ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [All]   Go Down

Author Topic: True Auto-EQ. Please Tell Me If This Already Exists Or Why It's Impossible!  (Read 4916 times)

Steve Cruz

  • Newbie
  • *
  • Offline Offline
  • Posts: 3

I've often wondered why there's not an analyzer/EQ that could compare any pre-recorded music with a measurement mic of the signal in the room, and then automatically eq the system to match (or, more realistically, get in the ballpark of) the original signal.

It would need inputs for the stereo program, (with a loop thru to the mixer inputs), a measurement mic input, and stereo I/O for the EQ.

The obvious advantage would be playing music during the pre-show, as the room fills up, and the system automatically adjusting to the changes in the room sound.

Is it out there somewhere already?

Is it a pipe dream?

Steve Cruz
Logged

Mark McFarlane

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1865
  • Middle East
    • Arkose Records

Not automatic, but one could use Smart to capture a trace at the start of the show, and use that to adjust EQ manually later in the day.
Logged
Mark McFarlane
ARKOSERECORDS
Turn down what's too loud.

Merlijn van Veen

  • Moderator
  • Sr. Member
  • *****
  • Offline Offline
  • Posts: 309
    • www.merlijnvanveen.nl

I've often wondered why there's not an analyzer/EQ that could compare any pre-recorded music with a measurement mic of the signal in the room, and then automatically eq the system to match (or, more realistically, get in the ballpark of) the original signal.

It would need inputs for the stereo program, (with a loop thru to the mixer inputs), a measurement mic input, and stereo I/O for the EQ.

The obvious advantage would be playing music during the pre-show, as the room fills up, and the system automatically adjusting to the changes in the room sound.

Is it out there somewhere already?

Is it a pipe dream?

Steve Cruz

Hi Steve,

Data without context is meaningless. IMHO a computer will not likely be able to interpret raw data like humans do based on expectations, reasoning and experience.

In the medical world computers are used to make MRI and X-rays scans but it takes a radiologist to draw the final conclusion.

Regards,

Merlijn

John Roberts {JR}

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 16550
  • Hickory, Mississippi, USA
    • Resotune

I've often wondered why there's not an analyzer/EQ that could compare any pre-recorded music with a measurement mic of the signal in the room, and then automatically eq the system to match (or, more realistically, get in the ballpark of) the original signal.

It would need inputs for the stereo program, (with a loop thru to the mixer inputs), a measurement mic input, and stereo I/O for the EQ.

The obvious advantage would be playing music during the pre-show, as the room fills up, and the system automatically adjusting to the changes in the room sound.

Is it out there somewhere already?

Is it a pipe dream?

Steve Cruz
Automatic EQ has been around so long it's old... But they don't use music for the source to compare, but a wide band noise source to check the entire bandpass.

Flat wide band noise is annoying to listen to so generally this is not done in front of an audience. Also to prevent errors due to microphone placement interaction with room modes or boundaries, multiple mics are used, or one mic is sampled and moved around the room.

Pre-recorded music could probably be used as a source with modern technology that first measures the source spectrum then the playback return spectrum. If it's a large room with multiple speakers, transit time or arrival delay would have to be factored in. A dual channel spectrum analyzer with simple math functions should be capable of comparing the return frequency response to the source frequency response. Error requiring EQ correction would show up +/-.

Of course audience noise would look like response that needs to be cut, and the audience presence would influence the room response due to absorption.
 
JR

 

Logged
Don't tune your drums half-ass. Listen to what a properly "cleared" drum sounds like.   http://circularscience.com/

John Chiara

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1148

Automatic EQ has been around so long it's old... But they don't use music for the source to compare, but a wide band noise source to check the entire bandpass.

Flat wide band noise is annoying to listen to so generally this is not done in front of an audience. Also to prevent errors due to microphone placement interaction with room modes or boundaries, multiple mics are used, or one mic is sampled and moved around the room.

Pre-recorded music could probably be used as a source with modern technology that first measures the source spectrum then the playback return spectrum. If it's a large room with multiple speakers, transit time or arrival delay would have to be factored in. A dual channel spectrum analyzer with simple math functions should be capable of comparing the return frequency response to the source frequency response. Error requiring EQ correction would show up +/-.

