After releasing firmware 5.0 in 2022, we’ve been improving Nimitra internally and apply newer changes and improvements over the years until it reaches maturity stage to make it official. Today is the day we can announce official firmware 6.0 update.

Version 6.0 will cover major improvements based on Erawan flagship streamer that can be applied into Nimitra product. Firmware 5.0 was biggest improvement but 6.0 is now bigger with overhaul optimizations and improvements as below.

 

Windows Server 2025 Sound Quality Optimizations

 

After being impressed with sound quality from Windows Server 2022 for the first time enough to put onto Nimitra firmware 5.0, Windows Server 2025 made further improvements and changes are tailored for Nimitra to bring streaming closer to real sound.

Erawan was launched in the same month as Windows Server 2025 being released officially so we have been working closely with 24H2 codebase since the first beta. We’ve been optimizing Erawan until last week before making local launch in November 2025.

It’s quite fortunate for Nimitra that changes from Windows Server 2025 can blend smoothly with NimitraOS optimizations making Nimitra Classic and Nimitra2 sounding a lot closer to Erawan at much more affordable price point.

 

Universal Core Isolation Policy and Playback Optimizations

 

 

When firmware 5.0 was released, it was mainly for Roon optimizations at first and we put JRiver improvements during last minute before official launch. After Roon failing to meet our expectations, we started working on universal optimizations.

We work closely with developers who are our partners like Audirvana to bring the most satisfying experience to our clients with optimizations on Nimitra. The change of direction to universal approach will optimize all audio applications.

 

Core Isolation Policy:

Single core (Recommended for low latency audio playback)
Dual cores (Recommended for high buffering audio playback)
No isolation (Disabled)

Playback Optimizations:

Standard optimizations (Default recommendation)
Enhanced optimizations (Improve playback performance)
Max optimizations (Full real-time process optimizations)
Safe optimizations (Improve Roon’s reliability)
Extra-safe optimizations (Fail-safe optimizations)
No optimizations (Disabled)

 

Default configuration will use dual core isolation and standard optimizations now to maintain good synergy and reliability with most devices. Customers can also request for optimal configuration for their system to get the best sound quality possible.

 

Improved reliability with Roon/JRiver Optimizations

 

 

After releasing firmware 5.0, we noticed a few unusual issues with Roon and JRiver software used in Nimitra and added workaround to resolve the following cases as below.

1. Roon keeps eating up space after applying a few updates so all temporary files will be cleaned up before loading Roon on startup
2. JRiver has occasional issues with USB audio not being responsive due to having pause on audio playback so it will stop after a long pause

Firmware 6.0 will address these issues and keep Nimitra stable with unusual cases but we do care enough to bring the best music experience.

 

Improved internal system and application optimizations

 

There’s a lot of internal system and application optimizations in firmware 6.0 to further improve audio performance in this release. Even Airplay now will bring outstanding audio performance and some application files are updated to more recent version.

More unused features in audio platform and operating system are disabled to further reduce interference in system and bring inner fidelity of streaming to the next level along with improved internal system optimizations.

 

Improved quality of life improvements based on ErawanOS

 

After releasing Erawan, there’re a few changes being requested by clients and store vendors to bring to Nimitra too. For example, changing track with JPLAY in Erawan will have smooth fade out before playing a new track. This is implemented in firmware 6.0 too.

Some other unique optimizations from Erawan are also implemented on Nimitra such as disabling core parking and USB’s power saving features so Nimitra will improved sound quality and user experience being more similar to Erawan for what Nimitra can achieve.

 

