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In Reply to: RE: Grant Fidelity/Psvane tubes posted by jep@online.no on February 24, 2014 at 01:23:55
I just had a somewhat different experience buying a quad of highest grade Psvane 12AT7s. They all tested very strong in output but three out of four of them were highly microphonic. I e-mailed asking if I could return them, and said in the e-mail that I appreciate the lengths they go to in assuring the quality of the tubes they sell and that the many Psvane, Treasure and Shuguang tubes I'd bought from them over the years were all excellent (which is true). I got an immediate polite response, they agreed to send me a new quad (I had to mail the ones I had back to them), and they said they would do an extra round of checking to make sure I got quiet tubes. You might start from scratch with a polite e-mail asking if you can send your tubes back in exchange for new ones (not just get a new set) and mentioning your satisfaction with your 300Bs, and anything you may have bought from them over the years.
The team making the Psvanes has broken away from Shuguang. I wonder if some loss of facilities or other factor has reduced Psvane's quality control and Grant Fidelity is itself being flooded with problem tubes. Even so, they should be able to cull out microphonic tubes - a fingernail tap was enough to test my bad lot.
Follow Ups:
I am not affiliated with Grant Fidelity in any way - I am actually a competitor.But I need to get started on correcting a VERY common misconception...
The fact is ALL tubes are microphonic to some degree. Even tubes that don't produce audible sounds when tapped (more on that in a moment) produce microphonics you can see on test instruments. That is 100% totally normal.
Here is the key point - JUST BECAUSE A TUBE MAKES A NOISE WHEN YOU TAP IT DOES NOT MEAN THE TUBE IS EXCESSIVELY MICROPHONIC!!
All Grant can do is test to see if a tube is excessively microphonic. It's the same for me - I will gladly replace a tube that is excessively microphonic. But because a tube makes a noise when you tap it does not mean it is excessively microphonic.
If I may, I'd like to quote from another one of my competitors, Upscale Audio/Kevin Deal. Here is what he says about microphonics:
"Okay...listen closely class, because I will say this only once: DO NOT TAP ON TUBES! You can permanently damage them! Repeatedly tapping on a tube's glass can cause a perfectly good tube to become too microphonic for use.
ALL tubes are microphonic to a greater or lesser degree. Whether or not that microphonics is audible will depend more on the tube's function in the product, rather than the microphony of the tube itself. In some positions, you will never hear anything, even with the worst tube. In other positions you will hear something even with the best tubes. At that point you make a judgement call: does this level of microphony interfere with my listening enjoyment?
Tubes are supposed to make noise when tap you tap on them! If a tube is truly microphonic, and in a position where it is critical, you will know it. It will feedback as you play music and be so objectionable you'll turn it off."
Allow me to add to Kevin's well written note - if you tap (VERY carefully!!) a tube and you get a sound that stops as soon as the tap is over (immediately or nearly immediately) that is a tube that is NOT excessively microphonic. Excessively microphonic tubes will sustain the noise for a good bit before stopping or will make the noise indefinitely. A few tubes - like the 6922 as an example - will behave somewhat differently and can't be judged the same way, but for most that's an appropriate rule of thumb.
Your fingernail tap test did not indicate excessively microphonic tubes if the only thing you heard was a noise when you tapped. I'm surmising that Grant Fidelity replaced the tubes just because they wanted to take care of their customer by going the extra mile.
If you'd like to learn more about it I recommend an EXCELLENT book the link to which is below. Chapter 3 deals with "Subjective Failures" - or if you want to read more about just microphonics look at page 48.
Too many fine quality tubes are being condemned because of normal microphonics.
Edits: 02/25/14
Jim, it said "Not Found" when I tried to access the link you included.
I hear what you're saying about not banging away on the tubes to "detect" microphonics, and I always tried to use a gentle tap, preferably with a pencil eraser, before getting the George Kaye unit.
I wound up testing a bunch of the 9-pin tubes in my "stash" and was amazed at what the Kaye tester told me. Even a few of the supposedly super-quiet Sovtek 12AX7LPS were not nearly as quiet as advertised.
