This post describes my subjective impressions of these DACs, level matched with instant switching.
It is not a double-blinded multi-run statistical analysis of anything. I know what those are, and this is not that.
Even if sighted tests are not your thing, the setup is fun. IMO, of course.
Note: Most images a thumbnails, so click to enlarge.
After endless futzing with Windows 11 and Roon, I got tired of noticeable differences in playback, which I blame on Windows/NUC.
I could never get Windows 11 to start Roon automatically and got tired of trying so I decided to ditch Windows for a Roon Rock.
I bought a NUC 12 I5-1240P (for headroom if I decide to DSP) and loaded Roon Rock, stuck it in the closet next to the network gear.
The BIOS is set to boot on loss. Problem solved. This in turn, led me to play with Raspberry Pi (RAAT) endpoints.
Then, I started watching videos, read the thread on ASR on I2S, and thought it might be fun to compare USB to I2S connectivity.
ASR SINAD DAC had the Topping D90 on top and it had every connection (I2S, AES, USB, SPDIF), so I bought one from Amazon.
I2S has to wait for a NUC parts so I set about to compare these two DACs.
The Benchmark DAC3 and Topping D90LE are connected to the ARX RS-1 automatic switch using a Wi-Fi enabled Shelly1 relay.
The Shelly 1 web page power button remotely switches the XLR output from each DAC with slight pop, but no detectable delay.
- Benchmark DAC3 set to HT modes (Fixed volume) and 4 Volt output
- Topping D90LE set to XLR out, filter 5 (linear phase fast) DAC mode (Fixed volume)
- Benchmark AHB2 driving Revel M126be monitors
- Raspberry Pi 3B+ and Pi 4B with DietPi and Roon RAAT (minimal configuration)
- Pangea USB cable and Monosaudio 4N $15 USB cable (quite nice for the money)
- ARX RS-1 configured with a 12-volt trigger to select the XLR input
- Shelly 1 relay with Wi-Fi and a web app to select the input
- Roon DSP volume control, level matching, and grouped zones for simultaneous playback
View attachment 268915 View attachment 268916
The levels were matched using the Roon DSP volume control and measuring the voltage (using a FLUKE 87V true sinewave multimeter) while playing a 1 kHz 0dBFS tone into the M126bes.
The target voltage is 2.83 volts, commonly used since at 8 Ohms this is 1 watt. This was also the listening level used.
D90 2.807 volts: View attachment 268913
DAC3 2.825: View attachment 268918
The DAC3 has a slightly more output of 0.018 volts.
I am no EE, but I supposed that voltage is linear to dB, so I measured the DAC3 adjusting the volume down 1 db.
The 1 dB difference reduced the voltage by 0.244, so (if this calculation makes sense) the volume difference is 0.07 dB by voltage, well below the commonly recommended 0.1 dB level match.
View attachment 268917
The iPad ran Roon to select tracks and the iPhone displayed the Shelly1 web page to switch inputs at the press of the web power button.
View attachment 268922
Is there an Audible Difference
Let me say for the record, that if I sat a family member down and switched DACs they would not know the switch happened.
If I walked into the room, I probably would not know which DAC was playing.
Still, with instantaneous switching, I do detect some differences.
The D90LE adds a bit to female vocals that result in a slightly more pronounced sibilants.
On some tracks with a great deal of ambience, the D90 seems to a more expansive sound, where the DAC3 sounds a hair more damped.
There are times with the emphasis does not strike me as quite right but, it could easily be more accurate.
The DAC3 seems to be a bit better defined dynamics where the instruments have a bit more impact.
Tracks used for vocals and ambience:
- I See Fire - Jasmine Thompson
- California Dreaming - Diana Krall
- Tall Trees in Georgia = Eva Cassidy
Tracks used for detail and impact:
- Undiscovered First - Feist
- Santa Monica Dream - Angus & Julia Stone
- La Bell Dame Sans Regrets - Sting
So, I do think there are very subtle detectable differences.
Amazon D90LE order debacle
I bought this from Amazon from the KGUSS Store but it appears to be used and not new as advertised.
- It has the wrong remote that does not appear as the pictures and does not work with the D90LE (see image below).
- The settings were not factory, it was in DAC mode and to RCA only.
- The packaging looked disheveled.
- There was not protective plastic on the display (I don't know if there should be, but most products at this price range have it).
Here is a picture of the remote (that clearly is not the one for the D90).
View attachment 268914
The D90LE is going back to Amazon.
I performed a blind test, full post here:
Disclaimer: This post describes my subjective impressions of these DACs, level matched with instant switching. It is not a double-blinded multi-run statistical analysis of anything. I know what those are, and this is not that. :) Even if sighted tests are not your thing, the setup is fun. IMO...
The results: I correctly identified the DAC3 from the D90LE 2/3rds of the 15 attempts.
Edit 7Mar2023: Here is the simplified version of the results, the old version was causing confusion. A thumbnail of the original presentation is provided below.
View attachment 270037
View attachment 270039
I think this is meaningful, others may not.