Brief test to see how well the ZITA-NJbridge software would do at streaming high quality, extreme QRQ CW, high speed Morse Code audio tones over the LOCAL AREA NETWORK(LAN)(audio OVER ip). 2 tests were done, one using a "16 bit" digital audio PCM ZITA-stream and another test using a "24 bit" digital audio PCM ZITA-stream. The ZITA-PCM 24 bit audio stream won the contest by a wide margin, and preserved perfectly, the pure audio spectrum of the original Morse Code audio Spectrum as observed on an Audio Spectrum Analysis software APP called Spectralissime.
Here is the SPEC AN READOUT of the Zita-NJbridge in 16 bit PCM audio streaming mode, with the original spectrum on the left and the "streamed" audio after going through the ZITA audio OVER ip TUNNEL - on the RIGHT :
and here are the 24 bit ZITA audio OVER ip streaming results... LEFT is original, RIGHT is the 24 bit ZITA-streamed
As you can see, the 24 bit stream preserves the original SPECTRUM of the QRQ CW tones the best
here are the two commands used on the TRANSMITTER STATION
16 bit - "zita-j2n --chan 1 --16bit 192.168.1.101 5001"
here is the command for 24bit (24 bit is default and you don't have to add any extra commands)
24 bit - "zita-j2n --chan 1 192.168.1.101 5001"
NOTE: FLdigi was set to transmit on its QSK mode - RT channel audio output - a 1khz square wave tone - continuously sending the letter "S" at 200 wpm(to create the most possible edge noise)...this FLdigi "keying" signal, was then used to KEY a different software CPO called the ZamGate CW KEYER. The ZamGate CW KEYER has a very pure audio spectrum output when keyed at QRQcw; as you can see from the original SPEC AN pictures shown above(left side of both pics)
Just to compare how well the ZITA-NJBRIDGE does at preserving the original QRQcw Morse Code Audio Spectrum, here are a couple more examples of tests that were also run...both of the AOIP programs, shown below, still fall short of the excellence of the 24 bit Zita-njbridge PCM AUDIO Stream
Here is yet another similar program called Gstreamer(which is using OPUS CODEC compression at 128k bit rate 48k sample rate)....the original on the LEFT, the Gstreamer(OPUS) SPECTRUM READOUT on the right: