Review : TC Electronics Sentry

When we head into the guitar shop and wander over to the pedal area, noise gates are usually not the first or even the second place we look to.  My buddy Cody Shaw, over at The Arts Music Store, is a great player and a strong metal advocate.  The Boogie Rectifier stack is a clue.  We were talking one day about pedals, after he had done a free pedal clinic for customers and he mentioned that he felt a really under appreciated pedal was the noise gate.I have owned a Boss NS-1 gate for a long time (since replaced by the NS-2), but at the time of the conversation had to admit that it was in a drawer because I never really "got" a lot of value from it.  Cody shared that while the Boss is a staple, he likes it better for amplified acouustic guitar.  I tried it there and it has stayed on my acoustic board since then.  I still wanted to get the point about a noise gate for electrics, and Cody encouraged me to try out the TC Electronics Sentry.  He said the best part about it was the Toneprint capability common to so many TC Electronics products.I put the Sentry on the board that I share between the Koch Multitone, the PRS Dallas, the Marshall Custom Super Lead and the Marshall Silver Jubilee.  I do this via a Voodoo Lab Amp Selector.  Sadly this superb piece of kit has been discontinued.To understand the benefit of the Sentry, it's probably worthwhile to quickly explain the idea behind a noise gate, or gate as it is sometimes referred to.  The principle is simple.  Once an audio signal drops below a certain level, the gate "closes" or eliminates transmission of the signal.  If you've ever plugged a vintage guitar with single coils into a tube amp, you've heard single coil noise.  When you are playing, you don't notice it because it's level is so far below the level of the music, but when you stop playing and the only signal is coming from the pickups at idle, it sounds like a bus coming at you.  If you, like me, use a compressor in order to maximize your working dynamic range, or use a dynamic range expander in post production, you understand why you would want to gate off that low level noise.A noise gate typically uses a VCA (Voltage Controlled Amplifier) to determine when to cut the signal.  Sophisticated studio insert noise gates will have multiple controls.  The Sentry has three and they are all most folks are going to need.  The Threshold control determines at what point the gate kicks in (the threshold - go figure).  The more to the right you turn it, the lower the signal can be for the gate to kick in.  If you want long sustain, you will go to the right.  If you want that metal flavoured signal / no signal hard stop, you would go more to the left.  Personal taste of course.  The Damp control is often determines how much signal attenuation gets applied when the gate is activated.  A good place to start is with this all the way left and then tune to suit your preferences.  The Decay control defines how quickly attenuation gets applied to the signal once it drops below threshold.  Start with this all the way to the right and then adjust to taste.I reference adjusting because I have found different settings to be applicable to different pickups, even to different versions of the same model.  Single coils tend to benefit from more aggressive settings than humbuckers but it's really up to you.  I find that P90s are more finicky for me than vintage Fender single coils, and humbucking pickups give me more latitude, but I need a bit more gating on a hollow-body with humbuckers.  Your mileage will vary.The Sentry can work inline or in a send / return loop.  I have mine inline because I use the same board with multiple amps and two of the amps do not have a send return loop at all.The microswitch offers three settings; Gate, Toneprint and Hiss.  The Gate setting is a hard gate and a quick set of tests will illustrate what this means.  Hiss is a setting designed to reduce noise as a result of hiss in the signal.  My preference is the Toneprint setting.  It's a bit more work because you need the Toneprint app and a USB connection to your computer to make adjustments to the Toneprint settings.  I found the factory default to actually be very good as a starting option for my uses.   You can find Toneprint options on the Sentry page.A noise gate may not be the first pedal that you think of when you hit your guitar shop, but if you play with noisy gear, and definitely if you play live without a great sound engineer to fade your signal out when you aren't playing, a properly configured noise gate makes a huge difference and in my opinion the TC Electronics Sentry is an excellent choice.