To Build a Tube Pre-Amplifier

Those who know me, know I've been known to dabble in high-end audio equipment.  It all started when my old man entrusted me with a system he had purchased/built in the 1970s.  He had built the speaker enclosures to pair to a Pioneer receiver and BIC turntable.  While the definition of what is truly 'high-end' can be debated, his system was nothing to blink at when he had his records spinning.  That system has since been adopted by my tchwin, Mark.  In it's stead I bought a smaller system better suited for integration to our TV and Blu-ray player.  I won't go into the details here but it is also a very good sounding system.  I simply enjoy good sounding music.  But the 'tinkerer' in me won't let me just sit idly by and listen.  I have to wonder, 'What makes good audio?'.  So I read about these sorts of things when the mood strikes and when I have the chance to tinker with equipment, I do.

I stumbled upon a company called, 'Bottlehead', that deals all things DIY audio kits.  They have a very well regarded tube pre-amp kit called, 'The Quickie'.  It's $99 of components that, with a solid list of instructions, you are left to assemble/solder.  I decided to jump in and try my hand at building me one of these tube pre-amps.  It all went pretty smoothly and was completely built in about 4 hours.

This is the back of the board where all the hardware mounts and the wiring connections are made.

What good is a project without a beer?  I've been enjoying smoked beers lately.

All wired up.  Resistors, capacitors, potentiometers, tube sockets, etc.

This is the board 'right-side-up' with the tubes (cylindrical glass things on the left and right of the middle knobs) installed.  The board is sitting in a wooden base that I also bought from Bottlehead for $40.

Ashley snapped a picture of me in action with my soldering iron.  Notice the glasses.  Safety first, people!

So what do you do with a 'pre-amp'?  Well most audio receivers have a pre-amp section and a power-amp section to take line-level audio and amplify the signal enough to drive loudspeakers.  My Outlaw RR-2150 receiver is one like this.  But there are jumpers at the rear of the unit that connect the pre-amp section to the power amp section.  When I removed these jumpers I was able to run my CD player (Blu-ray player) through my hand-built pre-amp and then run cables from the pre-amp into the 'Main-In' (i.e. power-amp input) on my Outlaw.  The results were pleasing.

In side-by-side comparison with the pre-amp section in my Outlaw using a CD track of Wilco's 'Impossible Germany' as my reference I was able to see just how good this little 100 dollar pre-amp is.  The truth is, I struggled to differentiate between the two set-ups.  If anything, the tube pre-amp was a little more warm and maybe slightly more 'fuzzy' than the Outlaw.  But 'Impossible Germany' was impossibly delicious every time I listened.

All in all this was a great little 'tinkering' project for me.  I learned a lot and got to practice soldering. All said and done, it was $150 very well spent.

If any of you decide to swing past the house I'll be more than happy to give you a listen.