Just recently I replaced the tubes in my amplifier, a Carvin V3 (thats that pretty amp used up there in my banner). Well, what is a tube? To quote www.eurotubes.com:
100 watts of tube goodness...
“They are magical little bottles of joyful tone that allow us to express ourselves in a way that no other device on the planet can…”
Or a more proper definition:
“A valve amplifier or tube amplifier is a type of electronic amplifier that makes use of vacuum tubes to increase the power and/or amplitude of a signal”
Basically, vacuum tubes are used to increase the power of a guitar amp to an audible level. Tubes have been in use for decades in audio equipment, TVs, military applications (radar), and transmitters. Tube amplifiers were largely replaced in the 1960′s and 70′s with solid state amplifiers which use transistors to produce the sound. A solid state amplifier is more reliable (since the transistors don’t degrade over usage as tubes do) and for portability: tube amps are heavy!
Tubes, while seemingly an archaic technology, are still widely used in certain applications such as high power RF transmitters, microwave ovens, and audio amplification equipment: particularly for the electric guitar, recording studios, and high-end home stereos. It’s widely accepted that the tonal characteristics of tubes (also called ‘valves’) are more pleasing to the human ear than transistors.
The problem is that they do not last forever and will need to be changed. There are two reasons someone will change the tubes in their amp:
Don't tell me this doesn't excite you...
- They die:Its not a question on if they will fail, but when they will fail. Tubes, much like batteries have a limited life. We push them into distortion and make them scream their little heads off… they can only take that abuse for so long before they begin to loose the ability to drive your rig. As you can see from the picture at left, these are tubes in action. When properly biased (meaning adjusting the amount of voltage the tubes are drawing while ‘idle’) the amp will get nice and HOT!
2. To completely change the sound of your amplifier:
The type of tube used can DRAMATICALLY impact the sound of your rig! I had a Peavey Triple XXX back when my band began playing out a few years ago. I almost returned the amplifier. It was my first high gain all-tube amplifier (I did own a Fender Hotrod Deville, but thats hardly metal) and it was really just… missing something. So I did a little research on tubes. I come to find out that each different type of tube has different gain structures and harmonic and EQ responses. I thought, “why not? Let’s give this a go…” I ordered a set of KT77s for the power amp and some high gain 12AX7s for the preamp and hoped for the best. Long story short… I dropped these puppies into the amp and fell in love with it. It was a completely different amplifier.
"You think this puny cage can contain us?!"
Guitarists are notorious for “tone chasing”. Well, what is tone? Thats one of those things that we all seem to understand as guitarists but lack the ability to really put in words. If refers to timbre and pitch color and a whole myriad of things that have a direct effect on the sound coming out of your speaker cabinet. It’s a lot like trying to explain to someone how sugar tastes… And don’t use the word “sweet”.
"MOAR TUBES"
Alright. Take a look at this picture on the left. You should notice two distinct type of tubes.
The smaller set of tubes is part of the preamp section of the amplifier. The preamp does the basic tone shaping for your amplifier (its also the part of the amp most responsible for gain or distortion). The larger set of tubes belongs to the poweramp section of the amplifier. This is the power house that drives the whole thing. It basically ‘amps’ up the preamp so it has enough ‘oomph’ (these are technical terms here…) to drive the speakers. BOTH sections of the amp are responsible for your overall tone (equally so), so you will need to replace all of them if you really want to change the sound of your amp.
Ok, so tubes can completely change your sound, right? So how do you know which ones to go for. Well, you can ask an expert. Or use Google. I don’t want to get into too much here, as this article is meant to be more of an introduction on tubes, but I will go over the basic types:
PREAMP – 12AX7
This is a preamp tube (one of the little guys from the picture above). You have different version such as the ECC803 S, ECC83 S (including versions where the pins are made from gold) There are other preamp types, such as the 12AT7 and the 12AU7. It is beyond the scope of this article to go into too much detail, but each tube has different gain structures, EQ response and will react differently to your playing. At the end of the article I will provide some resources you can do your own research with 
POWER AMP – EL34
The EL34 is the tube responsible for that “Marshall crunch”. For guitarists that should require no description! They do make updated types, such as the E34L and the KT77 that tighten up the low end while still maintaning that nice sizzle in the top end without making your ears bleed! If you want that British amp sound, but with a bit more complexity and low end ‘oomph’ try the KT77.
POWERAMP – 6L6
This is the last tube I will cover for this article. These tubes provide BIG low end compared to the EL34 style tubes. They also have much more complex mids and the highs aren’t anywhere near as brittle as an EL34 (but it certainly doesn’t ‘crunch up’ the same… less aggression in this tube).
This barely scratches the surface on what’s available on the market today. I recommend that you do your research on the different types of tubes before making a purchase. They have a HUGE impact on your overall tone and are a rather large piece in the never-ending quest in the pursuit of tone. Oh, and here’s another thing: As long as the tubes draw the same voltage… you can mix and match them for even more tonal possibilities! You will need to get them from a pro, like Eurotubes, to make sure the tubes are MATCHED. If they aren’t, you can end up with a less than stellar performance from them.
