought you guys didn't like me! big_smile

Just want to congratulate you guys at RME for developing such a fantastic product!
I'm over the moon with it....

Cheers. smile

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

19 (edited by Curt962 2019-07-18 12:04:55)

Re: Recommended reading for EQ

Sparky,

Indeed the ADI-2DAC is a Jewel!!   

With regard to your Room, let's try applying a Low-Cut Filter. (  I know...HORROR!  )

Your PEQ allows you to create such a filter quite easily. 

Band 1:  50hz
Gain:  Start around -8db. 

On the Right Side of the Display you"ll see a little 3-Pointed Symbol.  Selecting that will plot out your Lo Cut filter on the Display.   Save this EQ, and give it a listen.   Season to Taste.  smile

Herein,  we're loosely replicating the LF Output of a Smaller Speaker that simply does not excite the 40hz Room Modes as greatly.   Purely Experimental of course, and it can all be erased with the push of a button.   

We can't Fight Physics, so let's see if we can work WITH them.   smile

Give it a Whirl!

Curt

Re: Recommended reading for EQ

This is very good advice! In music production we do this all the time. Removing unneeded low and even high end from an instrument or a sound. The brain has this interesting capability of adding the missing low end, but only after you have forgotten you set this.

Vincent, Amsterdam
https://soundcloud.com/thesecretworld
HDSP9652+ADI-8AE  2X HDSP9632
Cubase pro10

Re: Recommended reading for EQ

I'm also playing with REW and the Umik-1.
A question: do you calibrate left then right or both at the same time?

ADI-2 DAC - Neumann KH 310 A monitors

Re: Recommended reading for EQ

Noob,

I only use One Mic.   It was supplied with Cal Data that was input to REW.   

Your Mic interface would likely have negligible FR variations, so I think creating a cal file for that is strictly optional.

Re: Recommended reading for EQ

Curt962 wrote:

Noob,

I only use One Mic.   It was supplied with Cal Data that was input to REW.   

Your Mic interface would likely have negligible FR variations, so I think creating a cal file for that is strictly optional.

Excuse me, my post wasn't clear: do you calibrate left speaker and then right speaker (2 measures), or just one mesure with both speakers active?

ADI-2 DAC - Neumann KH 310 A monitors

24 (edited by Curt962 2019-07-18 15:00:19)

Re: Recommended reading for EQ

N00b wrote:
Curt962 wrote:

Noob,

I only use One Mic.   It was supplied with Cal Data that was input to REW.   

Your Mic interface would likely have negligible FR variations, so I think creating a cal file for that is strictly optional.

Excuse me, my post wasn't clear: do you calibrate left speaker and then right speaker (2 measures), or just one mesure with both speakers active?


Ahhh So.  Noob,  I listen to both Speakers at the same time, so that's how I would typically measure.  A Whole System Composite Picture. 

Surely though, you can measure each Speaker individually, and this could be very useful in certain diagnostic tests. 

Curt

25 (edited by Curt962 2019-07-18 15:15:20)

Re: Recommended reading for EQ

Noob, et al...

This REW Tutorial is excellent.   Once you sort thru the first minute or so of Stuff, you get a VERY CLEAR, UP CLOSE look at how to proceed with REW.     Recommended!

https://m.youtube.com/watch?v=e4uSR3cUUSY

Curt

Re: Recommended reading for EQ

Curt962 wrote:

Ahh Sparky!   My Wife has all sorts of Kin in the UK...wankers all. smile  Beautiful Place.

In Feet...Simply take:  565/Room Dimension in Feet to arrive at the first mode. 

RT60s.  Hmm.   RT=Reverberation Time.

The "60" refers to the amount of time required for a Sound to diminish 60db. 

Not sure that there is a de-facto standard for "Best" RT60, but less is generally better.  The longer a Room reverberates a Note...the more it muddies up the notes that follow.  "Articulation" is the word I like.

Lower RT60s typically yield a more detailed, clearer sound.  All this coming from a person who has had Work Domiciles with RT60s more easily measured with a Bleedin' Calendar!!  Abysmal Rooms.

It's all fun to dig into, and I/ we're ALL thrilled to see your eagerness to dig deeper into the technicals!  Great Fun Mate, and it's Super having you join in!

All the Best!!

Curt

I'm glad to be here mate! Sounds like you lot love what you do and I'm glad to be a part of it..

