[Capmerkev]

Hi, I was wondering how much of a difference it makes to only use the line in with a RS meter without soundcard calibration, for measuring with the RTA and the pink noise file burned onto a cd with the output muted for a rough measurement of low frequency room response.

The reason I am asking is that I only have a laptop and a RS meter. I live in a small Canadian town and I cannot find a external sound card.

I have a two channel audio room and for the moment I am only trying to find the best bass response for seating/speaker position so I am only looking at a narrow frequency range.

 

[Capmerkev]

Sorry perhaps I should have explained this a little better. I not sure if I know less about room acoustics or computers.

For the moment I am trying to find the best low frequency response seating/speaker position for a two channel audio room. I do not intend to use an EQ, but in the future I will be adding room treatments.

Yes, I did mean mic in and do realize that I will not get a truly accruate measurement from a laptop without an external soundcard.

I have a small room which certainly does not have a very flat frequency response(previously I had been trying to use a test cd with low frequency sine waves and the RS meter but found it could take a very long times when trying to test multiple postions).

I was off work this week and had intentions of finding the room responses. But when I tried to find an external sound card I found that I will have to try to order one from somewhere(nobody could help me locally). Realizing this will take anywhere from a week to month to get one. By that time my week is over and I am back to work.

I been playing with REW and speaker/seating positions on my time off. What I had done was copy the Pink Noise PN file and burnt it on to cd. I muted the output volume of the laptop and used the cd to check levels to set the input level to -18 and calibrated the slp meter to 75db with the cd. Then I used the pink noise pn cd with the RTA and was only looking at the 20-300 range. I was not using a soundcard calibration file which measured similar to the output of the builtin laptop speakers(no bass,lots of midrange, and limited highs, cannot expect anything less from these type of speakers).

My thoughts had been that muting the output of the computer, not using a soundcard calibration file and playing the cd from my stereo the effects of the soundcard would be lessened. Although I still used the mic input, I had set it to -18 on the meter level and set the spl to 75db which never drove into clipping with the pink noise.

Anyway I do understand that I cannot get a truly accurate reading without a proper soundcard. I guess I was only hoping if this show where might be close to best place for positioning by looking at the peaks and dips and trying to find the smoothest response. Do you feel that this could put me in the close ballpark until I can get an external soundcard, and then I would only have to do some minor positioning tweaks for a flatter response.
thanks for your time

 

[Capmerkev]

I do appreciate your responses and hope I did not sound like I was trying to disagree or disregard any advice. I was only trying state what I had meant a little more clearly.

I had been looking forward to trying to tune my system a little better during my time off. But was a little heartbroken when I found I could not buy a soundcard in time. I was just trying to make the most of my situation.

As I said earlier, I do not know much about computers(aside from turning them on/off and going onto the internet). As Dave stated, the soundcards that a lot of people use here are not made anymore. And I am unsure which ones will work correctly with REW.

I have been looking on the internet for a soundcard, but I have been trying to look within my own country if possible (absolutely nothing personal, only trying to keep my shipping costs down and avoid the black hole they call Customs). From the sites I looked at there is much available, but I did see the Creative Labs Sound Blaster X-FI Surround 5.1 24 Bit USB External which Dave had mentioned

Will this be an acceptable soundcard for using with REW?

 

[Capmerkev]

Hi maybe another question is would be will this be compatible with my computer?
This is probablya simple answer for someone that has a little understanding about computers.
I have a laptop with Windows XP and a Intel Centrino Duo processor.
I looked in the system requirements section for this soundcard( sorry I am unable to provide a link) on Creative Labs website.
Windows XP seems to be fine but I am unsure of the processor.
It says I need an Intel Pentium 4 1.6 GHz, ADM Athlon XP 2000+ or equivalent processor.
Looking in my system properties I believe I have 2 Intel Core 2 proccessors.
Is Intel Centrino Duo the same or equivalent as Intel Pentium 4?
Please let me know if I should have asked this in a different section