Fidelizer review

The question which source is better, CD player or computer/DAC, still seems to inspire many debates among audiophiles. While CD players are very easy to use, with computers, there always seems some potential to be hidden in the form of various adjustments, either in the used audio player or in the host operating system. Windows operating system`s running services are certainly the first “suspicious area” that calls for closer inspection but if the computer is used for many purposes (internet browsing, audio, video reproduction, etc) then some in-depth knowledge is required to perform mods that may or may not bring sonic benefits and besides we still need to make sure everything else will still work as intended. But there's still more to be done that only optimizing the services...

Here comes Fidelizer, a handy program that does the job flawlessly and shows what is possible if computer is optimized to the 9th degree.

"Massively increase audio quality on Microsoft Windows PC using any application, Tidal, Spotify, YouTube and other streaming services.” 

“For the first time ever in Windows to take full advantages of multimedia realtime framework optimizing "Core Audio" to improve Windows audio performance. Fidelizer helps revolutionizing Windows audio quality at foundation level and works well with JPLAY/Audiophile Optimizer.”

Well, all of the above certainly seemed worthy of investigation. 

How Fidelizer works?

You just have to choose optimization level, click “Fidelize”, sit back and listen to the music. You can also choose Customize to pick individual optimizations by yourself to find the optimal point with other optimizations. Fidelizer could do the following functions: 

At the moment there are two version of upgraded Fidelizer, Plus and Pro. Based on Fidelizer Pro which is most advanced version, one gets the following benefits over free version below:

- Can choose whether to apply optimizations one-time or use startup optimizations.
- Core optimizations are reworked for better audio performance and more flexibility to all kinds of audio playback.
- System configuration can be applied with unique tweaks for better audio quality
- Program UI has been reworked to be more friendly with computer audio server projects.
- Optimizations will have improvements over time along with Windows and user feedback suggestion.

I would strongly recommend to anyone interested in computer audio to further explore all possible options on the Fidelizer website as it contains all possible explanations as well as a user guide.

One thing I really liked was to find out this: “While it’s understandable how some customers choose to evaluate test products before purchasing. However, we decided to focus on improving product quality and services without limiting features to test version. We don’t favor the idea of making trial version of Fidelizer Plus/Pro with limited capabilities and it later becomes constraints to further improving software.

Developer put great effort in building good quality software for free. So if you trust in free version’s performance being something worth paying for, you won’t be disappointed in what Fidelizer Upgrade Program can offer you. You can read reviews and how other customers say about Fidelizer after upgrading and make up your mind later.”

This certainly shows the author, Keetakawee Punpeng from Thailand in a very positive light.

In use

To start using Fidelizer, one only needs to double-click the “Fidelizer.exe”, choose the optimization method (WORKSTATION, AUDIOPHILE, EXTREMIST or CUSTOMIZE) and just wait for the program to carry out the chosen optimization, after that everything is ready for the listening sessions.

The sound

Firstly, I have tried the WORKSTATION optimization level. I really didn`t know what to expect but the results floored me! Even at this, basic optimization level the effects on the sound quality were anything but subtle. The gains in clarity, the see-through transparency, resolution and separation of instruments and voices were huge. On top of it: the tonal colors were even truer to life! I was very excited by the results and went on to listen to the familiar tracks. 

The Music

The first track I have tried was the “Sierra Highways” from the Pat Coil - Steps album. This music is actually not “my cup of tea” but I use it frequently for testing purposes because of the quality of the recording. The description says: “Sheffield's 20+ -> 16 Ultra Matrix Processing is a mastering technique that extracts more information from our analog tapes, to be encoded and transferred to the CD master. The process "folds down" 20 bits of digital information onto the 16 bit CD medium using Sheffield's own 20 bit analog-to-digital converter and an Apogee UV22 processor. This technique creates the truest and most accurate CD master from the original analog recording, and is the finest analog-to-digital transfer process currently available.” I couldn`t agree more but if only more music was recorded like that!

Regardless, what was already a great recording, turned into a spectacular one - through the Fidelizer. The piano which already sounded very clear, became even clearer BUT it also gained some warmth and body which was a most welcome trait. The 3D spatial precision was greatly enhanced as well and the depth layering was much improved. The sheer amount of details was also unbelievable. Also the bass gained in control, depth and punch.

Encouraged by the results, I have switched to the EXTREMIST optimization level and was surprised again: the music reproduction quality climbed up a few notches - markedly and indisputably.

I went to check some vocal performances that I know very well, the differences were immediately obvious: again, I have witnessed enhanced clarity, resolution of the tinniest details, better separation and coherence but also less “grit and glare”; a smoother sound overall with less nasty sibilants and nasality. Songs that had traces of grain, now sounded liquid and natural. 

