|
Register | FAQ | Members List | Calendar | Gallery | Today's Posts | Mark Forums Read | Search |
Amplifiers Your DIY amplifier designs |
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
Re: The next phase:
Quote:
Yeah a bit of research seems to throw up that the ECC82 was a bit of a "Do it all" valve, used for frame and timebase oscillators etc and driver stages. The ECC88, I already had figured as it was developed as a VHF RF amplifier, giving better performance than it's predecessors. That they work well as an audio valve is a bonus, however I am given to believe that Microphony can be an issue as with a lot of RF valves as it wasnt so much of an issue in the rf and if stages of a radio/tv set. Some seem to be more prone than others. In a line level preamp I wouldnt expect microphony to be such an issue, its microphone and the first amplification stage in a phono preamp where I imagine the issues would be more apparent. The trouble is, valve types can be a bit "marmite" some love certain types, some don't like em so I say go with what you prefer cos that's the right one. The ECC81 seems to be a case in point, I think its a great valve in a lot of applications but there are a lot who don't rate it. Shame as generally speaking they can be very cheap for good NOS. ECC83.............. I have tried many types and in the end I think you have to go a long way to beat the JJ ones as supplied in the WD kit. I got hacked off with "NOS" mullards after sepnding a bit in the past on them only to find that a lot had a tendency to either fail (heaters) or go noisy/microphonic. I think theres a lot of "NOS" touted about that were reject quality back in the day. Andy. |