How to prepare files for mixing and / or mastering?


When submitting your files, please provide me with comprehensive mix notes in regards to the production details, mixing effects, and reference songs. I accept WAV files at either 44.1kHz, 48kHz, or 96KHz, ensuring all tracks begin from bar one, are of the same length, format and sample rate. In addition, please disable the ‘NORMALISE’ option for export if available in your DAW. Tracks can be submitted in either mono or stereo.

I kindly request that you provide the multi-track files in a dry state, free from effects like reverbs or delays as well as EQs and compressors. However, if you believe that any specific effects, processing, or creative elements (such as filter sweeps or delays) are integral to the sound, please ensure to include clearly labeled ‘Dry’ and ‘Wet’ versions of your track upon project submission. For vocal tracks tuned with MELODYNE or AUTOTUNE, please have the pitch correction processing printed into the vocal tracks, and feel free to share both “Raw” and “Tuned” versions. In the case you have MIDI or Virtual Instruments in your session, please export them as audio files, as I do not accept MIDI files for mixing, unless you make an explicit reques to replace certain virtual instruments, which would incur additional production charges.


For stereo mastering I would kindly ask you to deliver the following files:
– Full Mix (32bit or 24bit .WAV file)
If your song contains explicit content, please provide both Explicit and Clean version of the mix.
– Backing Track (32bit or 24bit .WAV file): in order to receive mastered backing track
– Instrumental (32bit or 24bit .Wav file): in order to receive mastered instrumental

For stem mastering I would kindly ask you to deliver 24bit .WAV stems tailored for your pfoject. The maximum true peak of any file must not exceed 0dB.


As part of the submission process, I would kindly ask you to clearly labeled your files. Additionally, I would greatly appreciate avoiding the use of ALL-CAPS to ensure a more organised and professional presentation.

Your files should be in a folder which name contains:

– Artist name
– Song title
– Tempo of the song
– Date of upload

How does the review process work and what files will I receivve?

You will be able to review the final mix and / or master as well as all subsequent revisions through a private link with an audio player that grants access to lossless, full-resolution WAV files. Following the acceptance of the final mix and / or master, you will promptly receive all relevant files, as specified below.

For mixing service, you will receive the following mix versions:
– Full mix (32bit .WAV)
– Instrumental (32bit .WAV)
– Backing track (32bit .WAV)

Please be aware that mixed stems will not be provided for assembling the mix. The intricate use of shared effects, shared parallel compression, and complex mix bus processing makes it impractical to recreate the exact mix from individually exported stems. If you require an additional mix version beyond the package I deliver, a nominal charge of £8 per additional mix version will apply.

For mastering, or mixing + mastering service, you will receive following masters:
– Streaming (24bit .WAV)
– CD (16bit .WAV)
– Instrumental and Backing Track (24bit .WAV)
– MP3
– DDPi format (if requested)

What are the payment terms?

All ‘mixing’ and ‘mixing + mastering’ requests are priced individually. For mastering pricing, please refer to Upon providing all essential details about your project, I will promptly give you with a final quote. Once I assess your files, depending on the service you hire me for, you will receive an invoice. Full payment must be made upfront before I commence any work. Please note that payment is accepted exclusively via Direct Bank Transfer.

In case you require more than 2 revisions, which are included within the price, I will happily continue working on your project, subject to an additional charge of £15 for each subsequent ‘mixing’ and ‘mixing + mastering’ revision, and £10 for each subsequent ‘mastering’ revision. 

Please be aware that returns and refunds are not applicable.

What happens if I loose my files?

You accept the responsibility for storage and archiving of all mixes, masters & any other files as well as the source materials once a project has been approved and files have been delivered. I will endeavour to store backup of all sessions, final mixes and masters, but I do not provide a guaranteed archival service

How do I credit your work?

Under my terms and conditions, you are obligated to provide the appropriate credit in association with any CD or other record that I have recorded, edited, produced, mixed, or mastered. The prescribed credit scheme is as follows:

Engineering / Editing / Production / Mixing / Mastering / Other: (choose the applicable)
Krzysztof Kessler

Additionally, appropirate credit must be included in the YouTube video description, the credits section of all applicable streaming services (where possible) and a suitable place in the inner sleeve liner notes of the CD or record. This credit should be presented in the same size, typeface, and font as any other similar information included in said liner notes.