Electrocompaniet ampliwire bias adjustment

[legarem]

I recently bought an ampliwire last month. I really don't know what model it is because I only see Ampliwire written on the front.

I looked at the bias and Dc output ajustments. For each channel, I have 90mv across each (4) big 3W (.22 ohms)resistors that goes to output transistors. v+ and V- for the output stage are +31 V and -31V

Is 90mv inormal across the .22 resistors ?

Can you identify this model ?

I'm also tempted to bypass the input capacitors. Good idea ?

Thanks a lot

 

[lineup]

0.09 V / 0.22 Ohm gives = 0.04 Ampere
40 mA is very normal value.

 

[diy guy]

Bias adjustment

Hi

The bias should be 10-15mv on the 0.22 resistors which be

45 mA to 65 mA per device. The 90 reading is too high.

Tks

 

[legarem]

it seems that nobody adjusted the bias in this amp so I presume that it is working like it is since a long time.

If I keep it at 90mv across the .22 ohms resistors, it should work more in class A so the sound should be better . Right ?

What model do you think it is ?

Thanks

 

[legarem]

if 90 mv gives 40 ma

15 mv should give 6.66ma


6.66 ma appears low

 

[rollo22]

Hi

I received this info from Electrocompaniet for AmpliWire 65 (65 Watts):

bias 40mV when resitor value 0,47ohm
bias 20mV when resitor value 0,20ohm
adjust with R17

DC as close as possible to 0mV, measured on open jumper jp1
Adjust wth R3

hope this helps

Rollo