2. amps-preamps
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Turning off tube preamp first sends solid state amp into protection?

I have been experimenting with using a vintage Luxman CL40 valve preamp as a separate preamp stage for my L-509X integrated. Because I leave the solid state amp on 24/7, I accidentally turned off the preamp while the 509X was still in Separate mode. The integrated immediately went into protection mode with the power light blinking. I powered it down into standby mode, then brought it back up and it remained in protection mode. It wasn't until I unplugged the 509X and plugged it back in that everything was cool. 

Did I do any potential damage here? What it it happens again? It's pretty easy to accidentally turn off the preamp when I'm leaving the 509X on all the time.
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oddiofyl's avatar
oddiofyl
3,468 posts
 
Preamp passing DC to amp?
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jsqt OP
117 posts
 
I'm not sure, is that supposed to be happening (passing DC to amp)?

I just have my DAC going into the RCA input of the preamp and then the output of the preamp going into the HT bypass (Main In) of the 509X. There shouldn't be any DC current moving between the two should there?
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tonykay
1,298 posts
 
To avoid the "pop" I had become familiar with, I have started to turn on the solid state power amp well before I turn on my tube preamp. Is it the right sequence? Really don't know but I don't get that pop anymore.
wolf_garcia
6,628 posts
 
Always turn the preamp on first and off last, although with many modern systems it might not matter much...but that's been the conventional wisdom for a while. 
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