Priced at $1,699, the 6L6-powered T50C combo sports a host of features and a great vintage sound. Equipped with a Celestion G12-75, 12-inch speaker, the amp is beefy, weighing in at 75 pounds - even heavier than a 2 x 12" Fender Twin Reverb reissue. A big part of the reason for the weight is the massive power transformer, which also contributes to the sound.
The amp is equipped with two channels: clean and overdrive with separate bass, middle and treble controls for each. The overdrive channel has gain and volume, while the clean channel operates via a single volume control. A master reverb and presence functions on both channels. The power switch/standby set up is a little unusual; the standby is on the front, but the power switch is on the back.
On the back panel, the T50C sports several features that increase the amp's utility. One feature that I really like is the low-power switch that reduces the output power to 12 watts. This feature allows you to get the high-gain saturation sound at lower volume (and save your ears).
A handy effects loop with separate Channel 1 and Channel 2 sends/returns allows use with pedals and rack effects. The main amp- out and the external amp-in jacks allow the amp to be used in "daisy chaining" with other amps.
The tube complement includes two Svetlana Russian 6L6GC output tubes, and six 12AX7s and a 12AT7 in the preamp section. For those of technical proficiency, the amp contains a built-in, tube bias/balance adjustment circuit. With just a simple volt meter, you can adjust the balance of new power tubes - if they are not matched - and adjust the bias once they are matched. The tube circuit also contains an output "trouble" LED that glows red if a tube fails. All in all, the tube biasing/balance section is a nice touch.
If you want more speaker volume, an external speaker jack is available for separate speaker cabinets - with an adjustable impedance switch for precise matching to 4, 8 or 16 ohm speaker loads.
Inside, the internal components are laid out on PC boards. I do not believe that PC board- mounted guitar amps are inferior to hand-wired amps. Like other quality PC-board amps, the Sunn sounded good and should be reliable.
The audition
An amp that costs $1,700 ought to sound good, right? Well, the Sunn T50C sounds great. Playing an American standard Fender Telecaster through the clean channel, the amp puts out a very full vintage bass and midrange with just a tinge of crispness in the treble, courtesy of the Celestion. Reverb is clean and "Fendery" without spring "boinginess." Clean country pickers, jazzers and rhythm aces will like the palette of sounds available from the clean channel.
The overdrive channel is killer with the ability to create Marshall-like compressed crunch power cords and vintage overdrive of older Fender amps. This is one of the better overdrives I have heard in a modern tube amp. And the low-power mode makes the distortion that much better when playing at home or for recording. Sunn also offers a head/speaker cabinet version as well for a few bucks more.
