TECH TIPS: The Halcyon Green Overdrive’s ADAPT Switch – What It’s Really Doing For Your Tone

August 19th, 2022 |  John Dines

 

Hopefully by now you’ve spotted our latest pedal release, the Halcyon Green Overdrive. In fact, if you’re part of the online guitar forum community, you may have even been part of a discussion about why we’ve made a pedal inspired by the Ibanez® TS808 Tube Screamer®, and what we could possibly offer that hasn’t already been done on the previous million and one clones of that famous green pedal.

The answer is simple – our new Adaptive Circuitry. It’s what makes our pedal different from any other, and it’s also what made it impossible to just clone the circuit and make a few tweaks. We designed it from the ground up, then voiced it to sound like the classic TS808, so that we could give it the unique ability to change its voicing – as well as the amount of drive – as you clean up from the guitar volume control. To understand why this is a big leap for the Tube Screamer® sound, and why you’d want to clean up from the volume knob, we’ll delve into what’s going on in that classic overdrive circuit.

Let’s start with the most fundamental part: how the overdrive is created. In any bit of audio gear, when the signal is too big for the next device in the circuit to handle, that next device simply chops off the top of that waveform at the maximum size it can handle. This is called clipping and is what we are hearing any time we dial in a “distorted” or “overdriven” guitar tone.

In the TS808 – and most drive pedals, for that matter – the clipping is provided by diodes, configured in a “soft clipping” arrangement. This means the clipping of the waveform is more gradual than a “hard clipping” circuit, resulting in the warmer, more natural tone we associate with lower gain drive pedals. There isn’t that much of the signal being clipped either, making the circuit great for lower-gain drive tones. This should also make it a good candidate for cleaning up with the volume control.

Because the TS808’s diodes always clip the signal at a certain level, we increase clipping by pushing more signal above that level. This is what the Drive or Gain control on a drive pedal is doing – pushing more signal into the clipping circuit and above the clipping threshold. By reducing the signal level going into the clipping circuit, we can drop it back down below the clipping threshold and return to our clean sound.

It’s just the same on a valve amp, or any other circuit you might be overdriving. So why don’t we just turn amps up all the way like in the old days? Why doesn’t cleaning up with pedals feel the same? Why do we use pedals to vary the level of overdrive anyway? The answer is largely in the voicing.

With a clean guitar sound, it’s usually desirable to have a broad frequency range being amplified. The low end provides weight and depth, while a nice helping of treble retains detail, articulation and sparkle. However, when we start overdriving that tone, all that low frequency content stops being helpful and instead turns into mushy, flabby low end. At the same time, all that shimmering treble reveals the ugly, fizzy edges of our clipped waveform. As usual with guitar, there’s a compromise to be made: big, full clean tone or tight, warm overdrive?

This is a big factor behind the popularity of overdrive pedals. You can set your clean (or almost clean) tone just the way you like it. Turning on your drive pedal not only clips your signal and creates overdrive, but it can also shape the EQ of that signal, leaving you with an overdrive tone that works, rather than a fuzzy, mushy mess. This is the key to the TS808 tone; it removes bass and treble, amplifying just the remaining midrange, giving it its classic “mid-hump” tone. This is particularly handy when boosting an amp into overdrive, as the amp doesn’t receive excess bass that would result in a flabby tone, and the rolled-off treble means your amp’s bright clean tone won’t have any fizz to accentuate when you step on your pedal.

So far so good. Dial in a big, fat, chiming edge of break-up tone for rhythm, then jump on your TS808 for leads, pushing those lovely mids into your amp, while sparing it the flub and fizz. Both extremes covered, but what about everything in between? This is where a great many players reach for the guitar volume knob to clean up, or simply adjust their picking dynamics to reduce the signal going into their rig. We already know that rolling back the volume knob will drop your signal down below the point of clipping, cleaning up your tone. We also know that overdriven sounds benefit from the removal of bass and treble, whereas clean sounds work better with a fuller frequency range. How far can you clean up your mid-forward TS808 tone before you start wanting your bass and treble back?

Not very far is the answer, and that’s where our ADAPT switch comes in. In the Halcyon Green Overdrive, it’s not just the clipping that reduces as you back off the guitar volume or playing dynamics. It also reduces the extent to which bass and treble frequencies are removed. This means that, the cleaner the pedal gets, the more of your guitar’s frequency range is restored!

Examples:

Audio 1: Here’s our clean sound

 

Audio 2: Stock TS808 setting, no ADAPT, guitar volume on full

 

Audio 3: Halcyon Green Overdrive, ADAPT mode II, guitar volume on full

 

Audio 4: Stock TS808 setting, no ADAPT, guitar volume dialed back for a clean tone

 

Audio 5: Halcyon Green Overdrive, ADAPT mode II, guitar volume dialed back for a clean tone

 

Make no mistake, this took months of head-scratching and testing to perfect, all to give you something that can be dialled in easily and felt instantly. Crank your guitar all the way up and you’ve got that classic TS808 mid-hump drive tone (probably the most popular drive tone of the last few decades). Turn your guitar down or pick softer and you’ve restored all the fullness and sparkle of your clean tone, almost as if the pedal wasn’t even on.

What was once an all-or-nothing, on-or-off decision that forced us to turn over dynamic control to our pedals is now a continuously variable and expressive part of your playing. One that puts you back in charge of your dynamics – like when you plug straight into a great amp – but with all the advantages that the tone-shaping of a great pedal can provide. Because we like an extra feature here at Origin, we’ve even given the Halcyon Green Overdrive two levels of adaptivity – one that restores the full bandwidth of your clean tone and one that still retains a little bass and treble roll-off even when cleaned up (which can be pretty handy if you still want to “tighten up” the tone a little, or manage unpotted pickups that can get squealy under high gain).

Of course, you can turn the ADAPT switch off altogether and run it like a real TS808 – but we don’t think you will.

For the full product video, follow the link below:
http://https://www.youtube.com/watch?v=6Yn4gSew41Q&feature=youtu.be