I know you are all starting to get bored hearing about my Zen...
I messed with resistors last night. I changed R1 to .22, but changed it back. I wasn't happy with the amount of heat generated by the p-channel.
I started to change R11. I increased to from 3.3K in increments up to 15K. At 15K I'm getting about 54watts into 4ohms! It starts clipping at about 2.5V input. The problem is, I think my pre-amp doesn't handle it very well. When I turn on the other amps they pop my speakers. And when it runs the test tones, when it switches between each speaker, there is a pop out of all the speakers. But, it's now able to keep up with my mains.
I checked the input impedance and it's 154K. Which doesn't sound right. I might buy 15.4K. My meter was acting a little strange. It's 15 years old, so I'm used to it.
So, I need to decrease that resistor to an acceptable level. So, what is an acceptable level? What's the maximum input impedance I should see? 4.75K seems to be the industry standard. But, I'm sure that is not an absolute.
Does anyone see another way to balance R11 and R10 to lower the input impedance, but keep the same gain? I left R10 at 1K. I think maybe I'll buy a couple pots to mess with this more rapidly.
Thanks guys. Don't give up on my yet. I'm almost happy!
pixie
I messed with resistors last night. I changed R1 to .22, but changed it back. I wasn't happy with the amount of heat generated by the p-channel.
I started to change R11. I increased to from 3.3K in increments up to 15K. At 15K I'm getting about 54watts into 4ohms! It starts clipping at about 2.5V input. The problem is, I think my pre-amp doesn't handle it very well. When I turn on the other amps they pop my speakers. And when it runs the test tones, when it switches between each speaker, there is a pop out of all the speakers. But, it's now able to keep up with my mains.
I checked the input impedance and it's 154K. Which doesn't sound right. I might buy 15.4K. My meter was acting a little strange. It's 15 years old, so I'm used to it.
So, I need to decrease that resistor to an acceptable level. So, what is an acceptable level? What's the maximum input impedance I should see? 4.75K seems to be the industry standard. But, I'm sure that is not an absolute.
Does anyone see another way to balance R11 and R10 to lower the input impedance, but keep the same gain? I left R10 at 1K. I think maybe I'll buy a couple pots to mess with this more rapidly.
Thanks guys. Don't give up on my yet. I'm almost happy!
pixie