Update: DIY All-Tube Phono Preamp Project / Part 1
By Steve Graham
Thunderbirds are GO!
Hopefully International Rescue won’t need to be called. (link)
I was a bit old for it when the Thunderbirds TV series arrived in the mid 1960s, but my two younger brothers enjoyed it. Now I find them charming, in that endearingly hokey way the Brits sometimes do things. They always bring a smile to my face when I watch them. I’m not alone, the series still has many fans. Mind you, I only watch for about five minutes. I’m an Anglophile in my musical and detective fiction tastes, and a semi-fan of British audio equipment. I could never get excited about some of the more expensive gear from the UK, but I am keen on the low to mid priced stuff. My Cambridge CD player and the little Wharfies I love spring to mind.
As with the Thunderbirds, vinyl has a reinvigorated following as well. There is also something charming about the sound of vinyl, especially when used with tube amplification–to my ears at least. (It sounds like music. -Ed.)
At any rate, back to the business at hand. Our DIY all-tube phono preamp project is on! Adrian from Brooklyn, New York is the kind patron of this endeavour. He has faith enough in Wall of Sound, and me, your humble HiFi hack, to the point where he has stumped up the cash so that we may proceed.
Below you’ll find the first downloadable installment in this series. For those who haven’t seen the preambles, I’ll be building an all-tube Tetra phono preamp from the kit sold by John Broskie, the man behind the Tubecad.com web site. I’ll document the process for those interested in building their own. I’ve already built a functioning prototype (see pictures above), but with the one I’m building for Adrian, there won’t be any colouring outside the lines. The stock kits for phono board and power supply will be built using the Tubecad-supplied parts. I’ll even use their two-stage power switch.
As well, I’ll detail the prep of an eBay-sourced chassis. All chassis layout and fabrication, little more than drilling holes actually, can be performed with basic hand tools. There won’t be drawings to follow, just pictures with accompanying text. I’ll also detail the wiring of the power transformers to the power supply board, connecting it to the amp board, and the amp board to the input and output jacks. If this works out well, the next project just might be in the form of a graphic novel (a comic book to you oldsters, like me).
So, if this sounds like something you fancy tackling, open and save the document below for order info detailing the major bits and pieces required to make your own. However, if you do take the plunge and buy the items on the list below, don’t start assembly right away. Wait for further instalments in this series. These will detail the easiest way to get to the finish line, honest. Some of the prices in the list may no longer be precise. The ongoing ?tariff issues” might be one reason.
I’m waiting to see what style of AC inlet the chassis I have on order has. Once it arrives I’ll post the list for the remaining parts.
Fun days ahead!