They never said it was going to be easy...
I have Speaker Workshop up and running (side note: the first time you run it under Win 7 you need to do so in Administrator mode, otherwise it can't create some ini files).
Problem 1: the line out from the jig to the sound card input seems way too high. If I even start to push the signal to the jig, the Line In saturates horribly. If I keep levels really low it's fine, I can get a nice sine wave record... but the setup instructions say you need about 2.8V RMS into the resistors. I can push maybe .4V into the system before it starts clipping like crazy, even with sound card input level set to its lowest lowest point. :-\
To get my input signal to the jig, I'm taking the line out from the sound card into a small desktop powered speaker setup, which conveniently has the left speaker connected via an RCA plug, so I can just take an RCA lead from the little amp to the jig.
(Aside: The sound card in my laptop is also pretty crap - it takes 8-12ms before it even starts picking up the output... talk about latency!)
What I don't get is that at a 2.8V RMS signal, that's getting on for 4V peak across the 8ohm reference resistor -- then through the 4k7 resistor, but the input impedance of the sound card should be 10's or 100's kohm, so the sound card would be seeing 3-4V... and a line level should be no more than 1.5-2V (AFAIK).
So that's the big problem ... the second prob is that if I try put it in component measurement mode (i.e. un-bridge BP3/BP4 and change the switches) I just get a horrible sound coming from the speakers (NO idea why... something going mad inside the PC sound card?)
Any thoughts most welcome, I scratched around all over the Interwebs, the forum on the Audua website no longer exists, etc. Stumped.
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I have Speaker Workshop up and running (side note: the first time you run it under Win 7 you need to do so in Administrator mode, otherwise it can't create some ini files).
Problem 1: the line out from the jig to the sound card input seems way too high. If I even start to push the signal to the jig, the Line In saturates horribly. If I keep levels really low it's fine, I can get a nice sine wave record... but the setup instructions say you need about 2.8V RMS into the resistors. I can push maybe .4V into the system before it starts clipping like crazy, even with sound card input level set to its lowest lowest point. :-\
To get my input signal to the jig, I'm taking the line out from the sound card into a small desktop powered speaker setup, which conveniently has the left speaker connected via an RCA plug, so I can just take an RCA lead from the little amp to the jig.
(Aside: The sound card in my laptop is also pretty crap - it takes 8-12ms before it even starts picking up the output... talk about latency!)
What I don't get is that at a 2.8V RMS signal, that's getting on for 4V peak across the 8ohm reference resistor -- then through the 4k7 resistor, but the input impedance of the sound card should be 10's or 100's kohm, so the sound card would be seeing 3-4V... and a line level should be no more than 1.5-2V (AFAIK).
So that's the big problem ... the second prob is that if I try put it in component measurement mode (i.e. un-bridge BP3/BP4 and change the switches) I just get a horrible sound coming from the speakers (NO idea why... something going mad inside the PC sound card?)
Any thoughts most welcome, I scratched around all over the Interwebs, the forum on the Audua website no longer exists, etc. Stumped.
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