I sell vacuum tubes. Buyer that owns an Audio Resarch VT1200 claims I sent him a bad tube

A buyer sent me a message saying that one of the EH 6922 tubes I sold to him was damaged (the driver tube) and that the bias circuit needs repair which will cost $500. The quick research I’ve done is that these amps are unreliable and that this can happen often.

Do you think I should be held responsible or is it the equipment that is not well designed and I shouldn’t be held accountable. Just want to hear your opinions on the matter.

First thing to do is have them return the tube(s), so you can confirm it was yours and test it(them). It’s been my experience that ARC often uses resistors as fuses in their B+ circuits. I suppose, if one were to include shipping and a rapacious repair fee(such as ARC might charge), the costs could be ridiculous. Somehow, there would have to be a short in the plates of a 6922, to damage an amp’s B+ circuitry. If you found a tube that you sold to be defective(in that manner), you’d have to let your conscience be your guide. Did you sell the tubes with any kind of warranty, express or implied? There’s no way to know whether his amp may have damaged by the tubes he had in it previously, other than asking why those were replaced. Then, you’d have to believe/trust the buyer. If you’re referring to the VT200: It’s conceivable that the amp was damaged by the buyer trying to run 6H30s, in one designed for 6922s and they’re trying to bag you(just a thought).
On top of that it would be a good idea to provide links to examples of this sort of failure.
We offer a month return policy, no questions asked. I will ask them to return the tubes to inspect them further.
I would replace the defective tube, but I don't think you have any responsibility for the repair of the amplifier.  If the buyer had sent the amp to your facility and asked that the tubes be installed and the amp tested, then you would have responsibility for the amp.
I have a CJ that blows tubes in the phono section; if I put any kind of tube in it will blow.

Discovering this was expensive, but I don't hold anyone liable, it's an old preamp.  I don't know if this helps anyone because it's just one of those things. 
A faulty design can ruin a tube and blow a fuse .in earlier days some of the less expensive  Chinese integrated amps,power amps are horribly designed. Unless it us a well respected brand like Jolida  they are night and day better then even 5 years ago for example.  If you sell tubes you should give readings for matched tubes under load with each pair. Brent Jesse recordings does, Andy at Vintage tube services for years has Allways inspected under load . With expensive tubes you just cannot afford to just exchange on a $300 pr of rare tubes.
If tubes test as N.O.S  , failure not likely do yo the tube .the amp voltage regulation 
Drifting or weak is very possible as just one possibility .I am referring to  small signal tubes. Power tubes are another animal but still a strong N.O.S pr of power tubes if biased properly should last for at least several 1,000 hours 

What testing do you do before selling tubes?
IMO if you are a viable and reputable business you should reserve some $ from each sale for returns, defective product and yes even the very  rare and ocassional consquencial damage claim.
Not saying you should honor that but IF you lack the ability to adequately test and assure product I would have somebody who can take a look at the subject tube.
Andy as mentioned above by another poster is hyper knowledgeable and has the correct test equipment.
As for the in my view undeserved whack at ARC for " rapish" pricing..that is throwing stones at abreputable company with real engineers and a warranty...shame

You are only responsible for replacing the bad tube with a comparable one. 30 days is a VERY reasonable length of time. I have never heard of a tube dealer who covers the cost of repairs to any tube amps, even if there is proof that a bad tube caused the problem with the amp. Most owners of tube amps are well aware of the nature of vacuum tubes, as well as the fact that tube amps are not the most reliable form of amplifiers on the market. Even extremely well designed tube amps are going to have problems at some point, and spending money to get them repaired is a given.
I totally agree with bigshutterbug on this one!!!!!! Well Said.

Matt M
I will say I've done business with Tonal Tubes and they are great do deal with. I purchased a quad of Gold Lion KT-77's from them last year, one tube in the quad was bad. Tonal just said send the whole quad back and had a replacement quad in the mail to me the next day.  Before even getting the original quad back from me! Stand up guys for sure.
Tomic601: We do test tubes on a Maxipreamp beforehand and will match them as well from triode to triode, tube to tube.

jond: Thanks for the very kind post. We really take customer service seriously and we are glad you were pleased with your purchase!
Since tubes fail and can be damaged in shipment, it seems the amp is a flawed product if a bad tube causes such damage. But I'm no EE.
The buyer’s intentional choice to own tubed equipment and order and install tubes into said tubed equipment, regardless of the source of validated or non-validated quality of such tubes, of ARC or any other manufacturers’ products or components, means that the buyer understood the risks and was willing to take that risk and be knowingly responsible for the outcome, either positive or negative, of self-installing tubes. It could be argued that such tube replacement should have otherwise been performed by a qualified ARC service professional with ARC qualified tubes. The buyer has to accept the outcome of taking such risks when tube rolling. This is not the seller's responsibility, whose liability ends with potential replacement of a defective tube, provided it can be demonstrated quantitatively that the tube was in fact defective before installation. It is possible the ARC component was defective and damaged the tube.
Thank you all for the input. It has really helped us with thinking this one over.
I've read that Upscale Audio will not sell tubes or service Audio Research VT-100/200 amps due to their experience with those amps eating tubes and customers reportingly blaming Upscale.  

brf: That is very helpful to know!
I have also done business with tonaltubes, just purchases some 12ax7 and EL84 tubes, and he is great to do business with. This was my second purchase from tonal. Had an issue with some 12ax7 Gold Loin tubes that my Cary amp just did not like and he refunded me quickly. I sent him back the tubes. His prices are good and service first rate.

