Richard-
I'm not sure what you are driving towards. I have posted a way to confirm level accuracy at these low levels while making distortion measurements. Verifying ultra low distortion is extremely difficult. If you know your source is clean you can then verify the harmonics using the above techniques. I would use a CLT-1 and see what I get at the higher harmonics since its the only device I know if that is essentially free of HD3 and up. But its really clumsy to use.
I'm not sure what you are driving towards. I have posted a way to confirm level accuracy at these low levels while making distortion measurements. Verifying ultra low distortion is extremely difficult. If you know your source is clean you can then verify the harmonics using the above techniques. I would use a CLT-1 and see what I get at the higher harmonics since its the only device I know if that is essentially free of HD3 and up. But its really clumsy to use.
Its easy question --- how good/accurate is the data at or near and below -100dB being shown by anyone here?
After looking at QA400, all are now suspect to me. [Unless they use a notch filter, I dont trust any of them down there]
Thx-RNMarsh
PS -- hope the CES was fun and good for you. Glad you are back.
A-P 2722 internal source-analyzer loop:
After looking at QA400, all are now suspect to me. [Unless they use a notch filter, I dont trust any of them down there]
Thx-RNMarsh
PS -- hope the CES was fun and good for you. Glad you are back.
A-P 2722 internal source-analyzer loop:
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Just a thought: has anyone here ever used a lock-in amplifier to verify these low level harmonics?
Jan
Can you describe a procedure using a lock in amp?
David.
Very cool. Let us know how it works out.
I am planning to make 3stage cascaded twin-T notch filter...
..... has anyone here ever used a lock-in amplifier to verify these low level harmonics?.....
What is a "lock-in amplifier"Can you describe a procedure using a lock in amp?
...................
Sorry, I didn't realise you guys were internet-challenged
Lock-in amplifier - Wikipedia, the free encyclopedia
Jan
Lock-in amplifier - Wikipedia, the free encyclopedia
Jan
Sorry, I didn't realise you guys were internet-challenged
Lock-in amplifier - Wikipedia, the free encyclopedia
Jan
No just lazy.
I know what a lock in amplifier is just not sure what you have in mind for test.
No just lazy.
I know what a lock in amplifier is just not sure what you have in mind for test.
Ehhh? http://www.diyaudio.com/forums/equipment-tools/248720-emu-1212m-measurements-3.html#post3780049
Jan
The Benchmark would be good but its $1800 and not optimized for measurements. I will do the part swap on the Emu to see what I get. I think an analog upgrade board for the Juli may be the best option for the amateur. I will have demo boards for the ESS ADC soon. I'll see what the best option is.
Sent from my Nexus 7 using Tapatalk
Sent from my Nexus 7 using Tapatalk
Surely, not everyone on the planet is not willing to spend 1800 for a SOTA ADC? It should work very well for T&M with some small additions. It isn't DIY, though.
[I am waiting to receive/listen to the new DAC2 from BenchMark... quad 32 bit !! ]
The ESS should be interesting. I hope you find something that will be small and portable and won't require a notch filter.
Thx-RNMarsh
[I am waiting to receive/listen to the new DAC2 from BenchMark... quad 32 bit !! ]
The ESS should be interesting. I hope you find something that will be small and portable and won't require a notch filter.
Thx-RNMarsh
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