# EHX 8 Step Program and Pedals with Expression In



## mister.zed (Jun 8, 2011)

Disclaimer: I really love pedals that change the output signal or evolve over time. Even a small variation in sound can be very expressive. Or happy accidents can happen. So I dig sweeping filters, envelope filters and pedals with expression pedal inputs. I also love LFOs (low freq oscillators).

Because of this, I was very excited about the Source Audio Universal Expression pedal. While I was waiting for that to be released, I saw an Electro Harmonix 8 Step Program on Kijiji for a great price. And since it was the LFO capability I wanted anyway, I snapped up the EHX 8SP.

The 8SP is basically a tap-tempo 8-step sequencer that can output either a CV (control voltage) or a resistance (as in an expression pedal). You can quickly design your own LFO with the sliders or set it to Random.

Right now I have 3 pedals with expression pedal inputs: the WMD Geiger Counter, the EHX Deluxe Big Muff Pi and the Strymon Timeline. The Geiger Counter is mostly a harsh distortion/fuzz noisemaker pedal and being able to insert small jabs of bit-crushed noise every so often is a ton of fun. On the other hand, the Big Muff can be made to sound like a sequenced wah fuzz.

I'm dying to try other expression pedal capable pedals with this set up - particularly the Source Audio Stingray Multi-Filter. Are there any recommendations for pedals that have really musically useful expression pedal inputs? Also, I haven't used the 8SP with the Timeline yet; any suggestions for things to try? On the Timeline I can assign any parameter(s) to the expression pedal.


----------



## exhausted (Feb 10, 2006)

Delay isn't great for it (I had an 8-step briefly) but perhaps on of the patches that has a filter on the delays)

Things that work well
- pitch shifting (EHX pitchfork)
- filters (stepped wah, etc.)
- volume (pattern tremolo)


----------



## mhammer (Nov 30, 2007)

There are a plethora of effects with filter-like traits, such as phasers and flangers, that hold up nicely, when modulated by sequencers or S&H random voltages.

Note that, since the 8Step outputs a voltage and does not provide a proportional resistance, as the Source Audio controller does, there are some limits as to what you can use it with, on its own. Certainly, you could use the 8Step to drive an optoisolator or LED/LDR combo to accommodate those pedals whose "expression" control assumes simply a variable resistance to ground (like Line 6 pedals), but you can't simply plug the 8Step directly into those expression jacks.

One thing you can do, albeit with some external circuitry required, is to combine the 8Step as one of several control-voltage sources. So, you implement a simple CV mixer, which is plugged into the device under control, and feed the 8Step output to one of the mixer's inputs, and adjust the relative levels of that and any other modulation CV you want to use. So, that could be another modulation source, like an LFO, or a random voltage, or an expression pedal that outputs a voltage itself.

Alternatively, one of the "inputs" on the CV mixer can be an offset control. The 8Step has a Depth control, which essentially scales the output level of the pattern up or down. Okay, scale it down a bit. The suggested offset control would allow you to keep that scaled-down pattern, but move the range it takes place in upwards or downwards. An expression pedal could be used to do the same thing.

The possibilities are endless.


----------



## mister.zed (Jun 8, 2011)

Thank you both - there are some great ideas there. And with a few parts and some soldering time it sounds like I could cook up a little auxiliary box that really expands its capability. I really like the idea of a CV mixer. But there was something in the 8 Step's manual that led me to believe that it did both CV and variable resistance:

"Comes supplied with a TRS cable for expression control. Use a standard ¼” TS instrument cable for CV control (0-5V)"

I had assumed there was a digital pot in there along with the CV and it was switched by using different plugs. I'll have to measure it with a multi-meter when I get home and report back.


----------



## exhausted (Feb 10, 2006)

Here are all the pedals known to be compatible.

http://www.ehx.com/assets/8-step-compatibility-list.html

You can plug into the Line 6 pedals and adjust the depth accordingly.


----------



## mister.zed (Jun 8, 2011)

Nice! I hadn't seen that list. I have the Boss SL-20 but hadn't considered it. I actually forgot it had exp in. I'll try that tonight. Thanks.

I'd love to try it with the EHX Riddle or Enigma too.


----------



## mhammer (Nov 30, 2007)

From the EHX site: "Compatible expression inputs must accept a voltage source as the controlling signal. The expression input should also allow for an expression pedal TRS plug with the following connections: Sleeve = Heel, Ring = Toe, Tip = Wiper. The expression voltage present on the Ring of the TRS plug sets the maximum range of the controlling signal; this Ring voltage must be between 2VDC and 9VDC."

I will note that the Source Audio Hot Hand controller provides for both CV and resistance control.


----------



## exhausted (Feb 10, 2006)

mhammer said:


> From the EHX site: "Compatible expression inputs must accept a voltage source as the controlling signal. The expression input should also allow for an expression pedal TRS plug with the following connections: Sleeve = Heel, Ring = Toe, Tip = Wiper. The expression voltage present on the Ring of the TRS plug sets the maximum range of the controlling signal; this Ring voltage must be between 2VDC and 9VDC."
> 
> I will note that the Source Audio Hot Hand controller provides for both CV and resistance control.


And from the manual just to re-iterate. Both voltage and resistance control are possible.

"EXP/CV OUT JackThe 8-STEP’s sequence is output through this jack. When connecting to the Expressioninput on an external pedal or other device, normally you will want to connect the TRS cablethat came supplied with the 8-STEP to the 8-STEP’s EXP/CV jack. If you are connecting the8-STEP to a CV input, use a standard ¼” mono/TS instrument cable instead, the same typeof cable you would plug into a guitar. When a TRS cable is plugged into the EXP/CV OUTjack, the 8-STEP works as a replacement for a typical expression pedal with the followingconnections: TIP = potentiometer wiper or output signal, RING = Toe position andSLEEVE = Heel position. This is the standard polarity for the TRS plug of an expressionpedal that many in the industry follow including all EHX products as well as Boss®/Roland®,Moog®, Nord®etc. Tip: To work properly with devices that accept 3.3V as their maximum,such as Eventide®products, set DEPTH to 5."


----------