Tube amps have issues at times and it is near impossible to blame it on a tube. If tube amp owners always went back to the tube seller when their amps break, then tube sellers would be paying for virtually every tube amp repair! Oh my, nobody would go into the tube business!

No, that repair is not your problem. Even if the tube was bad from mishandling by UPS, USPS, or even the buyer, it should not have caused that costly repair. The amp has design flaws that Tonal cannot be responsible for.
Not to get lost in semantics here, but was the buyer's claim that the tube was damaged?  Or defective?  If it was visibly damaged and he put it in the amp anyway, then he's a moron and got what he deserved.

Regardless, I don't think your responsibility goes beyond replacing the bad tube or refunding the amount paid for it.  I don't know of any tube vendors that pay for repairs to a component, and most clearly state in their conditions of sale that liability is limited to refund or replacement of a defective tube.  Pretty much standard practice in the industry.
grannyring: Thank you as well for your kind comment. We are glad that you were pleased with everything and that the return went smoothly. Glad to hear those EL84s and 12AX7s are going great.

bcowen: He just claimed that one of the driver tubes died after running the amp for 10 hours.
brf said:

I’ve read that Upscale Audio will not sell tubes or service Audio Research VT-100/200 amps due to their experience with those amps eating tubes and customers reportingly blaming Upscale.

While the above is surely anecdotal, I’d hazard a guess that if you polled owners of popular tube amplification, that ARC would be near the "top" of the list in terms of repairs which (while back at the factory) also required the highest replacement rate of "ARC certified" matched output tubes .

I don’t think you can do polls with Audiogon’s forum software, but I’d be interested in verifying if this was the case.

Also, it’s difficult to pin an amplifier failure to a tube, especially after it’s left the seller. One never knows how it was treated (inserted, then removed while hot and subsequently dropped, etc.). IOW, you can’t predict when an internal short will occur in any tube - new, old or NOS.

Edit: the internet noise machine has a way of amplifying negative news, so take the following in that light. With respect to Upscale Audio, they’ve been in business for a long time, and cater to quite the picky audience. That ought to say something about their longevity.  If you think about it, any businessman would love to sell product, and Mr. Deal's refusal to sell to owners of certain products, speaks to his integrity.  Whether he comes off as rude or not (as stated in the thread below) is not my place to say.

With that caveat, here’s a related thread on the topic of re-tubing the VT-100 from this forum (note Kevin Deal’s post from 04-March-2009): https://forum.audiogon.com/discussions/buy-tubes-from-audio-research-or-not


Not sure about all ARC amps but I had a friend install some ’little’ tubes in one and found out even the ’little’ tubes need to be biased. Even the output tubes need to be closely matched within ARC’s tolerance (Master/slave bias). ARC makes some really fine equipment (make no mistake about that) but ARC owners really should go to them for tube replacements.

Tonaltubes learn here to be careful about selling replacement tubes for ARC equipment without knowing their requirements. It’s very possible that the tube you sold was good but not within ARC’s spec’s which took out the circuitry and your tube as a result of that.

Again ARC makes some of the best tube amps but they have some extremely tight tolerances.
I'm not familiar with the amp (is there really an ARC VT1200?), but I've never heard of a driver tube damaging an amp's bias circuitry. Am I mis-informed?
bdp24: I meant to type VT200 in the title but I typed it wrong.
I think Upscale's issues lie only with the ARC VT-100/200 amps.I have retubed my Ref 150 and Ref 40 with Upscale without hesitation from them or complaint from me. 
Another vote for Upscale. They always want to know the equipment you are putting them in. And there certainly do try and keep abreast of the wrong tubes to use for the application & their suggestions have always been excellent for me. For decades.

But they sell an awful lot of tubes. Back to the original question.....that is a very common result with Audio Research. You should have already been aware of that or you certainly know that now. So ask about the application and start keeping track. 

As for right now.....lesson learned and maybe offer to split the repair cost. In the future, say no guarantee with folks doing an Audio Research re-tube.
Please see the Audio Asylum post on Upscale's policy on retuning the Audio Research VT amps


You should have already been aware of that or you certainly know that now. So ask about the application and start keeping track.

