How Do Audio Transformers Work?

Simply, audio transformers work by:

• Stepping up or stepping down signal voltage
• Raising or decreasing a circuit’s impedance
• Converting unbalanced and balanced circuits
• Blocking DC current when permitting AC current
• Separating one audio unit electrically from another

Here are more detailed steps about how audio transformers work:

1. When an AC signal is applied to the audio transformer’s primary input winding, a corresponding signal appears on the output secondary winding. Since there is no direct electrical connection between these windings, the audio transformer isolates the input and output circuits between amplifiers and speakers (or other audio devices).
2. Depending on the turns ratio between the input/output wire coils, the passing applied signal is either increased or decreased. If the audio transformer has a turns ratio of 1:1, it isolates the primary circuit from the secondary side. The turns ratio is determined by the number of coils on the primary side (Mp) and on the secondary side (Ns). Note, an audio transformer may have several windings on each side.
3. Different input/output impedances are balanced between loads and amplifiers to achieve maximum power transfer. This is done as audio transformers give their impedance ratio value from one winding to another by squaring their turns ratio. There are other methods of doing this, depending on the audio devices being used.

Digital audio transformers reduce distortion, give ultimate sound balance, and provide a full range of high-quality audio sound.

3 Types of Audio Transformers

A basic idea of how audio transformers work isn’t all you need to know about them—you also need to know there are three different types of audio transformers to choose from, depending on the industry and use case scenario:

1. Audio input transformers  
2. Audio output transformers
3. Isolation transformers (can be used when the amplifier circuit has special requirements)

Typically, the working frequency of an audio transformer is between 10Hz and 20000Hz.

How to Get the Audio Transformers You Need 

There are two ways to get the audio transformers you need for your project’s application—purchase off the shelf or custom design and contract manufacture.

Purchase Off-the-Shelf Audio Transformers

Digital audio transformers can be purchased off the shelf from a trusted expert who can show you the right product for your application. Schott Magnetics has a huge variety of options in our catalog, ready to go. 

Custom Design and Contract Manufacture Audio Transformers

Many of our clients come to us with their own custom transformer design in hand, already knowing the exact specifications required for their application. We work with them to perfect their design and contract manufacture their audio transformers according to the highest standards of quality while remaining within their budget. 

With 70+ years of experience, Schott can offer the flexibility to choose the operating model that best suits your needs, either full turnkey manufacturing or labor cost-based assembly. 

Contact us to get started!