Portrait of a tube
Author: Jac van de Walle
Why use E182CC?
Perhaps you had the feeling before. Like remembering when some specific tubes were easily available, and cheap, and nobody wanted them, and you thought this was the right attitude. However you were not observing an attitude, but market rules of supply and demand. Now interestingly, supply can go up, when old stocks are discovered and sold, but while I write this page in 2015, I do not think this is going to happen any more. I think most NOS supplies have now been discovered. People are either sitting on it, or selling it. So supplies be less, and demand can go up. Such a situation can cause a sharp rise of the price, when demand was very low. The only thing that needs to happen, demand gets average, and then we will immediately see how good ar bad the supply situation will be. The curious thing is, almost nobody sees a reason so buy tubes, put them away for later, when the prices are still low. Yet, such tubes with a relatively low price, that's a tube with the best potential, provided it is a potential Audio tube. think E182CC has that profile. It was never made in huge quantities for many decades. This tube for computer applications was rather made for a short period only. Supply is there, since just one computer used a great quantity of them. If those reach the end of (computer) lifetime, that means you needed to replace all tubes in the whole computer, and actually most would be fine still. Of course nobody seriously would test a few hundred tubes, and try to put back the good tubes into the computer to save money. If one of t hose would fail, the whole computer would perhaps fail, and you had to re-tube everything again. So in regularly intervals they used to exchange all tubes, no matter if they were still good. That explains to me the good supply of used tubes, which are still above 85% or so.
What is a computer tube? Well it is nothing but a tube that can switch a low impedance load fast. As circuits are digital anyway, high gain is not so incredible important. More interesting is low output impedance is speed. As Triodes have a low output impedance, a typical driver tube like 6SN7 would be a candidate, but it's saturation voltage is not so low as with E182CC.
So what makes a nice computer switching tube:
The above can nicely be achieved with a double triode. Now comes the question, can this be used for audio? The answer is a firm Yes, but! The "but" is simply a tube like this is not suited for low microphonics, low noise, low hum, and low anything applications. BUT.... it is an wonderful l driver tube, or small signal output tube. In such applications the E182CC works nicely without hum and noise. Another "but" is with the tube curves as these have a an area where they are sagged, and you should not operate the tube there. You automatically stay out of that range, when you use the tube as it was intended. That is: At high plate dissipation, at high current, and not at too high voltage. If you do that, it becomes a wonderful tube, and the audio community has just started to discover this!
Applications are when you need a strong and low impedance signal of not so high AC Voltage:
... I've found, in general, that the E182CC (7119) and 7044 measure better than the ECC99 in a similar circuit. But all three are very similar, and very good, line amp or driver tubes. (Pete Millett)
... I use a E182CC as a input tube for my SE EL34 amp and absolutely love the sound. I have tried 5687s and 7044s but prefer by far the E182CC/7119. Try one and see what you think. If we only used tubes that were "recommended" for audio we would be ignoring some great sounding tubes. (GAVIN on http://www.diyaudio.com)
... I used the Mullard E182CC and suggest only tubes by Mullard, JAN-Philips or Siemens in the output. (Andrea Cuffioli)
Bothers and sisters:
ECC99 -12BH7 -5687 - 6N6P