Changelog

-Added Audirvana/Spotify/Tidal/Qobuz applications support into NimitraOS optimization platform
-Added I/O priority optimization on Audirvana/CoreAudio engine/Roon/Windows Audio
-Added JRiver’s memory playback mode decoding file into memory before playback
-Added temporary files cleaning process to maintain product’s reliability over time
-Added Windows Server 2025 sound quality optimization into NimitraOS
-Changed JRiver’s latency optimizations to Core latency optimizations supporting FidelizerRemote / uPNP / OpenHome / LMS
-Disabled Cloud content delivery that may download over time and cause “Get even more out of Windows” screen
-Disabled CPU core parking and USB’s power saving features
-Disabled un-used features in core streaming platform to improve performance (can re-enable requested feature via remote support)
-Extended core isolation and playback optimizations to all supported features including Audirvana and HQPlayer NAA endpoint not just Roon
-Improved .NET runtime optimizations for better performance and reliability
-Improved compatibility with JPLAY iOS app
-Improved disabling Windows Update in more cases (Windows Update can affect sonic performance and remove optimizations)
-Improved internal sound quality optimizations for NimitraOS 2.0 platform
-Improved optimizations on WDM audio performance (DirectSound, Airplay, audio in browser, etc.)
-Improved reliability of automate library files scanning
-Improved reliability of Roon updates
-Improved reliability of uPNP / OpenHome / LMS features
-Improved reliability with JPLAY iOS app in some cases
-Improved Roon Isolation Policy optimizations for better sound quality and stability
-Improved Roon performance by cleaning temp/cache before running RoonServer
-Improved startup optimizations for better sound quality and reliability
-Optimized Airplay streaming quality to improve audio performance
-Optimized core streaming platform’s audio output buffering to improve compatibility with JPLAY streaming app
-Optimized default configuration to improve performance and reliability with legacy USB DACs and USB storage playback
-Optimized remote support reliability to reduce its effect to audio processes without affecting performance
-Updated AirPlay platform binaries to stable version
-Updated core streaming platform to be recognized in streaming app as Nimitra endpoint
-Updated HQPlayer NAA binaries to version 5.1.5
-Updated OpenHome libraries to latest stable version

 

If you’re using Nimitra Classic, I’d like to inform that Nimitra Classic will be discontinued in future after successful launch of CoreStream streamer. So, you can upgrade your Nimitra Classic to Nimitra2 at $1,500 USD only.

Nimitra runs on specially tuned NimitraOS platform with special version of Fidelizer. All these optimizations are specially tuned for Nimitra’s hardware and software configuration, separated from Fidelizer software optimizations.

Nimitra Classic / Nimitra / NimitraS / Nimitra2 customers can send request for firmware update and I’ll update Nimitra firmware through remote or request download link for applying update manually.

 

 

After releasing Nimitra2 with improved hardware modification, I’ve been optimizing Nimitra2 to improve sound quality with new standards. With new VRDS ATLAS transport from Esoteric K1X Grandioso, I finally brought Nimitra2 to masterpiece level with firmware 5.0 update.

Version 5.0 will cover changes in various areas to improve sound quality and also reliability with better user experience. This is probably the biggest update since launching Nimitra 6 years ago. Here’s summarize about major updates in version 5.0 update.

 

Added Windows Server 2022 Sound Quality Optimizations

 

Many people said Windows Server sounds a lot better but personally I prefer sound signature from some Windows 10 builds more so I didn’t look into Server builds as much until this year. When I tried Windows Server 2022 this year, I was blown away by Windows Server 2022’s performance.

If we were to compare how Windows sounds as stock environment, Windows Server 2022 is no doubt the best sounding Windows. But I don’t think sound quality from Windows Server 2019 to 2022 will be improved with any major changes on system files so I tried to crack the secrets.

This year I spent a long long time researching on the difference between my favorite Windows 10 builds and Windows Server 2022. I compared all parts of registry and system configuration between these two and finally managed to crack the secret sauce of Windows Server sound.

The main reason why Windows Server sounds better is default configuration for Server version have some parts that favors sound quality better. I traced the changes and applied the applicable differences I found into NimitraOS and viola! NimitraOS sounded very similar to Windows Server 2022.

But it doesn’t end at just that. Some changes from Windows Server configuration are not for better sound quality. There’s difference ups and downs so I tried to implement bits by bits and adjust configuration for optimal sound quality.

After this long process of trial and error with listening test, I finally managed to integrated Windows Server 2022 configuration into NimitraOS with optimal sonic performance. At this point NimitraOS already has better sound quality than Windows Server 2022.

 

Added Roon Sound Quality Optimizations

 

 

Since Roon 1.8 update, I started using Roon more to discover new music with Roon Radio feature. It also sounds better than previous versions so I started taking Roon seriously and tried to find a way to make Roon delivering better sonic performance highend audio system.

After a long research along with Windows Server 2022 sound quality optimizations, I managed to to find a method to deliver highend audio performance with Roon. Roon has 3 main components which are:

RAAT: Managing audio streaming between devices
Core: Managing core features in Roon core
Appliance: Managing essential tasks like database and DSP

Understanding how each component works, I can optimize Roon in Nimitra with two main principles to improve sound quality:

Core Isolation: Nimitra has 4 cores so I can isolate Roon components into different cores. I still need Appliance to have all cores or Roon will be too slow.
Priority Optimizations: By increasing RAAT’s priority which involves handling audio transport directly so Roon can have better audio performance.

