Let's Get Small: Low-Power Vintage Amps

How’s everyone doing? This month we’ll take another little trip down memory lane. You may have noticed how often I’ve mentioned tiny, 5-watt (or less) practice amplifiers for recording. One of my recent favorites has been the Fender Champion 600. You might remember a few issues back, when I was recording late into the wee hours of the morning? I stumbled across a particular signal chain that sounded just stellar at pin-drop volume: my guitar plugged into a BJFE Baby Blue Overdrive pedal and connected directly to the input of the Champion 600. From there, I used a really cool-sounding combination of a small diaphragm condenser microphone (Neumann KM 184), connected to my Great River ME-1NV mic preamp right before it hit my Pro Tools Digi 002 Rack.

Kalamazoo Model One

So far, this combination has been great. However, on a recent trip out to California, I rounded up a few dusty old relics of mine that had been in storage for many years at a friend’s recording studio. They had been patiently waiting up in the rafters for me to pack up and ship home. There were three little student-model combos in total: an early-sixties Kalamazoo Model One, a really cute Kay Model 703 from the mid-sixties, and a Gibson Skylark GA-5T from the late sixties.

The Kalamazoo Model One has one RCA 6BQ5 (aka EL84) output tube, along with a single RCA 12AX7A preamp tube, and sports an old-fashioned RCA 6X4 tube rectifier. The single, class-A EL84 puts out roughly 5 to 7 watts RMS, and gives you a nice, warm tone at lower to medium volumes.

Inside the Kay Model 703, the layout is similar to the Kalamazoo. However, it has some odd tube choices when compared to today’s modern practice amps: a 35Z5 rectifier tube; a 50L6 model output tube that puts out a healthy 3.8 watts (using cathode-bias at 200V, according to the RCA Receiving Tube Manual); and a 12AU6 pentode preamp tube positioned in the corner of the amplifier’s chassis.

Kay Model 703

The Kay 703 features a very small speaker (no more than 6 to 8 inches in diameter). Is this something that might’ve been used for a Hawaiian lapsteel guitar? It definitely has that vibe to it. Regardless of its intended original application, there’s a rock ‘n’ roll giant lurking inside. And, as if that weren’t enough, there are three instrument inputs on this amp, too!

The Gibson Skylark GA-5T uses a 6EU7 preamp tube. A pair of EL84s power the combo, giving it about 12 to 15 watts of power. There is also a 6C4 tube found inside this combo. One of the coolest things about the Skylark GA-5T is the tremolo circuit, which is very, very deep and rich sounding. This feature alone could make the amp highly useful for recording cool sound effects.

Gibson Skylark GA-5T

After I pulled them down, I fired them up and had a listen. I had brought a couple of very familiar overdrive pedals with me to California, since I was quite curious to hear how these little monsters would sound when I pushed them a bit harder. Previously (some eleven years ago), I had only used the Kalamazoo’s Volume control to dial in the amp’s output level—with just a quick tweak of the Tone control to adjust its approximate tonal character. But since then, I have discovered that with the judicious use of any number of great overdrive/distortion/fuzz pedals, amps like this could yield some very big sounds indeed. And all three of these student practice amps happen to have Alnico magnet speakers in them, too!

With the amps all sitting in the main recording room of the studio, the first pedal to hit the Kalamazoo’s main input jack was a Crowther Audio Hotcake. This was more than great, as the sound I heard emanating from the 10” off-brand speaker was akin to a lovely sounding roar! It was stunning, to be quite honest. Single-coil guitars sound absolutely righteous through the Kalamazoo Model One. Apparently, it can be any style of single coil, too, whether they’re “small aperture” single coil pickups (like your typical narrower Fender pickups) or any larger single coils, such as the old-style DeArmond Dynasonics used back in the mid-fifties.

It’s important here to note that you should experiment with the various instruments in your own collection, as you’ll likely find that some will bond instantly with one particular amplifier, while other guitars will have you sitting on the fence. Believe me, you’ll know immediately which guitar works when you plug it in. There have been some really magical moments for me since I’ve gotten these little tone machines back.

Just in case you’re wondering, I paid $5 for the Skylark and $25 for the Kalamazoo Model One. The Kay 703 came with a guitar—I paid a grand total of $20 for both of them. The moral of this story: keep your eyes peeled for neighborhood garage sales. Tonal treasures are living right under your nose. Have fun; we’ll see you next month.

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Dean Farley
Dean is the chief designer of "Snake Oil Brand Strings" (sobstrings.net) and has had a profound influence on the trends in the strings of today.