Question: My amp guy told me that “core saturation” (overloading the transformers) was part of my amp’s distortion — and important to my tone. Is this true?
Answer: This is a popular misconception. You can irritate a tube to distortion — but the rules are completely different for trannys. Here’s why. Think of the musical signal that comes out of your electric guitar like the fuel you put in your car. Where does it go? It goes into the gas tank of course. The inductance of the output transformer is a lot like that gas tank. It holds the fuel and makes available as much as the engine demands. The engine’s ability to generate horsepower and torque can be severely limited by restricting the flow of fuel.
The same goes for your amp. Deep and tight bass notes, and how large the perceived soundstage your amp can deliver to, requires a lot of inductance to do the job properly. Undersized transformers and circuits designed to overload or saturate transformers won’t cut it. Inductance gets sucked out which converts your good tone into heat! So you not only get tonal loss but potentially shorter life expectancies from both your transformers and tubes!
You’ll know your amp’s trannys are being pushed beyond their operating capacities when you hear:
Make sure your amplifier is up to the task of delivering all the tone you demand with the proper output transformer installed. Don’t feel like you’re stuck with a poor sounding amp. There are many choices available to you from Mercury that will fix the problem. Buy the best and transform your uninteresting amp into a force to reckon with.
Technical explanation: Core saturation is the condition where the core material (usually iron) is completely magnetized. Any further increase in input energy will not produce an appreciable increase in magnetic flux. When this happens, the inductance of the coil is greatly reduced because no counter EMF is produced when theflux is unable to increase.
Source: https://mercurymagnetics.com/pages/_misc/FAQ.htm#Looking_for_Tone_in_all_the_Wrong_Places_
