Information

Our studio work is adapted to your music style, the type of use and the audio characteristics of the final media. If you are requesting a specific digital encoding, thank you tell us all the parameters of the desired format.

If possible, give sufficient time to the sound engineer so that he can work on your project in several times (especially for albums). This procedure allows to step back in order to best refine the sound processing.

Once the audio work realized, we will deliver the master files by downloading from our secure server (send by e-mail of a web link and an access code). After a full listening of each file, you will validate the masters or you will ask a change if necessary. Then, we will realize optional physical supports and send them by post.

Mastered for all digital platforms including iTunes Store:

Please read the technical instructions of the selected digital platform for selling your music online. If the platform encodes itself the file to be downloaded, you must provide an uncompressed master (WAV 24 bit or WAV 16 bit). If it's necessary to directly supply the compressed file to be downloaded, use the encoded version included in each package (M4A/AAC 256 kbps or MP3 320 kbps). Our compressed files are optimized and have superior audio quality compared to a standard encoding performed with a free encoder. If you want a specific encoding not included in the packages (FLAC, Ogg Vorbis...), please add the "Additional Master" option.

Our masters respect the technical recommendations of the ITU, EBU and many digital platforms (including iTunes) in term of audio limiting (dB True-Peak). Audio peaks of the PCM master files (WAV) around -0.3 dB FS / -0.1 dB TP.

If you want to upload a master on iTunes Store, use the studio quality "HD Master 24 bit" file included in each package. The "iTunes Plus 256 kbps - 44.1 kHz" file reproduces the iTunes AAC encoding and allows an audio preview.

Learn more by reading the Mastered for iTunes technology brief by Apple: click here

In summary: "An iTunes Plus AAC file uses a sample rate of 44.1 kHz... If the sample rate of the source file is greater than 44.1 kHz, it's downsampled to 44.1 kHz... The encoders then use every bit of resolution available, preserving all the dynamic range of a 24-bit source file and eliminating the need for dithering..."

Special mastering for streaming (Loudness normalization):

Since 2012, Kilohertz is the French pioneer of mastering optimized for broadcast in loudness level with the implementation of international recommendations (ITU-R BS.1770) and European (EBU R128). These new standards define measurement methods and give audio level values to be respected. The technical recommendations from the AES (TD1004.1.15-10) supplement these documents for audio streaming.

It has now become useless to strongly limit a signal intended for online streaming because it's the sound intensity (intrinsic volume) that is taken into account for the broadcasting and the alignment of the tracks with one another. The volume of this streaming is much lower than that of a master of the "Loudness War" type. The sound quality can thus be improved by the use of a larger dynamic range. The attack transients and the variations of intensity of the source are preserved for a less crushed and more natural sound result. Spotify, Deezer, Apple Music, Tidal or YouTube use this principle of volume normalization, but each with their own parameters (function activated by default or not, different target volume...).

Currently, the measured average levels are as follows:

(I = Integrated Loudness / TP = True Peak / PLR = Peak to Loudness Ratio)

Spotify (normal): I = -14 LUFS / TP = -1 dB / PLR = 13

Deezer: I = -15 LUFS / TP = -1 dB / PLR = 14

Apple Music: I = -16 LUFS / TP = -1 dB / PLR = 15

Tidal: I = -14 LUFS / TP = -1 dB / PLR = 13

YouTube: I = -14 LUFS / TP = -1 dB / PLR = 13

 
As an option, or as the main choice, we offer masters specially optimized for audio streaming. These files are compatible with all online music listening services:
I = -14 LUFS / TP max = -1 dB / PLR = 13

Hi-Res, Studio or HD files:

Hi-Res, Studio or HD files (depending on the name) are always in 24 bit and at a sampling rate of 44.1 kHz or more.
 
We sometimes read that no one can hear any difference between a master at 88.2 kHz (44.1 kHz bandwidth) and a master at 44.1 kHz (22.05 kHz bandwidth) because the human ear usually does not exceed 20 kHz. So it's not necessarily that easy to hear, but it's wrong! The best results are obtained with a full processing at a high sampling rate: recording, mixing and mastering. And even with a downsampling to 44.1 kHz at the end of processing (thanks to the new SRCs with no measurable artifacts), there can be a very slight improvement in sound quality. Hi-Res is usually best enjoyed with classical music (full-scale symphony orchestra with the playing of the musicians and the acoustics of the hall). You really shouldn't bet everything on that, but there is an audible difference that will be more or less subtle depending on the case and the person...

