analog addict
Glory or Death!
After the usual long hiatus, I'm embarking on the next proof of concept, a parallel single ended 71-A amp featuring a stout power supply with an oil filled cap and two chokes, a voltage regulated plate supply for the dual 6SN7 front end, independent center tapped filament supply for each output channel, and three, count 'em three 71-A output tubes per channel, combining for a mighty 2 to 2.5 WPC.
Why? you ask. Well, first off, because. Secondly, to prove something I've discovered with my last build, a PSE 45 featuring two 45s per channel. IMO, the 3.5 watts generated by the PSE amp has more oomph and bottom end than a similar single 2A3 per channel. Thirdly, because the rumor is that as you go down the old 4 pin triode list, the lower the output of the tube, the sweeter the sound. So far, I believe this is true, so this experiment to see if the trend continues. Anyway, here goes...
A mock up of the layout....
71 A mock up by Analog Addict, on Flickr
The mostly cut chassis, deburred.
71-A build by Analog Addict, on Flickr
The corner welds filed down to provide a seamless surface for painting.
71-A build by Analog Addict, on Flickr
I had to cut the power switch and power light holes myself, which I hate doing, since I can't drill a hole to save my life. Here's what I came up with...
71-A build by Analog Addict, on Flickr
These bulb holders are cool, because as I understand it, they were originally developed for WWII planes, so that the light can be closed off to help avoid detection. Stealth lighting to go with the missile switch.
The painted chassis, inside and outside, featuring a hammered black all in one paint.
71-A build by Analog Addict, on Flickr
71-A build by Analog Addict, on Flickr
And some of the components painted a gloss black...
71-A build by Analog Addict, on Flickr
71-A build by Analog Addict, on Flickr
Next up, populating the chassis....
Why? you ask. Well, first off, because. Secondly, to prove something I've discovered with my last build, a PSE 45 featuring two 45s per channel. IMO, the 3.5 watts generated by the PSE amp has more oomph and bottom end than a similar single 2A3 per channel. Thirdly, because the rumor is that as you go down the old 4 pin triode list, the lower the output of the tube, the sweeter the sound. So far, I believe this is true, so this experiment to see if the trend continues. Anyway, here goes...
A mock up of the layout....
71 A mock up by Analog Addict, on Flickr
The mostly cut chassis, deburred.
71-A build by Analog Addict, on Flickr
The corner welds filed down to provide a seamless surface for painting.
71-A build by Analog Addict, on Flickr
I had to cut the power switch and power light holes myself, which I hate doing, since I can't drill a hole to save my life. Here's what I came up with...
71-A build by Analog Addict, on Flickr
These bulb holders are cool, because as I understand it, they were originally developed for WWII planes, so that the light can be closed off to help avoid detection. Stealth lighting to go with the missile switch.
The painted chassis, inside and outside, featuring a hammered black all in one paint.
71-A build by Analog Addict, on Flickr
71-A build by Analog Addict, on Flickr
And some of the components painted a gloss black...
71-A build by Analog Addict, on Flickr
71-A build by Analog Addict, on Flickr
Next up, populating the chassis....