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Help with REW & miniDSP Flex room correction for noob

aikofan

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I spent the afternoon yesterday playing around with my new Flex and REW in my 2.1 system. Here’s what I ended up at:

Graph 20220525.jpg


I was targeting a Harman curve, and the REW auto EQ only gave me one filter, a cut around 29 Hz, so I added 4 more manual filters, with boosts ranging between 4 and 6 dB, between 58 and 180 Hz to fix some dips.

I’m also using what’s probably a non-standard crossover of 80 high pass and 50 low pass, both 1st order slopes. The reason why I‘m using such gentle slopes is because my mains (Magnepan .7) had smoother response in the bass than my sub (JL Audio D110), maybe because of the dipole dispersion or the pair vs single sub. The big peaks and valleys were pretty much in the same place in both the sub and mains measured separately (room issues), but they were smaller with the mains. So I’m trying to primarily hear the Maggies’ bass (which sound good and snappy to me, except lightweight and not balanced with the higher frequencie), with reinforcement from the sub, with the sub basically taking over below 40 Hz where the Maggies drop off.

So does anyone have any suggestions for improving this?
  • Also, should my adding a few 6 dB or less EQ boosts make me worried about reducing input levels in my Flex to avoid digital clipping, or does it have enough internal headroom that this would be highly unlikely?
  • I limited myself to 6 dB max for my filters and left everything above 200 Hz alone based on various things I read (some in this forum), but ideally, I would like the dip between 150 and 300 Hz raised up more like 10 dB to make that sag smoother. Is that futile, and are the gentle boosts I used here the best I can do via digital correction?
 

DJBonoBobo

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Looks very bassy to me. Do you like the amount of bass? What´s the listening distance?

I suggest not using 1/6 but "var" smoothing for better resolution in bass area.

Personally, i would at least try something like -3db 400 Hz Q 2 (just eyeballing - you know what i mean) for more balance instead of pumping up the 200Hz area. Low-q-adjustments in this area are ok, i guess.
Personally, i would also reduce the bass at least -6dB, but that´s up to your taste, of course.
 
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aikofan

aikofan

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Looks very bassy to me. Do you like the amount of bass? What´s the listening distance?

I suggest not using 1/6 but "var" smoothing for better resolution in bass area.

Personally, i would at least try something like -3db 400 Hz Q 2 (just eyeballing - you know what i mean) for more balance instead of pumping up the 200Hz area. Low-q-adjustments in this area are ok, i guess.
Personally, i would also reduce the bass at least -6dB, but that´s up to your taste, of course.
I grabbed one of the target curves from this thread. But you’re right, the overall rise in the bass looks like it’s above the target. Maybe I should reduce my boosts in the 58 and 75 Hz areas. The balance sounds OK to me though, because before EQ it sounds a little too bright to me. I read in a few places that any adjustments above 200 Hz should only be based on anechoic measurement, so I was afraid to mess with it. Thanks for your suggestion.
 

DJBonoBobo

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I read in a few places that any adjustments above 200 Hz should only be based on anechoic measurement, so I was afraid to mess with it.
When using only low q values, you are not messing too much with the characteristics of the speakers. For example, you could also safely adjust treble with a very low q (broadband) filter to your taste. But i think it´s important to validate through listening tests. So i am only suggesting to try this - not sure if it works for you eventually.
 
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aikofan

aikofan

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When using only low q values, you are not messing too much with the characteristics of the speakers. For example, you could also safely adjust treble with a very low q (broadband) filter to your taste. But i think it´s important to validate through listening tests. So i am only suggesting to try this - not sure if it works for you eventually.
Definitely worth a try, thanks. Glad I have a long weekend coming up so I can haul out the mic, USB extension cable, and ear muffs again and play around some more.
 

DJBonoBobo

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The measurements don´t need to be very loud. If you try you´ll see there is not much difference. I also suggest trying the MMM method (moving microphone).
 
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aikofan

aikofan

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The measurements don´t need to be very loud. If you try you´ll see there is not much difference. I also suggest trying the MMM method (moving microphone).
Do the sweeps have to at least reach 75 dB? Even that bothers me. I’m the type that wears earplugs when I vacuum the house. Moving the mic is a good suggestion for a next step.
 

DJBonoBobo

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Do the sweeps have to at least reach 75 dB? Even that bothers me. I’m the type that wears earplugs when I vacuum the house. Moving the mic is a good suggestion for a next step.
If i am playing around, i am mostly using sweeps only around 65-70 dB. But i suggest you try out for yourself if you see different behaviour. It depends on your room, furniture, doors, windows and so on. It also depends on background noise and what microphone you use. Just make a loud and a quiet sweep and see for yourself if they are much different.

If you are using quiet sweeps the chance is higher that you are getting invalid results (car driving by, touching something...). For me, personally, it is more important to try out a lot of different sweeps, so i trade this risk for being more comfortable during the measurements. If i think i am satisfied i do a louder sweep afterwards to validate.

Loud sweeps are necessary if you are looking for reverberation time.
 

deercreekaudio

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Have you experimented with high and low shelf filters, playing with them like real-time bass and treble controls?
 
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