Cool Dude Ted

REW software

Recommended Posts

A quick reply...

What Equaliser do you have selected?

13 minutes ago, Cool Dude Ted said:

1) if I increase ‘smoothing’ of the graphs then the number of frequency settings/changes/reduces. I had to settle on 1/12 smoothing to get a sensible number of parameters 

You can limit the number of filters within the EQ Filters window by unticking ones you don't want and then clicking on 'Match response to target' again.

13 minutes ago, Cool Dude Ted said:

2) I am struggling with understanding the reference to ‘target Dbs’ when measuring. 75 DB seems to be the default but I don’t understand why. This could simply be me struggling with the whole concept of decibels rather than being REW specific.

If you look at the top graph in the EQ section there is a line that shows the target curve. If you change the set target level this line will move to the set value. When you ask it to 'Match response to target' it will try to smooth your measured response to where this line is.

13 minutes ago, Cool Dude Ted said:

3) Increasing/decreasing the volume level on my amp changes the results????

What changes? Posting pictures to show us would help.

13 minutes ago, Cool Dude Ted said:

4) some of the suggested EQ settings are extreme to say the least e.g. a Q of 32 and -50Db. The PEQ within Moode only permits a max Q of 8

You're absolutely right that is extreme and frankly not sensible. In part my guess is that the 75 dB target may be a long way off what you measured, which is likely a result of using your uncalibrated microphone. What sort of levels did you measure?

13 minutes ago, Cool Dude Ted said:

5) Moode doesn’t seem to permit the input of separate settings for L & R speakers. Have I missed something here?

I have no idea as I've never used Moode :). It may not.

  • Upvote 1

Share this post


Link to post
Share on other sites
Super Dealer
32 minutes ago, Cool Dude Ted said:

@MartinC

@PuritéAudio

Thank you both for your help to date.

I took a deep breath and had another go this afternoon. I am not saying that it was a success but I at least arrived at a series of settings which I have been able to input to the PEQ in Moode. I have input 8 settings between 40 Hz and 200 Hz. Have listened for a while but so very difficult to assess if “better” than what went before without A/B listening which I cannot do at present.

A few observations/unanswered questions which I would be delighted to receive responses to if you have the time. I’m sure that the answers are blindingly obvious to anyone who is experienced with REW

1) if I increase ‘smoothing’ of the graphs then the number of frequency settings/changes/reduces. I had to settle on 1/12 smoothing to get a sensible number of parameters 

2) I am struggling with understanding the reference to ‘target Dbs’ when measuring. 75 DB seems to be the default but I don’t understand why. This could simply be me struggling with the whole concept of decibels rather than being REW specific.

3) Increasing/decreasing the volume level on my amp changes the results????

4) some of the suggested EQ settings are extreme to say the least e.g. a Q of 32 and -50Db. The PEQ within Moode only permits a max Q of 8

5) Moode doesn’t seem to permit the input of separate settings for L & R speakers. Have I missed something here?

Thanks.

Can you post a screenshot of your plot?

I would only correct the first few hundred hertz of the response, ie just the low bass, the higher the ‘Q’ the narrower the peak,  1.4 is an octave so 32 doesn’t sound right nor a minus gain of 50dB .

Screen shot the SPL plot and post it.

Keith

Share this post


Link to post
Share on other sites

Thank you both for the replies.

I’m just about to turn in now, so will reply in full tomorrow. Thank you.

Share this post


Link to post
Share on other sites
15 hours ago, MartinC said:

A quick reply...

What Equaliser do you have selected?

You can limit the number of filters within the EQ Filters window by unticking ones you don't want and then clicking on 'Match response to target' again.

If you look at the top graph in the EQ section there is a line that shows the target curve. If you change the set target level this line will move to the set value. When you ask it to 'Match response to target' it will try to smooth your measured response to where this line is.

What changes? Posting pictures to show us would help.

You're absolutely right that is extreme and frankly not sensible. In part my guess is that the 75 dB target may be a long way off what you measured, which is likely a result of using your uncalibrated microphone. What sort of levels did you measure?

I have no idea as I've never used Moode :). It may not.

Thanks.

I have chosed the "generic" equaliser.

re limit number of filters - is unticking only relevant if loading into (say) DSP? I am manually loading into the Moode PEQ.

Re 75 Db target level. This seems to be the default target level set in REW. When you hit the "set target level", it changes. Am I right in thinking this automatic change is directly related to the recorded output levels? I am still struggling to understand the significance of 75 Db.

I am really sorry to admit that I don't understand the question "what sort of levels did you measure". I am probably being very slow here and showing my total inexperience.

I think I am at the point where I undertsand, fundamentally, what REW is trying to achieve but I am getting very lost with the intermediate steps the SW needs to take to get there and not understanding many of the settings (e.g. which are crucial/which can be ignored?) and I seem to understand only one of the graphs - the SPL plot.

Share this post


Link to post
Share on other sites
8 minutes ago, Cool Dude Ted said:

I have chosed the "generic" equaliser.

