Many folks ask what the difference is between the standard EL84 and the more expensive Sovtek EL84M.
There has been no data available and I see lots of questions on forums etc asking about where you can get a data sheet.
I worked with the Sovtek team and pulled a product information sheet together out of Russian documents etc.
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.
So why even consider the more expensive EL84M from Sovtek?
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. It is also an excellent choice when you want a nice rich sounding amp and you create your tonal range and sound colours using pedals
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 .
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! Fender do the same but the over run margin is less.
The Sovtek EL84M is the military version of the EL84. However, I have read on a number of forums that no one can find a data sheet for the Sovtek EL84M so how do you make a comparison?
The only solution was to get info from the Sovtek engineering team and create a summary product information sheet.
Here is at last some real info to w0rk with . It is not perfect but its a good step forward. I will be adding dimensions to the heat below
The EL84M will run at up to 500 volts HT and also it is designed to withstand the vibrations that are experienced in military systems.
tubes receive a lot of vibration fro the speakers and being lunges from gig to gig in the back of a van. Sovtek EL84M lifetime is estimated to be 5000 hours versus 3000 hours for a standard Sovtek EL84.
The EL84M has much more headroom than standard EL84’s. So coming back to the Vox AC30 example, if you want an an amp that is really clean at louder volumes then the EL84M is the valve for you. “Shadows” or “Ventures” fans will like this sound.
A great choice for Hi-Fi too due to the enhanced clean headroom. It is also a replacement of the harder to find 7189 output valve.
You can buy Sovtek EL84 pairs and quad matched kits from our website. Just check here