Hello everyone I am getting distortion(clipping) when running 4 ohm speakers on the WOPL400. It's happening when I play it loud or increase the bass. I ran it with 8 0hm and played it loud had no distortion but it did stop playing and I had to reset the power. Okay before anybody says I should be running 8 ohm let me say that the PL400 has been running 4 ohm for 50 years without a problem. I have blown a fuse(8 AGX) maybe like twice when driving it extremely Loud back in the 90s when I acquired the system. My speakers setup is 2 Pairs of Bose901 series1 connected parallel. PL400 has been a true workhorse Im hoping that this problem is just a simple fix.
WOPL running 4 Ohm speakers
- Thread starter plex
- Start date
I wanna say around 100 maybe bonucing around the red. Now the left meter looks like it's stuck at 30. The right meter has not worked for a very long time, it was dropped on the right side one day when the amp was moved. How come running a stock PL400 at 4 ohm produced no clipping?
WOPL Sniffer
Veteran and General Yakker
are you using a fan on the back?
No. Should I? I never have.
WOPL Sniffer
Veteran and General Yakker
WOPL Sniffer
Veteran and General Yakker
If your thermal switch set, thats a good indicator you need a fan.
WOPL Sniffer
Veteran and General Yakker
4 fin or 8???
WOPL Sniffer
Veteran and General Yakker
who WOPL'd it?
4 fin
WOPL Sniffer
Veteran and General Yakker
So you have about half the cooling area as an 8 fin. We ALWAYS recommend NOT doing a 4 fin................................
My son and I. Newbies not pros.
WOPL Sniffer
Veteran and General Yakker
Get an 8 fin to do.
I understand about the cooling 4 fin vs 8 fin. But clipping is happening right away.
WOPL Sniffer
Veteran and General Yakker
With the added performance a WOPL brings out, it also brings out a lot of heat. 4 fins is riding the fence on cooling. Put a fan to it
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WOPL Sniffer
Veteran and General Yakker
You may have something wired wrong or maybe your bias is incorrect. What did you NOT replace when you WOPL'd it??? Are all the outputs new? New back planes? New control board? Maybe post some pics... Something is wrong with your build. Joes directions say the builds are VERY ADVANCED and many beginners have had problems. 1 cold solder joint could do it. If you had a tech build it, you would have recourse.
WOPL Sniffer
Veteran and General Yakker
did you try a different preamp? Your pre may be doing it.