Mixtape Nerd

In today's digital age, if you are serious about making analog mixtape, you probably have a good reason to commit to it. Much like other art forms (photographing, painting, singing, cooking ...), analog mixtaping offers staged experiences, from casual, retro enjoyment to deeply serious, meticulous craft. Over time, if your past mixtapes sound a bit off on upgraded systems or to discerning ears, it's possibly because the same work can be approached with varying levels of intention and care in the first place. Mastering digital audio for analog tape demands a delicate balance, accounting for not only what can be heard by ear but also the constraints of the medium itself — a skill that requires years of study, technique, and refinement. To assist people at various stages, providing a domain-specific tool can be more effective than spreading the know-how in words.

A typical mixtape workflow involves two major tasks: curating and remastering. Curating is about selecting and arranging audio programs to fit the tape's total length, often across both sides. Remastering ensures recording the audio programs within the given tape's allowed dynamic-range. In the past, equipment for remastering analog mixtape was complex and pricey. However, with the advent of the digital age, much of this can now be done on a computer using a digital audio workstation (DAW). But if you have done this a few times, you may find that using a general-purpose DAW may still be time-consuming — the workflow involves repeated manual operations with limited convenience/automation. If your passion for creating mixtapes hinges on tool efficiency, a dedicated software tool may better suit you.

Mixtape Nerd is a domain-specific app developed based on a series of "nerdy efforts" pursuing a streamlined mix-taping experience. It implemented a set of custom DSP engines for digital-to-analog mixtaping, hiding complex configurations behind a concise UI by pre-optimizing dozens of parameters for the intended purposes, and integrated everything altogether for maximum automation. The core idea was to significantly improve the initial success rate by measuring and planing in advance, rather than relying on the traditional trial-and-error method. Simply drag-and-drop audio files to start building a mixtape project. The app will pre-analyze each file and summarize its audio dynamics into a profile. Then, the app will be waiting for your input regarding what analog tape recording system you are going to use. Apparently, the app has no idea about brands and models, instead, it needs to know two numeric parameters, which are: (1) M.O.L. stands for maximum output level in decibels, and (2) S.N.R. stands for signal to noise ratio in decibels. It's a lille tricky to figure out the answers. You may have to temporarily work a bit harder out of the comfort zone. If you are really unfamiliar with these two terms, the app comes with built-in documentation showing a few ways of estimation. Specifically for using compact cassette tapes/decks, the app also provides a wizard for your convenience. Once you've got the MOL and SNR handy, you can tell the app by dragging the 3 sliders on the app's main meter, and then let the app generate a standard test tone for establishing a common reference level with the analog tape recorder under your supervision. The app will then automatically optimize all the audio programs to fit to the tape's capacity, including dynamic-range and time-length.

In the finishing stage. you can preview, test and refine the result in real-time, and fine-tune the settings if necessary. Upon completion, the mixtape project can be exported as a master audio file (per side) for offline duplication, with an optional auxiliary audio file which contains a reference test tone for calibrating the duplication system. Alternatively, a mixtape project can also be played directly with the app for real-time tape recording, optionally driving the sound card in exclusive mode for the shortest and cleanest audio path.

To use this app to its full potential, basic understanding of analog tape recording would be highly beneficial, e.g.: terms like "dB", "VU", "MOL"and "SNR", as well as "dBFS" and digital headroom... The app's core functionalities are designed around these concepts. The app comes with documentation, wizard, and online videos to ease the learning curve. Once you've picked up the new workflow, it will become effortless. But please be aware before acquiring the app.

Functionas and Features

Limitations:

Please note, this app is not a PRO grade tool by design, instead, it is a lightweight utility for audio enthusiasts who appreciate tape-based analog HiFi. Analog mix taping is a multi-factor optimization art, harmonizing objective rules and subjective preferences. Everyone has unique workflow and feature requests to suggest. Developing a universally accommodating software for serving such a task is a challenge, especially with limited resources. Hence, this app retains its commitment to being focused, concise and cost-effective, and steering clear of an overwhelming user interface akin to a spaceship's cockpit. Nevertheless, there might still be a bit of a learning curve to getting started. Especially for beginners, this app is merely a tool rather than a cookbook, having a basic understanding of analog tape recording beforehand would be of great help to overcome the initial learning curve.

Please also be mindful of the following technical constraints:

- Online streaming sources are not supported, unless pre-downloaded as local files.
- Items protected in the local Audio Library (e.g.: iTunes) are not supported.
- Tracks on LP, CD and tapes are not directly supported, unless digitized to local files.
- Acceptable audio file formats are: wav, flac, mp3, aac, m4a and ape, with standard stereo L/R channel layout, 44.1kHz ~ 192kHz, 16/24Bit.
- Preferred audio file location is the system designated "Music" folder, or otherwise explicit access permissions will be required repetitively.
- Works only with standard sound card with standard stereo L/R channel layout. Advanced PRO/Game sound cards may work but may require additional channel-remapping work pre-done at OS level.
- Exclusive sound card mode is currently in experiment and not guaranteed to work with any given sound card.
- Common DJ features are not included
   - No plugin interface.
   - No cloud sharing.
   - No beat match during cross-fade.
   - No graphic equalizer.
- Basic knowledge in analog tape recording would be required.

How to Install:
The software is being exclusively distributed via App Store or Microsoft Store.
The best way to download and install the app is to use the OS built-in "Store" app (such as "App Store" on macOS or "Microsoft Store" on Windows 10+). A registered user account with Apple or Microsoft will be required to start. Although a transaction can be finished outside of the Store, e.g.: via a Web browser, the actuall download/install should be completed by using the OS built-in "Store" app. So, it is recommanded to do all the procedures by using the "Store" app.

See also:
NAK T-100 (Audio Analyzer)
DDi Codec (for Dolby-B/C)
DxII Codec (for dbx-II/Disc)
DxI Codec (for dbx-I/Disc)

Short Introduction Video
Long Demo Video