Multiple Master is a meanwhile outdated font format. It ceased being relevant over 10 years ago. Its key advantage, the ability to embed font variations in a single file, will be available in OpenType fonts, probably from 2017 onward.
The Multiple Master font format is a variation on the Type 1 font format. Like Type 1 fonts, Multiple Master fonts are outline fonts: changing their size does not affect the output quality. Multiple Master fonts have, however, a unique advantage over regular Type 1 fonts: they offer users the freedom to create an unlimited number of variations of a font. Instead of having to use a font in a fixed number of variations, usually based on weight (e.g. light & heavy), style (e.g. italic) or width (e.g. condensed & wide), a user can specify his own variations within Multiple Master fonts. These variations are called instances.
Creating instances is done by modifying the font along one or more design axes. So if a Multiple Master font allows a user to define the width, this width can be changed and adapted to the layout. Users do not have to do these modifications themselves as MM fonts ship with a number of predefined instances. If a user wants to create another instance, this can either be done through a tool like Adobe Type Manager or directly within a limited number of applications. Some, like QuarkXPress and PageMaker, offer this functionality through the use of a plug-in (or xtensions as QuarkXPress users know them). Only Adobe Illustrator 7 and later have direct built-in support for Multiple Master fonts, allowing you to modify Multiple Master fonts using a simple slider.
The Multiple Master technology offers a number of advantages over other types of fonts:
- Custom-width fonts can help solve text-column justification problems. Spreadsheet applications generate custom instances of fonts to do a better job of fitting text into constrained areas.
- Graphic designers can create logotypes and advertising designs based on transformations and flexibility.
- Multiple Master fonts offer the ability to generate a version of a character that is optically correct for the size at which it will be viewed. In the age of metal type, character design and spacing were adjusted for the point size of the font. Smaller size fonts typically had proportionally wider spacing, heavier stems and serifs, and less contrast between thick and thin strokes than larger size fonts. With Multiple Master fonts, this refinement is also available in digital fonts. To accomplish this, the Multiple Master font must contain one set of outlines designed for use at small sizes and one for use at large sizes.
- Multiple Master fonts can be used to emulate typeface (that might not be present on the system or embedded in documents), provided the missing font’s metrics data are available. Adobe ships two Multiple Master fonts with Acrobat so missing fonts in PDF files can be emulated.
Multiple Master fonts can contain up to 4 different axes. Usually, one or two design axes are used. The most common ones are:
- Weight: from light to bold
- Width: from condensed to extended
- Optical size: from text font to display font
In some Multiple Master fonts, designers have used other criteria. One of the most famous Multiple Master fonts around is the ‘porn font’ MoveMeMM, created by Luc(as) de Groot. It gradually changes characters into erotic shapes and is a good example of the flexibility of the Multiple Master technology.
MM fonts on Macs running System 9 or earlier
ATM 3.0 and later support Multiple Master fonts. It comes with a small application called Font Creator which can be used to create new instances of Multiple Master fonts. This extra information is stored in one of the resources of the font.
On Macs fonts are stored in the Fonts folder, inside of the System folder. But if you are using a utility to access fonts, such as Suitcase or ATM Deluxe, fonts can be stored in any user-definable directory, or folder on your computer.
MM fonts on Macs running OS X
Mac OS X didn’t support Multiple Master fonts until release 10.2.3. From that release onwards, it is possible to install Multiple Master fonts but there aren’t any tools to modify them. That means the operating system can make use of the default instances of a Multiple Master font but you cannot generate your own instances using OS X. Mac OS X 10.4 is the last version I am aware of that can handle Multiple Master fonts.
MM fonts on Windows
MM fonts consist of 2 files: a file that carries the .pfb file extension and one with the .mmm extension which contains the font metrics data of the Multiple Master fonts.
On Windows computers the default directory for MM fonts is C:/psfonts.
Here is a summary on how various versions of Windows cope with these fonts:
- To use Multiple Master fonts under Windows ’95 and ’98, you need at least ATM 3.0. The ATM control panel can be used to create various instances of a Multiple Master font.
- Under Windows 2000, you need ATM (Lite or Deluxe) 4.1 (or later) to add support for Multiple Master fonts.
- More information on using Multiple Master fonts on Vista can be found on this page.
Outputting Multiple Master fonts
Unfortunately Multiple Master fonts can be quite difficult to output correctly. The main problem seems to be that when people send a job containing Multiple Master fonts to a printer or service bureau, they tend to include the original Multiple Master font but forget to include the instances they created of that Multiple Master font.
But even if you have the correct instances of a Multiple Master font, your system may still output text in Courier instead of the beloved Multiple Master font. In the days of System 7 or 8, switching PostScript drivers or deactivating the ‘unlimited downloadable fonts’ option in the Print-menu were well-known tricks to fix issues with Multiple Master fonts.
The future of the Multiple Master technology
The Multiple Master technology was no runaway success. Only a limited number of fonts have ever been released, the majority of them coming from Adobe. Late 1999, Adobe announced that it would no longer develop Multiple Master fonts. This was partially done because the company wanted to focus on OpenType fonts but the lukewarm reception of the Multiple Master technology and the lack of applications that supported it probably also played a role in Adobe’s decision.
The company kept selling their existing catalog of Multiple Master fonts until early 2003. At the end of 2004, Adobe stopped offering tech support for those fonts, excepting for customers who owned their Font Folio 9 library. Fortunately a tool like Transtype Pro can convert MM instances to OpenType fonts.
Today Multiple Master technology can be considered ‘dead’ but the basic idea behind it is making a comeback: version 1.8 of the OpenType font format includes Font Variations, allowing a designer to alter the weight, width, and another attribute of a single font. The 1.8 specifications were published in September 2016 and of course, it will take some time before such OpenType variable fonts become available and customization controls are included in popular design and layout applications.