Aware that I might damage the amp by doing so, I connected a 14V, 0.6A linear power supply to my Sonic Impact amplifier and gingerly turned it on. For about 10 minutes it produced very nice sound indeed, and I began to think that maybe it could actually function fine with such high voltage. But then came a distinct "Bang!" and a tiny puff of smoke. I immediately turned the amp off and replaced the 14V P/S with a 9V P/S. Amazingly, when I turned the amp on again, both channels still sounded excellent. I have not yet tried to disassemble the amp to examine the board, but I am very curious to know: what component could I have destroyed through over-voltage without noticeably impairing the amp's functioning?
Interesting. I've heard about people running the amp at 16V for some time without damaging the amp. Also some 12V household wall adapters give varying voltages ranging between 12V and 18 V running the amp have been reported.
I'm running it on a regulated 4/6A DC 13,8 V PSU (giving a rock steady 13,65 to be exact) and it's been playing for about 60 hours now without any problems, sounding very good.
When I first bought the amp, I followed the statements made in the 6moons review about the PSU. In some part of the
interview, one of the readers state that 'Tripath's published maximum voltage for this chip is 13.2V but they told me that a tightly regulated 13.8V supply is okay'.
So the chip, apart from getting a little warmer at higher voltages, seems to be ok.
Maybe the caps don't like the higher voltages or this was a bad one... Hmm... makes me think about my setup .... Hope this is an exception.
Actually, this is the first time I've read about a T-Amp amp smoking it's caps due to high voltage. Does 'linear ' mean regulated? Did you measure the voltage the PSU gives?
I'm running it on a regulated 4/6A DC 13,8 V PSU (giving a rock steady 13,65 to be exact) and it's been playing for about 60 hours now without any problems, sounding very good.
When I first bought the amp, I followed the statements made in the 6moons review about the PSU. In some part of the
interview, one of the readers state that 'Tripath's published maximum voltage for this chip is 13.2V but they told me that a tightly regulated 13.8V supply is okay'.
So the chip, apart from getting a little warmer at higher voltages, seems to be ok.
Maybe the caps don't like the higher voltages or this was a bad one... Hmm... makes me think about my setup .... Hope this is an exception.
Actually, this is the first time I've read about a T-Amp amp smoking it's caps due to high voltage. Does 'linear ' mean regulated? Did you measure the voltage the PSU gives?
you have just to find the capacitors that are hot and replace them with higher voltage ones
running hot reduce the cap life
alain
running hot reduce the cap life
alain
cdwitmer said:Aware that I might damage the amp by doing so, I connected a 14V, 0.6A linear power supply to my Sonic Impact amplifier and gingerly turned it on. For about 10 minutes it produced very nice sound indeed, and I began to think that maybe it could actually function fine with such high voltage. But then came a distinct "Bang!" and a tiny puff of smoke. I immediately turned the amp off and replaced the 14V P/S with a 9V P/S. Amazingly, when I turned the amp on again, both channels still sounded excellent. I have not yet tried to disassemble the amp to examine the board, but I am very curious to know: what component could I have destroyed through over-voltage without noticeably impairing the amp's functioning?
You might want to check the unloaded voltage coming from your supply. Just turn it on and measure what it is.
This is how I ran a 5066 at 16.6 volts for a week. I got around to checking the power supply. It was 18 volts unloaded, and 16.6 volts connected to the 5066. This was a 13.8 volt supply.
The weak link is the stock 330 ufd 16v electrolytic cap on the SI board. The cap most likely can handle 17 - 17.5 volts for a short period of time. But it will live longer if the input voltage is kept down to 14 volts or lower.
The pop was most likely the electrolytic cap exploding. They look like a flower after blowing the can off.
George
I'm with panelhead, I bet your PSU was putting out more than it said on the exterior, and blew the electrolytic cap supply.
Open it up, in the middle of the 4 inductors, should be round black capacitor, dont be suprised to see two little leads and little lead shavings in the bottom.
--BillyM
Open it up, in the middle of the 4 inductors, should be round black capacitor, dont be suprised to see two little leads and little lead shavings in the bottom.
--BillyM
Boy, talk about STUPID !
"Sometimes it really helps to read the fact-filled manual."
It turns out that my 14V linear P/S has TWO DC power output channels, and I had inadvertently connected both of them to my Sonic Impact T-Amp. So instead of 14V I was feeding it with 28VDC ! Little wonder that I blew capacitors on the amplifier. After reconnecting the P/S correctly, the little amp sings amazingly well for a cheap piece of equipment that has been so abused.
So I doubt anyone has anything to worry about feeding their SI T-Amp 14VDC, especially from a high quality supply.
"Sometimes it really helps to read the fact-filled manual."
