Unpleasant Noises. Pops, crackles or squeals are three good indicators of valve problems. In fact, this is the first thing as a valve amplifier technician I will look at. There are many other causes of this fault but the first thing I do is to swap out the valves to eliminate those from the equation.

How often should I change the valves in my amp?

“In theory, a valve should have a working lifespan of anywhere between 1,000 and 5,000 hours for common types, and up to 8,000 or so for the more rugged industrial/mil-spec variants.

Do valves wear out?

Basically, all engine valves in almost all cars and model series are built to last the entire life span of the car. Nevertheless, untimely wear can occur due to intensive use or defects and therefore the condition of the valves should be checked at regular intervals.

How do you tell if a tube is going bad?

Crackling, squeals and feedback, excessive noise and muddiness or low output are all evidence of tube problems. Power tubes. The two main symptoms of a power tube problem are a blown fuse or a tube that begins to glow cherry red. Either are typically indicative of a power tube failure.

What is an EL84 valve?

First of all here is some background info as to why this was done The EL84 is a very popular output valve in both Hi-Fi and guitar amps. The standard EL84 is made by JJ Electronic, TungSol, Sovtek and Electro-Harmonix.

What is the difference between JJ EL84 and Sovtek EL84M?

In short, the Sovtek EL84M lasts longer, has a lot more headroom and more watts. It is excellent for folks that play country, and music from the 60’s. If we look at the maximum ratings on a JJ EL84 you can see on the JJ data sheet that the maximum allowable anode voltage is 300 volts .

Are EL84’s over run in amps?

However if we look at a popular amp such as the Vox AC30 which has four EL84’s in the output, the nominal HT voltage is above 300 volts by quite a way. The EL84’s are being over run in these amps!

How much does a EL84 cryo valve cost?

EL84-JJ TESLA CRYO JJ Tesla Cryo The JJ-Tesla EL84 Cryo is the best sounding version of JJ EL84 valve available today.The Cryo treatment enhances the In stock £20.00 Buy Now This valve is the specially treated cryogenic In stock £26.00 Buy Now