The light bulb test is probably a false positive. The light bulb glows brightly at a high current. If you have set the bias up properly, that current draw is high enough to light the bulb up. The light bulb test only works when then bias is set to a smaller amount.
If the boards were set to their proper bias successfully and ran with no issue for hours, they should be okay.
If you are still worried, you can turn the pots back to the start and check with the lightbulb again.
If the boards were set to their proper bias successfully and ran with no issue for hours, they should be okay.
If you are still worried, you can turn the pots back to the start and check with the lightbulb again.
Maybe I missed something.
Why is the resistance value of R3 and R4 10k ohm instead of 10 ohm as in the original diagram?
Why is the resistance value of R3 and R4 10k ohm instead of 10 ohm as in the original diagram?
Good catch! Those definitely should be 10 ohms.
@Chiptech: I think you need to change R3 and R4 to the proper value. Unfortunately you'll need to reset P1 and P2 to min value before powering up and biasing again.
@Chiptech: I think you need to change R3 and R4 to the proper value. Unfortunately you'll need to reset P1 and P2 to min value before powering up and biasing again.
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Ok. I was hoping that was the issue. Yes both sides were working before I reassembled everything.
I see what I did. I wanted to up the resistors to 2W, but ordered the wrong one.
Thanks to camarillo for sorting this out.
I will replace them, reset P1 & P2 and redo the biasing.
I should be a pro at this when i get done.
I'm back.
Everything is working.
Both channels biased.
Now I have the unit put together and tomorrow I will bias with the lid on.
Close.
Everything is working.
Both channels biased.
Now I have the unit put together and tomorrow I will bias with the lid on.
Close.
It works.
Sounds great after hour two.
No hum, silent.
I want to thank everyone who hung in there with me and ensured I crossed the finish line. I can't say enough about all of the great help and patience.
I'm going back to listening to music.
Sounds great after hour two.
No hum, silent.
I want to thank everyone who hung in there with me and ensured I crossed the finish line. I can't say enough about all of the great help and patience.
I'm going back to listening to music.
That is wonderful news! Very happy to hear your perseverance has paid off.
Enjoy your new amp!
Enjoy your new amp!
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Connecting a REL sub to the F5
One week and going strong. I'm going to check the measurements later today.
I just got a REL sub and see attached for their recommended hook up to an amplifier.
I assume it will work fine with F5, but wanted to get some review on their approach.
I don't want to mess up my baby.
Thanks
One week and going strong. I'm going to check the measurements later today.
I just got a REL sub and see attached for their recommended hook up to an amplifier.
I assume it will work fine with F5, but wanted to get some review on their approach.
I don't want to mess up my baby.
Thanks