By the way, I didn't see this message at all for some reason until now??
My wife also has kin over in the States! Toss-pots the lot of 'em. big_smile
Some in Utah and some over in New York.

Thanks for the info regarding the RT times!
That's really really interesting!
If my room RT falls on 40 & 80hz then you're spot on with what you're saying! smile

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

Re: Recommended reading for EQ

Curt962 wrote:

Noob, et al...

This REW Tutorial is excellent.   Once you sort thru the first minute or so of Stuff, you get a VERY CLEAR, UP CLOSE look at how to proceed with REW.     Recommended!

https://m.youtube.com/watch?v=e4uSR3cUUSY

Curt

Thanks Curt!

ADI-2 DAC - Neumann KH 310 A monitors

Re: Recommended reading for EQ

Sparky,

For Audio Measurement Purposes, RT60s are more commonly displayed across a Range of Frequencies.   The Resultant Graph is called a "Waterfall" because that is quite what it looks like!    In a Perfect World, the amplitudes of the entire range of frequencies measured would simply plunge vertically,  with perfect uniformity into nothingness the instant that the test signal stopped.   

That doesn't happen in our Rooms.  Some Frequency Ranges tend to loiter about a bit longer.  So, to summarize, that test indicates how quickly Sounds diminish in level within our Rooms.     Clever Stuff.

Re: Recommended reading for EQ

Two last questions:
- On audio forums, I've red that REW use what Rephase software calls "proportional Q". And by default, Rephase is set on "Constant Q". Do you knwo if the RME ADI-2 Pro/DAC use proportionnal or constant Qs ?
- The filters in the RME EQ, IIR or FIR? I've red it's better to correct both speakers together if the filter is non phase linear...

ADI-2 DAC - Neumann KH 310 A monitors

30 (edited by Curt962 2019-07-18 16:54:56)

Re: Recommended reading for EQ

Noob,

I don't have a Clue.   Best to let MC tackle that question.    Careful what you read online though...especially in those "other" Audio Forums. smile

Re: Recommended reading for EQ

Sparky??  The Suspense is Killing me!  Now is not the time for a Pint Mate  smile

  Try the Low-Cut filter!

I have MY Celebration Pint at the ready. smile

Re: Recommended reading for EQ

Curt962 wrote:

Sparky??  The Suspense is Killing me!  Now is not the time for a Pint Mate  smile

  Try the Low-Cut filter!

I have MY Celebration Pint at the ready. smile


Awww mate I'm sorry but you'll have to put that pint on hold!
I'm an electrician and I work away from home Monday-Friday so play time is a weekend thing only...

And that's AFTER I've played with the kids for a bit.. big_smile

Wife would murder me if I just waltzed straight in, ignored her and the kids and jumped straight into EQ'ing.. big_smile

Sorry to put a dampner on it...

I've just got to my hotel....

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

33 (edited by Curt962 2019-07-18 19:19:46)

Re: Recommended reading for EQ

No Worries!   

Mind you, all that talk about Waterfall Graphs made me thirsty!  So,  For purely Scientific Reasons I drank my Pint.   You know...Strictly in the name of Science. (Somewhat)

Now I'm merely repeating the Test to Validate my Results.   smile

Get some Rest Mate!

34 (edited by Sparkydude 2019-07-18 19:48:18)

Re: Recommended reading for EQ

Curt962 wrote:

No Worries!   

Mind you, all that talk about Waterfall Graphs made me thirsty!  So,  For purely Scientific Reasons I drank my Pint.   You know...Strictly in the name of Science. (Somewhat)

Now I'm merely repeating the Test to Validate my Results.   smile

Get some Rest Mate!

big_smile

You drank your pint in the name of science and all that is audio... Cheers to that...

I'll message you at weekend to let you know how things went... smile

RME ADI-2 - Spendor A7's - Arcam SR250 - BK XXLS400 x 2 - ZEN MINI MK3 with LPSU (as a ROON core)

Re: Recommended reading for EQ

RightO!  I'll be somewhat absent on Saturday due to Work related travel, but if you run into Questions regarding the Low-Filter,  there will likely be a hearty Soul here on the Forum to lend a hand. 

Curt

Re: Recommended reading for EQ

I'm playing with REW, trying to correct the frequencies below 200 Hz... But I can only apply 3 filters, because the 2 last begin at 200 Hz...