Nyquist-Shannon's theorem states that the discrete representation of a signal requires evenly spaced samples at a sampling rate greater than twice the maximum frequency present in that signal. Sony and Philips decided to choose the 44.1 kHz sample rate for the Audio CD in 1979. This choice is the minimum for converters to interpret very high frequencies up to 20 kHz. The small margin above is intended for the low-pass filter that prevents hearing the spectrum aliasing at 22.05 kHz. The main advantage of sampling above 44.1 kHz is that the low-pass filter can be adjusted more gradually so that the sound becomes more natural and not dull. This can be audible on very high-pitched instruments, such as cymbals or synthetic sounds, because of the harmonics. The temporal resolution is related to the sampling frequency (f=1/T) and humans can distinguish time differences less than or equal to 2 μs. The time difference between two samples at 44.1 kHz is 22.68 μs, this may also not be accurate enough in some cases. The big disadvantage of sampling above 44.1 kHz is that the audio files are heavier.

Quantization is the action of quantizing an analog signal (in volts) into a digital scale. The number of bits represents the binary equivalent of the analog value of a sample: it is the precision of the encoding of the dynamics. In 16 bit, as for the Audio CD, there are 65'536 levels and 96.3 dB. In 24 bit, there are 16'777'216 levels and 144.5 dB of dynamic range. The transparency of a digital system increases with the number of levels. In a sound recording, the elements most affected qualitatively by low quantization are those of low level. A large dynamic range allows more nuances and therefore increases fidelity. But, again, audio files are heavier.

Here is a serious study from the Audio Engineering Society that presents an ABX test with 16 listeners. The conclusion is that, on the whole, the participants were able to distinguish between files recorded at 88.2 kHz and those recorded at 44.1 kHz: click here

ID3v2 metadata:

The delivered files (WAV, M4A, MP3) contain metadata in ID3v2 format. If you wish, thank you to provide us for each track the following information: title, artist, album, track number (position in set), music genre, year... and the album cover (picture file).

Since the ID3v2 version, the size reserved for the music genre is not limited and it's possible to specify what you want. The following music genres are defined in ID3v1 by a numerical value from 0 to 79 and can be used as a basis:

Blues / Classic Rock / Country / Dance / Disco / Funk / Grunge / Hip-Hop / Jazz / Metal / New Age / Oldies / Other / Pop / R&B / Rap / Reggae / Rock / Techno / Industrial / Alternative / Ska / Death Metal / Pranks / Soundtrack / Euro-Techno / Ambient / Trip-Hop / Vocal / Jazz-Funk / Fusion / Trance / Classical / Instrumental / Acid / House / Game / Sound Clip / Gospel / Noise / AlternRock / Bass / Soul / Punk / Space / Meditative / Instrumental Pop / Instrumental Rock / Ethnic / Gothic / Darkwave / Techno-Industrial / Electronic (Electro) / Pop-Folk / Eurodance / Dream / Southern Rock / Comedy / Cult / Gangsta / Top 40 / Christian Rap / Pop-Funk / Jungle / Native American / Cabaret / New Wave / Psychadelic / Rave / Showtunes / Trailer / Lo-Fi / Tribal / Acid Punk / Acid Jazz / Polka / Retro / Musical / Rock & Roll / Hard Rock

To learn more, please read the article on Wikipedia: click here

Here are the services offered in detail:

• Comments and suggestions on mixing and encoding of your source file.
• Mastering by digital and/or analog process of your source mix in stereo.
• Work depending to the style of music, the type of use (club, radio, high-fidelity) and the final support.
• Audio treatments depending on corrections/optimizations necessary and artistic choices: filtering, equalization, compression, reverb, spatialization, maximization, limiting, dithering...
• Optimization of each individual track and overall consistency in listening (EP / Album).
• Quality control and numerical analysis (modulation and peaks, sound level, balance between frequencies, phase of signals...).
• Finalization and delivery of master files (uncompressed audio formats) and preview files (lossy compressed audio formats).
• Verification by probing of each master file before uploading it on our server.

