Yamaha CH-100 Stereo Chorus

It takes some tweaking as this is an unusual pedal. An old stock ( not modded) Yamaha CH-100 Sound Device Series (SDS). Three knobs; Width, Manual and Speed. All three knobs interact with each other.It is a 2-input, 2-output device. Stereo in and stereo out. Both outputs are "wet". One output is the inverse of the other. There is a glitch from what I can tell as the effect regenerates. The Width knob adjusts the amount of pitch variation of the chorus. In "min" setting it turns into a slap delay with all other knobs set to "min". As you turn the Width knob clockwise it flattens out into a chorus effect. The Manual knob interacts with the setting of the Width knob. When Width knob and Speed knob are set to "min", and the Manual knob is set to "max" there is a slight "enhanced" sound but not an obvious chorus effect as in the usual swirling sound. Turning the pedal off proves there is an effect at that setting. According to the owner's manual the "Manual" knob affects high frequencies in the clockwise position and low frequencies in the counterclockwise positions. 12 o'clock seems to be the transitional point on the Manual knob. I know, it's hairy, but it gets better. Turning the knobs too high and you get a sound only good for noise effects. Not musical in the traditional sense except for electronica. When moving the knobs while there is still a signal present, it will warp the sound like moving the tape head on a real tape delay. Works fine with a PSA adapter but would like to find an original AC adaptor if one was made for this series.The manual says on a 9 volt battery, it should last for 4 hours and has a rated 40mA power consumption. Input impedance is 1-Mega-ohms, input level is +6db and output impedance is 2-kilo-ohms with output level +10db.

Sound is where this pedal makes up for its hard to get knob wrangling. The stereo effect from this pedal is so wide and lush that in a stereo field in my studio, the sound goes beyond the speakers. Rather than the effect just shifting between the speakers, it goes past the speakers left and right! it sounds like it's everywhere around the speakers and the listener. I wonder what it would do for a voice track, widening the stereo field? I played a Tele into the pedal and into a Panasonic DA7 recording mixer going out to Mackie HR824 studio monitors.The CH-100 gets a better sound when only one input is used as opposed to both. There might be a loading problem when both inputs are used simultaneously. I have not tried it with a guitar amps as i acquired this for recording DI. There is hiss-noise out of this pedal and you can hear the effect cycling even when not playing if you listen close to the speakers. In a recording the noise would get buried or if gated. I gave this a 9 rating simply because the 10 rating says "pristine". Other than that I would give it an "11" for having such a wide stereo effect. No other pedal I have approximates this. Ibanez SC10, Boss CE-1,CE-2,CE-5,CH-1,HR-2, DOD FX65, do not have near the width the CH-100 has. And neither do any chorus effect, expensive plug-ins that I have in the Pro Tools rig. The stereo effect is strong and the pedal is not weak when turned on. The owner's manual boasts a frequency characteristics rating of 20Hz to 100kHz. The CH-100 can get weird wobbling sounds that I would find unsuable. From what I can tell, the effect is under the original signal of say a guitar as you can still hear a clean guitar note on top of the effect. The CH-100 sports MN3208, MN3102, LC4066B chips. It was made in Japan and has pink and black knobs and lettering.

Metal heavy duty casing, thick rubber footpad, heavy duty battery box switch and better than average, sticky rubber bottom. Yamaha cannot be faulted for a flimsy pedal on this model. Finding another one of these may be hard so having a backup would be a luxury if not just plain luck. This is an older pedal and still have yet to find production dates on it. Yet it still works, this would make it dependable to stand the test of time. The jacks are recessed without nuts in its own metal flange separate from the pedal housing so getting the jack barrel edge warped from a mishap is less likely than with a Boss pedal.

Since this pedal seems to be discontinued, from what I can find on the net, which is very little, customer support may be extinct for this pedal.

Playing rock mostly this pedal would be good for recording. I was not aware of this model pedal and a friend who provides me with used pedals offered me a CH-100. It came with the original box and owner's manual and two styro formed end protectors. The chorus effect is thick as compared to other chorus pedals and shines in the stereo width department like no other pedal I have come across. I'm not sure what this would be good for in a live situation but in a studio setting it adds hard to come by stereo effects. The stereo width is amazing to say the least and for that purpose alone it's worth its weight. Been playing and recording for a long while, have a cabinet full of pedals, multi effects, software plug-ins and this is a stereo chorus to emulate. I could see using the CH-100 on many different tracks in a recording just to get the width factor. I would definitely look for this pedal if lost. With the stereo inputs, running stereo bounces through the CH-100 upon mix down should provide some eye/ear opening results.