Frequently Asked Questions

Have you Retubed your amp recently?
If your answer is, "No I haven't retubed my amp since
I bought it years ago and it still works fine," then I think you should read
on. This kind of reasoning is same as not replacing the strings on your
guitar and thinking it still sounds fine as the day you bought it.

My tubes are glowing blue...Are they defective??... NO this is a common question often asked and usually by someone who was misinformed by some tech wanna be. The blue glow indicates NORMAL operation in all power tubes. It is the elctrons being energized across the plates and will glow brighter with the harder or louder you play your guitar or increase the input thru your particular amp. Why should you replace your tubes?
For the same reason you replace your strings, or change
your oil on your car. "To keep it working at peak efficiency and optimum
tonal output."

What happens if I don't replace my tubes?
Replacing the tubes in your amp is like giving your
car its yearly tune-up. On a car you have to change the plugs and change
your oil, if you don't poor performance and even costly problems can result.
This is why you shouldn't try to get 10 years use out of the same tubes.
If you replace your tubes and have the amp properly biased you can retain
that characteristic sound of your amp for quite a long time. Weak tubes
or improperly biased amps can result in a myriad of problems from just plain
horrible tone to a blown transformer. If you let it get that far the repair
bill is quite expensive. Spending a little now can avoid a big repair bill
when it is too late.

Why should you use TNT tubes
The New Tube Co. Has 30 years experience in the tube
industry. We know all the sources and factories that are still in production.
We have the know how to assure a quality control level equal to anyone in
the industry. We sell to Manufacturers and consumers alike and our network
of dealers are knowledgeable and eager to help you with your questions.

Other Tube questions:

Do I need to match preamp tubes?

In a 99% of Audio & Guitar amps do not require this at all.

When should I have my amp rebiased?
Whenever you replace power tubes !

Are there any tube manufacturers in the U.S. still making tubes?
Yes there are but they dont make receiving tubes (the class of tubes
used in audio or guitar amps) mainly broadcast types and industrial
otherwise you have Russia,China, Yugoslavia,and Czechoslavakia making tubes.

Does Fender,Marshall,Peavey, or other High end Audio manufactureres make their own tubes?
No they most definitely do not,they purchase them from the current "Eastern Bloc"
countries or other distributors.

Other Questions:

Do you carry Mullard, or Telefunken
Answer: Both these companies stopped producing tubes over 20 years ago and their is extremely small amounts left available that is usually used or pulled out of some equipment. Do yourself a favor dont ask me about these. We dont look for these anymore and we wont sell them. If you read some article about these and have to have them then get out your checkbook and search EBAY. Mullard However is now being manufactured in the Reflector factory in Russia ( owned by the same company that owns Sovtek.EH,Tunsol, Svetlana, Genalex.These tubes are good representation of modern manufacturing and tube improvements over the original versions.

I heard that the Chinese tubes are poor quality.
Suck huh? Well their 12AX7 is arguably one of the best sounding and performing 12AX7's out there. Used in production by Carvin, Yamaha, ART, Rocktron, Peavey and Fender (at times) Their 6L6GC's are actually very good but not as good as the Svetlana/SED or the JJ/Tesla's Their EL34' arent up to snuff for guitar amps but work well in high end audio.

QUESTION: Hello, I have a question concerning tubes for my Fender Twin Reverb amp. Not sure what year it is but I think it's early 70's. In the back there is a sticker that shows the tube arrangement and which tubes are supposed to be in there. The ones that come out of it, I cannot read. The sticker shows 4 - 6L6GC's and 6 pre-amp tubes in this order:
12AT7, 12AX7A, 7025, 12AT7, 7025, 7025. What I need to know is do I have to replace these with the exact numbered tubes or is there a substitute tube that I can use? And will it have an affect on the sound of the amp? Your help would be greatly appreciated. Thank you!

Answer: The following tubes are interchangeable with 12AX7:
Next we look at 12AT7: 12AT7, ECC81
Next we look at 12AU7: 12AU7, ECC82

6L6GC= 6l6WXT, 5881,7027,KT66

Amplifiers have LETHAL VOLTAGES, avoid accidents and lawsuits have a certified Tech do the work if you are not qualified

PRE AMP Tubes do not require matching in Guitar Amps or Audio amps (99% of the time).
Date Codes: have nothing to do with the matching process
.Matching Tubes: We match tubes the same as most OEM's do by measuring Bias Voltage at Idle Current.

Note: We are tube specialists, we have been selling tubes for over 20 years, we sell to OEM's and consumers alike.
Compare our prices we offer tubes at prices much cheaper than your local electronics store or Music store.
Tube Facts: Tubes are currently being manufactured in Russia, China, Slovakia,and Serbia
US Manufacturing ceased 25 years ago
N.O.S. Means New old stock
JAN Means Joint Army Navy - A Military grade tube, other suffixes are WA,WB, WTC,W. These military grade tubeswere made to withstand shock, vibration, high temps, and humidity for use in military vehicles, ships, planes etc.
Brand Name Tubes: From Amplifier companies are actually sourced from one or more of the overseas companies making tubes, Audio tubes are not made in the US any longer and that is a fact
Broadcast are also available, see our other website page for this info
YUGO/EI tubes: Boutique Amp owners Take Note: Yugo EL84's sound great but draw a high bias current, twice that of the Sovtek EL84's on average. Check with your amp manufacturer if your "Boutique Amp" will behave itself with Yugo tubes or fry them right out. Many Boutique amp manufacturers have not taken this into consideration in their design as a result an otherwise great sounding tube will not bias correctly and fry out. Beware of self biasing amps !!!

Note:The Svetlana name is now owned by the same company that owns the Sovtek name.They owns the rights to the name in the US and Canada and a few other countries. The original factory in St Petersburg is still making tubes and selling them under the Winged C name. In my opinion both tubes are very good quality but different. Tesla: The Tesla tube factory became privatized several years ago and is now known as JJ Electronics or JJ tubes