XISRC – SAMPLE RATE CONVERTER
XiSRC is a high quality software Sample Rate Converter to optimize your audio files for playback by adapting the sample rate and bit depth. High precision conversion algorithms ensure a perfectly preserved audio integrity.Add to cart
- Windows 7 – 10 / 32 & 64 Bit
- Mac OSX Lion 10.7.3 – Sierra 10.12.x
Flat or Noise Shaping Dithering for 32 & 24Bit to 16Bit conversion
DSD to PCM Converter
PCM to DSD Converter (High Quality Sigma Delta Modulator)
Better than -200dB THD+N (Total Harmonic Distortions + Noise)
Peak normalization if the source file contains Inter Sample Peaks
64Bit High Precision Audio Engine
Bit Depth for Input and Output: 1, 16, 24 und 32Bit
Output Audio Formats: WAV, AIFF, FLAC and DSD
Input Audio Formats: WAV, AIFF, FLAC, ALAC, DSD and MP3
Supported DSD Sample Rates: DSD64, DSD128, DSD256 and DSD512
Supported PCM Sample Rates: 44.1, 48, 88.2, 96, 176.4, 192, 352.8 and 384 kHz
Metadata transfer (album, title, artist, cover, etc.) between all file formats that include metadata
Multi-Threading to allow the conversion of several audio files in parallel
Batch processing with freely configurable output file names
The Test Version is limited to one minute output file length
The activation key allows three parallel installations (Windows & MacOS X)
XiSRC can be fully tested before purchase. Only the output file length is limited to 1 minute.
The activation allows 3 parallel installations. In fact, it is possible to use the Windows and MacOS X Version in parallel by just using one activation key.
WHY DO I NEED A SAMPLE RATE CONVERTER?
BUT WHAT IS SO SPECIAL ABOUT A SAMPLE RATE CONVERTER
Converting the sample rate within the same sample base is pretty straightforward. If we want to convert from 44.1 kHz to 88.2kHz then we just need to double the sample rate.
Well, it is not really that easy because the algorithm needs to filter the signal, after it has been stuffed with zeros, to reject images within the spectrum.
It becomes even more complex if we want to change the sample base from 96kHz to 44.1kHz. To do it in the right way we have to up-sample by a factor of 147 and afterwards we must apply a down-sampling by 320 (96kHz x 147/320 = 44.1 kHz). Such a processing involves different up- and down-sampling steps with several low pass filters involved.
XiSRC uses a 64Bit high precision audio engine to make sure that the numerical rounding errors, introduced during thousand of multiplications within the filters, are well below the signal level. The noise floor of a 64Bit number is at around -384dB that is far below the -192dB quantization noise of a 32Bit audio signal.
But now comes the next challenge. We must change the bit rate from 64Bit to 32, 24 or 16Bit. If we just truncate the excessive bits then we get something called quantization noise. This is really ugly because of the none-linear and signal correlated nature of quantization noise it creates harmonic distortions audible during faint parts of the music.
Luckily there is a mathematical trick to decorrelate the noise from the signal by just adding further noise to it before it gets truncated. That method is called “Dithering”.
There are different kinds of Dithering, but we decided to implement “Flat Dithering” and “Noise Shaping”.
Noise shaping is a feedback process where the small errors between the original and the truncated signal are fed back into the process to shape the quantization noise in a way that it decreases for important frequencies but increases for less audible frequencies (e.g. above 10kHz at a 44.1kHz sample rate).
WHY SHOULD I USE XiSRC AND HOW DOES IT WORK?
XiSRC provides great usability and quality by applying extreme precise algorithms for a very affordable price.
The key features of a THD+N better than -200dB, advanced Dithering Modes, 32Bit support and fast processing by using a 64Bit High Precision Multithreading Audio Engine are huge advantages of the XiSRC Sample Rate Converter. Additionally XiSRC uses several Threads/CPU-Cores to increase the conversion speed.
Six easy steps to convert your audio files:
Drop your audio files into the batch processing list or use the “Load Dialog” to select one or multiple files
Select the Target Sample Rate
Select the Target Bit DepthWe recommend to stay with the bit depth of the source material (No change) or to choose 24Bit.
Choose a Dithering Method if you do a bit depth reduction (32 & 24Bit -> 16Bit)In most cases “Flat” is a good choice, whereas “Noise Shaping” moves a part of the quantization noise from the audible into the less audible frequencies.
Select the output file format and folder
Press “Start” to initiate the conversion of the loaded audio files
XiSRC uses linear phase FIR-Filters. Therefore, the phase response is linear and does not influence the music signal.
There are a lot of controversy discussions whether the pre-ringing caused by linear phase filters is more audible than the coloration of minimum phase filters.
We did everything to keep the FIR-Filters as short as possible to minimize pre-ringing. Because Sample rate Converter filters work around the Nyquist frequency the pre-ringing impacts mostly the ultrasonic frequencies, mitigating the audible effect.
The current version of the XiSRC does not provide minimum phase filters but that could be an additional feature for upcoming versions to avoid any pre-ringing at the costs of introducing coloration due to phase shifts.
XiSRC shows the following pass band transitions with a maximum ripple of 0.01dB:
|Sample Rate [kHz]||Transition [kHz]|
XiSRC TESTSIGNAL MEASUREMENTS
We implemented an internal test signal generator to allow the verification of the XiSRC Sample Rate Converter at any time.
A right mouse click within the list opens a context menu. Selecting „Create Test-Signal“ opens a GUI where it is possible to choose between a sinus and sinus sweep. After setting all parameters (Sample Rate, Amplitude, Test-Signal Frequency and Target File Name) the test signal appears in the list, similar to any other audio file loaded. Finally, it is possible to convert the test signal into any sample rate or bit depth for further investigations with software like the MusicScope to verify the XiSRC performance.