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Gear / Technical Help => Playback Forum => Topic started by: Swampy on April 14, 2006, 07:28:12 PM

Title: Program to analyze playback frequency response?
Post by: Swampy on April 14, 2006, 07:28:12 PM
Hey all. So I have a decent stereo at my desk, nothing fancy. What I was wondering, is there a program out there that I can get (I know there are really really expensive ones made for PAs, but I cant afford them ;D), that I can play white noise through my system and I set up a measurement mic and it tells me what the frequency response of my system is? I'd know its a little muddy in the low-mid range, and Id like to use my 31beq to get it as close to even frequency response as possible... Can I do this, or am I dreaming? Thanks!
Title: Re: Program to analyze playback frequency response?
Post by: bluegrass_brad on April 14, 2006, 07:48:32 PM
Swampy - You can download a trial version of SMAART that works for like 30 days or so.  Cant remember how long the period is.  I own it and love it.  It is very versatile and makes FOH work so much easier.  You can really get a system tuned before soundcheck with it, and during the show it makes it easy to dial in problem frequencies.  You need a measurement mic to really utilize the performance.  You can get a cheapie and get by (Behringer, Nady, audix) as the main factor is that it is flat line freq. response.  Since you are going to be going to school for sound you might be able to write off a purchase of SMAART and a measurment mic on your taxes.  In any case you can download SMAART for a free trial to use for measuring your frequency response.
http://www.siasoft.com/products/demos.html
Title: Re: Program to analyze playback frequency response?
Post by: Swampy on April 14, 2006, 07:53:13 PM
Swampy - You can download a trial version of SMAART that works for like 30 days or so.  Cant remember how long the period is.  I own it and love it.  It is very versatile and makes FOH work so much easier.  You can really get a system tuned before soundcheck with it, and during the show it makes it easy to dial in problem frequencies.  You need a measurement mic to really utilize the performance.  You can get a cheapie and get by (Behringer, Nady, audix) as the main factor is that it is flat line freq. response.  Since you are going to be going to school for sound you might be able to write off a purchase of SMAART and a measurment mic on your taxes.  In any case you can download SMAART for a free trial to use for measuring your frequency response.
http://www.siasoft.com/products/demos.html
Nice! I didn't know they offered a trial version. Maybe I can convince the club I work at to by a copy :hmmm: I already have a pair of the Behringer measurement mics, so Im good to go there. Thanks for the ideas about taxes too! :D
Title: Re: Program to analyze playback frequency response?
Post by: bluegrass_brad on April 14, 2006, 07:58:37 PM
If you plan on doing alot of FOH, especially if you are going to be doing it in different venues, than it is $695 well spent.  Also as far as taxes, if you do some FOH gigs on the side for extra $$$ then why not report that income as an independant contractor (as in you are your own business).  sure you might have to pay taxes on that income, but you can write off your gear purchases.  That's how I was able to swing buying it.
Title: Re: Program to analyze playback frequency response?
Post by: Swampy on April 14, 2006, 08:11:13 PM
very good points! Thanks for the help.
Title: Re: Program to analyze playback frequency response?
Post by: BobW on April 14, 2006, 10:43:29 PM
good call
too bad someone hasn't put out something similar as freeware

Don't forget that Wavelab, SoundForge, and Adobe Audition all have "basic" spectrum analysis tools
Calibration is manual, learning curve is great.  Phase analysis is in Audition as well.
Title: Re: Program to analyze playback frequency response?
Post by: BC on April 15, 2006, 03:29:30 AM
I think some different programs allow you to generate test tones at certain frequencies, you could create different tracks at different frequencies to play back.

Title: Re: Program to analyze playback frequency response?
Post by: live2496 on April 19, 2006, 11:50:34 PM
One excellent tool for audio frequency analysis is actually a mastering tool. However, it has a variety of uses one of which is setting playback equalization.

Har-Bal (Harmonic-Balancer) as it is called will draw a frequency trace of the amount of energy in the audio spectrum. As I mentioned, the primary use of this tool is mastering. In that application you would analyze a mixed down audio track and make note of any problematic resonances. Har-Bal can be used to design a equalization curve that will correct any problematic frequencies. Once any resonances have been reduced, the overall volume can be increased resulting in louder CD's without abusing compression. This is one of the most useful tools that I have encountered. Another secret is that it balances the audio. So, for example if you drop a frequency by a certain amount, it will compensate by increasing all other frequencies equally.

In setting up room equalization, you could use this to visually analyze a frequency trace (ie. recorded) of pink noise played back over your speakers. You would use an instrumentation mic, or a flat sounding omnidirectional mic. I did this in a studio and it helped identify a small problem in the room, and helped confirm that the equalization was pretty much on track.

I just came across this thread "correcting your acoustic room environment". It looks to be very helpful and related to this thread.
http://www.har-bal.com/ipw-web/bulletin/bb/viewtopic.php?t=244
There are lots of good ideas on their forum.

Har-Bal is a good deal at $99. Support from Paavo and Earle is good, and the forum is top-notch. I would recommend it. They also have excellent tutorials to help you get started.
http://www.har-bal.com


Gordon
www.gidluckmastering.com

 



 


Title: Re: Program to analyze playback frequency response?
Post by: BobW on April 23, 2006, 10:28:39 PM
Once again, Thanks, Gordon !

One excellent tool for audio frequency analysis is actually a mastering tool. However, it has a variety of uses one of which is setting playback equalization.

Har-Bal (Harmonic-Balancer) as it is called will draw a frequency trace of the amount of energy in the audio spectrum. As I mentioned, the primary use of this tool is mastering. In that application you would analyze a mixed down audio track and make note of any problematic resonances. Har-Bal can be used to design a equalization curve that will correct any problematic frequencies. Once any resonances have been reduced, the overall volume can be increased resulting in louder CD's without abusing compression. This is one of the most useful tools that I have encountered. Another secret is that it balances the audio. So, for example if you drop a frequency by a certain amount, it will compensate by increasing all other frequencies equally.

In setting up room equalization, you could use this to visually analyze a frequency trace (ie. recorded) of pink noise played back over your speakers. You would use an instrumentation mic, or a flat sounding omnidirectional mic. I did this in a studio and it helped identify a small problem in the room, and helped confirm that the equalization was pretty much on track.

I just came across this thread "correcting your acoustic room environment". It looks to be very helpful and related to this thread.
http://www.har-bal.com/ipw-web/bulletin/bb/viewtopic.php?t=244
There are lots of good ideas on their forum.

Har-Bal is a good deal at $99. Support from Paavo and Earle is good, and the forum is top-notch. I would recommend it. They also have excellent tutorials to help you get started.
http://www.har-bal.com


Gordon
www.gidluckmastering.com