# REW or Dirac Live: which tells the truth?



## FargateOne (Mar 3, 2015)

I would really know if it is something that I must worry about or if it is not important but maybe have I posted my question in the wrong section. So I copy the link here.

http://www.hometheatershack.com/forums/rew-forum/143666-rew-dirac-live-tells-truth.html


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## KelvinS1965 (Feb 6, 2011)

I've compared a single point Dirac calibration against a REW measurement (without moving the mic) and they were pretty much identical. However, if you take a 9 point Dirac calibration, then try to 'check' it using REW at the MLP, then you won't get the same result.

Additionally; I've found that the REW room sim matches pretty closely to what I measure in room with REW as well. It's a great tool and one that is getting plenty of use planing my new room and helping me work out (starting points) for the speaker and 8 subs positions.


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## FargateOne (Mar 3, 2015)

KelvinS1965 said:


> I've compared a single point Dirac calibration against a REW measurement (without moving the mic) and they were pretty much identical. However, if you take a 9 point Dirac calibration, then try to 'check' it using REW at the MLP, then you won't get the same result.
> 
> Additionally; I've found that the REW room sim matches pretty closely to what I measure in room with REW as well. It's a great tool and one that is getting plenty of use planing my new room and helping me work out (starting points) for the speaker and 8 subs positions.


Thank you very much to have taken the time to answer to my post. But my question was related to a problem that I had and now maybe solved. The signal from the right channel was different between Dirac and Rew. Weeks later, it appears that my bd player was a bad unit. The company refunds my money. I have a new one since a few days. I want to listen my system "as is" for a while because to many changes and problems in a short period of time confuse me. In a couple of weeks maybe I will put nanovr-dl again in the chain to see if the problem is really solved. 

About your comment, I agree with you. In order to compare Rew and Dirac, a single point measurement is the only option.


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## KelvinS1965 (Feb 6, 2011)

Sorry I see that I answered the wrong question (or rather I should have read more of your link). It does seem a strange problem, I hope your new player solves the issue. 

Since I have the DDRC-88A I guess it's a different process to inject the REW test tones to your miniDSP Nano? In my case I just have to connect my laptop to a spare input on my AVR and select either stereo or Prologic (depending if I want to measure LR+subs or Centre+subs). My AVR then does the bass management _before_ the '88A (though I may take up the new option to upgrade the 88A with new software to allow it to perform BM instead). The AVR then just controls the signal level to the speakers and sub(s) with all the speaker distances/levels set to 0 as the 88A is doing the delays and level matching.

With the nanoDL do you have to use a disc to play back test tones for REW, or just connect your laptop to the HDMI input perhaps? I'm thinking that if it's the later then I can't understand why the player would affect the result with REW.

I realise you've probably solved the issue now, but just trying to understand what caused it out of academic interest.


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## FargateOne (Mar 3, 2015)

KelvinS1965 said:


> Sorry I see that I answered the wrong question (or rather I should have read more of your link). It does seem a strange problem, I hope your new player solves the issue.
> 
> (...)
> With the nanoDL do you have to use a disc to play back test tones for REW, or just connect your laptop to the HDMI input perhaps? I'm thinking that if it's the later then I can't understand why the player would affect the result with REW.
> ...


Thank for your interst in my case; this can help somebody one day.

Again you are right about test tones with Rew and nanoavr-dl, the laptop was connected to NanoAvr-dl via the second hdmi input ( no disc needed). And your thoughts are exactly mines: why on earth, if the problem was upstream from the bd palyer, does Dirac get it but not Rew. My guess is since Nano needs the video signal to put the filters in the audio path in the hdmi, the video from the laptop did not send a" bad" video signal. The broken part of the faulty bdplayer was maybe mechanical or related to the laser into it and for a mysterous reason was affecting the right channel only!!:huh::dizzy::scratchhead::surrender:. I am not sure that a new player will solve my problem. It is why, later if I find the courage, I intend to try NanoAvr-dl again and see...

BTW there is a storm in an other forum between those who think that EQuing before bass management is an heresy. According to this, your setting would be better.


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## KelvinS1965 (Feb 6, 2011)

Yes, I've heard arguments against doing BM after eqing, but since you already have your nanoDL and I have the '88A then I guess we both have to use what we have regardless of the arguments. 

There will be an update (I'm sure there will be a cost involved) to add bass management to the '88 via a software update, so you have to wonder where that sits regarding BM after eqing.

Hope your new player works out fine, plus I hope you can get the nanoDL working to your satisfaction: I'm so pleased with Dirac compared to my previous XT32 set up (which always sounded too harsh to my ears), plus I love that I can tweak target curves to really get the result I like especially when blending the subs and satellite speakers.


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## FargateOne (Mar 3, 2015)

KelvinS1965 said:


> Yes, I've heard arguments against doing BM after eqing, but since you already have your nanoDL and I have the '88A then I guess we both have to use what we have regardless of the arguments.
> 
> There will be an update (I'm sure there will be a cost involved) to add bass management to the '88 via a software update, so you have to wonder where that sits regarding BM after eqing.
> 
> Hope your new player works out fine, plus I hope you can get the nanoDL working to your satisfaction: I'm so pleased with Dirac compared to my previous XT32 set up (which always sounded too harsh to my ears), plus I love that I can tweak target curves to really get the result I like especially when blending the subs and satellite speakers.


Kelvin,
I give you an update and I confirm that the problem, as bizarr it is, was UPSTREAM !!
I made my first Dirac measurement today with a the n CAmbridge CXU i bought 3 months ago, and NanoAvr-DL and Dirac seems to work well.


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