ADI-2 DAC - Neumann KH 310 A monitors

37 (edited by Curt962 2019-07-18 23:19:40)

Re: Recommended reading for EQ

N00b wrote:

I'm playing with REW, trying to correct the frequencies below 200 Hz... But I can only apply 3 filters, because the 2 last begin at 200 Hz...

What are you faced with Noob?  Details of what needs correcting?

Curt

Email me a Screenshot if it's convenient for you.

38 (edited by N00b 2019-07-19 00:21:23)

Re: Recommended reading for EQ

Curt962 wrote:
N00b wrote:

I'm playing with REW, trying to correct the frequencies below 200 Hz... But I can only apply 3 filters, because the 2 last begin at 200 Hz...

What are you faced with Noob?  Details of what needs correcting?

Curt

Email me a Screenshot if it's convenient for you.

Hi Kurt!
I was trying to correct my room with REW in the 20-200 Hz range. But when REW generates 5 filters, I can't apply them with the RME: only 3 filters are available in the EQ below 200 Hz, the 2 last must be over 200 Hz.

But I figure it out. With 30-120 Hz correction within 6 dB tolerance, 3 filters only are generated and the result is nice:

https://reho.st/self/4823afe9c14e5cb9ec8c92156ae9e62519b54526.jpg

smile

ADI-2 DAC - Neumann KH 310 A monitors

Re: Recommended reading for EQ

Noob,

That's a rather nice response plot.  The "Plateau" <100hz is curious, but overall very good!

Where did you take this measurement?  Listening Position, or other?

Curt

Re: Recommended reading for EQ

Curt962 wrote:

Noob,

That's a rather nice response plot.  The "Plateau" <100hz is curious, but overall very good!

Where did you take this measurement?  Listening Position, or other?

Curt

Listening position.

The mids and high are not so good... May I try EQ?
Why Sparkydude said "I wouldn’t recommend correcting above around 250Hz"? Is it better to look after the problems in the room itself?

https://reho.st/self/9043b5fec56be8888a0e7cd7f967a9bacac7d057.jpg

ADI-2 DAC - Neumann KH 310 A monitors

41 (edited by Curt962 2019-07-19 01:54:16)

Re: Recommended reading for EQ

Noob,

A fairly typical Room Measurement. 

(Room Analysis Tools are Dangerous tho...  smile  )

Acoustic Treatments would go far in managing things!   Understand that You will never see a Ruler Flat Room Response, and that you will EQ/Acoustically Treat Yourself to complete Madness trying to achieve such.  smile

Acoustic Treatments (as boring as they seem) bring other virtues to the equation such as control of Slap/Flutter Echo, Early Reflections (that destroy Stereo Imaging), and better control of Reverberation Times in the Room.    No EQ alone can manage that. 

First Reflection Points, Corners, etc are fine places to begin.   I like GIK Acoustics here in the States.  Available now in EU as well.  Nicely Crafted Acoustics Products that actually have WAF!  (Wife Acceptance Factor)   smile

Wives:  Good Candidates for "helpers" in the process of identifying First Reflection Points with a Mirror...but I warn you..  smile

"Dear...NO I'M NOT PUTTING SPEAKERS ON THE CEILING!!"

"Just tell me when you see the speaker in the Mirror"

Wife:  "But they're right there on the Stands?"

Oh please God...why?  smile

We got it done.  Eventually, and after MUCH explanation regarding Mirrors...

Enough.

Target the most egregious deviations, but in the end, it's OK to accept "some" variation in FR.   

Curt

42

Re: Recommended reading for EQ

N00b wrote:

Two last questions:
- On audio forums, I've red that REW use what Rephase software calls "proportional Q". And by default, Rephase is set on "Constant Q". Do you knwo if the RME ADI-2 Pro/DAC use proportionnal or constant Qs ?
- The filters in the RME EQ, IIR or FIR? I've red it's better to correct both speakers together if the filter is non phase linear...

While constant Q is well defined, proportional Q is not. There are different versions of it. Old analog graphical EQs have a typical proportional Q behaviour, where at low gains/attenuations the affected area is much too big. While in constant Q it is much too small/narrow. Around 1988 Electro-Voice introduced 'Constant Range' as a useful mix of both. Q is changing, but not as excessive as with typical proportional Q. And at lower gains/attenuations the affected area is not as uselessly small as with typical constant Q ones.

