Hello,

If I need to replace the stock preamp tubes in the Origin 20 H, what is the exact model.

It show ECC83H and I think they are Shuguangs but not sure. They used to be Marshall branded Shuguangs or JJ but these have nothing written on it except ECC83H. Looks chinese but they sound best I think to nail that JCM-Plexi tone of the Origin. I tried other and it is a slightly different sound. I need to know the exact model.

Thanks