transformers?

[atma]

on occasion i've heard people mention that the transformers in outboard gear can play a role in the perceived warmth or coloration in the sound of that unit. can someone explain this to me? i'm admittedly naive when it comes to hardware components, so i don't even understand what the function of the transformer is, or how it affects the sound of any gear it's a part of.

[DAS]

What is a transformer?

http://www.sweetwater.com/insync/word.php?find=Transformer

As for the sound...it's a little tricky to explain. Electrical energy is converted to magnetic energy and back again. This type of transformation (no pun intended) has various properties and idiosyncrasies that result in certain non-linearities in the signal, i.e. distortion.

Transformers cause varying degrees of distortion, of a type that many audio enthusiasts find appealing. Additionally transformers also do a great job at preventing several other problems that can potentially plague your audio chain, and thus can cause certain improvements in signal transfer under some conditions.

In the old, old days all audio I/O was handled via transformers, which A) resulted in a lot of qualitative development years ago, and B) resulted in a lot of engineers getting used to their sound, which naturally leads to some of them not being entirely comfortable parting with those characteristics.

[dpd]

^^^ Some correction required, IMHO:

Electrical and Magnetic energy are vestiges of the same thing - current moving through a wire sets up a magnetic field around it. Electromagnetism is one force, not two.

It's not intuitive, but it's the electromagnetic field that contains the energy. The coils in the transformer set up and focus the magnetic portion of those fields. How the input and output coils are constructed and aligned give a transformer its properties.

Transformers are linear devices in theory. Any distortion coming from a transformer is due to its construction and/or use. Some pleasurable sounding, some not.

A lot of transformer 'sound' is simply due to poor circuit designs interfaced to the transformer resulting in linear distortions (amplitude and phase errors/filtering over the audible bandwidth) and non-linear distortions(harmonic) due to magnetic saturations caused by overdriving it.

[DAS]

Originally posted by dpd
^^^ Some correction required, IMHO:

Electrical and Magnetic energy are vestiges of the same thing - current moving through a wire sets up a magnetic field around it. Electromagnetism is one force, not two.

Yes, but this was not important to get the "basic" understanding (which I think is what was needed here), only confusing in my opinion. Nevertheless this is indeed correct - two sides of the same coin so to speak.

As for the rest...a transformer is one of those things that, in theory, should be 100% transparent, but in practice isn't for many reasons, some of which are mentioned here.

"The difference between theory and practice is that in theory there is no difference."