Gerlt Technologies makes hundreds of customizable rack effects, at prices comparable to guitar pedals.  It's time to dump that pedal board and get Your Tone off the floor!


 What We Do

You know them as guitar pedals

We build them as rack effect modules you can customize to get Your Tone

Put several rack effect modules into a 3U rack enclosure

Connect power and audio on the back like guitar pedals, adding connections for remote switching

Add a remote footswitch unit to turn rack effects on and off

Add as many rack effect modules, enclosures, and third-party products as you like. Plug in your guitar and amp. Rock it! It's that simple.


Quick Hits:

  • Check out our GT Effects Overview to see why we do this

  • Check out our Compares To charts to see the full list of effects we offer

  • Follow the menus from Products, to Modules, to Modules By Type to get a list of our effect types.  Select any effect type to get a list of all our effects of that type.  Select any effect to get full information including pricing.



Hello Effects Fans!

It has been a while since my last update.  Our status has not changed much.  We are still unable to take new orders.  I’ve personally been off doing something completely unrelated, lots of fun, a long ways from home.  That has gone well, but is taking longer than expected.  Instead of finishing up about now, it appears I won’t finish before late Spring or early Summer.  Our status won’t change before then.

Parts availability and cost were primary causes of our current shutdown.  We use around 6500 different vintage and current production parts to build our rack effects.  It has been difficult to find good vintage parts for a while now, and it gets a little more difficult each year - nothing new about that.  Counterfeit and reject parts flood the market, and prices have soared as caches of legit parts dwindle.  The good news is that vintage parts are often not needed to get great-sounding effects.  Usually there are newer parts that will work as well or better if you can get past the volumes of misinformation and hype out there.  Listen with your ears, not your eyes!

Lack of current production parts forced us to stop taking orders.  Some critical parts do seem to be available again, at an increased price.  We want our rack effects to be affordable, and increased part prices are not helping with that.  For example, one part we use in nearly all of our modules, sometimes several per module, went from about 80 cents to around $5+ each.  Really?!?!  Fakes are also flooding the new parts market to fill the demand of the unwary.  However, a few parts are trending down in price.  In these cases there were too many manufacturers, and none of them were getting enough market share to make larger quantities to help reduce their costs.  Some have gone out of business, leading to consolidation and lower production costs.  We’ll take a cost reduction (and pass it along) anytime we can get one!  I’ll have to sort through our hundreds of effects and countless options to determine any impacts to our pricing.  My goal is to remain comparable to pedal prices.  Or better!

Where does that leave us?  The situation has improved, but we still cannot take new orders.  I’m going to work to finish up my side adventure.  I’ll pop up again, probably around June or July, and see how things are looking and provide another update.  

Best wishes for 2023 !!!

Bill Gerlt

President, Gerlt Technologies

Dallas, Texas

28 January, 2023




Hello, Effects Fans!

Today we announce our new Moonquake module.  The GT Moonquake compares to the 4ms Tremulus Lune optical tremolo.

The Tremulus Lune appears to be discontinued from 4ms Pedals, although you may still find a new one here or there.  3ms and Commonsound are earlier names for 4ms Pedals, and some early Tremulus Lune builds show those brands.  The pedal was also sold in kit form and became popular in the DIY pedal-building community, leading to many other "brands" and versions of the circuit, from builders of all skill levels.  Kit builds are sometimes available but may be of widely varying quality.  Even the production builds vary in quality, some of which perhaps shouldn't have been released due to build quality issues.  We've only seen a few of these pedals, all of which had dodgy construction.  The brand new one we purchased for testing is noisy enough to not really be usable, probably from layout and construction issues.   

So how did the GT version turn out?  

First, tremolo is probably the simplest effect there is.  You can do much the same thing by just turning the volume up and down, which is really all tremolo is.  Even in the GT world of customizations, this circuit goes well into "tweaker paradise", with 6 controls instead of the normal 1 or 2.  That's pushing it for regular use, but convenient for when you're searching for "your tremolo".  We like our tremolo simple, so we're a bit at odds with the purpose of this circuit.  Many, many players enjoy this tremolo, so our opinion is just one.

Setting aside the amazing array of controls, how is it?  Well, to us it is still a noisy circuit.  However, there is a Gain control that lets you dial down the gain AND the noise.  To get to "quiet" you have to dial the Gain to "barely on", which might get you below unity volume, or pretty close to it.  Once you dial back the Gain to unity volume or minimal boost, the circuit becomes much more manageable.  We won't attempt to describe the huge variety of tones you can get by adjusting those other 5 knobs to the millions of potential settings.  It's hard to imagine that you can't find your tremolo sound in there somewhere.  Can you find it twice is maybe the more interesting question.

Most tremolo circuits have only a couple of controls, but the Tremulus Lune has half a dozen, most rarely found on any other tremolo circuit.  It's odd to think of that many ways to control volume changes, but they are there.  The Tremulus Lune circuit has some popular modifications that are included.  The first is that external Gain control, instead of the normal internal trimmer.  This makes it easier to adjust for unity volume, or other volume settings for that matter.  The Gain gets pretty high and can lead to distortion if you crank it up.  Cleaner settings are in the "barely on" range of the Gain control.  It is also key to controlling the noise in the circuit.  All those controls are a tweaker's paradise, providing options that we haven't seen in other tremolo circuits.  It can take a while to find settings you like, but maybe also the wide variety of unusual settings will provide you with some unique effects that you enjoy.

You can see more details about our Moonquake module at: Moonquake.  Or look for it in the Tremolo Modules section under Products -> Modules -> Modules By Type.