Galaxy CM-140 Calibration File Info Thread - Page 2 - Home Theater Forum and Systems - HomeTheaterShack.com
Reply
 
Thread Tools
post #11 of 45 Old 03-10-07, 06:41 PM Thread Starter
Elite Shackster
 
Sonnie's Avatar
 
Join Date: Apr 2006
Location: L.A. (Lower Alabama)
Posts: 22,577
My System
Re: Galaxy CM-140 Calibration File Info Thread

It is my honor to do so... I want nothing less than as good as I can provide for everyone...
Sonnie is offline  
Sponsored Links
Advertisement
 
post #12 of 45 Old 03-13-07, 11:17 AM
Pending
Eric
 
Join Date: Jun 2006
Location: Lindenhurst, IL
Posts: 1
Re: Galaxy CM-140 Calibration File Info Thread

Quote:
Sonnie wrote: View Post
Secondly and most assuredly something that will excite several of you... my ECM8000 is going to be calibrated down to at least 5Hz. Once it is returned, I will hopefully be able to provide you with a calibration file to 5Hz or lower for the CM-140.
This is awesome Sonnie. Thanks much for doing this! Can't wait to get it and put it to use.

Eric
Eric_RP is offline  
post #13 of 45 Old 03-15-07, 01:24 PM
Shackster
Ivan
 
Join Date: Feb 2007
Location: DFW, Texas
Posts: 10
Re: Galaxy CM-140 Calibration File Info Thread

Thanks Sonnie !!

Last edited by ifeliciano; 03-15-07 at 11:46 PM.
ifeliciano is offline  
 
post #14 of 45 Old 03-16-07, 12:41 PM
Shackster
jim
 
Join Date: Dec 2006
Location: Scarborough Maine
Posts: 26
Re: Galaxy CM-140 Calibration File Info Thread

Are you having the high end done, and above 8khz? Now I think I should have bought a 140 instead of getting my RS charted...Jim
nerdful1 is offline  
post #15 of 45 Old 03-16-07, 01:05 PM Thread Starter
Elite Shackster
 
Sonnie's Avatar
 
Join Date: Apr 2006
Location: L.A. (Lower Alabama)
Posts: 22,577
My System
Re: Galaxy CM-140 Calibration File Info Thread

The initial plans are to provide a calibration file for the bass region. I will provide some measurements full range, but I'm not sure anyone is going to be up to the task to complete a calibration file for it. It would be a fairly gruesome task IMO.
Sonnie is offline  
post #16 of 45 Old 03-16-07, 01:27 PM
Senior Shackster
 
Vader's Avatar
Derek
 
Join Date: Jul 2006
Location: Colorado
Posts: 402
My System
Re: Galaxy CM-140 Calibration File Info Thread

Sonnie,

I have always read that the Rat Shack meter is 2 to 3 dB low when using the pink noise on DVE to calibrate (ie. when the meter reads 72 dB it is actually about 75 dB). Does the Galaxy meter need a similar correction factor?

Peace... Vader

"Ya see, we plan ahead. That way we don't do anything right now. Earl explained it to me." - Valentine McKee

One sub to rumble them all. One sub to shake them. One sub to humble them all. And in the darkness break them....
To view links or images in signatures your post count must be 10 or greater. You currently have 0 signatures.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 signatures.
- Not liable for injuries sustained while laughing.
Vader is offline  
post #17 of 45 Old 03-16-07, 02:28 PM Thread Starter
Elite Shackster
 
Sonnie's Avatar
 
Join Date: Apr 2006
Location: L.A. (Lower Alabama)
Posts: 22,577
My System
Re: Galaxy CM-140 Calibration File Info Thread

I'm not sure how anyone could qualify that correction. Your response is not perfectly flat and the SPL meter is going to read the highest peak in your response when that pink noise is playing. If that peak is at 500Hz, then neither meter is really going to need any correction, yet if it were at 20Hz it would... but with pink noise how can you tell where the peak is unless you have an RTA. I think most of the time we see peaks down low in the 30Hz to 60Hz region. With the old RS meters it could mean anywhere from 2db - 7db of correction, with the newer RS meters it could mean from .5db - 2db and with the CM-140, it would not need any at all in that region. So ultimately, I would say you would not need to perform any corrections to the CM-140 for pink noise.
Sonnie is offline  
post #18 of 45 Old 03-16-07, 03:40 PM
Senior Shackster
 
Vader's Avatar
Derek
 
Join Date: Jul 2006
Location: Colorado
Posts: 402
My System
Re: Galaxy CM-140 Calibration File Info Thread

Sonnie,

Ron had me use that correction when we were trouble-shooting my first cylinder last year. He had me run several tests using both my AVR test tones and DVE (which is 10dB hot on the sub test). When I reported the results of the sub tests, I thought they were all 2-3 dB low, but Ron said they were spot-on, because of this correction. Based on this, I calibrated the subs to "flat" with respect to the meter, so it would really be 2-3 dB hot (or so I understood).

