Hifi - How to Record Review EQ - In your Room - Workflow

0 Members and 1 Guest are viewing this topic. Read 463 times.

penguinpages

  • Jr. Member
  • Posts: 28
  • penguinpages

I have over the last year purchased, and built speakers from GRResearch.  Built a Dynaco ST120 Tube Amp.  Treated room, purchase UMik-1 calibrated mic.  And tried to do final "room tuning" via various YouTube Videos.   Then upload correction file to my MiniDSP Flex.

But I think the peice of that process that I am least confident in my doing correctly is the process to room correct, know what I am looking at and deciding if its "good" or ok... or.. well.. need more investment.   To make any more investment, I first need to walk through sufficient review of what I have to create a more "critical" baseline.   Not just "it sounds good to me" but also, what do measurements show.


Ask:
Can someone help, and or point me to existing posting where someone does walk through of how they "do speaker measurements in a room.

What I would love to see, is someone like Danny or someone of that "industry experience,  Define and maybe even post in segments a set of videos of "how I would ..."   Like if they were to be asked by their friend. ... who purchased all there recommended speakers...  room EQ.

Process:
1) Prep room and speaker placement. I think is already well covered:  https://www.youtube.com/watch?v=CyTkwkK8ON0
2) How to record room sweeps and create baseline recording: This is a bit old but what I have found that is comprehensive https://www.youtube.com/watch?v=Ev1bSSL8tRA
          a) Tools to use:  REW, Calibrated mic, House Curve File ?
          b) How to setup tools and run them  Ex: When Danny does review of speaker... he does X Y X and formats and etc... so you can follow along in your room
3) How to read those file and decision tree of "what I would do"..... <this is missing>
          a) What is "great speaker / room" look like where there is just minimal tweaking, as a baseline
          b) What is a "needs work and how" example, where bones of speaker / amp / eq are good, but you see issues and can use tools to adjust.
          c) How you would review to make statement like "this system in its current room constrains, could take advantage of X upgrade.
4) How to apply them to DSP. This is very device specific, but maybe a few popular samples will provide reference:  Best one I found so far  https://www.youtube.com/watch?v=366-thzDpI8   But this is focused on Movie / AV not Hifi


Maybe this has been done and is posted somewhere i have not found.
I am game to use my setup /room as Guinee pig but before I banter on forum, maybe someone has other parts of above already documented I can RTFM first.


Ex: Two attached images.  I think I have correctly collected data but it is not in same format I see Danny review speakers.. so I can't tell if this is "good"... or.. something is BAD.


This is average scans: Head Center, then +/- 6" each direction



This is waterfall view.  But I don't think I have some setting of scale set correct to be able to know if this is good or bad.









WGH

Re: Hifi - How to Record Review EQ - In your Room - Workflow
« Reply #1 on: 30 Dec 2023, 06:38 pm »
You mention you treated the room. What did you use and where? You can measure until the cows come home but if the treatment is wrong the measurements will be wrong.

What GR Research speakers did you build? You don't have to do too much to make them sound good.


A/V Room Service has a lot of free articles about room treatment which will get you started.
https://avroomservice.com/articles/


Stereophile has an excellent technical article about reflected sound and absorption. Basically what everyone has been doing for years is wrong.

NWAA Labs: Measurement Beyond The Atomic Level
https://www.stereophile.com/content/nwaa-labs-measurement-beyond-atomic-level


The scans look great but the broad dip around 40 Hz can't/shouldn't be corrected with DSP, that's what a subwoofer is for.

jmimac351

  • Full Member
  • Posts: 335
  • Chief Instructor - ChinTrackDays.com
Re: Hifi - How to Record Review EQ - In your Room - Workflow
« Reply #2 on: 30 Dec 2023, 08:07 pm »
You mention you treated the room. What did you use and where? You can measure until the cows come home but if the treatment is wrong the measurements will be wrong.

What GR Research speakers did you build? You don't have to do too much to make them sound good.