Kelly Sweet` - We Are One (2007) album is full of strong melodies and tasty arrangements. Kelly Sweet was born in Cape Cod, Massachusetts on March 29, 1988, to pianist Jeffrey Howard Sweet and artist Candace Lynn Sweet. Born into a musical household, Kelly was raised on the jazz standards that were part of her father's repertoire. Soon after she could walk, Sweet learned musical notes with her father's help. Her first public performance followed when she was 4 years old at the Cape Cod Conservatory. Her voice has some enchanting qualities and has a great response. Her “Dream On” song is a haunting ballad:

With the Fidelizer EXTREMIST optimization engaged, a very intimate view into her music paintings was possible; one that revealed nuances that I thought were lost in the recording process and mastering. The recording quality among pop albums of course varies greatly; some are downright poor (not only because of compression overkill) and some are surprisingly good. Kelly`s album “We Are One “ is certainly among well recorded ones and the music itself has something to offer as well. 

The “Caresse Sur L'Ocean” (sung in French) is another great example as well as the famous(?) “Je T'Aime”, the latter with piano, guitars and strings weeping in unison with her beautiful voice.

Fidelizer removed the remaining veils and ensured the musical message was delivered in an effortless fashion. 

Moving on to something completely different: Amon Tobin - ISAM. 

Do you have big speakers and want to get scared? ISAM (Invented Sounds Applied to Music) is the seventh full-length studio album by Brazilian electronic musician Amon Tobin. The electronic sounds are mixed with heavily-processed field recordings obtained from a variety of unexpected sources. The end result is difficult to describe and highly unusual (original) but certainly must be experienced to be believed. His live performances are as much a spectacle for the ear as well as the eye:

The fifth track on the album “Lost Found” should serve as a great example of his work; if you listen to it at higher than usual sound pressure levels, you will be every meaning of the word and probably a little scared...

The “Night Swim” and “Morning Ms Candis” are two spectacular tracks showing some, shall I say fearsome percussion sounds and dynamic shifts. The bass was deep, potent and was reproduced with an “iron fist” control. The whole album is full of musical (dynamic) surprises and serves well to test the limits of your system as well as your whole body.

With the Fidelizer, the hair raising effect was only even more pronounced.

The Puppini Sisters` second album “The Rise and Fall of Ruby Woo” is an eclectic mix of musical pieces. It is characterized by the close harmony singing of the three sisters and the album contains covers of popular songs like "Walk Like an Egyptian" and "Crazy in Love" and five original tracks written by The Puppini Sisters themselves. “Could It Be Magic” (written by Barry Manilow · Adrienne Anderson) and "We Have All The Time In The World" (written by Hal David · John Barry, It was a secondary musical theme in 1969 James Bond film On Her Majesty's Secret Service) are certainly the most striking examples of their musical vision:

The Fidelizer excellently portrayed each of their voices and the accompanying instruments. The end result was a very transparent and coherent sonic presentation that carried many “analog” qualities within itself.

Igor Stravinsky`s “Firebird Suite” suite is one of my favorite classical pieces. Wiki says: “It was written for the 1910 Paris season of Sergei Diaghilev's Ballets Russes company, with choreography by Michel Fokine. The ballet is based on Russian folk tales of the magical glowing bird that can be both a blessing and a curse to its owner. When the ballet was first performed on 25 June 1910, it was an instant success with both audience and critics. The Firebird's success also secured Stravinsky's position as Diaghilev's star composer, and there were immediate talks of a sequel, leading to the composition of Petrushka and The Rite of Spring.”

This a marvelous piece of work that also puts the average sound system to a harsh test. With the Fidelizer performing its magic, the sound certainly benefited enormously: the large scale, complex music was handled extremely well, with exceptional separation of the individual instrumental sections, with lots of air around them and with gorgeous brass and string tone. Everything sounded vivacious, dynamic and very exciting. 


The Fidelizer Pro is a marvelous piece of software that unlocks the hidden potential of your PC and enables it to contribute to the overall system`s sound quality at unprecedented levels. The differences in sound quality after the performed optimization procedures were impossible to overhear and were most gratifying; the sonic realism was simply lifted to an entirely different class. Having experienced its magic, I can only conclude that with 39.95 USD (for the Plus version) and 69.95 USD (for the Pro version) it represents an incredible bargain for all those seeking to squeeze the last ounce of performance out of their computer audio setups. 

Highly recommended!

39.95 USD (for the Plus version)
69.95 USD (for the Pro version)

Text: MSK