It is not tonaltubes responsibility.  He doesn't manufacture tubes - he only sells them.  Pretesting is nice, but after that - who knows what happened.  Things fail (it happened after 10 hours of operation).  It could be bad socket, voltage spike in mains or caused by disconnected speaker, handling of the tube, failure of another component, wrong operating conditions, high ambient temperature (improper ventilation), etc.  Tonaltubes is not in the business of repairing amplifiers.  When you buy faulty brand name part for your car that causes damage to the engine do you go after manufacturer or store that sold it?  Perhaps something should be stated in return policy?
It is a case of cause and effect. There's a reason why Upscale asks specifically what the application is. 
wow great way to make money on tube dealers!

1. get $20 tube
2. send back bad one instead
3. claim $500 or more worth of repairs of the affected equipment.

i've won similar paypal disputes as a seller to a client using this schema shown to paypal representative. 

after all, i always believed that beautiful components such as ARC that come out from huge and classy lab-factory turn to junk very efficiently and quick. all statements here such as 'carefully matched', 'biased' and other fishy requirements only tell me about poor, unadvanced and cheap design. it might've been made on purpose (to charge extra for factory replacement and extra for other repairs due to frequent failures -- the usual cheap trick for extra business) and if not, i guess, ARC dudes should learn some basics from vintage units such as Marantz Model 9, HH Scott 299 how to build reliable tube gear that lasts decades, don't 'eat' tubes and sounds great.

so after all, the reputable ARC isn't that really reputable as it seems, but i'd say quite contrary, but don't worry, it's just a nature of english language to spell different from pronouncing and numbing certain letters...

Kijanki is 100% correct.  What the OP's customer is talking about is called consequential damages and no one covers them.  Not tonaltube's responsibility.  Not 10%, not 50%, not 1%.  Especially after 10 hours use.  Very generous to offer a replacement tube unless tube is DOA and confirmed by testing returned item.  Stick to your guns, dude (or dudette).  IIRC, one of the reasons Upscale does not sell replacement tubes for that series of amps is they require a very laborious and finicky process to retune and re-bias those amps, and tonaltubes has no way of knowing that it was done correctly.  Manufacturer says amps should be re-tubed at factory, owner ignored that at his own risk.  BTW, this from a dedicated tubeophile.  
Wow, retube at factory. How convenient.
swampwalker01-05-2017 10:34pm
... Manufacturer says amps should be re-tubed at factory, owner ignored that at his own risk.
Audio Research makes no such recommendation.

I'm with kijanki as well.  And I would not even mention about no liability if installed in ARC amps.  That implies that if a brand is not mentioned, it's covered.  Like someone else said, it may help to state in the refund policy that liability is limited to refund or replacement of tube(s).  Fight this one all the way, as you don't want to set any precedence.  Good luck!

The first thing you can't do is just plug a tube into a direct coupled amp.....This amp is about impossible to replace tubes in for that reason.  Its not your fault and if he doesn't beleave you tell him to call Audio Research and ask them.....That's why the early VT-100's and VT-200 are not popular.......they are impossible to retube......Its no your problem    autospec
I have a friend that had an ARC amp a few years ago. A tube went out and blew a resister in the process. I replaced the resistor for around a dollar and it was as good as new.
Send the tube back.  Send him a fresh
Tube.   Why piss off a customer for this kind of money.   And all the above response.   Its all because of a tube. 
How much bussness did you lose ???
I've read that Upscale Audio will not sell tubes or service Audio Research VT-100/200 amps due to their experience with those amps eating tubes and customers reportingly blaming Upscale.  
Heresay.  Would you mind providing the link or reference.  It will assure me (and others) that this is not a shill.

please read the entire thread as two independent links have already been posted which validates Upscale's position. 
it's not just about tube, read the whole post of OP.
it's about $500 repair claim that purchaser wants to initiate.
it's clearly about scam and dishonest conduct.
it's also about reliability of 'reputable' ARC gear.

The ARC VT200, like the VT100 mark 1 & 2, can be a bare to bias the 6922 tubes. It is not for a novice that doesn’t know exactly what he is doing.

First each section of the 6922 input and driver tubes must be closely, tightly, matched. If they are not, getting the tube bias set to within the ARC design specs will be next to impossible. One reason the factory sold ARC 6922 tubes for the VT100 and VT200 are so expensive.
The guy with the amp should have bought the 6922 tubes from ARC. In fact he probably should have sent the amp to ARC and had them re-tube the amp.

Not for the novice, or faint of heart.


In no way should the OP be responsible for the damage to the amp.

In my view, the vendor's responsibility ends with testing and shipping the tubes.  Should he choose to warrant the tubes for a short period of time, that's on him as well (tube replacement).

In light of Audio Research's statements, combined with biasing instructions in the owners' manual, the purchaser has taken it on himself to bypass Audio Research as a tube seller.  He can't hold the tube seller responsible for his decisions.

This thread has the potential to derail into related topics - whether an amplifier should require shippig to the manufacturer for a tube change, and I'd rather not go down that rabbit hole, but I suspect you know my opinion on such matters.

Thom @ Galibier Design