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$352 pledged of $10,000 goal
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$352 pledged of $10,000 goal
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What is a prototype?

A prototype is a preliminary model of something. Projects that offer physical products need to show backers documentation of a working prototype. This gallery features photos, videos, and other visual documentation that will give backers a sense of what’s been accomplished so far and what’s left to do. Though the development process can vary for each project, these are the stages we typically see:

Proof of Concept

Explorations that test ideas and functionality.

Functional Prototype

Demonstrates the functionality of the final product, but looks different.

Appearance Prototype

Looks like the final product, but is not functional.

Design Prototype

Appearance and function match the final product, but is made with different manufacturing methods.

Production Prototype

Appearance, function, and manufacturing methods match the final product.

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Prototype Gallery

These photos and videos provide a detailed look at this project’s development.

About this project

We are bringing the vacuum tube back at the fraction of the weight and size of a tube amp.  This isn’t just a tube simulation circuit; it is the real thing with a 12AX7 tube.

Our goal was a rugged, great sounding “analog” Pre-Amp/DI designed specifically for the acoustic musician. But we wanted to add something special... a dedicated "real tube" circuit that will add a warm and inviting tone without unwanted signal compression. We did it. 

The Ai ProTube is a great acoustic Preamp/DI all by itself but now you can also have the richness of a real “tube.” 

Ai ProTube with 12AX7 tube
Ai ProTube with 12AX7 tube

Why a Tube? 
Acoustic musicians can pay thousands of dollars for a well-crafted and great sounding acoustic instrument. This great tone is often hijacked once the instrument is amplified because of the digital processing of today’s amplifying and recording equipment. The best available device for amplifying audio signals is still the vacuum tube. A tube provides the cleanest, most open, transparent, and musically enjoyable sound possible.

GMF Ai ProTube not only offers an incredible preamp and a real "tube" but is your all around portable solution for connecting your acoustic instrument into a sound source at home, in the studio, or on a gig from a coffee shop to even a stadium.

The Ai ProTube features:

  • acoustic preamplifier with active four band EQ including midshift
  • a DI XLR out to connect to a PA system
  • a line out for recording
  • an input gain control
  • a level out control
  • a mute switch and tuner out jack for silent tuning on stage
  • an effects send and return loop
  • a ground lift
  • a phase inversion switch
  • an overload indicator
  • 24 volt high headroom preamp 
  • and yes a 12AX7 tube circuit activated by a foot switch
Back of Ai ProTube
Back of Ai ProTube

If you don’t have a built-in pickup on your guitar or other acoustic instrument, no problem let us know and we will include a handcrafted transducer pickup to your order. 

Listen and read what our road testers and reviewers are saying about the Ai ProTube:

Steve Rutledge

"Warmth, Dynamics, Saturation, EQ plus an FX Loop? The Ai ProTube has just Raised the Bar for Acoustic Tone!!!" -Steve Rutledge-  (Steve Rutledge and the Groove Evolution) Hear Steve's clip below
"Warmth, Dynamics, Saturation, EQ plus an FX Loop? The Ai ProTube has just Raised the Bar for Acoustic Tone!!!" -Steve Rutledge- (Steve Rutledge and the Groove Evolution) Hear Steve's clip below

 

 John Shaw

"This is it. The mother of all acoustic DIs. The new Ai ProTube from GMF. It is the warmest, roundest, truest to life sounding way of amplifying an acoustic guitar I've ever heard" John Shaw (lead guitarist for multi-platinum country artist Josh Turner)
"This is it. The mother of all acoustic DIs. The new Ai ProTube from GMF. It is the warmest, roundest, truest to life sounding way of amplifying an acoustic guitar I've ever heard" John Shaw (lead guitarist for multi-platinum country artist Josh Turner)

Roger Eaton
"Over the years I have tried a number of acoustic preamps. I thought a few of them sounded really good, that is until I had the opportunity to play through the Ai ProTube. Wow !! What a difference even to the point that FOH engineers were approaching me asking what my acoustic signal chain is.  I could instantly hear a huge difference. For the first time I felt I could actually hear the sound that was inside the guitar, it actually sounded closer to what an acoustic should sound like standing in front of it and not just plugged in to a typical DI. Thanks Greg Farres for a great design in a bullet proof metal package." ⭐️⭐️⭐️⭐️⭐️"  

Roger Eaton, lead guitarist for Oak Ridge Boys, substitute guitarist for Grand Ole Opry band, toured with Tanya Tucker, Lorrie Morgan, Joe Diffie and Barbara Mandrell
Roger Eaton, lead guitarist for Oak Ridge Boys, substitute guitarist for Grand Ole Opry band, toured with Tanya Tucker, Lorrie Morgan, Joe Diffie and Barbara Mandrell

Jeffrey Douglas 
"I love the Pro Tube on my Acoustic guitar but I am using it on my dobro. It makes my dobro stand out in my mix and gives it a rich and fat tone. I love it. It's a great piece of gear."