The link is fixed, sorry!
Seriously, for those of us who don't know triodes from tricycles and whose eyes glaze over at the very mention of anything "technical", your points about microphonic tubes are all well-taken. And agreed with. And not just because I don't know any better.
I keep harping on the Kaye tube checker because it's clearly a "tube tester for dummies" and yet it seems to do things the others don't. My other tester, for instance, an Eico 667, is virtually worthless to me. Except for telling me a tube is dead, which I can pretty much tell by other means.
See if this makes sense to you, from the Kaye tester's operating manual: "The feature that sets this tube checker apart is the ability to listen to noise and microphonics while the tube is functioning in the typical class A circuit. You can perform noise and microphonic evaluation, test the gain of the tube in the circuit and compare and match tubes. Maximum output before clipping is tested."
BTW, I did read, or tried to, all 160-odd pages of the linked tome.
Dave,
You wrote:
See if this makes sense to you, from the Kaye tester's operating manual: "The feature that sets this tube checker apart is the ability to listen to noise and microphonics while the tube is functioning in the typical class A circuit. You can perform noise and microphonic evaluation, test the gain of the tube in the circuit and compare and match tubes. Maximum output before clipping is tested."
Yep, that works for me. That's what the VTV unit does except for testing the clipping point. The Amplitrex can be programmed to do a similar test and much more (as well as listening to a tube). And the Maxi gives a readout of actual noise voltage in db below .775 volts across the audio band as well as letting you listen to the tube. So you and I agree - it's GREAT to have test gear that does something useful!
Now, since you've read the book, see if you can't find posts that give you a chance to apply what you read - or a reason to go back and re-read it. Watch how much you pick up!!
I put Bob Olsen's Psvane 12AT7s on mine and three of the four of them howled like banchees. Didn't need to touch them, just increase the tube checker's volume level a little and listen. Detecting an overly noisy and/or microphonic tube is simple with the Kaye unit. Yes, there are varying degrees of microphonics and it can tell you just how microphonic a tube is.
Dave,
That was not stated in the original post, so I had no way of knowing what else occurred. Maybe Grant Fidelity wasn't being as magnanimous as I thought...
I have 3 devices to check for noise/microphonics - the VTV Vacuum Tube Characterizer, the Maxi-Preamp tester, and the Amplitrex AT-1000. Those devices (and some headphones for the Maxi and Amplitrex) can indeed do a good job of detecting excessive microphonics.
But that was not my point. My point was that often a tube will get condemned because it makes a brief noise when tapped (because ALL TUBES ARE MICROPHONIC to some degree) which is entirely 100% normal.
Also, PLEASE read the Tomer book section I mentioned. Because as I mentioned before in my quote from Kevin Deal, the susceptibility of a tube to displaying excessive microphonics is dependent on
a) the environment in which the tube is operated, and
b) the circuit in which the tube was used
Tomer explains this VERY well, it's a terrific book - and it's free in .pdf form.
Jim, you are correct as usual. There have been recent posts on other forums about tubes, the expensive Holland EL34 copies, and others failing prematurely. They were not purchased from Grant. No endorsement, just a fact. If you buy these tubes, know your seller and be sure the warranty will be honored.
Edits: 02/24/14
My main point was the how widely misunderstood the whole microphonics issue is, and that we get a handle on it. At some point the cost of replacing a lot of perfectly good tubes due to this misunderstanding does impact the purchase price we all have to pay!
Yes it does and a small amount of microphonics make tubes..sound like tubes. I check it with a ball-peen hammer....just kidding. :-)
The team making the Psvanes has broken away from Shuguang. I wonder if some loss of facilities or other factor has reduced Psvane's quality control and Grant Fidelity is itself being flooded with problem tubes. Even so, they should be able to cull out microphonic tubes - a fingernail tap was enough to test my bad lot.
GF allegedly rigorously tests the tube B4 selling them.
Thanks.
I have written two emails of late, but if Grant has died there is no wonder why I haven`t received an answer. Sorry for their loss.
