Author Topic: REW questions  (Read 28320 times)

Offline ronildoq

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Re: REW questions
« Reply #30 on: January 21, 2017, 15:52 »
I am also ready to make the commitment to try learning REW myself. Too bad there is no sticky thread here in XP to ease less technically/mathematically inclined guys like myself into it  :-[

Nevertheless, I would like to join in any mass order purchase for the Cross Spectrum Labs Umik-1 mic and SPL meter to lessen our overall shipping costs.

http://www.cross-spectrum.com/index.html

Also thinking of getting this budget tripod for the umik and spl meter

https://www.aliexpress.com/item/Top-Sell-Portable-Professional-Aluminum-Telescopic-Camera-Tripod-Stand-Holder-For-Smart-Phone-For-iPhone-For/32622915038.html?spm=2114.13010208.99999999.264.trIYNd

Okie now to search for some basic guides to REW...

Bro the tripod screws are different, won't fit with the umik 1, get the clip type would be better, Can hold onto any microphone firm and ability to tilt 90degrees or front firing


Offline Jag

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Re: REW questions
« Reply #31 on: January 21, 2017, 16:56 »
Center bass management seems unusual. Center only FR shouldn't have bass response at 30hz. This tells me either bass management malfunctioning , or measurement is readings are incorrect.

I will have a closer look at the REW MDAT files later.

I expect little to no spls below 50hz. That's what's bass management is supposed to do. To redirect bass to subs only so that cancellations between mains and subs are minimised.
Electronics : Denon 7200, MiniDSP Dirac 88A, Emotiva XPA-5 Gen2
ATMOS Audio : Martin Logan Ethos (L&R), ML Motif X(C), ML Motion 4 (14pcs surround spkrs)
LFE : Dual Rythmik FV25HP & Crowson Motion Actuator
Video : Sony VPL-HW55ES, Stewart Screen Studiotek 1.3
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Offline whyeme

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Re: REW questions
« Reply #32 on: January 21, 2017, 19:02 »
Bro the tripod screws are different, won't fit with the umik 1, get the clip type would be better, Can hold onto any microphone firm and ability to tilt 90degrees or front firing

Thks for pointing this out bro but I saw that this tripod has an attachment for smartphones too so was hoping can use for umik and spl meters too :)
Hall: Philips 65PFA4350/98. Oppo BDT-101CI. Emotiva UMC-200. Rotel RMB-1512. SB Acoustics ARA. Dynaudio Contour SCX. Dynaudio Audience 42. Wharfedale 10.1. PSA XS30. Orisun DD+12. miniDSP Dirac DDRC-88A/BM. Belden Studio 814. IsoAcoustics ISO-L8R155. Zidoo H6 Pro.

Bedroom: Plinius 2100i. Dynaudio Excite X12. iFi Micro iDSD. Plixir Bac 1200. IsoAcoustics ISO-L8R155. Belden Studio 814.

Offline whitesox

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Re: REW questions
« Reply #33 on: January 21, 2017, 21:12 »
Center bass management seems unusual. Center only FR shouldn't have bass response at 30hz. This tells me either bass management malfunctioning , or measurement is readings are incorrect.

I will have a closer look at the REW MDAT files later.

I expect little to no spls below 50hz. That's what's bass management is supposed to do. To redirect bass to subs only so that cancellations between mains and subs are minimised.

Yes bro...
Seems higher Xover for my C sounds more reasonable so sub will take wider control
Waiting for your guidance...
 :)

Offline whitesox

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Re: REW questions
« Reply #34 on: January 21, 2017, 21:16 »
Thks for pointing this out bro but I saw that this tripod has an attachment for smartphones too so was hoping can use for umik and spl meters too :)
Bro,
Tripod usually used for digital camera that's why it uses smaller diameter than diameter of umik.
By just look at it, I know already... couldn't fit.
 
You wont be able to screw in...

« Last Edit: January 21, 2017, 22:18 by whitesox »

Offline ronildoq

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Re: REW questions
« Reply #35 on: January 21, 2017, 21:38 »
Center bass management seems unusual. Center only FR shouldn't have bass response at 30hz. This tells me either bass management malfunctioning , or measurement is readings are incorrect.

I will have a closer look at the REW MDAT files later.

