help to set dc offset to threshold s450


2013-02-26 9:32 am
hi to all forum member i need our help to set the dc ofset of treshold s450.

i have purchased it used but in a right channel i read 1,2v dc and left channer i read -1,3 volts dc.

i nned also the schema or servece manual to teterminare the trimmer that regulate it.

i wait soon our help

thanks at all in advance and exluce me to my little english

i am italian



2013-02-26 9:32 am

following pictures


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to help me to determine which iteration of front end you have in that amp,read to me type of that 6-legged small metal transistor (on first pic)

then I can try to find schematic to point you in right direction

however , what you'll certainly need is to do some maintenance - for what you need to make front end pcb accesible

when you make that ,take few frontal pictures of pcbs and post them - so we can see is there need for changing small electrolytics and anything else

btw. pot you have on pcb is for setting Iq - standing current

you have appropriate info (pdf file) for that here : Treshold Treasure ?? while Papa was there : 400A | Zen Mod Blog

but , prior to that , you need to solve offset issues