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Problem with Ref 5SE

I recently purchased a 5se and took delivery the other day. Did not get a chance to open it up until last night. Upon installing it into system I switched it on and after it warmed up, I was very much interested in hearing how it sounded against my current 27. After listening to several tracks with the 27 I switched pre's and after a couple of minutes playing a CD I got some noise, almost a loud static sound coming from the right channel. It was not effected by changing volume controls or input selector. It went away after 10-15 seconds and then returned. At that point, as it was late, I shut everything down and figured I would take another look in the morning.

This morning I removed the top cover and pulled and reset the output tubes and then the power tubes. I fired it back up and still had the 'static' sound but now it also had a humm, like an impedance type hum and constant. I do not believe that the humm was present last night as it is quite noticeable. 

The static type load noise seemed to have abated after the unit warmed up after maybe 15-30 minutes.

Can I assume that perhaps a tube was damaged during shipping? Do you ARC guys think a new set of tubes will fix this issue or am I looking at something more severe? Any additional suggestions to try and pin this down?

I rerouted the IC going to the amps to get them further away from source IC's and no help...

I am a little bummed, as my initial impression it that it is a leap from the LS27, my current...
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theo's avatar
theo
2,690 posts
 
Not sure what the problem is, but as a Ref5se owner. I did find out that the 6550 power tube needs to be replaced every 2000 hours, this is not mentioned in the manual. It only mentions the 6H30 has a 4000 hour change interval. If you look at the REF6 manual, it now mentions at. My power board burnt, but ARC replaced it as a warranty claim. Just telling you this so you don’t find out the hard way.
That said , have you tried the second set of outputs to the amp to see if that gives the same result? Also the tubes really should have been shipped in the foam packing that ARC includes. If you do ship it back to them ask if they prefer the tubes not in place and maybe they can send you the foam packing cube they sell tubes in.
stevea11757's avatar
stevea11757 OP
130 posts
 
Moved the tube around from the 27 and hum is still present. I guess next is the 6550 power tube, which I will have to order...this is going to ruin my holiday.. :((
stevea11757's avatar
stevea11757 OP
130 posts
 
Okay, after a bunch of reading and research it might just be something that I am going to have to live with. Apparently the S/N is what I am hearing, hum/hiss or whatever there might be no getting around it. I do plan on replacing the power tube and ordering a set of outputs as the unit is a little over 1k on the hours and I plan on using this a lot as I get used to it so might as well have replacement on hand.

Any ARC 5se owners have similar issues? I can't have the only set up that this has become apparent. I am probably used to the LS 27 as I do not recall having any issues with a noticeable noise floor.

Have a Power Plant 20 I have to put into system (my 12 could not handle the Pass and the 27 at the same time, had to do them one at a time, the 5 draws a LOT more.

Should anyone have additional suggestions, it would be appreciated, I was already looking for new balanced cables as I need them a little longer so I can cut the cables for speakers to a minimum. I had another thread I posted earlier looking for IC's recommendations. 
tecknik
483 posts
 
Try a different power cord and if you can plug the pass ( amp Im assuming ) directly into the wall. Could be a ground loop issue.
stevea11757's avatar
stevea11757 OP
130 posts
 
I tried plugging the amps into wall and the pre into my PS Powerplant and then the opposite, amps into PP and pre into wall. The 5se is replacing a LS 27, also a tube unit and I had no issues with that set up.

Ordered a full set of tubes and will be trying that out in a couple of days. While at the moment I do not have any other power cords to swap out as it is a 20a but will look today and see the cost to replace with another power cord. This is turning out to be a costly endeavor...
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