Yes my 300B`s are wonderful so I will contact them again later. It is not the end of the world, 2 x 12 AU7 tubes!
Rgds
JP
I sent a deposit a year ago to Niteshade Audio for an amplifier. The owner was diagnosed with brain cancer and in undergoing chemo. The risk of dealing with the little guy is always there.
A good customer of ours emailed me about this thread, so here is the official answer since the matter has been brought to public forum: I listed the facts here for whoever interested in the matter to make their own judgement.
1) This thread was started by Jan Petter E. from Norway. Grant Fidelity had our first communication with him in Jan 2012 - by Jan asking if we need 'help' to stock tubes in Norway to sell through his business (an importer / dealer of an amp brand). We provided proposal but nothing further discussed.
2) Aug 2012: Jan purchased 2 x 12AU7 Psvane tubes from Grant Fidelity.
3) Sept 2012, Jan said the tubes are noisy in his preamp so he cannot sell them.
4) Sept 7th, 2012: Grant Fidelity provided return instruction to Jan. Jan replied as "So this means that I have to spend xxx money for the shipment back in order to have two cheap tubes (retail price USD 99,- which means that they ARE cheap from the factory) to have them tested? The proper thing would be to send me new tubes" (without returning the reportedly noisy ones.
5) Sept 8th, 2012: Grant Fidelity again explained how warranty works - buyers send back tubes, we provide replacement.
6) Sept 16th, 2012: Jan emailed Grant Fidelity saying 'I sold these tubes to a guy in good faith' but his customer said one tube didn't light up. It appears that the previously noisy tube now has become a dead tube somehow mysteriously.
7) Sept 16th, 2012: Grant Fidelity again reminded Jan that we have given him instruction to return tube for replacement. Jan agreed to return tube this time.
8) Oct 3rd 2012 - Grant Fidelity received Jan's returned tube and replaced it same day. We never questioned why a previous noisy tube now is a dead tube. (It's very rare to have a 12AU7 type of tube to be dead, if it's just noisy in a particular preamp. We screen tubes for noisy with Amplitrex AT1000 which is the most expensive tube tester on the market, with built-in headphone amp. Sometimes high end preamp is more sensitive than the tube tester so a 'quiet tube' from the tester may appear to be noisy in certain preamps.)
9) Oct 19th, 2012 - Grant Fidelity received an angry email from Jan "I received the (replacement) tube today. This all have costed me app USD 80,- in freight and now customs (VAT) !! Why didn`t you set the value low, USD 20;? This all because of a bad tube that couldn`t have been through your “quality control”. I will never recommend anyone to buy tubes from you and I will definetly warn people about you on several Hifi Forum`s we have here. Ridiculous, think of what I at the end paid for these two tubes and you didn`t even excuse about your “quality control”. If it really was a quality control this would never have happened."
10) Oct 19th, 2012 - Grant Fidelity explained that the replacement parcel clearly stated it is 'for warranty' and Jan should provide his return shipping proof of the tube from Norway to Canada to his country's customs to dispute the duty and tax charge. In my email reply to Jan, I clearly stated that we have no interest in further communicating with him should he try to use internet publicity to pressure or blackmail us to do business in his way.
11) Myself, personally added an email filter to stop communication with Jan from Oct 19th, 2012. The reason is very simple - Grant Fidelity does not bend to internet publicity blackmail.
12) Jan placed an order for 300B tubes from our tube website (www.psvanetube.com) in Nov 2013. As order fulfillment from our Hong Kong warehouse is automatic, I wasn't aware of the order is to Jan in Norway, and had no communication with him since Oct 19, 2012.
My comments:
It appears that this 2 x 12AU7 tubes (replaced already over 15 months ago) somehow is what Jan is referring to here as 'Grant Fidelity's lack of customer service'. I had total 29 emails with Jan for his order of 12AU7 from Aug 2012 to Oct 2012 - not sure if that is called customer service.
