By Enzo Grazioso
Let’s get one thing out of the way: I love the 2A3 power tube. With appropriately sensitive speakers, I’ve long found that this tube just gets me a bit closer to the music than anything else. I’ve felt this way about every 2A3 amp that ever crossed my path – and fortunately, I’m not alone in this regard. Ask a group of tube amp lovers which is their favourite of all the directly heated triodes,…
Falstaff Hybrid Circlotron Power Amplifier is an excellent design but in truth too heavy and also very expensive so I thought of a lighter version …a kind of small Falstaff…………. R O B I N !!!! I tried to simplify the schema and reduce the number of components but without penalizing the audio quality too much. I found a little magician: the E180F tube ( or russian equivalent 6j9p ). This gold pin, long…
There has been considerable debate over the characteristics of tubes versus transistors….. The goal of this hybrid power amplifier is to take advantage of best performance of both technologies tubes and solid state device. Tube is highly linear without negative feedback, smooth clipping, wider dynamic range, characteristics highly independent of temperature, and so on…but its disadvantages such high-impedance devices that usually need a matching transformer for low impedance speakers. I prefer to…
Three years ago I build the first version of Nocturne – a transformer coupled tube headphones amplifier – equipped with 6C45p triode and then last year a second version with a more performing ( and more gain ) D3a triode strapped, both intended to drive with excellent performance a AKG K550 back closed headphones ( 32 ohms, 114 dB sensitivity ). A few months ago I got to try a planar magnetic open back…
The 6C33C-b is an attractive tube. This indirectly heated, high transconductance, high current capability and low internal resistance, inexpensive triode, from Russia, with a large 60W anode dissipation, originally designed as a voltage regulator for the avionics in Russian military aircraft, it is the ideal “high current” triode for audio applications. The downside? The 6C33C-B requires a relatively high anode current (typically 180-220mA at 180-210V) a high heater current ( 3,6 A with filaments connect…
