Looking for a frequency response program for my laptop... (1 Viewer)

[Jim A. Banville]

I have a Compaq 1200US Presario laptop. I beleive sound and video are "on the board", so it doesn't ave any fancy sound or video cards. It does have mic and headhone jacks. Does a program exist that has test tones that could be output via the headphone jack of the laptop, to a L/R analog input on my receiver, which outputs the test tones through my main speakers, and which is picked up by a microphone attached to the mic input on the laptop and it turned into a nice frequency response graph on my laptop's display?

thanks

Jim

 

[ColinM]

http://www.spectraplus.com/
You could try this...
My thinkpad won't do play/record at the same time, so I burned a copy of the sweeps etc and played it back while measuring.
I'm still getting used to it.

 

[ThomasW]

You'll need a duplex soundcard to record and play back at the same time. Most laptops don't have these.
The SpectraPlus is a nice program but if you want to use it after the 30 days it costs about $1K. Also if you install it, it can't be completely deleated from the computer since it writes to a specific section of the HD as a part of it's copy protection. So removing it completely requires reformating the HD.
ETF 5.0 and TrueRTA are nice programs that won't break the bank

 

[Brian Bunge]

Do any of you computer nerds...er, uh, I mean experts know if there are any laptops that come with full duplex soundcards or is it a special order type item that you'd need to purchase?

Brian

 

[Andrew Low]

My thinkpad 600x seems to have a full duplex card.

Roo

 

[ColinM]

The SpectraPlus is a nice program but if you want to use it after the 30 days it costs about $1K. Also if you install it, it can't be completely deleated from the computer since it writes to a specific section of the HD as a part of it's copy protection. So removing it completely requires reformating the HD.

Yipes!

 

[ColinM]

How can I lower the noise floor?

In RTA I get a big bump from 200 on down.

??

 

[Ranga]

My Dell Latitude CPA has a full duplex card. I used the demo version of ETF for my readings.

 

[Mark Krawiec]

you can also get an external usb sound card, like the soundblaster extigy, assuming your laptop has usb and you can get the driver/bios/software to all behave.

 

[ThomasW]

Mark's right the about the USB based Extigy from SB. Also available is the Waveterminal U24
There's a forum dedicated to laptop audio
http://groups.yahoo.com/group/laptop-tapers/

 

[Jim A. Banville]

Okay, TrueRTA requires "full duplex 16 bit sound capability". What does that mean? How do I check if I have this?

thanks

Jim

 

[rich r]

Hey all,

Does anyone have a site listing the compatibility of such sound cards!!!

-=-i plan on using true RTA but again I am another one that does not know if I have a 1/2 or full duplex card.

I am using a SB live Value sound card and creative's web site is unable to tell me if its full duplex or not!!

also has anyone have a full version of "True RTA" and if so is it worth buying or would you guys recomend something else.

thanks for any input in advance

 

[ThomasW]

Full duplex capability can be checked by downloading a copy of ETF 5.0 and running the set up part of the program. It involves creating a loopback between the input and output of the soundcard. Then seeing if the card will both send and receive signals at the same time.
Either ETF 5.0 or TrueRTA can be used with a nonduplex card. Doing that requires a source for sending the test signal (pink noise, white noise, sine waves, etc) to the speaker via a different source than the laptop. They can be simply be burned to a CD. The ETF 5.0 website has downloadable files that are used for testing full duplex capability and sending a test signals through your main speakers for running the program with a nonduplex soundcard. The duplex loopback test file contains a 19Khz tone. Some people won't be able to hear it. But yes it's there, and will work for testing duplex capability. Test Signal CD Files
rich
A SB Live value is a full duplex sound card.
I have the TrueRTA 1/24 octave program. I find it better and more accurate than my $1K AudioControl SA-3501 RTA

 

[Brian Bunge]

Thomas,

If the soundcard is not full duplex with the pink noise signals from the Stryke Bass Zone CD be sufficient?

Brian

 

[ThomasW]

Brian

For TrueRTA you need a pink noise signal.

For ETF 5.0 you need the modified white noise signal (it's in their downloadable file).

 

[Brian Bunge]

Thomas,

OK, so if I used ETF I'd need to download and burn their modified white noise signal, yes?

Brian

 

[ThomasW]

The ETF download has 2 parts.

1)A 19Khz for testing duplex soundcards

2)A modified white noise signal for actual speaker testing if the soundcard isn't duplex. If the soundcard is duplex the ETF program itself creates the appropriate test signals from the PC so the burned CD isn't needed

 

[rich r]

Thomas,

Now the mic. question???

what are some cost effective DIY solutions for mic's???

what MIC are you using with your RTA's now, also what commercial mic would you recommend??

 

[ThomasW]

rick

There are a couple of mic options. None are super cheap with the exception of just using the output from a RS meter.

We have a couple of Behringer ECM8000s on order. These are available everywhere for less than $40, but they need phantom power and a mic pre-amp. The cheapest device for that is the Behringer DSP110 ($70), people are finding these a little difficult to operate. A better and slightly more expensive option is using the Behringer VX2000. It's a mic pre-amp with phantom power and is available for $129.

When the ECM2000s arrive, we're going to compare them against a our reference calibrated B&K4133 and see how they stack up. We'll post the results of the comparison