Li'L Izzy

John Gould · Post by **John Gould** » 25 Feb 2009 9:29 pm

Does anyone know the secret behind the IZZY?
Does anyone still use them and have them ?
Here's a picture of mine. I would love to have another as a back up.

Brint Hannay · Post by **Brint Hannay** » 25 Feb 2009 9:50 pm

I have an Izzy Plus that quit working about 10-15 years ago. (Yes, I know it is battery-powered!) The "works" being entirely encased in opaque epoxy, it is of course unrepairable.

Tony Glassman · Post by **Tony Glassman** » 25 Feb 2009 10:39 pm

One of my friends is a radiologist, I've been thinking of having him shoot an xray of the Izzy's innards. It might show just what's under all that epoxy goop.

Jack Stoner · Post by **Jack Stoner** » 26 Feb 2009 4:10 am

It's got an IC in it, probably an op amp. I had one and it went bad and I tried to get into the potting material.

A Goodrich MatchBox will do the same thing.

Brint Hannay · Post by **Brint Hannay** » 26 Feb 2009 10:39 am

It's funny about that, my theory was the same when my Izzy Plus went bad. I bought a Matchbox from Billy Cooper's, and found it wouldn't do what the Izzy had done at all! The Izzy made the steel sound considerably brighter, "clearer" if you will, but the Matchbox didn't do that, no matter what settings I tried. I don't know why. Fortunately, Billy was good enough to let me return it.

John Gould · Post by **John Gould** » 26 Feb 2009 11:10 am

I would have to agree, I've tried all kinds of different boxes and matcher gadgets and have not found anything that does what the IZZY does. My IZZY seems to do more "cleaning" than anything else I have tried.
More tone all the way around. I have not tried the Shadow pre-amp which I have heard works really well. It's real pricey and I have not found it anywhere with a return policy yet.

Jack Stoner · Post by **Jack Stoner** » 26 Feb 2009 3:54 pm

The Lil Izzy may have a capacitor or even an RC circuit to help with the response but basically it's a 741 OP amp(the common op amp used in that era) that provides a high impedence input load and it's output is a low impedence that can drive "miles" of cable. They did a demo with the Lil Izzy and some low Z cable and it drove an entire reel of George L's cable in a Demo at St Louis one year and there was no loss.

I have a small MXR MicroAmp and it does basically what the Lil Izzy will do. I never compared to the tone of the two so it may be like a MatchBox - doesn't compare to the Lil Izzy.

John Gould · Post by **John Gould** » 26 Feb 2009 4:25 pm

Hey Jack you don't by chance have any schematics on circuits that use that op-amp in a unity gain type circuit that could run off a 9 volt supply. I figured it had to be a extremely high impedance input, didn't know on the other side, so the pickup didn't get loaded by anything on the other side of the IZZY. It can't be much because of the size of the potting. It looks like everything is grounded to the box the input side goes straight into the potting and the jack switches the 9 volts to the circuit.

John Gould · Post by **John Gould** » 26 Feb 2009 4:50 pm

It's the output that comes out of the potting.
My mistake on previous post.

Jack Stoner · Post by **Jack Stoner** » 27 Feb 2009 4:18 am

John, let me look around and see what I can come up with. I think I have a schematic of the MXR MicroAmp.

John Gould · Post by **John Gould** » 27 Feb 2009 8:42 am

Hey Jack I found something on the MXR but I think I might have found the secret of the IZZY with your help.
I went and researched the 741 op amp and did a little experiment last night and I think I'm on the right track. Anyway here's a Schematic for the MXR I found on the net.

John Gould · Post by **John Gould** » 27 Feb 2009 8:45 am

Hey Jack I found something on the MXR but I think I might have found the secret of the IZZY with your help.
I went and researched the 741 op amp and did a little experiment last night and I think I'm on the right track. Anyway here's a Schematic for the MXR I found on the net.

John Gould · Post by **John Gould** » 27 Feb 2009 9:36 am

Here's what I have so far, I think I'm getting close
it seems to work I need to refine the circuit some but maybe with Jack's help I can get closer.

Jack Stoner · Post by **Jack Stoner** » 27 Feb 2009 11:30 am

I don't have much info on those old op amps anymore. I'll have to go through the schematics that I do have and see how they are used.

I don't even know for sure if that's what is used in the Lil Izzy, just that the 741's were commonly used in the era it was manufactured.

Ernie Renn · Post by **Ernie Renn** » 27 Feb 2009 1:36 pm

Maybe try Brad Sarno's new impedence matcher box, The Freeloader! I haven't tried one, but did use a Lil' Izzy for years and also a Matchbox. Seems like it might be worth a try. For that matter his Steel Guitar Black Box is said to be a very nice tone inhancer, as well.