Grant Fidelity tube warranty policy is clearly posted on our tube website (www.psvanetube.com) for every buyer to read before purchase. We even make it clear that 'if you don't agree with the policy, please do NOT place an order'. I believe in pleasant equal fair business transactions. If someone doesn't agree with the deal, that person should not enter business transaction with us. If you do, I expect each side to hold their position and stand behind their words. Grant Fidelity stand 100% behind our products and our warranty. This is proven by many many happy customers worldwide.
I chose no to communication with Jan since Oct 19, 2012 because it was no longer a pleasant and fair transaction in my opinion. Grant Fidelity is a private business run by real people living a real life. We are not big corporation who has a PR front face n to get rid of bad publicity secretly behind the scene. We run a business for living happy life with pleasant people who share the same value of conducting equal fair transactions in harmony. When people are no longer behave professionally or at least with courtesy, I choose to cut off the communication to cut off the negativity it brought into our life. I deliberately do so especially after Ian's cancer illness - which tells us all that 'life is too short to be miserable, or become miserable because of someone else' behavior'.
Last but not least, Ian is well and very alive. He had spine surgery last November and has been recovering at home. I choose to handle all business matters so that Ian can have all the time and peace he needs to rest and recover, without being bothered by thread like this one. Whoever rumored that Ian has passed away, I politely ask you to remove your thread. It's just plain not nice to spread rumors about someone's life or death, if you don't know what you are talking about. It's bad karma, and very disheartening to me, to Ian, or anyone who cares about Ian to read it. We are all immortals, and we all someday face our own death or people close to us due to disease or some unexpected events. Please be considerate when commenting one someone's health, if you are not expressing your good wishes for them to recover soon.
I appreciate everyone's time to read my reply. I will not further comment on this matter at this forum. I have a business to run, many nice customers to reply emails to, and have Ian to take care of for his recovery.
Thank you for everyone who supported our business and those who will do business with us in the coming future. We always do our best to service our customers, but we always stand up with a backbone.
Happy listening (tubes).
Rachel @ Grant Fidelity
Grant Fidelity - Psvane Tubes
"Last but not least, Ian is well and very alive. He had spine surgery last November and has been recovering at home. I choose to handle all business matters so that Ian can have all the time and peace he needs to rest and recover, without being bothered by thread like this one. Whoever rumored that Ian has passed away, I politely ask you to remove your thread. It's just plain not nice to spread rumors about someone's life or death, if you don't know what you are talking about. It's bad karma, and very disheartening to me, to Ian, or anyone who cares about Ian to read it. We are all immortals, and we all someday face our own death or people close to us due to disease or some unexpected events. Please be considerate when commenting one someone's health, if you are not expressing your good wishes for them to recover soon."
Spot on Rachel, Im happy to hear this and this is worth more than anything in the world!! My greatest wishes for Ian in his recovery.
.
“If you don't like what you're doing, you can always pick up your needle and move to another groove.” Timothy Leary
Rachel, so sorry I repeated what I had read here (on AA) about Ian. My post was removed (thanks, moderators) and I wish the very best to him and you. Still loving those 845T tubes I bought from you guys, btw.
As I said, Rachel has always been very fair and cordial with me.
Aren't transistors alien technology?
I am happy to hear about Ian of course. But one has the right to be sceptical when one experience trouble on two out of two purchases. And I do not appreciate how this was presented here either. And Rachel; You could have sent me an answer. I mean what can a person believe when not hearing anything?
It is also an issue when a return of two smaller tubes will cost app USD 100,-. This is a fact and Grant is of course not to blame for these costs. but one can for this reason hope that the tubes one buys performs as they are supposed to.
This said:
I am very happy with my 300B tubes that I bought and I am thinking about buying twos Psvane 300B spares as well. So not all that bad. I will give the 2 12AU7 tubes another chance in my system and if they perform as I hope I will of course report on that.
Is that what you used?
----------
Tin-eared audiofool, large-scale-Classical music lover, and damned-amateur fotografer.
William Bruce Cameron: "...not everything that can be counted counts, and not everything that counts can be counted."
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