It turns out that my 14V linear P/S has TWO DC power output channels, and I had inadvertently connected both of them to my Sonic Impact T-Amp. So instead of 14V I was feeding it with 28VDC ! Little wonder that I blew capacitors on the amplifier. After reconnecting the P/S correctly, the little amp sings amazingly well for a cheap piece of equipment that has been so abused.
So I doubt anyone has anything to worry about feeding their SI T-Amp 14VDC, especially from a high quality supply.
Wow, that's an amazing story. At least we now know that the little beasty is more robust than we thought.
Doubt it would live long on 28V, tho...
Doubt it would live long on 28V, tho...
So did you open it up to see what popped? This sounds like a good opportunity to upgrade stuff for a few bucks.
dgo said:Interesting. I've heard about people running the amp at 16V for some time without damaging the amp. Also some 12V household wall adapters give varying voltages ranging between 12V and 18 V running the amp have been reported.
I'm running it on a regulated 4/6A DC 13,8 V PSU (giving a rock steady 13,65 to be exact) and it's been playing for about 60 hours now without any problems, sounding very good.
When I first bought the amp, I followed the statements made in the 6moons review about the PSU. In some part of the
interview, one of the readers state that 'Tripath's published maximum voltage for this chip is 13.2V but they told me that a tightly regulated 13.8V supply is okay'.
So the chip, apart from getting a little warmer at higher voltages, seems to be ok.
Maybe the caps don't like the higher voltages or this was a bad one... Hmm... makes me think about my setup .... Hope this is an exception.
Actually, this is the first time I've read about a T-Amp amp smoking it's caps due to high voltage. Does 'linear ' mean regulated? Did you measure the voltage the PSU gives?
Well, yesterday I blew mine. And I also was using a regulated 13.8V supply (3/5A DC). Did nothing weird. Just turned it on, listened tot some music and suddenly......the sound was gone. And there it was: the smell of something burning. Bad luck or too high a voltage?
This is why I'm going to use at most, a flat 13V on mine and no higher. I can't imagine it's really worth it to take the risk.
Would replacing the caps with higher V ratings allow you to use a larger supply? If so would that increase power and sound quality?
P/S considerations
A few considerations:
If your speakers are sufficiently efficient, staying with a 13.2V P/S is probably a good idea.
I think that if the P/S is of sufficiently high quality (STABLE and NOISE-FREE), one can safely go to 13.8V.
Many power supplies put out voltages higher than what they claim.
I blew the caps in my T-Amp because I doubled up the inputs and was thus applying about 28V to the poor thing. (With proper voltage applied, it still sounds great !)
I think such problems with 13.8V are truly fluke occurrences, and indicate either a (rare) defective T-Amp or a P/S that is not behaving like it is supposed to.
I don't think adding caps can increase the applicable voltage headroom of the T-Amp significantly.
A few considerations:
If your speakers are sufficiently efficient, staying with a 13.2V P/S is probably a good idea.
I think that if the P/S is of sufficiently high quality (STABLE and NOISE-FREE), one can safely go to 13.8V.
Many power supplies put out voltages higher than what they claim.
I blew the caps in my T-Amp because I doubled up the inputs and was thus applying about 28V to the poor thing. (With proper voltage applied, it still sounds great !)
I think such problems with 13.8V are truly fluke occurrences, and indicate either a (rare) defective T-Amp or a P/S that is not behaving like it is supposed to.
I don't think adding caps can increase the applicable voltage headroom of the T-Amp significantly.
All you guys have been plugging in higher vdc adapters into the sonic impact. However, my friend fried his amp when he plugged in a 9V ac transformer into the amp. Is there anything that would be most likely be damaged from doing this?
I've already replaced the 330uF cap that started bulging. All the resistors seem to be fine. When I test the four diodes with my multimeter's continuity/diode test function, I get a short both ways.
Right now, when I turn it on, the led lights up but I get no sound. I'm guessing the tripath chip is dead?
I've already replaced the 330uF cap that started bulging. All the resistors seem to be fine. When I test the four diodes with my multimeter's continuity/diode test function, I get a short both ways.
Right now, when I turn it on, the led lights up but I get no sound. I'm guessing the tripath chip is dead?
9 Volt AC?
My guess is that the AC voltage killed it. The amp runs on 12 -13 volts DC.
George
phugger said:All you guys have been plugging in higher vdc adapters into the sonic impact. However, my friend fried his amp when he plugged in a 9V ac transformer into the amp. Is there anything that would be most likely be damaged from doing this?
I've already replaced the 330uF cap that started bulging. All the resistors seem to be fine. When I test the four diodes with my multimeter's continuity/diode test function, I get a short both ways.
Right now, when I turn it on, the led lights up but I get no sound. I'm guessing the tripath chip is dead?
My guess is that the AC voltage killed it. The amp runs on 12 -13 volts DC.
George
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