Colin151
03-02-2012, 15:23
Was wondering if any might have any ideas on this issue?
I just got inside my Lumley ST70 and am looking at the output transformers. I want to change the output impedance setting to 4 ohms (its now set on 8 ohms).
There are four connections coming off each output transformer. One is labelled "8", one "4", another "4" and another "C". The two labelled "4" have a jumper connecting them . Currently the one labelled "8" is connected to the speaker +ve terminal, and the one labelled "C" is connected to the speaker -ve terminal.
I am not sure what to do, - obviously I need to disconnect the 8 and likely put that on the tap labelled "4" next to it, but do I leave the other connect labelled "C" as it is? And what do I do with the jumper - connect it between the other 4 and the 8? Perhaps I don't need the jumper I'm not sure. If anyone had any ideas it would be much appreciated. Attached is a pic of one of the output transformers.
I just got inside my Lumley ST70 and am looking at the output transformers. I want to change the output impedance setting to 4 ohms (its now set on 8 ohms).
There are four connections coming off each output transformer. One is labelled "8", one "4", another "4" and another "C". The two labelled "4" have a jumper connecting them . Currently the one labelled "8" is connected to the speaker +ve terminal, and the one labelled "C" is connected to the speaker -ve terminal.
I am not sure what to do, - obviously I need to disconnect the 8 and likely put that on the tap labelled "4" next to it, but do I leave the other connect labelled "C" as it is? And what do I do with the jumper - connect it between the other 4 and the 8? Perhaps I don't need the jumper I'm not sure. If anyone had any ideas it would be much appreciated. Attached is a pic of one of the output transformers.