Help with Equalization

[Alberto Carlassare]

Hi!

I measured my room response for my 5.0 bm5 mkIII loudspeakers witha behringer ecm8000. Obviously main problems were found in under 300 Hz. So I generate an equalization curve for each loudspeaker. The equalization seems to be very interesting in low frecuency, let them more clean, but I don’t understand why REW calculate also a lot of hf attenuation loosing a lot of information above 5kHz. I dont undersand why and If I am doing something wrong.

I leave here the measures if someone wants to answer me. https://www.dropbox.com/s/fi9yga6ghhl5u0f/19-02-27_AC_StudioMeasurements_ECM8000.mdat?dl=0

Thanks

 

[John Mulcahy]

Lots of measurements, but none of them include filters so difficult to comment specifically. The main factors that influence where REW applies filters are:

• The Match Range setting in the Filter Tasks pane, that tells REW the frequency span within which it should calculate filters. Best limiting filters to the range below a few hundred Hz.
• The Target type and Target Level settings in the Target Settings pane. The type tells REW what kind of response shape you expect or want to see, the level controls where that shape sits relative to the measurement - ideally it more or less runs through the middle of the measurement. REW calculates filters to bring the measurement in line with the target.

 

[Alberto Carlassare]

Hi John,

Thank you for you reply. I copy here [ https://goo.gl/zXXSoZ ] a link with only 1 measurement per speaker from the listening position and with filters calculated. The Target Type is Full Range (my bm5 mkii are 48-21kHz) and Target Level is 83dB for LCR and 80dB for Surround. I measures with a 80 dBC SPL (of course surround at 77dBC) but for the curve I see 83 is a better average and I supposed less filter are needed to get it.
The Match Range is 20 to 20kHz -> Maybe my probles is here. You tell me is better to filter under lets say 2-3kHz? I suppose it should be fine, my low frecuency filters seemed to be working great, But why filtering is needed?

 

[John Mulcahy]

That makes things easier, thanks. I'd use 200 - 300 Hz as the upper limit for filtering. Your filters look to be calculated against a target which has room curve settings active, a rise at low frequencies and a fall at HF - if I turn on the room curve settings I get an exact match. If I turn those off there is no filtering at high frequencies as the response is very flat anyway. The target is shown on the EQ graph.

 

[Alberto Carlassare]

When you say "I'd use 200-300 Hz as th eupper limit for filtering" you mean you set Match Range in between 20 and 300Hz ? It makes sense to me. Is this suitable for my situation?

I calculated filters with that curve settings because is what comes by default, I'm not sure about what is really correct in that and how to turn off (Just set LF Cutoff and HF Fall Start outside 20-20k?)

 

[John Mulcahy]

Sounds like you are running 5.19, on that version set the slopes to zero. 20 to 300 is fine.

 

[Alberto Carlassare]

Yeah I'm running 5.19 - I think is latest. Ok Setting slopes to 0 is sure best way. Thanks a lot for the support, really fast and useful!

PD: Last question: I'm using EQuilibrium to add filter to the Master Out. Is it Ok to use "Generic" Some other suggestions in order to get best results

 

[John Mulcahy]

A bit difficult to say, the EQuilibrium talks about a "Music" setting that alters the interaction between gain and Q for the DMG peak filters. No idea what settings that can have of what the effect is. The "Generic" filters have Q values that are based ion the half-gain filter width and are not affected by gain. Your best bet may be to make some loopback measurements of some DMG filter settings and see which (if any) of REW's equaliser options product the same filter shapes with the same parameter values.