So what do I have in that Carvin V3? I have an integrated quad of 6L6′s and E34L’s (Matched of course!) for the power amp and a set of high gain ECC83S’s for the pre amp. I am definitely digging the tone!
They can be expensive, but try and have some fun trying out different types. Happy shredding!
Oh, one last thing. Check out my friends over at Eurotubes. There, you can find comprehensive information about tubes, not to mention these guys have some of THE BEST customer service in the industry and will help you choose the right tubes for your amp and you as a player!
Do you have any videos/clips of the V3 pre and/or post retube? I’m new to your site and I’m sorry if I did not look hard enough but I don’t see any. It would be nice to compare. I’ve owned a V3 since they released but I’ve never really liked the sound for the style I play (death metal/grindcore) as much as I wished when I decided on ordering it; still this amp is awesome for the price. For my tone the amp seems shaky or not as stable or solid with the sound and sometimes fuzzy imo. It doesn’t reach the low end like I want I need a thicker lower sound. I’m running effects now and I’ve got it a lot better which is why I have yet to retube it however I’ve contemplated retubing it for 4 years now. It’s hard for me to go through with it there there does not enough resources online for me to compare the sounds. For the first year+ I remember reading a lot of negative things about retubing and receiving a “helicopter” or “motor boat” sound. In addition a lot of online resources mentioned the original V3′s weren’t assembled to quality so to speak. This makes me nervous about retubing being a 1st Gen V3 owner. I’ve recently began reading a few newer articles like this one and I see a lot more positive feedback from people who have retubed there V3′s but again not enough demonstrations of the results. If you could put up some music/videos I would deeply appreciate it. Thanks.
Hi D,
Let me answer each part of your post in turn:
“Do you have any videos/clips of the V3 pre and/or post retube?”
–Unfortunately I don’t have post-re-tube… but I would be glad to slap some recordings together for you so you can hear what the V3 sounds like with the integrated quad of E34L’s and 6L6′s sound like. I DO have a clip of the amp when I first got it (stock tubes, about 2 months old):
http://www.youtube.com/watch?v=mMnei98yHHc
My tone is the one thats much more obvious in the mix. Give me a day or two and I’ll get a video up of the amp as it is now.
“I’ve owned a V3 since they released but I’ve never really liked the sound for the style I play (death metal/grindcore) as much as I wished when I decided on ordering it; still this amp is awesome for the price.”
–This is a fantastic amp and can certainly do what you are asking it to. The answer is in fact, getting the right set of tubes.
“For my tone the amp seems shaky or not as stable or solid with the sound and sometimes fuzzy imo. It doesn’t reach the low end like I want I need a thicker lower sound. I’m running effects now and I’ve got it a lot better which is why I have yet to retube it however I’ve contemplated retubing it for 4 years now. “
–After 4 years there is a very good chance your tubes are just on their way out, hence the fuzzy sound and lack of low end definition. Tubes don’t last forever and need to be replaced every so often. The more you use them, the quicker they will die out. This is exactly what my V3 started to do.
“For the first year+ I remember reading a lot of negative things about retubing and receiving a “helicopter” or “motor boat” sound. In addition a lot of online resources mentioned the original V3′s weren’t assembled to quality so to speak. This makes me nervous about retubing being a 1st Gen V3 owner.”
–I am also a 1st Gen V3 owner. The ‘motor boat’ sound tends to happen in CERTAIN V3′s when run up to bias (meaning the tubes are being driven hard enough to sound their best) in EL34 type tubes only. This includes the KT77. Unfortunately, the only way to find out is to re-tube it and see what happens. MY amp does this. It’s annoying, as I wanted to run KT77′s and they just don’t have the same punch when biased too cold. When run in an integrated quad, the amp won’t motorboat, even with EL34′s. Once again, this doesn’t happen with 6L6 type tubes. I don’t really know why it does this. The newer generations seem to address the problem, but I have yet to try one. This problem aside, I assure you they are very solid amps.
You can get that low end you are looking for with KT77′s… they would be perfect but you run the risk of getting the ‘motor boat’ sound. You can go with an integrated quad, which is what I did. Using a matched set E34L’s will get you the aggression and sizzle needed for a good high gain amp and will be complimented by the deeper low end of the 6L6′s (which will also smooth out the shriller high end EL34 types tend to have)
“I’ve recently began reading a few newer articles like this one and I see a lot more positive feedback from people who have retubed there V3′s but again not enough demonstrations of the results. If you could put up some music/videos I would deeply appreciate it. Thanks.”
–As I write this, it’s 1:00am Sunday morning. I will have a video for you sometime later today
Check out http://www.eurotubes.com in the meantime. TONS of info there!
Hi D,
I feel like a jerk for not getting the opportunity to post the video. However, I have practice with my band, Thy Kingdom Gone (www.thykingdomgone.com) on the 4th. I will record the practice and post a clip for you!