Just in from our friend Steve W. in Canada (who constructs the most amazing vacuum tube amplifiers)…
The best way to describe this next amplifier is itâ€™s a Titan. It has to be the biggest, baddest, heaviest and most powerful amplifier Iâ€™ve made to date! Weighing in at just under 60 lbs. this push-pull-parallel EL-34 / 6L6 is conservatively rated at 110 watts per channel using EL-34 tubes. Capable of driving 4 or 8 ohm speakers via a switch on the back panel, this amp is a tube rollerâ€™s dream.
Simply by plugging in which rectifier tubes you want to use, be it a pair of 5Y3â€™s, 5R4â€™s, 5U4â€™s or even 5AR4â€™s you can match the correct plate voltage with what ever power tubes you choose, be it a set of 6V6â€™s, 6L6â€™s, 5881â€™s Kt-66â€™s, Kt-77â€™s, EL-34â€™s, or even 7591â€™s.
You also have the choice of running the amp in push-pull instead of push-pull-parallel simply by not installing the front four power tubes and switching off one of the two rectifier tubes via a switch located on the right hand side of the chassis. The signal and phase-inverter pre amp tubes used are my favourite large dual triodes 6SN7â€™s.
Now, about the transformers, seeing that this amplifier has to drive thirteen tubes, I thought it only made sense to use a separate filament power transformer. The transformer right next to the larger power transformer is the 20 amp filament transformer. By doing this, Iâ€™ve removed the heater load off of the main power transformer which now only has to supply the high voltages the amp needs.
Along with a hefty octet of 470 mfd 400 volt capacitors bought from West Florida Components, there is more than enough capacitance to keep this amp in the black during those high current moments when the music demands it.
By sharing the load this way, the main power transformer will not be taxed nearly as much. The output transformers are massive Hammonds that can easily handle the wattage this amp delivers.
You will notice a volume control knob located right smack in the middle of the mirror in front of the amp thatâ€™s surrounded in pure copper foil, and that is because this is a fully integrated power amp with a line stage pre amplifier built into it. That means you do not need to buy a separate pre amplifier. You only need to plug in your CD player, satellite, MP3, I-pod, or what ever type of line stage device you like to use, directly into the amplifier.
There are two benefits to an integrated amp, one, you donâ€™t have to go out and spend money on a separate pre amp, and two, you are amplifying completely with tubes throughout the whole amplifying process from pre amp to power amp, and that makes it sound better, way better!
Once again – amazing job, Steve! Thanks for sharing this with our readers.