Notes: For the "Stereo Mastering" and "Stem Mastering" solutions the total time of a track is 7 minutes maximum. In addition, and depending on the duration, it is possible that we asked € 5 (VAT excluded) per additional minute. For orders over 25 tracks and special cases, thank you to contact us by message.

Same as the "Stereo Mastering" solution except that your source mix is in 3 stereo sub-groups (maximum) in order to rework in depth the sound. We can modify each stem (or sub-group, or track) in volume and in panoramic, and add specific audio processing (equalization, compression...). The stems are summed and the result is treated as a stereo mix (please read the "Stereo Mastering" information).

Same as the "Stereo Mastering" solution except that your source mix is in 8 stereo sub-groups (maximun) in order to rework in depth the sound. We can modify each stem (or sub-group, or track) in volume and in panoramic, and add specific audio processing (equalization, compression...). The stems are summed and the result is treated as a stereo mix (please read the "Stereo Mastering" information).

• Mastering by digital processing of your source mix in stereo (DJ Set / Mixtape).
• Finalization and delivery of master files (uncompressed audio formats) and preview files (lossy compressed audio formats).
• Verification by probing of each master file before uploading it on our server.

Notes: This solution is valid if the tracks are chained with a good continuity of volume and equalization (bass, middle and treble). The total duration must not exceed 78 minutes.

• Mastering by digital processing for alignment of your master sources in stereo.
• Finalization and delivery of master files (uncompressed audio formats) and preview files (lossy compressed audio formats).
• Verification by probing of each master file before uploading it on our server.

Notes: This solution is valid if the tracks to compile are "well mastered" and that the whole is sufficiently coherent. The "Stereo Mastering" solution will be applied to the tracks of lower quality. The total duration must not exceed 78 minutes.

• Added to the package price for an additional version of a track. The audio processing applied to the alternative mix is the same as the original version. For example: Radio edit, Extended mix, Instrumental version...
• Finalization and delivery of master files (uncompressed audio formats) and preview files (lossy compressed audio formats).
• Verification by probing of each master file before uploading it on our server.

• Added to the package price for an additional master of a track for a pressing on vinyl. This master is a file that is adapted for audio characteristics of vinyl record: dynamic, equalization, stereo...
• Finalization in PCM format for an analog use on vinyl record, default: WAV (PCM) - 24 bit - 44.1 kHz - stereo.
• Verification by probing of the master file before uploading it on our server.

Notes: A reference tone is provided for the alignment level with the vinyl pressing (separated file with a continuous frequency of 1 kHz at 0 Vu). The source for the vinyl version may be an alternative mix of different duration without additional cost. In this case, no need to add the "Alternative Version" option.

Added to the package price for an additional master of a track for streaming on Internet (YouTube, Spotify, Apple Music, Tidal...). This master is optimized and compatible with all online services: audio level at -14 LUFS and maximum peaks at -1 dB TP (PLR = 13).

Finalization in PCM format for digital use (web streaming), default: WAV (PCM) - 24 bit - 44.1 kHz - stereo (with ID3v2 metadata including cover, if such information is provided).

Verification by probing of the master file before uploading it on our server.

Note: The source for the Streaming version may be an alternative mix of different duration without additional cost. In this case, no need to add the "Alternative Version" option.

• Added to the package price for an additional master of a track for a TV broadcasting. This master is a file that is adapted to the recommendations of the EBU: audio level at -23 LUFS, maximum peaks at -1 dB TP...
• Finalization in PCM format for digital use (TV, video ...), default: WAV (PCM) - 24 bit - 48 kHz - stereo (with ID3v2 metadata including cover, if such information is provided).
• Verification by probing of the master file before uploading it on our server.

Note: The source for the TV version may be an alternative mix of different duration without additional cost. In this case, no need to add the "Alternative Version" option.

Added to the package price for a specific audio processing to reduce (or delete as appropriate) noises, crackles, hisses, clicks and other interferences.

Note: This option is valid in the case of minor defects (some clicks or crackles, a little noise...).