Edit: My wife just called and said that my meter came today, so I guess I'm gonna be re-calibrating tonight. It will be interesting to see how far off my old Rat Shack meter really is (I bought it when I was in college - 1991 - and have never re-calibrated it...). Thanks so much, Sonnie!

Peace... Vader

"Ya see, we plan ahead. That way we don't do anything right now. Earl explained it to me." - Valentine McKee

One sub to rumble them all. One sub to shake them. One sub to humble them all. And in the darkness break them....
To view links or images in signatures your post count must be 10 or greater. You currently have 0 signatures.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 signatures.
- Not liable for injuries sustained while laughing.

Last edited by Vader; 03-16-07 at 03:46 PM.
Vader is offline  
post #19 of 45 Old 03-16-07, 08:28 PM
Elite Shackster
 
Ilkka's Avatar
Ilkka
 
Join Date: Jun 2006
Location: Finland
Posts: 1,468
Re: Galaxy CM-140 Calibration File Info Thread

Quote:
Vader wrote: View Post
Sonnie,

I have always read that the Rat Shack meter is 2 to 3 dB low when using the pink noise on DVE to calibrate (ie. when the meter reads 72 dB it is actually about 75 dB). Does the Galaxy meter need a similar correction factor?
DVE's pink noise is not good for setting up the subwoofer level. It's too wide band to be accurate if your frequency response isn't close to dead flat. Especially any amount of "room curve" can cause one very interesting results. AVIA and pretty much all receivers have band limited pink noise for setting up the subwoofer and speaker levels. Usually the noise for subwoofer is limited in ~40-80 Hz range. Since normal C-weighting reads around 1-2 dB low in that range, the same amount of correction is needed for the CM-140 too. So adjust your subwoofer to output around 73-74 dB on the CM-140 when using your receiver as the source. With DVE it's much more difficult to define the correct compensation but around 2 dB is a good starting point. Your ears should always be the final judge, don't just blindly trust on the SPL meter. If the subwoofer sounds too loud, turn it down.
Ilkka is offline  
post #20 of 45 Old 03-16-07, 09:14 PM
Senior Shackster
 
Vader's Avatar
Derek
 
Join Date: Jul 2006
Location: Colorado
Posts: 402
My System
Re: Galaxy CM-140 Calibration File Info Thread

Ilkka,

So you would recommend that I use the AVR's TT instead of DVE? I had always heard that DVE was the better way to go because it tests the entire signal path (from DVD player --> AVR to Speakers --> SPL meter). What you say makes perfect sense too. What about the other channels? Would it be better to simply calibrate all of them to keep consistancy, or use DVE for everything except the LFE channel? I know, I need to get AVIA.... just haven't gotten around to it yet.

Peace... Vader

"Ya see, we plan ahead. That way we don't do anything right now. Earl explained it to me." - Valentine McKee

One sub to rumble them all. One sub to shake them. One sub to humble them all. And in the darkness break them....
To view links or images in signatures your post count must be 10 or greater. You currently have 0 signatures.



To view links or images in signatures your post count must be 10 or greater. You currently have 0 signatures.
- Not liable for injuries sustained while laughing.
Vader is offline  
Reply

Bookmarks

Tags
calibration , cm140 , file , galaxy , info , thread

Quick Reply
Message:
Options

Register Now




PLEASE COMPLETE ALL REQUIRED FIELDS BELOW... THANKS!

REQUIRED FIELDS ON THIS PAGE
YOU MUST COMPLETE ALL OF THESE

Username
Password
Confirm Password
Email Address
Confirm Email Address
Random Question
Random Question #2




User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
PLEASE READ BELOW PRIOR TO ENTERING AN EMAIL ADDRESS!

ATTENTION!

YOU MUST ACTIVATE YOUR ACCOUNT!

Activation requires you reply to an email we will send you after you register... if you do not reply to this email, you will not be able to view certain areas of the forum or certain images... nor will you be able download software.

AN INVALID EMAIL ADDRESS WILL CAUSE YOUR ACCOUNT TO BE DELETED!

See our banned email list here: Banned Email List

We DO NOT respond to spamcop, boxtrapper and spamblocker emails... please add @hometheatershack DOT com to your whitelist prior to registering or you will get nowhere on your registration.


Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML is not allowed!
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


For the best viewing experience please update your browser to Google Chrome