Sensible.

Quote

re limit number of filters - is unticking only relevant if loading into (say) DSP? I am manually loading into the Moode PEQ.

No. It's relevant to you as it will achieve what you said you were doing with smoothing. Limiting number of filters than can be used.

Quote

Re 75 Db target level. This seems to be the default target level set in REW. When you hit the "set target level", it changes. Am I right in thinking this automatic change is directly related to the recorded output levels? I am still struggling to understand the significance of 75 Db.

I'm not sure but it may always starts at 75 dB and has nothing to do with your measurement. Ignore that it starts at 75 dB and change it to something that looks appropriate for your measurement.

Quote

I am really sorry to admit that I don't understand the question "what sort of levels did you measure". I am probably being very slow here and showing my total inexperience.

If you look at the curve of your measurements what sort of numbers are you seeing? If you could post a picture this would show us. Just use the camera icon to the top left of the main graph.

Edited by MartinC
  • Upvote 1

Share this post


Link to post
Share on other sites
41 minutes ago, MartinC said:

Sensible.

No. It's relevant to you as it will achieve what you said you were doing with smoothing. Limiting number of filters than can be used.

I'm not sure but it may always starts at 75 dB and has nothing to do with your measurement. Ignore that it starts at 75 dB and change it to something that looks appropriate for your measurement.

If you look at the curve of your measurements what sort of numbers are you seeing? If you could post a picture this would show us. Just use the camera icon to the top left of the main graph.

Thanks Martin.

the graphs below are with my amp volume control in the "9am" position and then "10am" position. No smoothing.

9am. When I click "set target level" it automatically changes to 77.8Db. This output produces 9 EQ filter settings in the 20-200Hz range. These range from Q settings of 2.1 to 17.1. Interestingly, there are 3 filters at 92.2, 92.3 and 93 Hz with gains ranging from minus 24.2 to plus 18. These are "crazy" figures and impossible to apply.

10am. Click "set target level" button produces a figure of 84.8Db. This output produces 9 Eq filters with Q values ranging from 4.1 to 29.2. With gains from plus 15Db to minus 19.5. The nonsense in the 92 and 93 Hz range does not appear.

Literally, the only difference between these two graphs is that one was produced with a slightly different volume setting on the amp and I am clueless as to why there should be such an enormous variation in the Eq filters suggested. That said, the overall shape of the two graphs is very similar.

I remain grateful to you for any input/clarification but I cannot expect you to keep giving your time to this issue.

My overriding question now is to what extent, if at all, any issues I am seeing would be overcome by me acquiring a calibrated mic without me needing to understand anything more of the intricacies of REW than I do (or don't) now.

Regards

Stuart

9am no smoothing.jpg

10am no smoothing.jpg

Share this post


Link to post
Share on other sites
16 hours ago, PuritéAudio said:

Can you post a screenshot of your plot?

I would only correct the first few hundred hertz of the response, ie just the low bass, the higher the ‘Q’ the narrower the peak,  1.4 is an octave so 32 doesn’t sound right nor a minus gain of 50dB .

Screen shot the SPL plot and post it.

Keith

Hi Keith

Thanks.

I have posted a couple of graphs in response to Martin's reply above.

Regards

Stuart

Share this post


Link to post
Share on other sites

And just to re-iterate that this is an analogue mic, not calibrated. Plugged into the mic in on an old laptop with "sound out" going from the analogue out on the laptop to my Rega amp.

Share this post


Link to post
Share on other sites
3 minutes ago, MartinC said:

How was your microphone supported for the two measurements above? It looks like it wasn't in the same position for each to me...

Please dont laugh, but it was wedged into a gap inthe the sofa adjacent to my primary listening position.

Share this post


Link to post
Share on other sites

I do have a camera tripod which I could somehow attach the mic to if you think that would be a better solution.

Share this post


Link to post
Share on other sites
Just now, Cool Dude Ted said:

Please dont laugh, but it was wedged into a gap inthe the sofa adjacent to my primary listening position.

Did you take it out and put it back in again between the measurements? Might it have slipped down a bit?

The shapes of two measurements where only the volume has changed should look virtually identical, unless the volume ends up being so high that there is a lot of distortion.

Share this post


Link to post
Share on other sites
Just now, MartinC said:

Did you take it out and put it back in again between the measurements? Might it have slipped down a bit?

The shapes of two measurements where only the volume has changed should look virtually identical, unless the volume ends up being so high that there is a lot of distortion.

Point taken. Although I wasn't aware it had moved, I accept that it could have moved/slipped very slightly between taking the two measurements.

Share this post


Link to post
Share on other sites

It looks like more than a very small movement to be honest. Might anything else have changed? Like a door being open or closed perhaps? 

Next time you get chance try taking a couple of measurements one straight after each other without changing anything, and then with the volume changed. Don't worry about looking at EQ at all, just take the measurements.

To make them more repeatable you could use the time delay feature so you can leave the room before each measurement starts.

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.