Reviewer: Paul Candy
Financial interests: click here
Digital source: CEC TL51X transport,Asus laptop, Win 8.1, J. River Media Center 20, JPlay 6.2, Roon, Tidal, Audiomat Maestro 3 DAC
Analog source: Well-Tempered Lab Amadeus with DPS power supply, Pro-Ject Tube Box SE phono stage, Ortofon Rondo Blue MC cartridge
Amps: Audiomat Opéra Référence integrated
Speakers: Jean-Marie Reynaud Evolution 3, REL Q108 Mk II subwoofers (2)
Cables: MIT Magnum M1.3, Sablon Audio Panatela, Light Harmonic LightSpeed USB cable, Sablon Audio LAN cable
Power cords: MIT Magnum AC1, Sablon Audio Corona series, Wireworld Aurora & Silver Electra.
Stands: IKEA Besta, IKEA bamboo cutting boards
Powerline conditioning: Audio Sensibility Statement SE Power Distributor [on loan], Blue Circle FX2 6 X0e, Blue Circle BC86 MK5
Sundry accessories: Audioquest Jitterbug, UpTone Audio USB Regen, Acoustic Revive RR-77, Audio Magic/Quantum Physics Noise Disruptors, Caig Pro Gold, Echo Busters acoustic room treatments, Isoclean fuses, HiFi Tuning Disc Demagnetizer, Nitty Gritty record cleaning machine, Soundcare Superspikes (on speakers), dedicated AC lines with CruzeFIRST Audio Maestro outlets
Room size: 11x18x8, long wall setup, suspended hardwood floors with large area sisal rug, walls are standard drywall over Fiberglas insulation
Review component retail: $69.95

For several years and on various online computer audio forums, there have been plenty of tips, guides and shareware scripts regarding optimizing computer operating systems for file-based music playback. Being somewhat computer savvy, I probably spent far too much time playing around with Windows settings, disabling unnecessary resource-heavy services, tweaking BIOS settings and so forth, all of which have improved sound quality to varying degrees. For example, the average Windows PC has typically 65+ running processes and 1500+ threads. I can reduce those numbers to less than a third and the improvement to sound quality is substantial. It appears that the fewer tasks an OS performs, the better the music will sound. A few websites worth checking out for the adventurous are, and There are a plethora of other tips and tweaks that may or may not work for you. However, not everyone has the knowledge and/or inclination to monkey around with their PC. They just want to fire it up, pick an album/track and have at it preferably with the best possible sound quality. Fidelizer Pro is aimed directly at those folks.

Fidelizer Pro was created by Keetakawee Punpeng who operates under the handle Windows X. Fidelizer is a program which optimizes Windows-based computers for file playback and should improve sound quality of any media player such as iTunes, JRiver, Foobar, Roon and JPlay. Fidelizer also supports streaming services such as Tidal, Qobuz, Netflix and YouTube. It is compatible with Windows XP through Windows 10 and Windows Server 2003 to 2016. Even with a terrific sounding player like JPlay, which continues to improve both in sound and features with each new version (JPlay now supports Tidal and Roon), Fidelizer still offers notable improvements. I used the freeware Fidelizer version for several years where it provided a pleasant uptick in sound regardless of what music playback program I have used. Keetakawee  continuously updated and expanded Fidelizer so that it now offers far greater functionality and effectiveness than previous releases. It is also offered in three versions; Fidelizer (free), Fidelizer Plus and the subject of today’s review, Fidelizer Pro. The free version should give a noticeable enough improvement to pique one’s interest in the two other versions. Fidelizer Plus not only offers better sound, it is devoid of the pesky pop-up ad of the freeware. Both of these must be started by the user upon each reboot. Once configured however, Fidelizer Pro will run automatically each time the computer is booted, effectively making changes to Windows permanent. Fidelizer Pro also offers more sound enhancements over the other two versions. During the course of the review, I had a number of questions for Keetakawee: