Lets talk REW (Room EQ Wiz) and how best to use it.

[joessportster]

7 hours ago, CECAA850 said:

The onlyway you're going to improve the suck out at 50Hz is to physically move things around.  The mic is in a room null there.   Have you measured in other seating positions?

 

Thinking out loud now.  I can't recall your exact set up right now but it's possible you could have some cancellation going on there as opposed to a room null.  If you get the same drop there while measuring in other areas of the room you have a phase issue between your mains and sub or between both subs.  You'll have to start switching polarity around and measuring at that point.

 

Room nulls and phase issues look the same as they're both forms of cancellation. 

Did not know any of that. Will give it a try Thank you....Will take a couple days though Have to have some electric ran..........

[Emile]

OK; beginner at this  Got a Umik-1 mic, MiniDSP 2x4 and downloaded REW.  Testing it on my (back) Cornwall I speakers which are powered by a Yamaha CR-620 ... signal is coming from the "front" (zone 2 pre-out from an Onkyo ZR810 AVR).  

Ran REW on my speakers ("RED" on graph). Let REW "equalize" it (with a "basic" home curve) and loaded the values into the miniDSP. Played a record, comparing "straight" input vs miniDSP input.  Kind of disappointed  The original sound seemed much more dynamic than the modified sound   Do my ears have to get used to it???

Last ran REW calobration on the miniDSP output ("BLUE" on graph). Am I missing something basic???

Thanks, Emile

 

 

add-on ... bypassing low filters; high filter set at 34Hz

[Chris A]

That's a pretty big drooping down ramp starting at 2 kHz upwards.  That's more than 10 dB of droop on the high end.  If you're measuring on-axis at one metre, that droop should be limited to about 3 dB, not 10 dB.  That's a wee bit too much "house curve".

 

You're probably reacting to the fact that you've been listening to that big bass hump centered at 75 Hz.  I'd recommend looking at the recordings that you've been playing.  I would guess that they largely have bass attenuation.  If you've got the equivalent of tone controls or upstream EQ, correct individual albums instead of cranking that into the loudspeakers all the time.  You can do that using miniDSP, but I'd name those EQ curves on your PC so that you know that you're boosting lows and attenuating highs.  If you find that you're using the boost and attenuation curves all the time, I strongly recommend demastering the albums that you're listening to--to remove the source of the problem at its source.  It should sound great when the Cornwalls are playing absolutely flat. 

 

By the way, I recommend changing the vertical resolution of the REW plots until the vertical scale lines are no more than 5 dB increments, with 2 dB being preferred, i.e.,

 

 

Chris

[pbphoto]

There was a survey done, or maybe I'm making this up, that it takes on-average 46 REW EQ curves before you get it right.  Only 45 more to go!  You start of tweaking the crap out of every little thing to get a flat curve, then you realize that sounds awful, and you ease back off until you apply the bare minimum of corrections, usually downward, to correct one or two big room problems and dial in your house sound.

[Chris A]

24 minutes ago, pbphoto said:

...and dial in your house sound.

I don't use "house curves"...of course.  I fix the problem at its source via demastering. 

 

27 minutes ago, pbphoto said:

There was a survey done, or maybe I'm making this up, that it takes on-average 46 REW EQ curves before you get it right.

Using REW's EQ facility, this is really collapsed down to about 2-3 sweeps/EQ updates. That's the real power of using REW to do EQ. 

 

The control of "how flat" is controlled via the flatness control within the EQ facility, and it generates PEQs based on that.  Once you get the flatness dialed in that generates a reasonable number of correcting PEQs, then you're ready to transfer those into your DSP crossover or upstream EQ function (it could be running on a computer acting as the player). 

 

Chris

[Emile]

34 minutes ago, pbphoto said:

it takes on-average 46 REW EQ curves before you get it right.  Only 45 more to go!  You start of tweaking the crap out of every little thing to get a flat curve, then you realize that sounds awful, and you ease back off until you apply the bare minimum of corrections, usually downward, to correct one or two big room problems and dial in your house sound

Haha ... yes; just learning ... 45 more to go.  Thanks!

[Emile]

1 hour ago, Chris A said:

That's a pretty big drooping down ramp starting at 2 kHz upwards.  That's more than 10 dB of droop on the high end.  If you're measuring on-axis at one metre, that droop should be limited to about 3 dB, not 10 dB.  That's a wee bit too much "house curve".

 

You're probably reacting to the fact that you've been listening to that big bass hump centered at 75 Hz.  I'd recommend looking at the recordings that you've been playing.  I would guess that they largely have bass attenuation.  If you've got the equivalent of tone controls or upstream EQ, correct individual albums instead of cranking that into the loudspeakers all the time.  You can do that using miniDSP, but I'd name those EQ curves on your PC so that you know that you're boosting lows and attenuating highs. 

Thanks @Chris A.   Thanks a lot for the advise.  Was measuring an equal triangle between my 2 speakers.   Yes; big drop of at the high end ... guess that is why it did not sound "dynamic" to me ... especially since I am used to KPT-904's   Was using Chuck Mangione's CD "feels so good" as a first test. (Probably a bit low end boosted.) Will try a better classical recording next.

Again my thanks!

Cheers, Emile

[Emile]

1 hour ago, Chris A said:

I strongly recommend demastering the albums

Yes; will try that ... but seems to have a steep learning curve