Tube Amps

Category 5 is a relatively new company based in Frisco, Texas that has wasted no time in developing twelve distinctly unique, hand-wired designs ranging in power from 15W–100W, while aggressively placing amps with touring players like Joe Bonamassa, Tab Benoit, Jimmy Thackery, Gary Moore and one of our favorite Texas Burstbusters, Jonn Richardson (Otis Taylor), among others. The company’s strategy for quick and lasting growth is fairly obvious with a quick scan of their website – build hand-wired tube amps to the highest standards of custom manufacturing, and offer a range of power and tone shaping options that will meet the needs of virtually any player, from low volume home and studio applications to 100 watt pro rigs suitable for cavernous venues and big stages. When it comes to fully understanding the intention of Cat 5 amps, you’ll need to do a little homework on each model, many of which are named for famously wicked hurricanes. We’ve done all the work for you on the two models reviewed here….

We received a 1×15 version of the 40 watt Andrew, which is also available in 2×10, 2×12 and 4×10 configurations. The 1×15 is equipped with our favorite current production 15” – the Eminence Legend–along with dual 5881 power tubes and an interesting combination of two separately voiced input channels. Channel 1 is described as having been inspired by the ’61 Fender brown Deluxe. Having owned a dead mint example of this very amp, we can tell you that it possessed a remarkably toneful and middy snarl, but very little usable clean headroom, which is why we ultimately let it go. Channel 1 in the Andrew produces an equally “brown”sound – rich with midrange and none of the typically scooped tones of the black face era.

Channel 1 is designed with a single tone control to shape EQ, plus the global reverb and “voltage”controls for the internal variac circuit. Of course, the reissue Tung-Sol 5881 tubes create a much more formidable voice than our brown Deluxe could ever must, which we consider to be a tremendous improvement to anything inspired by the brown Deluxe. We all experience and embrace varying sounds quite differently, so we won’t offer this as an absolute, universal truth – but to our ears at least, we prefer the tone and attitude of Andrew’s Channel 1 combined with snappy single coil pickups that can impart a stronger attack on the bass strings and happily frolic in the midst of all that midrange. Otherwise, what you hear is the sonic equivalent of a chocolate-chocolate chip double fudge cookie in the style of a late ’50s Gibson GA40– a very good thing with single coils or bright replica PAFs. Dialed in with the sole tone control, you can create a very old-school tone in Channel 1, and that does seem to be its purpose, so mission accomplished. A more nimble and versatile range of black face tones are found in Channel 2.

Channel 2 offers a full range of tone-shaping EQ, with bass, treble and midrange controls, plus the global reverb and voltage controls common on both channels. We asked Steven Scott, head of product development at Category 5to explain….

TQR: Does the voltage control essentially function as avariac, dropping voltage to the power section, or is something else involved (most people have heard of power scaling but have no idea what it really does)? Power Scaling is another name for voltage control. We don’t use the same circuit as London Power and have not licensed the trademarked name, so we can’t call it Power Scaling. The voltage control makes the B+ voltage variable from about 60VDC to about 450VDC, which allows you to dial the amp from about 5W to about 45W. This allows you to more or less keep the same tone once you’ve dialed it in, then scale it to the size of the venue. This is the feature that our customers rave about the most. The tone really does stay pretty consistent until you take the voltage way down below about 11:00 on the dial. Then it starts to brown out as the tubes are operating well blow their intended point. Another advantage of this technology is it greatly improves tube life as the bias drops as the voltage is turned down. It differs from using a variac in that only the B+ voltage is affected, meaning filament voltage stays the same and no damage to the tubes such as cathode stripping can occur.

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