While 'Constant Range' has not survived as known label for such a behavior, the working principle is found in numerous professional devices, mostly not even mentioned that they work this way. Same for our TotalMix and ADI PEQ. We just think this is the way a good EQ should work.

Here is a measurement on how it works, but you see the same live on the ADI's screen.

https://www.rme-audio.de/images/peq_q1.png

https://www.rme-audio.de/images/peq_q5.png

This way of working combines precise operation, band interaction and musicality. Note that the given Q is valid at +6 dB and -6 dB. Higher and lower values change the effective Q value.

The EQs are IIR as we want realtime performance. FIR EQ requires a lot of time = latency which makes it unusable in most live applications.

Regards
Matthias Carstens
RME

43 (edited by jiw 2019-07-19 07:57:22)

Re: Recommended reading for EQ

N00b wrote:

Listening position.

The mids and high are not so good... May I try EQ?
Why Sparkydude said "I wouldn’t recommend correcting above around 250Hz"? Is it better to look after the problems in the room itself?

https://reho.st/self/9043b5fec56be8888a0e7cd7f967a9bacac7d057.jpg

At low frequencies, EQ can be used to ameliorate the effects of both room modes (resonances) and boundary interference (reflections). As those effects are much more pronounced at low frequencies than at mid and high frequencies and the wavelengths at mid to high frequencies are so short that even small movements change the response (e.g. ~17 cm at 2 kHz, i.e. 8.5 cm of movement between boost and dip), using EQ above the low frequencies is much more of a compromise.

In your case, the peaks and dips in the mids and highs are likely due to comb filtering from reflections. Using EQ to try to fix this is futile unless you want to listen in a vice.

Also, unless the arrival time difference between direct and reflected sound is within 5 ms (~1.7 m path length difference), reflected sound will not be integrated with the direct sound by the listener. Thus, the speakers may sound quite different than indicated by the peaks and dips in the measurement.

Try listening and see if you can hear what you see on the measurement. Also move around a bit and see how that affects what you hear.

Also, did you measure both speakers at once? This can lead to cancellation/attenuation if the speakers are not the same distance from the microphone.

Re: Recommended reading for EQ

Curt962 wrote:

Noob,

A fairly typical Room Measurement. 

(Room Analysis Tools are Dangerous tho...  smile  )

Acoustic Treatments would go far in managing things!   Understand that You will never see a Ruler Flat Room Response, and that you will EQ/Acoustically Treat Yourself to complete Madness trying to achieve such.  smile

Acoustic Treatments (as boring as they seem) bring other virtues to the equation such as control of Slap/Flutter Echo, Early Reflections (that destroy Stereo Imaging), and better control of Reverberation Times in the Room.    No EQ alone can manage that. 

First Reflection Points, Corners, etc are fine places to begin.   I like GIK Acoustics here in the States.  Available now in EU as well.  Nicely Crafted Acoustics Products that actually have WAF!  (Wife Acceptance Factor)   smile

Wives:  Good Candidates for "helpers" in the process of identifying First Reflection Points with a Mirror...but I warn you..  smile

"Dear...NO I'M NOT PUTTING SPEAKERS ON THE CEILING!!"

"Just tell me when you see the speaker in the Mirror"

Wife:  "But they're right there on the Stands?"

Oh please God...why?  smile

We got it done.  Eventually, and after MUCH explanation regarding Mirrors...

Enough.

Target the most egregious deviations, but in the end, it's OK to accept "some" variation in FR.   

Curt

lol
Yes, I will try to do what I can do for the room.
And for starters 2 Raiwai acoustic panels are on their way smile


MC wrote:
N00b wrote:

Two last questions:
- On audio forums, I've red that REW use what Rephase software calls "proportional Q". And by default, Rephase is set on "Constant Q". Do you knwo if the RME ADI-2 Pro/DAC use proportionnal or constant Qs ?
- The filters in the RME EQ, IIR or FIR? I've red it's better to correct both speakers together if the filter is non phase linear...

While constant Q is well defined, proportional Q is not. There are different versions of it. Old analog graphical EQs have a typical proportional Q behaviour, where at low gains/attenuations the affected area is much too big. While in constant Q it is much too small/narrow. Around 1988 Electro-Voice introduced 'Constant Range' as a useful mix of both. Q is changing, but not as excessive as with typical proportional Q. And at lower gains/attenuations the affected area is not as uselessly small as with typical constant Q ones.