I expect little to no spls below 50hz. That's what's bass management is supposed to do. To redirect bass to subs only so that cancellations between mains and subs are minimised.


Yea, now I recall, I think the avr set the Centres to 40hz or was it full range after audy measurement , probably forgot to change the cross over to 80hz when we measured centre only, that explains why the centre has not rolled off after 60/ 80hz cross over.

I think bro whitesox will have to remeasure crossing over centre channel only from 60-100hz then post his graph here for further analysis picking best crossover .

Having said that, that wouldn't change the fact that using 60,70,80 crossover with subs would still result in a dip in the crossover range...

The solution to solving the dip would be? Crossing over at a higher point ? 90/100hz? Since the subs r flat to 100hz
Or go with distance tweaking subs?

I experienced a similar case with whitesox. Crossing over at 90hz at my home, solved the dip in the crossover region, having it at 60-80, I had a minor dip. After listening for 2 weeks, i found 60hz to be way nicer. I then went distance tweak for delays to integrate both c and subs at 60hz.

Offline whitesox

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Re: REW questions
« Reply #36 on: January 21, 2017, 22:23 »
Bro Jag/Roni,
Instead of just look at a dip at 82hz (X-axis), I wonder whether do we need to look at Y-axis (db)?



Referring to purple graph - distance/delay given by Audy:
Is 71db dip at 82hz that consider bad ? how about after 140hz? is it normal having so many dips there?
« Last Edit: January 21, 2017, 22:31 by whitesox »

Offline sevenz

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Re: REW questions
« Reply #37 on: January 21, 2017, 22:34 »
Is 71db dip at 82hz that consider bad (refer to purple graph - distance/delay given by Audy) ? how about after 140hz? is it normal having so many dips there?



Yes your 82hz dip is bad bro.

U see, your FR is about 85-87db level from 40hz - 100hz.

But at 82hz, it swing from 85-87db down to 71db. 15db volume difference bro! Means to hear the same bass volume at 82hz, u need to turn your volume up +15db to hear the same volume level. Imagine how much difference in volume that is on your AVR.

If u run a continuous test tone from 0hz to 100hz, suddenly your 82hz bass will become very soft,  15db less than your 40-70hz, 90-100hz
« Last Edit: January 21, 2017, 22:37 by sevenz »

Offline whyeme

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Re: REW questions
« Reply #38 on: January 21, 2017, 22:54 »
Bro,
Tripod usually used for digital camera that's why it uses smaller diameter than diameter of umik.
By just look at it, I know already... couldn't fit.
 
You wont be able to screw in...



roger that...will look for the kiap kiap kind...thks
Hall: Philips 65PFA4350/98. Oppo BDT-101CI. Emotiva UMC-200. Rotel RMB-1512. SB Acoustics ARA. Dynaudio Contour SCX. Dynaudio Audience 42. Wharfedale 10.1. PSA XS30. Orisun DD+12. miniDSP Dirac DDRC-88A/BM. Belden Studio 814. IsoAcoustics ISO-L8R155. Zidoo H6 Pro.

Bedroom: Plinius 2100i. Dynaudio Excite X12. iFi Micro iDSD. Plixir Bac 1200. IsoAcoustics ISO-L8R155. Belden Studio 814.

Offline Jag

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Re: REW questions
« Reply #39 on: January 22, 2017, 21:52 »

Yea, now I recall, I think the avr set the Centres to 40hz or was it full range after audy measurement , probably forgot to change the cross over to 80hz when we measured centre only, that explains why the centre has not rolled off after 60/ 80hz cross over.

I think bro whitesox will have to remeasure crossing over centre channel only from 60-100hz then post his graph here for further analysis picking best crossover .

Having said that, that wouldn't change the fact that using 60,70,80 crossover with subs would still result in a dip in the crossover range...

The solution to solving the dip would be? Crossing over at a higher point ? 90/100hz? Since the subs r flat to 100hz
Or go with distance tweaking subs?

I experienced a similar case with whitesox. Crossing over at 90hz at my home, solved the dip in the crossover region, having it at 60-80, I had a minor dip. After listening for 2 weeks, i found 60hz to be way nicer. I then went distance tweak for delays to integrate both c and subs at 60hz.


If I were in whitesox shoes, this is what I would do.

