Hi forum members. I was looking for some advice on a recent equipment change.
My existing pre-amplifier failed and I set about replacing it on a tight budget. I bought a Cambridge Audio C500 for a very cheap price even though it was sold as "not tested".
So I set it up into my Arcam P85 power amp and listened to some music. Guess what!, everything worked fine, it was in great condition and it sounded superb.
I was congratulating myself on a bargain but when I shut the Pre-amp down there was a small pop from the speakers and my power amp decided to shut down.
It did this a few times but there was no damage to speakers or power amp.
So my question is, is it safe to carry on using this provided I switch off the power amp before the pre amp?
Also does this fault ring a bell with anyone? I have had a look inside and it is pristine. I cannot see any bad caps etc.
Many thanks for your thoughts.
My existing pre-amplifier failed and I set about replacing it on a tight budget. I bought a Cambridge Audio C500 for a very cheap price even though it was sold as "not tested".
So I set it up into my Arcam P85 power amp and listened to some music. Guess what!, everything worked fine, it was in great condition and it sounded superb.
I was congratulating myself on a bargain but when I shut the Pre-amp down there was a small pop from the speakers and my power amp decided to shut down.
It did this a few times but there was no damage to speakers or power amp.
So my question is, is it safe to carry on using this provided I switch off the power amp before the pre amp?
Also does this fault ring a bell with anyone? I have had a look inside and it is pristine. I cannot see any bad caps etc.
Many thanks for your thoughts.
D
Deleted member 550749
I think preamp feeding dc to main amp or cap releasing charged voltage to the amp input , my trick check polarity or ad a vc knob at the middle preamp-Vc-main amp, befor turning off volume down (ground position) then turn off both
Many thanks for replies.
I thought that it might be worth checking the pre-amp output without any sources attached and just looked at the signal outputs from the phono sockets.
When the pre-amp is switched on there is no output at all.
When I switch off, then 100mv DC appears at the phono socket, which decays steadily to zero after about 10 seconds.
Maybe a bad cap somewhere. What do you think?
I thought that it might be worth checking the pre-amp output without any sources attached and just looked at the signal outputs from the phono sockets.
When the pre-amp is switched on there is no output at all.
When I switch off, then 100mv DC appears at the phono socket, which decays steadily to zero after about 10 seconds.
Maybe a bad cap somewhere. What do you think?
it is normal for circuits to have switch on/off transients, and then stabilise.
if you consider it to be faulty, then you need to get the circuit to investigate.
if you consider it to be faulty, then you need to get the circuit to investigate.
the C500 is a poor construction but very simple, automatically change the power supply capacitors (two of poor quality) but not expensive, you will always have a time lag when switching on and off, this is due to the time it takes to establish the rail P and N, turn on the C500 and give it a few seconds before turning on P85.