Can you hear a difference between dac+amp path with 92dB vs. 78dB SINAD?
Quite a lot has been said here about “audibility” of SINAD, or existing/non-existing sound differences between amplifiers or DACs. Quite often we forget to evaluate SINAD of the whole audio chain consisting of a DAC, power amplifier, and eventually a preamplifier. It is the gain structure of the whole chain and individual noises of the components used that usually define the resulting SINAD of the complete audio chain, in case we have no ground loop issues. The gain structure and noise is a key, as will be explained.
Let's investigate 2 complete audio chains, one of them consisting of a DAC1, analog preamplifier and a power amplifier, the other one just from a DAC2 with digital volume control and the same power amplifier.
Chain1: Topping D10s DAC, OPFET preamplifier with balanced output (my design), Hypex NC252MP power amplifier.
Chain2: iConnectAudio4 DAC with digital volume control, Hypex NC252MP power amplifier.
Output signal is recorded from NC252MP outputs. Output voltage from NC252MP was 0 – 4V, to match common listening level at home listening conditions. NC252MP has 26dB gain (20x), so the DAC or preamp output would be only 0 – 200mV, about 20dB below the DAC full scale output.
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Chain1 with Topping D10s and the preamp shows THD = 0.002%, THD+N = 0.0025% and SINAD = 92.04dB at 4Vrms measured at the NC252MP output.
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Chain2 with iConnectAudio4 shows THD = 0.00098%, THD+N = 0.013% and SINAD = 77.72dB at 4Vrms measured at NC252MP output. SINAD is now of 14dB worse, as a result of higher permanent voltage noise at the output of the iConnectAudio4 DAC analog output. Though there is one componet in the chain missing (the preamp), SINAD is worse due to higher noise of the DAC analog output.
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THD vs. frequency comparison
The same track was recorded through Chain1 and Chain2 and you can download these 2 files from
The files are in 96/24 flac format. You can try if you hear a difference and if you do, please let us know and also post a foobar2000 ABX protocol here.
The files were also compared by Paul's @pkane excellent Deltawe software and these are the results:
------------
And this is my ABX report
______________________________________
Edit
Original file
I am posting the original file as well:
Please feel free to use it in your ABX comparisons as well.
Quite a lot has been said here about “audibility” of SINAD, or existing/non-existing sound differences between amplifiers or DACs. Quite often we forget to evaluate SINAD of the whole audio chain consisting of a DAC, power amplifier, and eventually a preamplifier. It is the gain structure of the whole chain and individual noises of the components used that usually define the resulting SINAD of the complete audio chain, in case we have no ground loop issues. The gain structure and noise is a key, as will be explained.
Let's investigate 2 complete audio chains, one of them consisting of a DAC1, analog preamplifier and a power amplifier, the other one just from a DAC2 with digital volume control and the same power amplifier.
Chain1: Topping D10s DAC, OPFET preamplifier with balanced output (my design), Hypex NC252MP power amplifier.
Chain2: iConnectAudio4 DAC with digital volume control, Hypex NC252MP power amplifier.
Output signal is recorded from NC252MP outputs. Output voltage from NC252MP was 0 – 4V, to match common listening level at home listening conditions. NC252MP has 26dB gain (20x), so the DAC or preamp output would be only 0 – 200mV, about 20dB below the DAC full scale output.
-------------------
Chain1 with Topping D10s and the preamp shows THD = 0.002%, THD+N = 0.0025% and SINAD = 92.04dB at 4Vrms measured at the NC252MP output.
-------------------------
Chain2 with iConnectAudio4 shows THD = 0.00098%, THD+N = 0.013% and SINAD = 77.72dB at 4Vrms measured at NC252MP output. SINAD is now of 14dB worse, as a result of higher permanent voltage noise at the output of the iConnectAudio4 DAC analog output. Though there is one componet in the chain missing (the preamp), SINAD is worse due to higher noise of the DAC analog output.
--------------------------
THD vs. frequency comparison
The same track was recorded through Chain1 and Chain2 and you can download these 2 files from
The files are in 96/24 flac format. You can try if you hear a difference and if you do, please let us know and also post a foobar2000 ABX protocol here.
The files were also compared by Paul's @pkane excellent Deltawe software and these are the results:
------------
And this is my ABX report
Code:
foo_abx 2.1 report
foobar2000 v2.0
2023-11-23 15:29:47
File A: dacamp_test1.flac
SHA1: d18e80d55835f5f2db9e29c2246e9bb67e5e36e9
File B: dacamp_test2.flac
SHA1: fbab6bd34063f58dfb5962479bbe62c88810d35e
Output:
ASIO : Topping USB Audio Device
Crossfading: NO
15:29:47 : Test started.
15:31:05 : 00/01
15:31:25 : 00/02
15:31:38 : 00/03
15:31:54 : 01/04
15:32:24 : 01/05
15:32:40 : 02/06
15:33:07 : 02/07
15:33:18 : 03/08
15:33:47 : 03/09
15:34:05 : 04/10
15:34:25 : 04/11
15:34:46 : 05/12
15:35:05 : 05/13
15:35:33 : 05/14
15:35:55 : 06/15
15:36:16 : 07/16
15:36:16 : Test finished.
----------
Total: 7/16
p-value: 0.7728 (77.28%)
-- signature --
4f3a6e8052276d96850c23e7c0f8ee297ffa2ab0
______________________________________
Edit
Original file
I am posting the original file as well:
Please feel free to use it in your ABX comparisons as well.
Last edited: