Yes Toni we have to thank those who contributed with so good models.
Regarding measurement I don't know, it's not my measurement (I wish it is with so good tools what I don't have).
RNMarsh's measurements? Maybe he can bring some light into "darkness"?
I'm owner of a panasonic/levear vp7723d which has different measurement options.
Hi. The 7723 wont go low enough. I used to have one. The test shown is THD only. 2H and 3H only --- nothing seen of higher harmonics. Average... not rms. 8 ohm load.
The EC works amazingly well at all levels and loads and freq. Works extremely well with CFA characteristics.
THx-RNMarsh
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My vp7723d can measure below 0.0005% THD+N @ 20khz. Just using the sweet spot of the oscillator output and the balanced input range. Always included is noise which is of course also important to get a feeling of the overall performance. It is nice to be able to measure a specific harmonic with the vp7722.
With the vp7723d residual output displayed on a spectrum analyzer you can see in detail all harmonics and noise distribution.
Merry christmas to all diy'ers!
BR, Toni
With the vp7723d residual output displayed on a spectrum analyzer you can see in detail all harmonics and noise distribution.
Merry christmas to all diy'ers!
BR, Toni
Most of the time and especially at normal listening output levels, the THD will be well below .001% and often below .0005%. So, you are marginal....... I use 3 instruments ... as the need gets lower and lower in THD/Harmonics.... VP7722, Audio Precision 2277 and the ShibaSoku 725D.
With the 725D and an FFT on its monitor output, -160dBv can be read accurately.
THx-RNMarsh
With the 725D and an FFT on its monitor output, -160dBv can be read accurately.
THx-RNMarsh
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Really impressive measurement tools! Are you meaning AP 2722?
Wow: -160dbV are 0.028 µV Really?
Could you measure the 1W, 50, 100 and 200W@8R performance again using the THD+N function of your VP7722 with 80 kHz bandwidth filter activated. No 400Hz filter active. Using 2x60 - 2x62V stabilized power supply?
Just as reference because our measurement results are different. My results can be found by the link in post #1 of this thread.
Thx in advance, Toni
Wow: -160dbV are 0.028 µV Really?
Could you measure the 1W, 50, 100 and 200W@8R performance again using the THD+N function of your VP7722 with 80 kHz bandwidth filter activated. No 400Hz filter active. Using 2x60 - 2x62V stabilized power supply?
Just as reference because our measurement results are different. My results can be found by the link in post #1 of this thread.
Thx in advance, Toni
This leads to a question. How can-we explain the differences we can feel in our listening experiences, between two different amps with close performances like those ?
It really were a pitty, if we could fully explain that. Then the magic of our hobby were lost ...
Matthias
Do-you really think the magic of motors had been killed by the progress of the telemetry in formula one races ?
Science helps, but never kill the "magic". We can continue endlessly to try to improve our knowledge ;-)
D'accord. I only wrote *fully* explain, and this would be a problem, wouldn't it?
Matthias