Line Splitter/ Switcher

Jerry isolated his tuner completely out of the "guitar to amp" signal. He utilized a switcher/splitter that he could toggle between his tuner and amp hum-free, and silently. He started doing this in the early 70's up until his final performance. Here is an example of how it would have been wired.



The Onboard Effects Loop (OBEL)

This is Jerry's explanation of the OBEL in October of 1978. This interview actually is the second version of the OBEL as the first did not have a bypass toggle onboard the guitar. The first OBEL also did not have an onboard buffer and used the effects buffers as the additional line driver.

What's the purpose of the two jacks on the front of the Irwin guitars?

That's the one real wiring innovation, a very useful one, It allows me to have all my effects pedals wired to the guitar with the ability to bypass them all with a switch. I use a stereo cord, and the signal goes from the pickups to the tone controls and the pickup switch, and on down the "A" side of the cord to a network box that controls a Mu-tron octave divider, Mu-tron envelope filter, MXR Distortion Plus, MXR phaser, Mu-tron wah-wah, and an analog delay. The signal goes through the devices, back into the network box and up the "B" side of the cord, back into the instrument before the volume pot, and then out to the amp.

What's the advantages to this setup?

All those gadgets are voltage-sensitive. If you have them after the volume control, their behavior is affected by the loudness setting on the guitar. With my system, on the other hand, the effects always see the guitar as if it had a full output voltage. The effects are also controlled by a DC power supply rather than batteries. Since the effects input voltage - the guitar's output - is alway's fixed, they behave exactly the way I want them to. the whole thing is so stable that it's completely repeatable in every situation, and i never run into a weirdness of any sort. I'd used effects in recording before, but they were always too unstable for me to use onstage until we came up with this. If something goes wrong with the effects, or if I want them out of the circuit, all i have to do is flip a switch to completely bypass them without a jump or loss in gain at the amp.

- Jon Sievert Interview Guitar Player Oct 78


Network Box & Cutler Effects Switching Unit

Jerry used the "Network Box" from the beginning of the OBEL(Dec 31, 1976) until the custom Cutler Effects Switching unit was introduced with Tiger August 4, 1979. The Cutler Effects Switching Floor & Rack unit used Relays to True Bypass each effect individually In and Out of the chain. It contained a DC power supply that ran individual DC power jacks for each Effects position if needed. It also had 2 stereo jacks on the back of the rack unit, those jacks cables ran all the way to the 2 floor units, one for each. These were for remoting a potentiometer of an effects pedal, but per Cutler, they only used one of these lines. That line was for the MXR Phase 100 Phase Sweep Rate which was remoted to a Roland FV2. The 2 floor units, one on each side of the Mic stand, were the racks remoted switching unit that controlled the relays in the rack unit. 4 switches each, one for each effect position. In 93 with the introductions of the "90's" rack, a new Cutler Switching unit was employed. It had the same functions as the first, but with IN and OUT LED's on the front of the rack unit, and the 2 remote floor units were consolidated into 1 unit that sat on stage right of the Mic stand. The Effects order was, with both Racks, Top Shelf/Row 1 - 4 and Bottom Shelf/Row 5 - 8.




Strings Used

How do you string your guitars?

With Vincis. They package up a special set for me consisting of a .010, .013, .017, .027, .037, and .047.

- Jon Sievert Interview Guitar Player Oct 78


NOTES: Per Steve Parish, later Jerry would go on to use a .049 and sometimes a .050 for the low E string. Gary Brawer also stated, Jerry sometimes used a .011 for the high E string.


Pick & Right Hand Technique

How do you approach right-hand technique?

Generally I use a Fender extra heavy flatpick which I sometimes palm when using my fingers. The way i hold the pick is a bit strange, i guess. I don't hold it in the standard way but more like you hold a pencil. I think Howard Roberts describes it as the scalpel technique. The motion is basically generated from the thumb and the first finger rather than say, the wrist or elbow. But i use all different kinds of motion, depending on whether I am doing single-string stuff or chords.

- Jon Sievert Interview Guitar Player Oct 78


Note: Later Jerry would go on to use the Adamas 2mm Graphite pick

Dunlop manufactures these picks today and when available can be purchased through them here.



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