Recently, I fixed a Sunfire HRS-8 subwoofer from a friend of mine. I drew the circuit of the audio preamplifier board. To help others with the same problem I am posting here.
thanks for this. my HRS10 just crapped out and I'll see if I can do some fix'n. I did find a swollen cap that may be causing the dreaded humm.
Be careful with the sunfire amps. They run AC power all through the amp and the power supply caps don't discharge like regular amps.
Was able to fix my HRS8 by replacing one cap that I could visually see was swollen (25V 1000uf) - stole one off my parts Oppo83; all up and running. Took a gamble that paid off.
What was the problem you were seeing with the Sunfire HRS-8?
Mine started behaving inconsistently, quite loud, developed a 60Hz hum, and now doesn't operated at all.
Sorry, but I did not have to fix it. I did not draw neither the source nor the power amplifier.
But they are very simple. There is an analog amplifier and two PWM sources that form the down converter. The daughter boards make the audio level sensor that increase the power supply voltage of the amplifier through the PWM amplifiers when needed to increase power.
Good Luck.
But they are very simple. There is an analog amplifier and two PWM sources that form the down converter. The daughter boards make the audio level sensor that increase the power supply voltage of the amplifier through the PWM amplifiers when needed to increase power.
Good Luck.
Thank you for the schematic. My HRS-12 works fine with the line level inputs but I needed to use the speaker level inputs. Using the speaker level inputs the sub went into standby every 60 seconds. I removed the driver and unplugged J6A and all is good now.
While the driver was out I lined the 4 sides with Dynamat and put foam blocks on the back and two sides. The sub is much more tuneful now.
J6A is the 3 pin connector on the right of the pre-amp (top) board.
While the driver was out I lined the 4 sides with Dynamat and put foam blocks on the back and two sides. The sub is much more tuneful now.
J6A is the 3 pin connector on the right of the pre-amp (top) board.
Great subs, but they are complicated to fix for the average man, thats me.
excellent
wow, only on this forum. Well done!
excellent
wow, only on this forum. Well done!
Thursday last week I contacted Sunfire (Corebrands) support and sent this to them:
Hello,
My HRS-12 works perfectly using the line-level inputs. When using the speaker-level inputs it goes into standby every 60 seconds. This happens regardless of the input level or the crossover frequency. The unit is unusable using the speaker-level inputs. Please advise.
Best regards,
Ted Williams"
I got this response this morning from their lead tech (right out of the manual).
Hi Ted,
That would be because speaker level signal is higher volume and the signal coming out of your receiver is Line level so you must use LL only. Speaker level would be used when using much older preamps/receivers that ONLY had speaker level outputs.
I hope this helps you.
Regards,
Hello,
My HRS-12 works perfectly using the line-level inputs. When using the speaker-level inputs it goes into standby every 60 seconds. This happens regardless of the input level or the crossover frequency. The unit is unusable using the speaker-level inputs. Please advise.
Best regards,
Ted Williams"
I got this response this morning from their lead tech (right out of the manual).
Hi Ted,
That would be because speaker level signal is higher volume and the signal coming out of your receiver is Line level so you must use LL only. Speaker level would be used when using much older preamps/receivers that ONLY had speaker level outputs.
I hope this helps you.
Regards,