While 'Constant Range' has not survived as known label for such a behavior, the working principle is found in numerous professional devices, mostly not even mentioned that they work this way. Same for our TotalMix and ADI PEQ. We just think this is the way a good EQ should work.

Here is a measurement on how it works, but you see the same live on the ADI's screen.

https://www.rme-audio.de/images/peq_q1.png

https://www.rme-audio.de/images/peq_q5.png

This way of working combines precise operation, band interaction and musicality. Note that the given Q is valid at +6 dB and -6 dB. Higher and lower values change the effective Q value.

The EQs are IIR as we want realtime performance. FIR EQ requires a lot of time = latency which makes it unusable in most live applications.

Thanks a lot, as always, for the documented and detailed answer... I have learned so much here...


jiw wrote:
N00b wrote:

Listening position.

The mids and high are not so good... May I try EQ?
Why Sparkydude said "I wouldn’t recommend correcting above around 250Hz"? Is it better to look after the problems in the room itself?

https://reho.st/self/9043b5fec56be8888a … c7d057.jpg

At low frequencies, EQ can be used to ameliorate the effects of both room modes (resonances) and boundary interference (reflections). As those effects are much more pronounced at low frequencies than at mid and high frequencies and the wavelengths at mid to high frequencies are so short that even small movements change the response (e.g. ~17 cm at 2 kHz, i.e. 8.5 cm of movement between boost and dip), using EQ above the low frequencies is much more of a compromise.

In your case, the peaks and dips in the mids and highs are likely due to comb filtering from reflections. Using EQ to try to fix this is futile unless you want to listen in a vice.

Also, unless the arrival time difference between direct and reflected sound is within 5 ms (~1.7 m path length difference), reflected sound will not be integrated with the direct sound by the listener. Thus, the speakers may sound quite different than indicated by the peaks and dips in the measurement.

Try listening and see if you can hear what you see on the measurement. Also move around a bit and see how that affects what you hear.

Also, did you measure both speakers at once? This can lead to cancellation/attenuation if the speakers are not the same distance from the microphone.

OK, thanks for all the explanations! I understand these graphics don't explain everything, and to be quite honest, the sound is really good to my ears as it is. I will try to improve the room in the future, but my home is actually the best audio installation I've ever heard.... Please don't wake me up big_smile
And yes, both speakers together measurements. smile

ADI-2 DAC - Neumann KH 310 A monitors

Re: Recommended reading for EQ

Noob,

Good with adding some Treatments to your Room!      Wise Investment. 

Enjoy My Friend!!

Curt

Re: Recommended reading for EQ

Curt sent me this by PM, it is so relevant here! big_smile


https://reho.st/gif/1c29ec9c7eec960d2d23869edf56ec108be6c989.gif

ADI-2 DAC - Neumann KH 310 A monitors

47 (edited by N00b 2019-07-19 20:20:37)

Re: Recommended reading for EQ

Hi guys!
So tonight listening with the corrections... A little flat by our taste...
I would like to « dim » the filters 50%... So I divide the gain by 2... but what about the Q? The same or a coefficient must be set?

ADI-2 DAC - Neumann KH 310 A monitors

48 (edited by Curt962 2019-07-20 00:11:40)

Re: Recommended reading for EQ

Noob,

Sure!  Trim the filter Amplitudes in half, but leave the Q alone.  For now.   We're totally in experimental mode here, so make small adjustments until you reach an EQ that suits your tastes.

"Q" affects the Width of the filter.

Don't forget that handy "Bass" control (encoder 2)!!!   That can Warm things up nicely for you.   

Bon Nuitt!

PS:  Please tell me You have Auto-Ref, and Dynamic Loudness activated...Please!  smile

Curt

49 (edited by N00b 2019-07-20 15:39:22)

Re: Recommended reading for EQ

Yes, indeed: + 4 dB on the bass control (encoder 1 BTW wink ) and it's perfect: no more boomy sound but warm enough for us!
The final EQ:

Filter  1: ON  PK       Fc    46.1 Hz  Gain -10.2 dB  Q 2.000
Filter  2: ON  PK       Fc    69.5 Hz  Gain  -7.8 dB  Q 4.750
Filter  3: ON  PK       Fc    93.2 Hz  Gain   2.8 dB  Q 5.848

And yes: Dynamic Loudness and Auto Vol Ref activated!

ADI-2 DAC - Neumann KH 310 A monitors

Re: Recommended reading for EQ

Excellent!!! smile

Curt