Venturing in REW + UMIK 1

[ankitbhargava]

After all the adjustments
gain addition on PB 2000 pro, applying PEQ at 40-60 Hz, level matching of subs with reference to other speakers, ... here is the Waterfall which stands as on 22nd September with and without MultiQT 32

With MultiQT reference



Without MultiQT32

 

[sud98]

Nice Progress.

Please use the time window of waterfall to 450ms and thats an area where you will have to use the minidsp PEQ settings for the room modes.

 

[RajithKumar]

Some more experiments,
today I gave more attention to the "basic setup" before measurement to fine tune settings I need in my MacBook for correct measurements.
This link was helpful :https://www.avsforum.com/threads/rew-for-macos-how-to-setup-your-mac-for-rew.3075106/

I learnt that this "basic setup" is VERY important, level matching by playing pink noise through REW is also VERY important.

Did a comparative of subwoofers response

Red line is "direct mode"
Green line is "AVR set to 7.1 channel"
**since there was a big dip in 45-55 Hz range, I just added some gain in PB 2000 pro to increase from "-18dbfs" to "-15dbfs"
Purple line is "after the gain applied and still no Audessey filter"
** added "-3db" more to PB 2000 pro
Orange line is after applying the "-3db" more gain to make it "-12dbfs"

All above without Audessey filters.

After this experiment, I played some go to scenes and the bass sounder more fuller, louder and also the LF effects were more impactful.

I frequently refer to scenes from John Wick 3 (john hitting hammer on floor", scene from "Arrival" where they are in Helicopter to take them to Alien site .. the helicopter blade blade rotation sound measures about 112 db and I still look for clarity as against muddy sound. I also refer to Dolby Atmos demo scenes from The Tomb Raider.

View attachment 49928

After above I also applied a PEQ on PB 2000 pro to pump up 50 hz and nearby frequencies (I know I should be more concerned about peaks than nulls) to try to boost the overall db in all frequency range of subs.

Result was even pleasant, I will share that curve toon next post.

Time spent brought me some conclusions
1. Audessey MultQT 32 was degrading the loudness the subs should show in scenes where subs need to hit 115db, though theoretically after applying MultQT 32 ... the FR is flatter but it takes away some fun of those sudden surges to "feel the base" and not only "hear it".
2. I have kind of understood where correctly to set the gain on sub and corresponding to that on AVR
3. Changing Phase of PB 2000 pro from "0" (PB 1000 is also on 0 )" to 90 made the bass more punchier and tight. I could hear that helicopter scene from "Arrival" on netflix .. the rotating blades sounded more tight and high db.
4. Achieving more db on Subs has made decay time and decay rate worst but somehow in real life I don't hear the sound degraded. Just to add, I am using a couple of Bass Traps and a lot of sound absorption panels.

Please advise if there is something terribly wrong with the approach.

I may fear to boost the null > 3db since the sub struggles sometimes and the head room may lost .I'm not 100% sure but I have seen some people do upto 6 db .Some experts can comment on this . IMO Its better to correct the null by proper placement,time alignment or by adding subs..

 

[alphacentury100]

I may fear to boost the null > 3db since the sub struggles sometimes and the head room may lost .I'm not 100% sure but I have seen some people do upto 6 db .Some experts can comment on this . IMO Its better to correct the null by proper placement,time alignment or by adding subs..

Yes, you are right. Upto 3db is fine but raising beyond that to compensate for the nulls will result in bottoming out.

 

[ankitbhargava]

I am using 3db boost through the SVS app, just to clarify again .. I am not using a Minidsp so far.

 

[RajithKumar]

Whatever tool,SVS app or minidsp take care while boosting a null.

 

[ankitbhargava]

Whatever tool,SVS app or minidsp take care while boosting a null.

sure

 

[MaSh]

I just dont bother with nulls at all. Just try to trim the peaks. Boosting nulls is just straining and wasting amp power in my opinion.

MaSh

 

[ankitbhargava]

I just dont bother with nulls at all. Just try to trim the peaks. Boosting nulls is just straining and wasting amp power in my opinion.

MaSh

I am trying to do some more experiments on weekend and definitely attempt this too. Shall share results on graphs and how it sounds differently in real life.

 

[DB1989]

I've been following this thread avidly as I'm also expecting my Umik to arrive any time now. Really excited at the possibilities since now I'll be able to compile some empirical data on my listening experiences

 

[RajithKumar]

Attaching my dual sub response in my room done with minidsp 2x4HD - Blue one is the Puredirect response after EQ with minidsp and Brown colour is after Audyssey over it.
Also attached Waterfall graph .
Expecting FM opinions on it.

