Hi all,
Whilst most of the technical test and and measurements are performed by Amir in this forum, a number of members including myself contribute measurements from time to time. I will probably be contributing more to this testing over the next year as I have more free time available (Yay! ) To help make this data more consistent, comparable and easy for the readership to understand, we really should define some standards that we work to. I.E. type of test and purpose, acquisition and processing parameters, graph display parameters etc.
Also, Amir is the only one of us (that I know of) that has consistent access to what I consider "professional" test and measurement equipment. I do on occasions. Having said this some audio ADCs have excellent performance which puts them close to something like an AP and actually quite suitable for this sort of testing. Problem is we dont know how they compare in absolute terms to Amirs AP unit. So I suggest, for those that want to contribute to measurements, we could pass around a test unit (such as a dac) measure it consistently and see how they compare to validate our "domestic" measurement systems.
As DACs are currently the most popular measured device, shall we start with some suggestions for tests? We can move on to specific parameters afterwards.
My 2 pennies. Please add/remove/discuss
Thoughts?
Whilst most of the technical test and and measurements are performed by Amir in this forum, a number of members including myself contribute measurements from time to time. I will probably be contributing more to this testing over the next year as I have more free time available (Yay! ) To help make this data more consistent, comparable and easy for the readership to understand, we really should define some standards that we work to. I.E. type of test and purpose, acquisition and processing parameters, graph display parameters etc.
Also, Amir is the only one of us (that I know of) that has consistent access to what I consider "professional" test and measurement equipment. I do on occasions. Having said this some audio ADCs have excellent performance which puts them close to something like an AP and actually quite suitable for this sort of testing. Problem is we dont know how they compare in absolute terms to Amirs AP unit. So I suggest, for those that want to contribute to measurements, we could pass around a test unit (such as a dac) measure it consistently and see how they compare to validate our "domestic" measurement systems.
As DACs are currently the most popular measured device, shall we start with some suggestions for tests? We can move on to specific parameters afterwards.
My 2 pennies. Please add/remove/discuss
- Frequency response - 44, 48, 88 & 96 kHz replay bandwidth. Extend acquisition bandwidth beyond replay to show filter roll off and out of band noise
- No signal noise floor
- 1kHz tone @ 0dB, -1dB, -60dB FS. THD + Noise
- 48kHz J test. USB and spdif input (if available)
- Intermodulation 19kHz + 20kHz ???
- Small signal time waveform 16 bit and 24 bit @ -90 something dB
Thoughts?