Audio Transformers for Guitar Valve Amplifiers
In the meanwhile there are over a dozen manufacturers or component dealers, who are selling "Replicas", "Clone" or "...Style" transformers for guitar amplifiers. Precise datas, except the primary and secondary impendances for ouput transformers or the no load voltages for mains trasnformers can´t be found. Sometimes you can believe, that the are offering a copy from a "Clone" of a "Clone".
As you can see in a very nice way, I´m owing a lot of old and very important, original mains- and output transformers, so that you can be shure, that every copy is made from my own original.
The exact copy of a mains transformer of a guitar amplifier is as important as it would be for an output transformer, because the "sag" has a great influence to the soud of your amplifier. The total losses of the mains transformers together with caps and the rectifier determine the impendance of the power supply. The greater this impencance the more the voltage drop between no and full load would be. The score is a "compression" of your amplifier´s sound and a clean copy of the mains transformer is doing that again as it has does before.
One more, but an other important point too is the winding technology of the transformer itsself. As you can see at an output transformer of an Orange OD 120, there wasn´t used a bobbin with flanges at both sides. In cause of missing these flanges as an isolation to the beside core, you have to choose the side margins of the coil much bigger to prevent spark overs
This gives you a complete different geometrically design of the coil which makes it impossible to transfer it to 100 per cent onto a moulded or SRBP bobbin. The same thing applies vice versa too.
There are so many trivia you have to pay attention for at the assembling of clones from the original. The use of quality annealed laminations like the originals do, the right winding arrangement and a special in house anneling for aging the laminations. But these are only three points of much more.Auf den nachfolgenden Seiten werde ich Ihnen einige bildliche Orietierungsbeispiele geben, an denen Sie zumindestens von außen gewisse Merkmale des Transformators erkennen können.