Electro Harmonix ECC83 12AX7 BALANCED valve/tube for amplifiers
The Electro Harmonix 12AX7 balanced preamp valve, also known as an ECC83 EH, is one of the best preamp valves you can buy. A balanced valve is used in the phase inverter position of the amplifier which is the last valve in the preamp stage. Its purpose is to feed an equal (or balanced) signal to the power valves.
This valve is the choice of professionals.
Electro Harmonix ECC83 EH balanced preamp valve versus the 12AX7
One of the questions we get asked the most is what is the difference between a 12AX7 and ECC83. The truth is there is absolutely no difference.
In the UK and Europe we call this valve an ECC83 whereas in the US and other parts of the world it is called a 12AX7. The EH at the end simply indicates that it is made by Electro Harmonix.
The next obvious question is what is the difference between a standard ECC83 and a balanced ECC83? Well, they all come off the exact same production line so from a manufacturing point of view there is no difference. However, the valve is two valves in one, and very tiny variations in manufacturing mean that some of these valves have internal elements that are identical and some don’t. In a normal preamp position this doesn’t matter but purists say that in the phase inverter position both side should be equal or balanced.
Why choose the Electro Harmonix brand?
This balanced valve has proven to be extremely successful for three reasons:
- Superb tone and performance.
- Low noise and minimal harmonics.
- Long life.
Changing the make of preamp valves you use in your amplifier can make a difference to the tone and feel of the amp. This is also true in the phase inverter position. For guitarists this is very important.
Trying different valves in your amp is called “rolling” your valves and you will hear this term used frequently on the forums.
Just one word of warning when reading other people’s opinions on the forums. The preamp valve is just one part in the signal chain. Every guitarist is using a different guitar, different pickups, a different lead, different strings, different volume and acoustics in the room… I could go on but you get the idea. So don’t be too influenced by other people’s opinions – make your own mind up.
Why everyone should have a spare ECC83 preamp valve
Did you know that the ECCC83 preamp valve is used in every valve guitar amplifier ever made, almost without exception. If you are a gigging guitarist you absolutely must carry a spare preamp valve for emergencies. It can be installed in minutes and save the gig. It’s also a great way of testing what is wrong with your amp when you start to have any problems.