Audiolab Q DAC measurements

[audio_tony]

This is a relatively old DAC which I think was initially produced around 2013 - so this must be 11 years old now.

It's based around the ESS9016 DAC chip.

My test setup: Asus Xonar STX sound card with a self built buffer / gain box in front of that. Host PC is an Intel i7 running Windows 10 with 32G RAM and SSD - no mechanical disks or CDROM drive present.
I also use an Altor Audio Olivine-2 ADC, however the Asus Xonar was used these measurements.
Sound card input was set to 24bit/96kHz, DAC was set to 24/192kHz
Even though this has a USB input, I used an S.M.S.L. PO100AK as a USB to coax bridge, as the USB input on the Audiolab appears to have some issues.
I used Arta for the measurements.

Spec:

Resolution	32bit
Maximum Sampling Frequency	84.672MHz
Digital Inputs	1 x 24-bit/192kHz Coaxial 1 x 24-bit/96kHz Toslink Optical 1 x 24-bit/96kHz USB
Frequency Response	20Hz-20kHz (+/-0.2dB)
Total Harmonic Distortion (THD)	0.002%
Dynamic Range	>110dB
Crosstalk	112dB
Analogue Output Connections	1 pair RCA Phono
Digital Output Connections	1 x RCA Phono and 1 x Optical TOSlink

THD 0dB

THD -3dB

THD -6dB

THD -30dB

THD -60dB

THD -90dB

Frequency response using Arta's sweep.

Frequency response (smoothed white noise):

Jitter:

Multitone (I just can't seem to get this right...)

Digital silence:

 

[AnalogSteph]

Jitter:

This might suggest them using a CS84xx receiver with the ESS DPLL being turned off (in the interest of avoiding nasty aliasing when hitting >0 dBFS as typical for ASRCs).

Multitone (I just can't seem to get this right...)

Try using a Kaiser20 window if available, and/or a larger FFTsize.