radix
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I'm new to the QA402, so I wanted to check out a few things with the experts. I have an MC phono preamp that's setup for 62dB gain or switchable to 68 dB.
To measure its performance, I believe I want to do this:
Get a baseline for self-noise and THD+N
- Shunt the L- and R- with 50R caps
- Hookup my BNC-RCA cables input-to-output (I'd use a barrel connector)
- Measure the self-noise (no signal) and THD+N (1kHz) to get a baseline (these are -114 dBV and -81 dBV respectively)
To measure FR
- Select the User weighting and RIAA Record Response
- Use EchoChirp @ -68 dBV (for 0.4 mV) output
To measure gain:
- Select the User weighting and RIAA Record Response
- Use multitone
- view Gain dB
- Should be around 62 dB
To measure THD+N
- Use GEN1 @ 1 kHz and -68 dBV output
- View THD+N
I imagine I'm missing something. Also, are there any measurement threads I missed that go over this already?
Thanks,
Marc
To measure its performance, I believe I want to do this:
Get a baseline for self-noise and THD+N
- Shunt the L- and R- with 50R caps
- Hookup my BNC-RCA cables input-to-output (I'd use a barrel connector)
- Measure the self-noise (no signal) and THD+N (1kHz) to get a baseline (these are -114 dBV and -81 dBV respectively)
To measure FR
- Select the User weighting and RIAA Record Response
- Use EchoChirp @ -68 dBV (for 0.4 mV) output
To measure gain:
- Select the User weighting and RIAA Record Response
- Use multitone
- view Gain dB
- Should be around 62 dB
To measure THD+N
- Use GEN1 @ 1 kHz and -68 dBV output
- View THD+N
I imagine I'm missing something. Also, are there any measurement threads I missed that go over this already?
Thanks,
Marc