Analog-Precision Board

Products by Analog-Precision => Ultimate-Preamplifier by Analog-Precision => Performance and Measurements => Topic started by: Tranquility Bass on March 25, 2021, 02:24:56 AM

Title: Ultra low level signal resolution 1kHz @ -90dBFS
Post by: Tranquility Bass on March 25, 2021, 02:24:56 AM
Test Methodology:

In this test we are looking at how the DAC is good at resolving very low level signal levels or in other words its micro-dynamic resolving capability. In this case we feed each channel a low level digital signal of -90.31 dBFS which corresponds to a full-scale (0dBFS) signal divided by 32768 or a reduction of signal magnitude by 16 bits which is the lowest level for redbook CD ! This is a 32bit DAC so still has plenty of bits left in the tank to resolve this detail ;)

Conclusion:

Even with a reduction of level equivalent to 16bits in magnitude we see the Ultimate Preamplier has no problem and resolves it cleanly compared to the DEQX Premate which adds a lot of noise and distortion to the signal.

Title: 24-bit Word Length @ 1Khz -90 dBFS
Post by: Tranquility Bass on March 25, 2021, 02:59:14 AM
Below is the real time capture of the Left and Right Channels at -90.31dBFS @ 1kHz 24 bit Wordlength



Below is the FFT Specturm of the output above (Note that any artifacts are buried below -160dB !!)



Title: Performance of DEQX Premate as tested by Stereophile
Post by: Tranquility Bass on March 25, 2021, 03:09:37 AM
Fig.10 DEQX PreMate, waveform of undithered 1kHz sinewave at 90.31dBFS, 24-bit data (left channel blue, right red).
 (https://www.stereophile.com/content/allnic-d-5000-dht-da-processor-measurements-0) 
(https://www.stereophile.com/images/1214DEQXFig10.jpg)

Fig.8 DEQX PreMate, filter operating for Bryston Model T, spectrum with noise and spuriae of dithered 1kHz tone at 90dBFS with: 16-bit data (left channel cyan, right magenta), 24-bit data (left blue, right red) (20dB/vertical div.). (https://www.stereophile.com/content/allnic-d-5000-dht-da-processor-measurements-0)

(https://www.stereophile.com/images/1214DEQXFig08.jpg)
Title: Re: Performance of DEQX Premate as tested by Stereophile
Post by: MichaelH on March 28, 2021, 10:16:12 AM
Fig.10 DEQX PreMate, waveform of undithered 1kHz sinewave at 90.31dBFS, 24-bit data (left channel blue, right red).
 (https://www.stereophile.com/content/allnic-d-5000-dht-da-processor-measurements-0) 
(https://www.stereophile.com/images/1214DEQXFig10.jpg)

Fig.8 DEQX PreMate, filter operating for Bryston Model T, spectrum with noise and spuriae of dithered 1kHz tone at 90dBFS with: 16-bit data (left channel cyan, right magenta), 24-bit data (left blue, right red) (20dB/vertical div.). (https://www.stereophile.com/content/allnic-d-5000-dht-da-processor-measurements-0)

(https://www.stereophile.com/images/1214DEQXFig08.jpg)

Once again proving that the DEQX is a pile of junk.