Knghifi ... that's a lot of scratch for tubes ... be it Upscale or ARC. Ironically, Upscale charges about $50+ for a KT-120.
If I have a "next time," I might check out a Pass or Ayre solid state rig. Both have earned high grades. In the meantime, I'm all ARC. |
Thanks Knghifi ... but my wallet is closed for now. I don't have the time, patience or interest to do an audio re-do. What I AM thinking about is signing up for Tidal and stream hi-quality digital in my DEQX PreMATE. Getting too lazy for the CDP and TT. Just want to relax in my cave and listen to my favorite tunes from the past. I like rock and roll music from the 50s, 60s and 70s that comes with harmony, a snappy beat and yes ... words. |
I can speak about the Ref 150 SE as compared to the "old" Ref 150. I upgraded my Ref 150 in March.
IMO, I think the SE upgrade effected an across the board improvement. I'd say half came from the KT-150 tubes and the other half came from the circuit changes. Bass is better defined. Better imaging and soundstage. Mids and treble sweeter and more open.
ARC charged me $5K for the upgrade. Pricey ... but I suppose it was worth it.
Hkaye ... take a look at Oregonpapa's posts about his Ref 75 SE. He's in 7th heaven. |
Bdp24 ... you wrote "why so many ARC? Brooks' tech Tom told me he was constantly repairing ARC power amps because when a tube blows in one of them it often takes with it some of the circuit board parts. The tubes aren't fused---ARC uses resistors and capacitors in that role!"
Nonsense!! I have owned 3 and half ARC amps over the last "n" years: VS-110, VS-115, Ref 150 and currently, the Ref 150 SE.
Have tubes arced and taken out bias resisters?? Yes!! But how often?? Maybe once or twice a year. And since I've been using KT-120 and KT-150 power tubes, tube arcing has been a very rare occurrence.
Cost of repair is about $100. There's an ARC authorized tech who lives near me and who makes house calls.
Have other A'gon members reported very serious problems with the ARC amps? Yes, on rare occasion. But I don't recall the last reported occurrence.
Look ... if you want tubes, this is the cost of admission. Oh ... some might say other tube amp manufacturers use circuit breakers to protect the amp if there's a tube arc. True.
But ARC told me they prefer not to use circuit breakers because they believe it's an artifact they would prefer not to add to the circuit. Is that credible?? Haven't a clue. And frankly I don't care.
Cheers,
Bruce |
Brf ... tubes arc. It's what they do. The problem isn't with the amp ... it's about the nature of tubes. The only fair push back point is that ARC doesn't use circuit breakers. I can't answer that question because I'm not an electrical engineer. All I can do is pass along what ARC told me. Take it FWIW. |
Bdp24 ... I respectfully disagree with your views about modern ARC amps. I think your car analogy is ridiculous and simply not fair.
As to the mysterious Mr. Tom's comment, I don't recall ever seeing burn marks on the circuit boards of any of my ARC amps. Nor do I understand Mr. Tom's comment that mounting power tubes on the circuit board is a bad idea. Where else should they be mounted? Btw, is Mr. Tom an electrical engineer. Does he design and manufacture Class A electronics??
Just an fyi, ARC has been in business for over 40 years. That stands for something to me.
Your mid-1980s Bill Johnson story is not relevant. ARC gear has come a long way since 1985. And your anecdotal comments about the SP-3 are similarly not relevant nor persuasive. The SP-3 was first introduced in 1972 and was later modified several times in the 1970s.
Nowhere do you mention that you actually listened to modern ARC gear. So I'll ask you now. Have you ever seriously auditioned a current ARC Reference amp such as the Ref 75 or Ref 150, or the Ref 5 SE linestage?
Finally, I will conclude by saying that at some point, our hobby comes down to very subjective tastes. If you seriously listened to modern ARC gear and walked away underwhelmed, I would respect your opinion. However, bashing ARC for its design choices concerning bias resisters is just a bit over the top for me.
Cheers,
BIF |
Lostbears ... I may have overstated the arcing frequency. It really doesn't occur all that often.
Yeah ... I'll check the tube bias about once a month, especially with new tubes for the reason you said. Sometimes if I'm bugged about something, I'll check the bias just to take my mind off other stuff.
As far as tube replacement goes, I follow ARC's recommended guidelines. In the case of 6550s and KT-120s, ARC said 2000 hours. Maybe I'll went out to 2200 hours, but I started to get nervous that a tube might arc.
