[95bcwh]

All,
  I'm looking for accurate test tones for 2 channel audio between 20Hz to 20kHz.. does anyone know if such thing exists/available on the web for download?

Thanks
barry

[mfsoa]

I think the RealTraps site has a series from 10 - 300 hz, at 1 hz interval. Maybe stereophile test CD for > 300 hz.
When I first used the 10-300 tones I made the mistake of labelling my graph paper starting at 20hz, and I was disappointed that my VR4JRs didn't start registering on the RatShack meter and my senses  untill 28 hz or so - But it was actually 18 hz, I only realized later!
I did find some interesting dips that spanned only 2 to 3 hz, that 1/3 octave tones would miss, just as Ethan says (once again!)

[95bcwh]

Thanks! I just downloaded the tones from Realtrap.com. I did a quick run at my listening position, it's late at night so I use 65dB as reference. Here's the response at my listening position.

http://www.audiocircle.com/index.php?action=gallery;area=browse;album=770&pos=0

I thought it looks REAL bad!!!!!!

Apparently the 18 panels, 4" thick made of 8lb/ft3 rockwool, are NOT enough!!! I have to go to homedepot to grab some more R-13 rolls.

Can anyone suggest how I should fix the dip at 230Hz?

Thanks again!

[95bcwh]

The previous test was done by placing the radioshack SPL meter at roughly 5 ft away from both speakers (measured from center of woofer). My room is about 10ft wide, 9ft tall, and 15ft long.
My speakers were placed about 5ft 4 inches from their back wall, and about 22 inches from sidewalls (measured from center of woofer to walls), I placed my panel on the sides and rears of speakers hoping to reduce the impact of wall interaction. The distance between two speakers, measured between center of two woofers, is about 6ft 4 inches.

I just did another test, moving the radioshack SPL meter closer to the speakers, now it's about 4ft 6inches from both speakers, and I managed to fix the "dip" around 230Hz! See below:
http://www.audiocircle.com/index.php?action=gallery;area=browse;album=770&pos=0

For newbies like me, such excercise is truely eye-opening... how can I not like this hobby!! 

[JohninCR]

I use the tone generator here:
http://www.softpile.com/Multimedia/Audio/Download_10205_1.html
After 30 days you have to buy the unlock code to continue to use
it.  Use it to make or play whatever tones or sweeps you want.

[MaxCast]

See this sticky in the accoustics circle
http://www.audiocircle.com/index.php?topic=17842.0

Make sure the mic is at ear level.
Find your ideal listening position and move the speakers first, if you can.
Do some research on listening position if you have that adjustability.
18 traps is a lot.  how do you have them placed?

[Joules]

http://www.marchandelec.com/sweeps.html
http://www.marchandelec.com/fg.html

[zybar]

You need to measure at your listening position (at ear level), not near the speakers.

Also, are you using the correction table for the SPL Meter?  If not, you don't have accurate readings and it will mess things up.

Glad to see you putting a lot of time and effort into room acoustics.  Once you get a little more time under your belt, you will be amazed at how much you can improve or deteriorate the performance of your system by adding/.removing acoustic treatments and changing speaker/listening position placement.

George

[95bcwh]

You need to measure at your listening position (at ear level), not near the speakers.

Also, are you using the correction table for the SPL Meter?  If not, you don't have accurate readings and it will mess things up.

Glad to see you putting a lot of time and effort into room acoustics.  Once you get a little more time under your belt, you will be amazed at how much you can improve or deteriorate the performance of your system by adding/.removing acoustic treatments and changing speaker/listening position placement.

George

My room is too small, I found that when I sit roughly 5ft away from the speakers, I got the best of "in-phase" sound - i.e. the vocal sounds very very real. But of course it sacrifice the imaging a little in terms of "out-of-phase" sound. If I move farther away from the speakers I would lose the vocal.

Right now I have my speakers firing down the longer dimension of my room, but once my Tact arrive, I plan to switch them around and firing them down the shorter dimension, using Tact to control the bass. I have to experiment the difference by placing speakers 8-10ft away from each other.

 

[95bcwh]

See this sticky in the accoustics circle
http://www.audiocircle.com/index.php?topic=17842.0

Make sure the mic is at ear level.
Find your ideal listening position and move the speakers first, if you can.
Do some research on listening position if you have that adjustability.
18 traps is a lot.  how do you have them placed?

MaxCast,
  Check out this ugly room..

http://www.audiocircle.com/index.php?action=gallery;area=browse;album=748

   By the way, they looks much better now, I have covered up all the walls with curtains so you won't see the panels.

[Bob Reynolds]

I didn't think you could really fix bass frequencies with room acoustics, at least not 20dB bumps. Looks like you need an equalizer. Have you tried measuring each speaker individually?

[95bcwh]

I didn't think you could really fix bass frequencies with room acoustics, at least not 20dB bumps. Looks like you need an equalizer. Have you tried measuring each speaker individually?

Bob,
   No I haven't tried that.. I'm new to this thing, how does measuring each speaker individually help?

   Thanks
   barry

[Bob Reynolds]

I didn't think you could really fix bass frequencies with room acoustics, at least not 20dB bumps. Looks like you need an equalizer. Have you tried measuring each speaker individually?

Bob,
   No I haven't tried that.. I'm new to this thing, how does measuring each speaker individually help?

   Thanks
   barry

The room measurements I've made in the past were done just like you're doing, except I was using 1/3 octave warble tones (Stereophile test CD). Some time later I installed an M&K subwoofer and a setup CD came with the bass management controller. You performed the setup on each channel individually. The thing that surprised me was the difference between left and right channels. My room is asymmetrical due to furniture so it made sense after I thought about it a while.

I was wondering if there was a substantial difference in your case and knowing that might help guide you in placing the acoustic panels. I'm also very new at this sort of thing, so take my comments with a BIG grain of salt.

If you would I'd really appreciate hearing about your experience with the Tact unit. Which model did you get? I've been debating for the last 6 months about getting one.

-- Bob

[ericleckey]

A neat program called Room EQ wizard which is free you can create your own test tones in following modes: sinewave, Pink noise in full range - subwoofer range -speaker cal or custom, Log sweap, meas sweep, linear sweep, and square wave.   I downloaded the program to my laptop and output of my laptop connected to my HT sys to cal my subwoofers.  It worked fantastic.  You can create any frequency tone. 

[gitarretyp]

A bit lighter tone generator program is NCH's ToneGenerator. I think the free version is limited to 30 days or something, but that should be plenty of time for you to generate a few test tones.