Gizmotron 2.0 revisited on Fretless Guitar


Gizmotron fitted

Well I finally mounted the Gizmotron permanently on my Crop Circle guitar. It works really well but takes some getting used to, like having to play a small keyboard instead of using a pick.

As mentioned in the previous article the Gizmotron is set up with 3 wheels for wound strings and three wheels for plain strings, the Crop Circle is fitted with 13’s and has 4 wound strings and 2 plain strings. It is tuned down a whole tone across the board. (D tuning: D G C F A D) Things still work fine but you miss the attack you would get on the third string that is so present on the three lower strings.

So I sent off to Gizmotron for a set of wheels to try out a better suited wheel for the G (sorry now F) string. Really quick service, ordered Friday arrived Tuesday, that’s from the US to the UK.

Fitting the new wheel for the third string was a little fiddly, you need three hands really. The pack of wheels stated New and Improved so I also swapped out the 1st & 2nd string wheels. Well that made a big difference. The balance across the strings being greatly improved.

Had a really fast reply from support at Gizmotron. You can buy any quantity or types of wheels by emailing the standard pack is 3 + 3 wound and plain.

Round wound vs Flat wound strings

The next thing I wanted to try was a set of flat-wound strings to see if that made the attack a bit more mellow.

Gizmotron removed

To change the strings the Gizmotron must be removed from the guitar completely, very easy as it is held in place with three allen bolts. You can see the adhesive stickers have pull tabs. These are to remove the sticky tab from the guitar should you need to, it does destroy the tab but leaves the finish on the guitar intact.

I took off the old strings and noticed quite a bit of gunk from the wheels rubbing the strings and wondering what the life expectancy of the wheels would be. The new strings were Thomastic Infeld Jazz Swing JS113. (Gizmotron recommends .009 strings but the guitar is set up for .013 strings) Neck radius is 17 inches.

What an improvement! Gone was the rasping noise on the round wound strings. If you are using a Gizmotron I would highly recommend Flat wound strings.

Noisy motor

Oh, and one other thing; the sound of the Gizmotron motor is so annoying, I’m sure they could have made it quieter if they used better gears etc..

Update on noisy motor:

Had a very quick reply from Aaron, tech support at Gizmotron. The noise is generated from a faulty bearing and Arron is sending a new shaft and bearings out to me. More when it arrives….

Fitting a new shaft and bearings:

Well the response from Gizmotron was fast, emailed Friday and the parts arrived in the UK the following Wednesday.

Fitting was really easy, just remove five screws and the speed control, pull off the cover, lift out the shaft and replace with the new one.

Here’s a short before and after video, and no, I did not turn the sound up, it is the camera’s AGC doing that. The difference is quite dramatic, it still makes some noise but this is minimal. Job done, I’m happy.

Speed settings

Generally I have the speed set at about one third which seems to give the widest range expression-wise. At full tilt it can be quite aggressive and I have not got my right hand fingers up to speed to take advantage of that. At the slowest speed it is also very usable.

Power consumption

The power required when the motor is running is quite low, 1ma at slow speed rising to 4ma at high speed and a maximum drain of 14ma under full loading of all strings. So a small USB battery pack would last a long time and would be a good solution for stage use.

Using a volume pedal

This is almost a must for using this device, while you can get nice bow attack sounds without one but you cannot get that swelling bow sound without a volume pedal.

Hints & Tips

The three screws that adjust the height of the unit can spin quite easily when taking the device off the guitar. Lock them in place with a little soft Loctite or a drip of candle wax. This makes the unit easy to remove and replace and keeps your height settings correct.

Change one wheel at a time, on the guitar version each key is numbered from 1 to 6 and they must be mounted in the correct order!


Flat wound strings make a big difference, the “New and Improved” wheels are worth getting hold of for the better response on the plain strings.

Technical response from Gizmotron is really fast and helpful, full marks!


Gizmotron 2.0 and the Fretless Guitar

Gizmotron website

3 thoughts on “Gizmotron 2.0 revisited on Fretless Guitar

  1. Noisy motor update 24/Aug/2018 to be resolved by Gizmotron support team
    Added fitting the new shaft and bearings c/w before / after video 1/Sept/2018
    Added Hints & Tips 3/Sept/2018

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