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AR Sp8 possible breakdown

.Hello everyone, I just bought a SP 8 mk2 and I am not familiar with the startup processes of this device.
The problem is that when it turns on after the 2 minutes of security, the left channel hits a bang and sometimes it takes a few seconds after the other channel to play.
If I turn it on with the mute function on ok and wait a little more than two minutes, I don’t know about this problem.
Should I be concerned?
tenoris
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cleeds
5,949 posts
 
The SP-8, like most ARC preamplifiers, should automatically go into mute when it is powered up. After the brief warmup, you should here the relay softly click, and then it will unmute. It sounds like your unit has an issue.
mijostyn's avatar
mijostyn
8,570 posts
 
Cleeds is correct. All ARC units are in mute until the tubes warm up. When the unit wakes up there should not be any "bang" and both channels should wake up together. You need to contact ARC and find out where your local repair shop is. 
atmasphere's avatar
atmasphere
11,803 posts
 
With a preamp or any electronics this old, the first thing to attend to is getting the filter capacitors in the power supplies replaced. This should be done before looking at any other problems, as old filter capacitors can easily damage the power transformer, which is the most expensive part in the preamp other than the chassis, and certainly rare.
Get that done first! Then see if the preamp even has a problem after that.
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