What are the key differences between the free, Plus & Pro versions of Fidelizer?
"The Free version is what I've been developing 3 years ago which is still being maintained. My original purpose was to improve computer audio on everyone's PC. The Plus version works similar but with improved optimizations and no opening hom epage after optimizations, to protect vendors secretly taking advantage of Fidelizer. The Pro version can behave like part of a system startup with more flexible customization. It includes permanent optimizations for full-scale operational improvements.".

If a customer uses Tidal or Roon but outputs to JPlay, what audio player should they check off in Fidelizer Features? Should it be Roon/Tidal or JPlay?
"They should select Tidal, Roon or any other software players they run with JPlay ASIO/Streamer. Only Jplay Mini is a valid selection for music player applications."

What other areas of improvements/features are you contemplating for future versions of Fidelizer?
"I intend to still improve compatibility with Windows 10, Audiophile Optimize and JPlay, then fix all remaining bugs. After that, I'll do some research into my ultimate music server project to see what else I can bring to everyone's PC." [His own system at right.]

Is there anything else a user can do to improve their sound quality with computer-based playback?

"Yes. There are many optimizations which can be done but let's start with the basics, aside from using Fidelizer Pro: upgrading to Windows 10, enabling HPET and improving accessories for cleaner power delivery. By cleaner I mean better parts that pollute less, like upgrading the power supply, power receptacles, power cords etc." (Note: To enable HPET high precision event timer, open up a command prompt with admin rights, type "bcdedit /set useplatformclock true" without quotations, press enter and then reboot. Also ensure that HPET is enabled in BIOS. Google "HPET tweak" for more information.)

What do you say to those who claim "bits are bits" and that programs such as Fidelizer cannot have any effect on sound quality?
"Although some people can't hear the improvements with Fidelizer for various reasons, digital audio doesn't send audio data as 0 and 1. It sends a physical electron pulse with modulation to decode 0 and 1 at precise timing. Things can go wrong little by little to a far greater extent than people are aware of. Please read this for the truth on bit-perfect playback."

Why does reorganizing priorities of various programs/processes as well as reducing the amount of services and background processes in Windows effect sound quality?
"Because there's an interrupt function in the OS architecture where process-switching context is based on a given priority. Reducing non-audio processes priority and isolating them into other cores helps audio tasks to work more efficiently with less interrupt switching."

On your "about the developer" page, you mention that high-end music servers do not offer the same degree of "good dynamics-revealing resolution" as a high-end CD transport. Do you still believe that or has file-based playback surpassed high-end transports sonically?
"Of course. Through my studies and experiments, optical media remain better than magnetic or solid-state drives. Even memory playback won't negate storage jitter problems entirely. Listening to DSD files on a DVD is still better than hearing them from HDD/SSD. I've owned a few high-end models from Esoteric and EMM Labs, not to mention many others which I listened to and played with. Esoteric is truly the world's best transport. The quality of media is no less important than other parts."

When opening Fidelizer Pro for the first time, you will see three optimization levels which progressively increase resource utilization of Windows for music playback: Workstation, Audiophile and Extremist. Workstation is Fidelizer's default optimization which aims to enhance sound quality without adversely affecting system performance. This would be ideal for those who simultaneously use their PC for non-audio related tasks such as web browsing.