Kal told me that the KT-150s should run longer, maybe 3000+ hours. I need to recheck KT-150 tube life again with Kal. Frankly, I forgot.
Oh ... one practical point about biasing tubes, which I'm sure you already know. Tube bias readings can vary based on AC line voltage, which in turn can vary by region of the country and the time of day.
So after all these years of owning tube gear, I don't obsess about bias adjustments. I try to get the set tube adjusted to 65 mV, but I'll take 64+ mV as long as the slave tube is within spec (57 to 73 mV). If the amp sounds differently because of small bias voltage differences, I can't detect it.
Last point about repairs. I would be very circumspect about sending any of my gear back to ARC unless there was a compelling reason, e.g., a massive component failure or an important factory upgrade such as the SE upgrade. For small stuff like burned bias resisters, I call an ARC authorized service tech who makes house calls. The gear is simply too heavy to schlepp around.
If and when my tech retires, I would not be overly troubled to call another qualified tech who knows how to use a soldering iron. Bias resisters are not a high tech fix.
Other stuff, dunno. I'd call Kal and ask his advice. After reading about UPS and FedEx shipping horror stories, I'd really prefer to avoid the hassles.
Best,
BIF |
Don c55 ... No question about it ... Pass Labs gear has a great reputation. And I am glad that you are enjoying your Pass Labs amp.
But let's put your comments into a little perspective. The D125 was introduced in 1988 and discontinued in 1991. My goodness, it's been almost 25 years since the amp was discontinued!! There's been a lot of water under the bridge since the D125 was on the scene.
As I already mentioned, I've owned 3 and a half ARC amps in the last 10 years or so: VS-110, VS-115; Ref 150; and Ref 150 with SE factory upgrade. NEVER had a flame out. Burned bias resisters ... yes. Massive circuit failures ... never.
Btw, I also own other ARC gear: Ref 5 SE (linestage); CD-8 (CD player);and PH-8 (phono pre). Never had a burned tube problem, flame out or any other problem for that matter.
I think most of the crabbing in this thread goes to the inherent nature of tubes ... they arc from time to time. No getting around that. Of course, the other point is that ARC does not use bias circuit breakers. If it did, it would be a simple matter to push a button and you're back in business. Voila.
I surmise that cost cutting is not the issue here. Jeez, the Ref 150 SE lists for $14K. How much could little circuit breakers cost?? Either Kal or Len of ARC told me many years ago that the reason ARC use bias resisters was to minimize artifacts in the signal path. I'm not a EE, so I can't speak to the pros or cons of that choice.
Heck, if I knew my way around solder and a soldering iron, I'd replace the darn resisters myself. Just afraid of messing up my amp.
As I posted above, if after auditioning amps, one chooses another brand because it sounds better, then what can I say?? Or, if having to replace tubes or, on the rare occasional, having to hire a tech to fix a burned bias resister is too much hassle, then an ARC tube amp is not the amp of choice. Personally, I'm ok with ARC amps and other tube gear. |
Don ... as I said in my posts, I've gone through a lot of ARC gear (linestages/pre; amps; CDPs; phone pre's) over the last 10+ years ...always moving up the line. From a consumer's perspective, I think I'm on solid ground about what I post because I have been there and done it with a lot of ARC gear.
Don, you may also notice that I do not shoot off my mouth about stuff that I have no hands on experience. I don't recall ever pissing on gear that I have never owned or auditioned.
If I catch an ARC thread and have something to add, I do. Likewise, if I catch an ARC thread that makes unfair, irrelevant, nonsensical, and exaggerated comments, I will also speak up ... just like I did here. IMO, ARC gear is worth auditioning. Underserved pejorative comments damage the reputation of a good company.
Sorry if I irritated you. And btw, Stan (Stringreen) knows a lot about VPI products. Folks in the market for a TT who are thinking about VPI would do well to read Stan's posts.
Have a great day.
BIF |
Knghifi ... not really. The last couple of re-tubes came from ARC because the bias spread on power tubes sourced from a reputable tube vendor drifted too much. Btw, I may have overstated the times tube arcing has taken out bias resisters. I was being conservative and may have overstated the issue.
The main point is that power tubes may arc on occasion. The result cold be a blown bias resister. Also, at least with ARC amps, bias needs to be manually checked and adjusted on a periodic basis. This type of care and feeding may make ARC tube amps a non-starter for some. And that is a rational reason to consider another tube amp brand or a solid state amp.
In my case, it's not a big deal. I like the other pluses that ARC brings to the table.
Just saying. |