Jack Stoner · Post by **Jack Stoner** » 27 Feb 2009 2:39 pm

The Lil Izzy is a solid state Op-Amp type unit, not a tube unit.

Michael Maddex · Post by **Michael Maddex** » 27 Feb 2009 8:08 pm

John, I have never used and don't know anything about the Li'l Izzy, but maybe this will help you out anyway. A couple of years ago I was fooling around with some piezo contact pickups, which have very weak output, and I needed some kind of preamp. I guess I could have bought a commercial unit, but I was interested in learning about op-amps, so I opted to make a preamp and I used a 741 like you and Jack have been discussing. Here's the basic circuit I ended up with:

There is a little more to it than what is shown above. There's an LED to indicate power on, a tone circuit, and the switch is actually a stereo jack for the input. What's shown is what I started with and does work. The gain is a ratio between R1 and R2, so I imagine a pot could be used there instead of at the output where I have it.

HTH.

Herby Wallace · Post by **Herby Wallace** » 27 Feb 2009 8:28 pm

Well, I thought I would chime in here a little bit. First, I know very little about electronics and don't claim to, but I have been using one of these units since the early eighties when they were first introduced. I have compared it to the Goodrich Matchboxes and some other similar units and to my ear the Izzy is by far the cleanest of them all. I still have one in my pak-a-seat right now. Craig Baker who designed this unit, is a friend of mine and what I call an electronics "Whiz". I even tried an amp he built one time back in the eighties and it was unbelieveable too. I have been trying for years to get him to start back building these units and hopefully someday he just may. When I use effects boxes which I do from time to time, I have to use the Izzy to keep from losing my tone before it gets to the amp. I just wanted to give my opinion about this great unit since I still use one. I sold them for many years in my shop so maybe I can talk Craig into making them again.

Herby Wallace

John Gould · Post by **John Gould** » 27 Feb 2009 10:12 pm

Maybe you could get Mr. baker to reveal the secret behind the Li'l IZZY if he is not willing to build them again. Or offer to sell a kit or the schematic for it or something to help us out with or tone. I bread boarded up something last night with a 741 op amp and it worked pretty close but I'm missing the secret ingredient.

Jack Stoner · Post by **Jack Stoner** » 28 Feb 2009 3:00 am

I don't really have anything to offer. I looked at the schematic I made of an early MXR microamp, that I had, and it uses and LF353N Op Amp. A schematic that I found on the web used a newer Op Amp so it probably used differnt Op Amps over the years.

The key to the Lil Izzy is that it's basically an isolation device that has a low impedence output. It doesn't do any amplification, etc.

I remember the time in St Louis when it was demonstarated, Herby was endorsing it and was the one that did the demo of driving a whole roll of George L's cable.

Just remember the 741 is just my "guesstimate" of what was used.

John Gould · Post by **John Gould** » 1 Mar 2009 7:46 am

Hey Jack I think you made a good guess. I'm pretty close to the Izzy sound. It would be great if Mr. Baker would start building again or make the design public so we could build our own. Maybe Herbie can get him to do something one way or the other. Maybe Ken fox has a design or one of the other electronics guys out there. Thanks to everyone who's thrown their ideas in the ring here.

c c johnson · Post by **c c johnson** » 1 Mar 2009 8:58 am

I used an izzy when they first came out and I was in a rock band. The guitar player was not reliable and when he was awol I used the izzy to get those screaming rock sounds out of my sho-bud. As soon as the band got a new guitar player I quit and threw the izzy into the Brazos river. cc

John Gould · Post by **John Gould** » 1 Mar 2009 6:39 pm

Did the IZZY sink or float?
Should I dredge the Brazos?

Brad Sarno · Post by **Brad Sarno** » 1 Mar 2009 6:51 pm

It's hard to know for sure what's under the goop, but the few circuits you guys are proposing here have WAY too low of an input impedance with those 47k resistors. The Izzy likely had a very high (maybe 1Meg) input impedance to get that crystal clear top end. Or maybe even some treble boosting. Hard to know what's under the goop. I'm guessing it's a simple opamp buffer circuit with a real hi-z input. Maybe has a couple of tantalum cap's to add some of the crispy zing to the top end (as well as being small enuf to fit in the goop). Just guessin'.

Brad

John Gould · Post by **John Gould** » 1 Mar 2009 7:09 pm

Thanks Brad, I'm out to my workshop and get out my resistance substitution box and try some different values on the front end. That may be the ticket.

The Steel Guitar Forum

Li'L Izzy

Li'L Izzy

Brint

741 op amp

Output mistake

Micro Amp

Micro Amp

Izzy close

op-amp circuit

Li'l Izzy

Mr Baker

thanks

Thanks Brad