After testing out a few combinations, I managed to sort out Roon Optimizations with the following options below:

 

Roon Core Isolation Policy:

Single core (Recommended for low latency audio playback)
Dual cores (Recommended for high buffering audio playback)
No isolation (Disabled)

Roon Playback Optimizations:

Standard optimizations (For all media sources)
Local optimizations (For internal/external storage)
Streaming optimizations (For NAS/streaming services)
MQA optimizations (For MQA Core Decoder)
No optimizations (Disabled)

 

Default configuration will use single core isolation and standard optimizations. Customers can also inform about their system for applying firmware update with optimal configuration for their system to get the best sound quality possible.

 

Added JRiver Sound Quality Optimizations

 

 

After finishing Roon optimizations, I started working on my favorite platform JRiver to get better sound quality too. With custom tuning for lower latency, JRiver can deliver audio performance closer to live performance with zero latency jitter.

 

JRiver Latency Optimizations:

Ultra low latency (100ms)
Low Latency (200ms)
Standard (1000ms)
Reliable (2000ms)
Relaxed (4000ms)
Safe (6000ms)
No latency change

 

Default configuration will use low latency at 200ms which is stable enough for most cases. Technically it could as low as 50ms but such scenario can only be possible with non-highres format in highly controlled environment.

I also added “Enable pure playback (disable plugins in audio chain)” to be used by default since default configuration can use this feature. This will disable audio related plugins from audio chain completely for true pure playback.

JRiver platform also has improved FidelizerRemote web app supporting light/dark theme configuration and have better library browsing and playback control based on Roon UX too. You can access FidelizerRemote through http://nimitra_sn[written serial in sticker/box].local

 

Revised Sound Signature Profile optimizations

 

I used to offer two sound signature profiles but it’s no longer necessary with new finalized configuration based on Windows Server 2022 that can deliver the best of both worlds. In this firmware 5.0 update, Sound Signature Profile is now changed to options based on Fidelizer software as below.

 

Sound Signature Profile:

Natural harmonics with linear sound
Natural harmonics with rich details
Sharp image with linear sound
Sharp image with rich details

 

Default configuration will use “Natural harmonics with linear sound” option based on Esoteric CD transport as reference. They’re tuned slightly different from Fidelizer for optimal sonic performance with NimitraOS platform and hardware.

 

Improved NimitraOS core sound quality optimizations and quality of life improvements

 

Besides Windows Server 2022 / Roon / JRiver optimizations, NimitraOS also has internal optimization improvement too. I added .NET Framework performance optimizations to improve performance and sound quality with Roon. Some internal configuration are optimized for better sound quality and reliability.

I also updated OpenHome/NAA libraries with improved configuration too. If you use OpenHome feture with Linn/Kazoo/Lumin/Sound Stream app, please inform support during update.

 

Changelog

-Added .NET Framework performance optimizations to improve performance with Roon
-Added JRiver’s latency optimizations to improve sound quality on JRiver’s based platform (FidelizerRemote / uPNP / OpenHome / LMS)
-Added JRiver’s pure playback mode disabling plugins in audio chain completely
-Added Roon optimizations features with core isolation and priority optimizations options
-Added Windows Server 2022 sound quality optimization into NimitraOS
-Improved JRiver audio output configuration for better sound quality
-Improved internal optimizations for better performance and reliability
-Improved internal sound quality optimizations in NimitraOS
-Improved reliability of OpenHome streaming in Lumin/Kazoo app
-Improved compatibility with remote support feature
-Increased hardware detection timer to look for changes after 60 seconds
-Updated FidelizerRemote UI to support light/dark theme with revamped UI
-Updated HQPlayer NAA binaries to latest stable version
-Updated OpenHome libraries to latest stable version

 

Nimitra runs on specially tuned NimitraOS platform with special version of Fidelizer. All these optimizations are specially tuned for Nimitra’s hardware and software configuration, separated from Fidelizer software optimizations.

Nimitra/NimitraS customers can send request for firmware update and I’ll update Nimitra firmware through Teamviewer or request download link for applying update manually. This update is highly recommended for all Nimitra users.