1) the dip at 85hz is a result of center and subs cancelling out each other.
2) I would measure center speaker without subs, set cross over to just slightly above 85hz. Re-measure to verify cross-over is set correctly for the center.
3) measure each sub independently to understand which freq of each sub is deficient at.
4) measure FR for A+B subs to ensure minimal destructive cancellation. Repeat until all subs are measured with minimal cancellations in FR?
5) measure C+subs, with interest at cross over freq. we want the FR to add up.if they are cancelling, I would invert phase or distance until they add up.

If you wish, I can help to measure and give some further advise to maximize your equipment potential.
Electronics : Denon 7200, MiniDSP Dirac 88A, Emotiva XPA-5 Gen2
ATMOS Audio : Martin Logan Ethos (L&R), ML Motif X(C), ML Motion 4 (14pcs surround spkrs)
LFE : Dual Rythmik FV25HP & Crowson Motion Actuator
Video : Sony VPL-HW55ES, Stewart Screen Studiotek 1.3
Source : HTPC
Fully automated HT via Alexa, Z-wave and Logitech Harmony Remote Control

Offline gluttony

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Re: REW questions
« Reply #40 on: January 22, 2017, 22:08 »
the problem is whitesox does not want to invest a umik mic else he can remeasure

Offline Jag

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Re: REW questions
« Reply #41 on: January 22, 2017, 22:45 »
Then just continue knowing there are are issues unresolved. Not getting optimum results after spending so much money on top equipment..... need to do justice to $ and equipment spent.
Electronics : Denon 7200, MiniDSP Dirac 88A, Emotiva XPA-5 Gen2
ATMOS Audio : Martin Logan Ethos (L&R), ML Motif X(C), ML Motion 4 (14pcs surround spkrs)
LFE : Dual Rythmik FV25HP & Crowson Motion Actuator
Video : Sony VPL-HW55ES, Stewart Screen Studiotek 1.3
Source : HTPC
Fully automated HT via Alexa, Z-wave and Logitech Harmony Remote Control

Offline ronildoq

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Re: REW questions
« Reply #42 on: January 22, 2017, 23:24 »
I think he is in the process of getting the mic. Too bad I couldn't finish the measurement having spent too much time on finding best placement for subs and phase aligning them. Only left with integration of c with subs, pretty sure 90hz cross over should solve the dip.....but still need to measure to confirm this.

I've advised  whitesox to read up and play around with REW first. Then when sifu jag helps, u will know the right questions to ask, can learn from there. That is how I learn too... REW is really powerful, I've gained a lot measuring and experiencing and listening...

Jag is always so kind to help...

Offline Jag

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Re: REW questions
« Reply #43 on: January 23, 2017, 08:30 »
The best way to learn REW is to play around with it on your own first. When I swing by, your questions will help your learning far better than I teaching from scratch.

As Ronildoq has mentioned, it takes some time to find best sub placement, crawling around, Audyssey, PEQ and speaker settings to achieve max performance from every $ spent on our HT. But once there, your HT will never be the same anymore.
Electronics : Denon 7200, MiniDSP Dirac 88A, Emotiva XPA-5 Gen2
ATMOS Audio : Martin Logan Ethos (L&R), ML Motif X(C), ML Motion 4 (14pcs surround spkrs)
LFE : Dual Rythmik FV25HP & Crowson Motion Actuator
Video : Sony VPL-HW55ES, Stewart Screen Studiotek 1.3
Source : HTPC
Fully automated HT via Alexa, Z-wave and Logitech Harmony Remote Control

Offline whitesox

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Re: REW questions
« Reply #44 on: January 23, 2017, 09:15 »
the problem is whitesox does not want to invest a umik mic else he can remeasure

Don't judge me so fast bro...  ;D


I think he is in the process of getting the mic. Too bad I couldn't finish the measurement having spent too much time on finding best placement for subs and phase aligning them. Only left with integration of c with subs, pretty sure 90hz cross over should solve the dip.....but still need to measure to confirm this.

I've advised  whitesox to read up and play around with REW first. Then when sifu jag helps, u will know the right questions to ask, can learn from there. That is how I learn too... REW is really powerful, I've gained a lot measuring and experiencing and listening...

Jag is always so kind to help...

Bro Roni knows me better than you
« Last Edit: January 23, 2017, 09:16 by whitesox »