You forgot Sam. (And their results are quite different than mine. I look quite lower than they did.)
NOS means non-oversampling and means that there is no digital low-pass filter used. In addition, it means that very often no analog brickwall low-pass filter is used.
The 15 kHz - 20 kHz is part of the original record content while the 24.1 kHz - 29 kHz isn´t; instead it is part of the first mirror image that should be removed by a brickwall low-pass but isn´t.
Just an example what can happen....
Wow!
Assuming a fully loaded car goes for $50,000 and your car vending machine takes quarters, that's 200,000 quarters @ 5.67 grams a piece. You'll need to bring 1,134 kg, or over a ton of change to get your ride!
Crazy crazy 🙂
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Thank-you, Jacob. Ah, this american disease to transform one word on two into an acronym !!!
Do not make-it easy for foreigners, believe-me.
But it was not at all the context of our discussion:
As you see, no question of NOS here. And my answer was taking into account the PSSR (an other acronym ;-) of amplifiers circuits
Anyway, who could use a DA converter without rejecting the sampling frequency, aliasing at work ?
A big misunderstanding, as i supposed.
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I looked at the test maybe I'm wrong as usual but the usual DNR problem with distortion is absent. The input stimulus sees the attenuation of 600 Ohms against the contact resistance while the distortion is 100% caused by the relay. This should be easy to measure to -180dB (1nV) with a pre-amp, long FFT's and lots of averaging.
How does a signal of higher frequency than the driver can reproduce cause a physical offset? Where is the rectification coming from?
jn
If our cars are made of "Tin an tires", speakers are mainly made made, like puppets, of twine and paper ;-)
I just looked across the relay contacts and used a ribbon microphone step up transformer. Distortion range varied from my 8K sample noise limit to 48 dB above that.
Now with relay prices about the same which one would you use?
Signal level from the source was 10 mV RMS at 3,000 hertz. Load was 10,000 ohms.
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The next question would be to compare top of the line relay switching versus straight mechanical switches.
Now quad bifurcated gold/palladium crossbar contacts are the best. There are a few switches built like that. But noted by their absence in modern audio gear. About all that you might see are Shalco silver switches.
A remote control motor can be fitted to the Shalco switches but very hard to beat relays for remote control of inputs and volume.
So far have only tested a few actual rotary switches. My old cheap favorite turned out to be horrible. Sort of the reason I started looking at a method to measure contact issues. Of course all connectors, switches etc. are poifekt...
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Of course I like Shallco switches best, but it will be interesting what you find Ed, with the bifurcated relays. The problem with Shallco switches is that they can tarnish and have to be wiped occasionally just to be sure. Then, of course, there is the remote control problem. Relays are much easier, obviously.
Have you ever looked at the Teledyne relays like the S172, I managed to get a stash of them when they were excess stock (usually $35 or so). Small size and used for extremely critical applications.
Burn them in at moderate volume for at least a month before listening.
I used mono FM with the (out of phase) speakers face to face.
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