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ARC Quality Issues Ref75 Ref5SE Ref10

Over the past two years I had several issues with ARC Ref gear and am wondering if I'm the only one out there having so much "bad luck"?

My issues started when I bought a Ref5SE plus Ref75.
The two meters in the Ref75 had a noticeable different color and had to be replaced by my dealer.

Two of the Ref5SE tube sockets were soldered crooked to the board. I found a loose screw bouncing around inside the chassis when I unpacked it and found that the two crooked tube sockets were not even bolted down to the metal support on the main board. ARC apologized and replaced the brand new Ref5SE.

The replacement Ref5SE blew up after 600 hrs of use. A small component in the power section exploded with a single loud bang with smoke following.

To not end up with a nearly new but repaired preamp I upgraded to Ref10. The Ref10 power section also blew up after two months and only 390 hrs of use. One or more of the smaller white caps in the power section exploded (four or five significant and loud bangs with smoke). My dealer just informed me that ARC is going to replace the failed Ref10 against a brand new one.

I can not believe I am the only one having repeated problems with ARC's new gear!?

Feedback and comments will be greatly appreciated !
decibell
bifwynne
2,206 posts
 
@Jasper ... let me try to translate your "high-English" vernacular into American. As a general matter, ARC says the "slave tube" bias spec should be between 57 and 73 mV assuming the "set" tube bias is set at 65 mV. If you have a tube that is presenting a bias of 5 mV, probably a blown bias resister. I assume your talking about a "slave" tube.

Do I understand your post correctly that you bought a GS-150? If so, I anxiously await your comments ... after break-in.

Meanwhile, I anxiously await for my local ARC service tech to make a house call tomorrow to replace a blown bias resister. Bummer ... no music for 2 days.

@Smoffatt ... very troubling news about Terry Dorn. As an ARC "oldhead," I recall the great customer service from the folks you mentioned in your post, especially Len. Not sure what to say. I am greatly troubled to learn that ARC "may" be shipping shoddy product. I hope your experience is that one in ten thousand case.
tsushima1
1,165 posts
 
@Bifwynne, a close enough 'Interperation'

I am indeed referring to the slave KT120 V11, and associated circuit, controlling bias to that particular socket, the bias resistor of which would appear to have drifted out of spec.
My commiserations on your miss-fortune. As it would seem that this particular fault is not entirely uncommon! I am considering a discussion with the engineer, requesting that he replace the factory bias resistors with one of a higher wattage rating.
Given the timing that our respective Ref150's are under the 'hand' of an ARC certified engineer, there would also appear to be a dilema shared in the 'rumoured' KT150 modification pack,

Unfortunately the GS Is with me only for the duration whilst the Ref is in the shop, however I shall pen a few thoughts, here, for your consideration.
bifwynne
2,206 posts
 
Jasper ... my local ARC just left my house. My Ref 150 sounds great!!! Two bias resisters on the same tube blew. No surprise really. The tubes have almost 2000 hours of use on them and they are ready for a replacement. Maybe KT-150s if this stupid KT-120/KT-150 enigma is "officially" resolved.

Your solution is NOT about using more "robust" bias resisters. The problem has to do with arcing inside the tube itself. Although new tubes can arc, older tubes are more susceptible because of the natural process of heating (expansion) and cooling (contraction) that occurs when the unit is turned on and off.

I am dubious that an authorized ARC repair tech will replace a burned/open bias resister with anything other than original ARC spec. It may seem crude, but one of the functions of a bias resister IS to open if the tube arcs. It protects the amp like a fuse.
tli
52 posts
 
I have three ARC equipment in the last two years.

First, it was the 40th Anniversary, the remote control failed in the first two months. I don't bother to replace it since I always use universal remote for the whole system.

Then, in the first week, Ref 250 failed to turn back on again when shut down, it took a couple of hours of cooling before it could be turned on again. I reported it in this forum. After a length discussion with local dealer and ARC, both amps were replaced after nearly 4 weeks.

Third, recently 40th Anniversary was upgraded to Ref 10. Some of the 6H30 tubes were not working after one month and 200 hours. They were replaced with EH 6H30DR gold pin. They sounded better and are problem free for 500 hours now.

So far, all my experiences with ARC were not perfect. Although I still like their sound, their reliability is a real concern.
no_money
638 posts
 
I didn't think much of it until reading this thread. I've had no issues with either of my ARC pre amps over the years, but, the last set of tubes I bought from them, one 6h30 was DOA. This makes me wonder why I'm paying a premium for these to be tested?
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