LS28 Tube life problems

haygeebaby

New member
Joined
Jun 9, 2018
Messages
16
Happy new year guys.
I've had my LS28 since early 2017. Purchased brand new.
Wonderful unit - sounds great.
However at around 947 hours the stock right side tubes started to crackle. I swapped the tubes out with new items. The left side was fine.
Now running the new tubes - at around 850 hours I notice that the right side tubes start to make crackles again.
Again - left side was fine.
I changed the tubes out again and this time decided to try EH units. Just recently the right side started to crackle again. Around 400 hours into the new tubes.

The unit sounds lovely when new tubes are installed.
The unit is also housed in a hifi rack and is on still points.
The rack is well ventilated.
Above the LS28 is a PH9 - and that unit has been problem free as was purchased at the same time. The tubes in the PH9 give no problems.

Has anyone experienced similar issues with ARC gear?
Any thoughts on what is wrong with my unit that is causing these issues?
 
Had a similar situation on an Audio Horizon preamp.
I monitored all of the voltage parameters on the tubes and noticed a variation in heater voltage.
The unit had a constant current source circuit on the heaters along with a soft start circuit.
I both discussed this issue with the designer and also sent the unit in for servicing but was never corrected.
Just had to live with it.
Sold it but did inform the buyer of the issue.
Has ARC provided any suggestions?
 
another LS28 owner here, almost 2 years old, zero issues, not sure of current hours. I'll have to check....…..

Let us know what ARC has to say
 
Haygeebaby, your situation is intolerable. I do not know what is wrong with your LS 28, but this issue is crying for ARC factory service. Not sure if your unit is under warranty, but regardless, it needs ARC factory service. You say you love the unit. So keep it and get it properly serviced. At a minimum, call Greg at ARC. He can suggest next steps.

Mike, do you know whether the member's LS 28, which was purchased new in 2017 is still under factory warranty.

Bruce
 
Haygeebaby, your situation is intolerable. I do not know what is wrong with your LS 28, but this issue is crying for ARC factory service. Not sure if your unit is under warranty, but regardless, it needs ARC factory service. You say you love the unit. So keep it and get it properly serviced. At a minimum, call Greg at ARC. He can suggest next steps.

Mike, do you know whether the member's LS 28, which was purchased new in 2017 is still under factory warranty.

Bruce

I don’t know. I’m sorry you’re having issues. Hopefully ARC can get it straightened out for you.


Sent from my iPhone using Tapatalk
 
Gents thanks for the responses.
Sorry for the late update. I have an interesting outcome to share.
In the last month I’ve made a bunch of tweaks.
After measuring the room with REW and a mic, I moved my speaker and listening chair position. The hifi rack was also moved as a result. The hifi rack is further from the speakers and also sits over 3 null points in the room.
Surprisingly I have found that the tube noises have disappeared as well.
They where always on the right channel. And when changing to new tubes the sound was fine for a few hundred hours.
Not 100% sure if problem was because the sp20 was too close to the speaker or vibration related.
Also, ARC did respond quickly when I emailed them of my problem.
Happy and surprised with the outcome so far.
 
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