• Added to the package price for an additional master in a specific digital format (file in a different encoding than those included in the package, with metadata if such information is provided): WAV, AIFF, MP3, AAC, WMA, Ogg Vorbis, FLAC...
• Verification by probing of the master file before uploading it on our server.

Note: Thank you to specify your request with a comment when ordering.

Added to the package price to place one additional index in a master file before Audio CD burning.

Example: For indexing a DJ-Mix with 10 chained tracks, it must be added 9 additional indexes...

Note: Thank you to specify your request with a comment when ordering.

• Added to the package price in order to duplicate Audio CDs in a pressing plant. This option includes the editing of the mastered tracks in the Red Book standard: with or without breaks between tracks (silence), maximum total duration of 74 minutes with breaks (up to 79 minutes depending on the pressing plant), PQ codes, ISRC, UPC/EAN (barcode), CD-Text...
• Finalization in DDPi format (Disc Description Protocol image).
• Realization of a "DDPi.zip" file (with all the information) for the pressing plant.
• Downloading of a DDPi player for control so that you can check the DDP image of the CD before it is pressed and duplicated. You will also receive a full report in PDF format (track titles, breaks, durations, ISRC, UPC/EAN, CD-Text...).
• Verification by probing of the files before uploading them on our server.

Notes: Simply send an e-mail to the factory in charge of the pressing to transfer the link to the "DDPi.zip" file. The DDPi standard provides a quality transport: it's reliable, secure, fast and free compared to burning a CD that must be mailed.

• Added to the package price in order to duplicate Audio CDs in a pressing plant. This option includes the editing of the mastered tracks in the Red Book standard: with or without breaks between tracks (silence), maximum total duration of 74 minutes with breaks (up to 79 minutes depending on the pressing plant), PQ codes, ISRC, UPC/EAN (barcode), CD-Text...
• Finalization in DDPi format (Disc Description Protocol image).
• Realization of a DDPi Master for the pressing plant ("DDPi.zip" file on our server, or burning to Data CD).
• Burning of an Audio CD control for you generated from the DDPi Master.
• Printing of the full burning report (track titles, breaks, durations, ISRC, UPC/EAN, CD-Text...).
• Verification by probing of the media.

Note: Remember to add the "Postal Shipping" option to ship physical media.

• Added to the package price in order to duplicate Audio CDs in a pressing plant. This option includes the editing of the mastered tracks in the Red Book standard: with or without breaks between tracks (silence), maximum total duration of 74 minutes with breaks (up to 79 minutes depending on the pressing plant), PQ codes, ISRC, UPC/EAN (barcode), CD-Text...
• Realization of 2 identical Audio PMCDs (Pre Master Compact Disc), 1 for the factory, 1 for you.
• Printing of the full burning report (track titles, breaks, durations, ISRC, UPC/EAN, CD-Text...).
• Verification by probing of the media.

Note: Remember to add the "Postal Shipping" option to ship physical media.

• Added to the package price in order to duplicate Audio CDs in a pressing plant. This option includes the editing of the mastered tracks in the Red Book standard with the additional data provided by you (photos, videos, texts...): with or without breaks between tracks (silence), 700 MB maximum per CD for audio and data, PQ codes, ISRC, UPC/EAN (barcode), CD-Text...
• Realization of 2 identical Extra PMCDs (Pre Master Compact Disc), 1 for the factory, 1 for you.
• Printing of the full burning report (track titles, breaks, durations, ISRC, UPC/EAN, CD-Text...).
• Verification by probing of the media.

Note: Remember to add the "Postal Shipping" option to ship physical media.

• The source files and master files on a Data CD 700 MB or a Data DVD 4.7 GB (depending on the total size of the files).
• Verification by probing of the media.

Note: Remember to add the "Postal Shipping" option to ship physical media.

• Added to one of the "Burning" options for an additional media (audio or data, CD or DVD depending on the total size of the files): DDPi, PMCD, Extra-PMCD, Data CD, Data DVD.
• Verification by probing of the media.

Notes: Thank you to specify your request with a comment when ordering. Remember to add the "Postal Shipping" option to ship physical media.

The physical media corresponding to the "Burning" options are mailed in a protective envelope with shipment tracking. The option includes the shipping of all media if there are several. The delivery time in France is 48 hours. For faster sending, or depending on the destination, the price may be increased.