 

[ankitbhargava]

Attaching my dual sub response in my room done with minidsp 2x4HD - Blue one is the Puredirect response after EQ with minidsp and Brown colour is after Audyssey over it.
Also attached Waterfall graph .
Expecting FM opinions on it.

Looks like MiniDsp has done a good job for you, what is this big at 67 Hz? crossover? sometimes if the other speakers aren't in phase with subs, there is a big dip around crossover.

 

[sud98]

Attaching my dual sub response in my room done with minidsp 2x4HD - Blue one is the Puredirect response after EQ with minidsp and Brown colour is after Audyssey over it.
Also attached Waterfall graph .
Expecting FM opinions on it.

Can you give your room dimensions and where the speakers/sub is located?

 

[RajithKumar]

Looks like MiniDsp has done a good job for you, what is this big at 67 Hz? crossover? sometimes if the other speakers aren't in phase with subs, there is a big dip around crossover.

I think it's because of room modes

 

[RajithKumar]

Can you give your room dimensions and where the speakers/sub is located?

Hi ! Room dimensions is 14.25' length x 10' width x 9.5' height.
Subs placed at mid wall ( length wise) faced each other .
Speakers configuration is Atmos/ dtsX 7.2.4 & Auro3d 10.2 .The Fronts are placed at around 25 degree from Listening position.
Seating distance around 10' from screen.

 

[RajithKumar]

Looks like MiniDsp has done a good job for you, what is this big at 67 Hz? crossover? sometimes if the other speakers aren't in phase with subs, there is a big dip around crossover.

It's only sub response ,so phase issue of speakers is not a concern .

 

[ankitbhargava]

One bad news
Its only been 2 weeks of usage of UMIK 1, today when I hooked it up to take some measurements ..the LED just dint turn up. UMIK stopped working. I tried different USB 2 cables but no, it doesn't work. Have raised concern to Avenue sound and also MiniDSP. It has one year manufacturer warranty but how bad! Have to go over pain of shipping it back and then waiting for replacement/repair.

 

[ankitbhargava]

I think it's because of room modes

I have a similar dip around 80

 

[rainbowsong2000]

All,

Venturing umik for the past 9 months and bought the MiniDSP 2x4 HD couple of weeks back. I am all new to the placement of subs... crossover...Phase etc etc... Thanks to @elangoas @RajithKumar, Raghu... and others helping me understand all the terms

So, for the past one week I was working like a crack... to make the curve straight (Ha ha) and I can achieve only this much.. leave it to experts comment. And it was challenging to make the Umik1 work with Rew and Asio4all time to time...(Now at least i know what's the problem and how to resolve it


My Room Dimension is 9' W X 18' L X 10' H, this is a master bedroom converted to dedicated HT, so the room has a big wardrobe on one side (Left Side and movement of Sub is little limited. After all the placement combination, found that diagonally opposite placement is the better one.

Here are some graphs i have achieved finally after 2 weeks of work with Umik1, Rew, Asio4All and Mini DSP 2x4 HD.

Front Right Subwoofer (SVS Pb2000)Pure Direct Mode and Without any Smoothing, just a raw measurement

Rear Left Subwoofer (SVS Pb2000) Pure Direct Mode and Without any Smoothing, just a raw measurement

Dual Subs (SVS Pb2000) Pure Direct Mode and Without any Smoothing, just a raw measurement (This big hump at 30hz cannot be reduce any further...)


Dual Subs (SVS Pb2000) Below is after eq and adjustment of eq in Mini DSP 2x4 HD without audessy


Dual Subs (SVS Pb2000) Below is after eq and adjustment of eq in Mini DSP 2x4 HD With Audessy. This is the best i can achieve




I followed this gentleman video in youtube... He is awesome... and the explanation was detailed.

 

[rainbowsong2000]

And this is the waterfall graph... Dont know what the heck is this... ha ha.... i guess the waterfall should be between 100 ms to max 300ms.

But here at 15hz, 30hz and 50hz the waterfall is breaking the bank

OK Final Experience....

All the bass responses are very smooth... i dont know much of the sound jargans.. so.. in layman terms...

Earlier, the low rumbling were too much and some times little irritating and there will not be a chest slamming bhams ... but now.. all over response is very smooth and i am not getting any big room rattling irritation.. and the high impact scenes are very good... say Johnwick gunshots... Benghazi fight scenes and Alita robot walking in the road... those are all wow...

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