Ahh…..gotcha. I wouldn’t think Aurender makes CD transport. Bits or digital audio signals are all different, they are not the same. Say if you have two different sources or using two different streamers or music servers going into the same DAC they would sound different although you’re using exact same DAC. Those zeros and ones (binary) are not the same.
In regards to your older Pioneer Elite bluray player used as a CD transport to play Redbook CD, I never had any hands on experience with any Pioneer Elite bluray player or universal disc player. But say just in case if your old Pioneer bluray player dies on you or stop working due to age, you should consider buying a used Oppo 103/105 or 203 universal bluray disc player and use it as a CD transport. Oppo makes great disc transport for very affordable price. I had been using my Oppo 105 as a disc transport going to a separate DAC until I bought a used Cary Audio CD 306 SACD player / DAC (professional edition) 4 yrs ago. The Oppo when used as a disc transport it performs very well, reliable and sounded very good when connected to a high end outboard DAC with a high quality high end digital cable and power cables and good isolation on the Oppo. But my Cary CD 306 SACD player (professional edition) is on another level as its original MSRP was almost 8 times as much as the original MSRP of the Oppo 105 ($1200). The Cary CD 306 SACD player (professional edition) original retail was $8k when it was first introduced back in 2008. Now I run the XLR analog out of my Cary 306 SACD player / DAC to my preamp and use the Oppo 105 strictly for bluray movie and streamed Netflix movie playbacks as well as occasional DVD-Audio high resolution audio music playback and is connected via HDMI to my Classe SSP 800 preamp processor. The Oppo is excellent when used for bluray movie playbacks via HDMI out, even those streamed Netflix movies look very good on the Oppo 105.
Or alternatively for playing CD & SACD and if you’re willing to pay more you should look for a used discontinued Cary Audio CD 306 SACD player / DAC (professional edition) or the non professional edition, the professional edition sounds better but it isn’t like a night and day difference but it is audible and the pro edition is noticeably better. This is an older CD/SACD player / DAC combo, it was first introduced in around 2006/2008 and was discontinued around 2015/2016. These players (both pro and non pro editions) sounded fantastic highly musical very analog like very smooth yet highly resolving but it’s hard to find one in used markets. A used one is probably going for around $2500 to $3500 in used markets if you can find one. This is a statement flagship CD/SACD player from Cary Audio and Cary doesn’t make CD/SACD player anymore. These Cary 306 can be used as a standalone DAC as it has digital audio inputs on the back : AES/EBU, coax digital spdif, optical digital (Toslink). This player is heavy weighing in around 45 pounds and is very well built and designed. it was built like a tank.