2. analog
  3. 125078-1452

Bad NOS tubes...

I just want to put this out there...as much as I would not like to...my head says otherwise. Tube buyers beware!!!

On 3/7/16 I bought 6 NOS Mullard 12au7 4003 tubes for my preamp from a vender out of Minesing, Ontario Canada... under the store front name of ’mullard.com’ http://www.mullardtubes.com/Mullard-ECC82-12AU7-CV4003/?ID=0&ProductID=153 and ’ tube products.com’ http://www.tubeaudioproducts.com/Mullard-Brimar/ProductDetail.aspx?CatID=65&ProductID=153#

The owner is one Alfred Kayser. On his site/sites he states all of his tubes are tested and matched for best performance values. Well,I went ahead and ordered and received said tubes. After 2-3 months of use I started to hear unacceptable levels of noise from my speakers,you know, the dirty sound of that dreaded tube noise of a scratching, distorted, dirty volume pot type of noise,which totally infringes upon the music. I went ahead and called Alfred and asked him about it and he just responded there is "nothing he could do" for me. Hey,no problem,but he advertised full-up tested tubes. If it was only one bad tube,I could understand,I’m a realist...things happen.

But!!!

Long story short,I came to find out that four of the six tubes are defective and are not what I paid for. Two are fine. So the moral of this story is...When buying tubes,do not go the cheaper route,find and use a "reputable" tube vender and save yourself some time,money and aggravation. Of course I will never use this guy again for any of my audio needs... Hope this is of some help to the Audiogon membership.

aolmrd1241

Showing 2 responses by dover

dover
2,279 posts
 
lewm
06-18-2016 2:39pm
Jea48, Gold-plated pins are a sure sign of recently manufactured tubes
This statement is completely misleading and not correct. I have many vintage tubes with gold plated pins - from Telefunkin, Mullard, Siemens and many others dating back to the 50’s
lewm
06-19-2016 6:10am
I think any one of us would say that no tube ever made has "gold" pins (as he describes them, carelessly)
No it is not careless, most experienced tube collectors refer to gold plated pins as "gold pins".

lewm
06-19-2016 6:10am
You cannot easily plate steel in the first place. So the notion of gold-plated steel does not make sense, either.
Again this is not correct. My understanding is that to gold plate steel you simply do a nickel plate process first and then flash gold plate over the top of the nickel base.
dover
2,279 posts
 
Further to the above post, it can be useful to tighten (tension) the individual pin sockets in the tube sockets if they have been opened up over time by a bent or oversized valve pin. Better connectivity can reduce noise significantly.

More to discover