Ranga
Stunt Coordinator
- Joined
- Nov 30, 2000
- Messages
- 107
I am using a Dell Latitude CPi-A laptop with ETF 5.0 demo software and I am not sure if I have the correct connections setup to measure the frequency response.
I used two Radio Shack Adapters (274-369), one connected to the LINE-OUT (the headphone jack) and the other to the LINE-OUT/Audio-in jack. Now the connections -
LINE-OUT jack (Laptop)->BFD 1124's input 1
BFD 1124 output 1 -> sub-amp line-in
LINE-OUT/Audio-in (Laptop)-> Ratshack Meter
LINE-OUT (Laptop) -> LINE-OUT/Audio-in (Laptop) [For sound card calibration).
With this setup, the level check shows different values for the Microphone input (-30db) and Soundcard input (-6db). I could not get them set to the same level.
I then tried the MIC-IN jack on the laptop connected to the Ratshack Meter. With this, both channels were set to -1db. With this setup, when I ran a test measurement, the graph showed a straight line at 100db (almost off the scale).
Checked ETF documentation which recommends that I remove the LINE-OUT->LINE-OUT/Audio-in connection on the laptop. A level check indicated -39db on the Microphone input channel and -34db on the Soundcard input channel. The 2 test measurements give me these graphs -
Link Removed
This doesn't look anything like what I measured manually -
Link Removed
I did read BruceD's post that the connection to the laptop should be to the line-in and NOT the Mic-in. But I could not get the levels set to the same db on both channels.
Would the line-in be equivalent to the Audio-in on my laptop (the jack is described as a record/playback jack?
Any other suggestions?
Ranga
I used two Radio Shack Adapters (274-369), one connected to the LINE-OUT (the headphone jack) and the other to the LINE-OUT/Audio-in jack. Now the connections -
LINE-OUT jack (Laptop)->BFD 1124's input 1
BFD 1124 output 1 -> sub-amp line-in
LINE-OUT/Audio-in (Laptop)-> Ratshack Meter
LINE-OUT (Laptop) -> LINE-OUT/Audio-in (Laptop) [For sound card calibration).
With this setup, the level check shows different values for the Microphone input (-30db) and Soundcard input (-6db). I could not get them set to the same level.
I then tried the MIC-IN jack on the laptop connected to the Ratshack Meter. With this, both channels were set to -1db. With this setup, when I ran a test measurement, the graph showed a straight line at 100db (almost off the scale).
Checked ETF documentation which recommends that I remove the LINE-OUT->LINE-OUT/Audio-in connection on the laptop. A level check indicated -39db on the Microphone input channel and -34db on the Soundcard input channel. The 2 test measurements give me these graphs -
Link Removed
This doesn't look anything like what I measured manually -
Link Removed
I did read BruceD's post that the connection to the laptop should be to the line-in and NOT the Mic-in. But I could not get the levels set to the same db on both channels.
Would the line-in be equivalent to the Audio-in on my laptop (the jack is described as a record/playback jack?
Any other suggestions?
Ranga