A/V Room Service has a lot of free articles about room treatment which will get you started.
https://avroomservice.com/articles/


Stereophile has an excellent technical article about reflected sound and absorption. Basically what everyone has been doing for years is wrong.

NWAA Labs: Measurement Beyond The Atomic Level
https://www.stereophile.com/content/nwaa-labs-measurement-beyond-atomic-level


The scans look great but the broad dip around 40 Hz can't/shouldn't be corrected with DSP, that's what a subwoofer is for.


Thank you so much for sharing this!!!  :thumb:






penguinpages

  • Jr. Member
  • Posts: 28
  • penguinpages
Re: Hifi - How to Record Review EQ - In your Room - Workflow
« Reply #3 on: 30 Dec 2023, 09:58 pm »

Thanks for the response.  I think I have room treatment down.   Below is "Pano" picture of room (me in corner)...  Rear has one panel ,  Couch, and table and desk (room is 11'6" x 16' x 7'10" and was one of the components I tried to define in REW).

The walls are made of Rockwool 1 1/2" x 12" x 7' with soft cloth cover.
Ceiling is coffered with the old "4' x 8' drop ceiling tiles doubled up , glued together to make a mat and set on top of grid and then layer of rockwool on top of that (mostly so wife does not hunt me down when I am playing music at night :)
Floor has a plush rug.
Rear wall is three layers of felt and one of cloth.

I am sure everyone has "issues" with limitations on treatment or layout or design, or compromises had to be made.   But that is real life and living and so this topic is more about how to measure and tune... then room treatment, but as noted, this is fundamental to the total topic of measurement and doing the best with what you have.

My room issues:
1) I cannot move speakers (X-MTM Encore Kit, and two Servo Sealed Kit and Flatpack) out into room.  They are pushed back up close to the wall and that is why I put ports out front (though that may have been a major / stupid mistake)... originally I thought my wife would have forced me to push right up against wall and not treat back wall.. so I built with front port as compromise.. but now.. I can I think fix that and either remake the boxes, or restructure ports back out rear . but... that is one reason I want to work out measurements... is this needed?

2) Room size.  11' x 16' and I have to have couch, (movie room also) and my office (desk , monitors, chair) .. this is where I spend 80% of my life (wife tosses cookies down stairs to basement for me if she is feeling nice). 

3) Air Vents: I built custom ducts of Fiber board, into room that I can shut off with soft hatch.  This cuts down on wind sound also allowing me to seal room more for playing at night / loud.





As for other design constrain: $$

I made my own Dynaco ST120 with upgrades   https://dynacotubeaudio.forumotion.com/t5087-st-120-dual-rectifier-upgrade  but that means I am power limited.  Hense my design was to pair a MTM with a Servo for each side





 and I have crossover set to take heavy load (low end) off the Tube Amp / MTM and put on Servo.




That is foundation where I started REW / room recording / tuning.   

You are correct that these fundamentals are important.  But "A$$uming" those are done... "now what" / WWDD (What Would Danny Do).. or other such HiFi nerd.

Goal
1) Discover and document current settings
2) Tune room if / as needed (phasing, sound issues , like dip noted)
3) Asses if it is mapping close enough to "what it should be doing" such that maybe investing in X or Y upgrade would be worth it.. or.. due to room or other contrains, its never going to be noticed as its lost in other design limiations.


As always, thanks for response.










Hafgrim

  • Jr. Member
  • Posts: 37
Re: Hifi - How to Record Review EQ - In your Room - Workflow
« Reply #4 on: 1 Jan 2024, 03:12 am »
It's a lot of work to learn room acustics.
Here is a good tutorial on rew and what those graphs mean.
https://youtu.be/HYMQ6M-Z5rM?si=0LCgf9J3N-2rZ6Qe
https://youtu.be/CuEwoeN7ZJk?si=Y-THJnaxMkAO7mB9

After that watch as many videos on the channel Acoustics Insider
https://youtu.be/IFNaBc4PUNI?si=D_JBQIbgE3WY9KmE

These guys are primarily about studio acoustics but the its the same things.