Of course audience noise would look like response that needs to be cut, and the audience presence would influence the room response due to absorption.
 
JR

What John said. Just have the spend time and learn.
Logged

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 9030
  • Atlanta GA

One of the big problems with an "automatic" system is that it can tend to "do some really bad things" to the signal going to the speakers in order for the process to "appear" to be correct.

Just because something is called "automatic" does not that it is.

Take your car for example. Does it have a "automatic" transmission in it?

I don't care WHAT the manufacturer say-IT DOES NOT!!!!!!!!!!!

I have never seen a car that you simply start it up and it "automatically" knows whether to go into drive or reverse.

When you stop somewhere-does it "automatically" go into park?

It DOES require knowledgable  human intervention in order to operate properly.

Yes it changes gears automatically-but it does not do everything automatically.

Just sayin----------
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

Luke Geis

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2072
    • Owner of Endever Music Production's

From a broad band perspective, I could see an algorithm that could make pink noise follow a defined curve. With music however there is no way you could make an algorithm that could distinguish between the different EQ and timbre aspects of all the instruments to make a similar sound to your desired media of choice. In other words if the guitar has a sharp mid range and too much high end is rolled off, the Auto Compensator will bring that mid range down to match the control media. This means that everything at those frequencies will also come down with it. So it could at best only average out all the instruments to acquire the desired EQ curve, but not able to sonically match each instrument.

Now if your into heavy processing and are fully digital and don't mind a little latency I could see a variation of that concept. Instead of desired House EQ curve why not do that to each track. This would require a band to have a multi track recording and DAW that has used the original multi track recording to acquire the EQ curve of each instrument. This EQ curve would then be saved per channel as a reference and the program ( a multi channel DAW software ) would EQ each channel streamed in from the mixer to match the reference EQ. This would allow for song to song control and the FX could probably also be routed through with automation? In essence your would be running a S.A.C system, but latency would be higher due to multiple instances of processing on many channels. You could then EQ the house PA to match the the mastered version of the songs EQ response. It won't be exact, but it would be closer.
Logged
I don't understand how you can't hear yourself

g'bye, Dick Rees

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7424
  • Duluth

I've often wondered why there's not an analyzer/EQ that could compare any pre-recorded music with a measurement mic of the signal in the room, and then automatically eq the system to match (or, more realistically, get in the ballpark of) the original signal.

It would need inputs for the stereo program, (with a loop thru to the mixer inputs), a measurement mic input, and stereo I/O for the EQ.

The obvious advantage would be playing music during the pre-show, as the room fills up, and the system automatically adjusting to the changes in the room sound.

Is it out there somewhere already?

Is it a pipe dream?

Steve Cruz

Depends on what you're smokin'...
Logged
Pay no attention to the man behind the curtain...

David Sturzenbecher

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1705
  • So. Dak.
    • Sturz Audio




When you stop somewhere-does it "automatically" go into park?



My last rental automatically turned itself off when I stopped... Then started itself back up when I pressed the gas.   Really annoying.


Sent from my iPhone using Tapatalk
Logged
Audio Systems Design Engineer
Daktronics, Inc.
CTS-D, CTS-I
AES Full Member

Mark McFarlane

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1865
  • Middle East
    • Arkose Records

My last rental automatically turned itself off when I stopped... Then started itself back up when I pressed the gas.   Really annoying.


Sent from my iPhone using Tapatalk
What kind of car?  Electric? hybrid?  That would seem odd, especially in my 25 year old Landcruiser that takes a few cranks to get going,...
Logged
Mark McFarlane
ARKOSERECORDS
Turn down what's too loud.

Chris Tsanjoures

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 65

Data without context is meaningless. IMHO a computer will not likely be able to interpret raw data like humans do based on expectations, reasoning and experience.

In the medical world computers are used to make MRI and X-rays scans but it takes a radiologist to draw the final conclusion.

Regards,

Merlijn

yes x1000
Logged
I am employed by Rational Acoustics. Besides being a Product Manager for the Smaart Platform, I operate as a fully deployable Smaart Ninja (aka Instructor/System Guy).

ProSoundWeb Community


Pages: 1 2 [All]   Go Up
 



Page created in 0.049 seconds with 25 queries.