Jeffrey Douglas (Plays acoustic guitar and dobro for The Oak Ridge Boys)
Jeffrey Douglas (Plays acoustic guitar and dobro for The Oak Ridge Boys)

Zach Runquist

Zach Runquist's beta test unit. Zach plays fiddle, mandolin, banjo, dobro, acoustic & electric guitar, as well as vocals for headline acts. And yep he said the Ai ProTube is AMAZING!
Zach Runquist's beta test unit. Zach plays fiddle, mandolin, banjo, dobro, acoustic & electric guitar, as well as vocals for headline acts. And yep he said the Ai ProTube is AMAZING!

Special thanks to super talented musician Zach Runquist for road testing our products and making the demos below. Zach is a songwriter and musician who has performed and recorded with many artists, including Lee Ann Womack, Craig Morgan, Lauren Alaina, Kristen Kelly & Sarah Darling.

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Dan Carlton (DC Gear Reviews)
 
"This unit instantly breathes life into your recording! I will come clean. I was skeptical that I would use this pre-amp, but Greg at GMF convinced me to give it a shot. I have been converted! I am a believer! :) I love my guitar, but the ProTube is bringing out lush overtones I haven't heard before". (We used his intro for our video! Here are two more clips; for the full scoop click review to go to his YOUTUBE review).

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Michael Spriggs
Check out session musician and producer Michael Spriggs on his Bouzouki, Baritone guitar and 2 more acoustic guitars. 

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Message from designer Greg Farres
"Standing backstage at the Grand Ole Opry, I got a taste of what young musicians must feel like the first time they get to play there. At a sound check just before the show, Jimmy Capps, Nashville Cat and Opry house band guitarist played through one of my Ai ProTubes. He liked it so much that he went on to use it on the televised show
that evening. He told me he would be taking it to Ryman as well. All the hours of design, testing and  hardwork were validated in that moment. Needless to say I was very proud to impress one of the best of the best".  (Greg Farres, Founder and owner of GMF Music)

Jimmy Capps backstage at the Grand Ole Opry
Jimmy Capps backstage at the Grand Ole Opry

 

 

How the Ai Pro Tube Compares            
The Chart below compares the Ai ProTube with some of the popular units currently on the market. As you can see there are two things that stand out. “None” of the competition is MADE IN USA and none of them includes a Tube Circuit. By manufacturing the Ai ProTube in the United States, we have quality control of suppliers, components and assembly. The Ai ProTube circuit brings out the genuine tone of your instrument which you just can't get without a tube.

Comparison Chart
Comparison Chart

The Power of Your Pledge:  We need your pledge to begin full production of the Ai ProTube and with your support this will be our fourth successful Kickstarter campaign. Kickstarter makes it possible to reach the best kind of backer, that special person who wants more and wants to be one of the first to have a new product or technology. Each pledge you make goes well beyond a mere transfer of goods; we want you to fall in love with your acoustic instrument all over again with the richness that only a tube offers. 

Production:  We are proud to say we can source most of the material in the United States. I will personally build and test each unit to be sure you have a quality piece of gear. I stand behind each product and our logo bears my name.

Fulfillment Plan:  This will be our fourth Kickstarter campaign. Products from our first three campaigns were sent out promptly on schedule and are still used almost daily by professional musicians. We have had musicians road testing the Ai ProTube and I can say it was a proud moment when I got to see the Ai ProTube make its Opry debut just a few weeks ago. We will be posting more pictures of artists using the Ai ProTube and their comments.  We are pretty excited that in June their will be 3 Ai ProTubes on stage at the Grand Ole Opry for at least two nights in a row.

 

 

Risks and challenges

What we've built already: Our team has over 37 years of manufacturing and design experience in the music industry. We've already built the core technology and tested it. We ran a successful Beta test using professional musicians then we started a larger test with more professional musicians. The risks and challenges were minimized through quality and rigorous field testing. We can confidently say that there is no technical risk left to the project.

Once we have achieved our goal and the Kickstarter campaign has successfully concluded, we can complete production and fulfill all rewards. We don't foresee any obstacles that won't be solved easily and we will personally communicate to our backers throughout the process. If delays occur, we will always be upfront about them, inform our community of our plan of action, and keep the regular updates coming.

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Support this project

  1. Select this reward

    Pledge $350 or more About $350

    Ai ProTube Early Adopter

    Receive one Ai ProTube ($599 retail value).
    Tube tone for your acoustic instrument!
    Includes one Ai ProTube, one power supply and instructions.

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    Estimated delivery
    Ships to Only certain countries
    Limited 1 backer
    $
    Kickstarter is not a store.

    It's a way to bring creative projects to life.

    Learn more about accountability.
  2. Select this reward

    Pledge $399 or more About $399

    Ai ProTube

    Receive one Ai ProTube ($599 retail value).
    Tube tone for your acoustic instrument!
    Includes one Ai ProTube, one power supply and instructions.

    Less
    Estimated delivery
    Ships to Only United States
    Limited 0 backers
    $
    Kickstarter is not a store.

    It's a way to bring creative projects to life.

    Learn more about accountability.

Funding period

- (40 days)