KMA Machines Stereo Headphone Amp Pedal

A few years ago, KMA released ENDGAME, which is our ultimate end-of-chain utility device. Featuring IR Cab Sims, Power-Amp simulation, True Stereo Doubling, Stereo FX Loop, Aux-in, Bluetooth, Dual Headphone Amp and much, much more, it’s basically Thanos’ gauntlet with all of the infinity stones in it. However, not everyone needs all this power all the time; sometimes just one or two infinity stones will do.

This is why we made the STEREO HEADPHONE AMP - a simple, compact and great-sounding dual headphone amplifier with AUX in, Bluetooth, pass-thru as well as Stereo Ins and Outs. Meaning you can practice, explore and create in full ear-gasmic stereo. This new little box in KMA’s Utility line will add high-quality headphone monitoring to any rig, wherever and whenever you want it.

Taking those pristine and powerful dual headphone output stages as well as the flexible AUX features from ENDGAME, we have created what we believe to be the definitive, yet still affordable, pedal stereo headphone amp. You can use it as a standalone clean device or you can place it after your amp-sim of choice. Maybe you want a simple way to incorporate backing tracks into your setup? Well, you can do that with the AUX in and Bluetooth features. For example, this could allow you to trigger samples and/or full tracks via your phone or computer. In addition, it’s full Stereo In and full Stereo Out, so you can incorporate your divine stereo effects as well and output it to a stereo interface, mixer or PA. 

With the large Phones Control, it is one knob to rule them all! This controls the master output level for the headphone amp, allowing you to find the perfect volume to suit your needs, and since it’s got some proper size to it, you can actually adjust it with your feet on the fly, if required.

The INPUT LEVEL knob allows you to tweak the input gain to match whatever you have running into the device, be it an instrument, amp-sim or a full signal chain full of effects. While the in-built CLIP LED delivers visual feedback and will blink red if you’ve set the input a bit too hot. You can also run it hot on purpose and send the pre-amp into saturation. It’s actually very musical and has a similar vibe to a blown-out or pushed channel strip on a mixing console. So even though it’s just a small, simple control, don’t be shy to experiment with it a bit.

Placed directly before the Main Outputs, the AUX Input is a super solution for feeding a backing track or any other stereo signal into the outputs, making the STEREO HEADPHONE AMP perfect for many purposes, including practising. Whether streaming via the built-in Bluetooth or connecting via the mini Stereo analogue 3.5 mm jack, the resulting audio signal will be present via either of the two Headphone Outputs and the Main Outputs. Plus, the MIX control allows you to blend anywhere between the core input signal and the AUX Input 

Don’t want the Aux Input to be present on the Main Outputs though? No problem, just press the Output Mode push button from FULL to THRU in order to remove the AUX path from the main outputs easily, effectively turning the STEREO HEADPHONE AMP into a strong, clean, buffered stereo out for your rig.

If you’re anything like us, then you probably already have a pretty decent pedal collection. So of course, we had to make our very own headphone amp, Full Stereo, to accommodate everything from direct and dirt-simple to stereophonic, surreal soundscapes. But what if you want to use it in Mono? No problem. How about Mono In and Stereo Out? A cinch! STEREO HEADPHONE AMP automatically detects what you have connected up and will sum the unused path to the centre. Even if it is in Mono - Mono mode, the Aux input will also still be in Stereo via your headphones, so practice away without losing your head!

Last, but by no means least, we added another trick up the STEREO HEADPHONE AMP’s sleeve for live musicians. If, like many performers today, you use IEMs, you may want more of your own level or have an easy and simple way to blend your own monitoring levels. Many musicians can experience a slight delay between their own signal and what comes back from the monitor mix, depending on the type of connections used and this is even more prevalent with many digital consoles. In addition, if there are not enough aux sends on your rig, sometimes you may not be able to hear yourself in stereo either. So, by using the analogue AUX input for your monitor mix in and the STEREO HEADPHONE AMP’s headphone out to your wired IEMs (or connected to your own IEMs wireless set-up) you will have more direct control over your own levels. In this case, though, just set the Output Mode push button from FULL to THRU to not pass the Aux input section to the Main Outputs - no more arguing with the engineer for “more me” - you have your own control!

Phew, even though we’ve not yet mentioned how cool it is that the KMA Bear’s eye lights up, it still seems so much more than the “Bear Necessities” of what might normally be considered a run-of-the-mill utility device. Come on in to finally sink your own claws into true headphone monitoring for the modern musician!

• Exceptional and Powerful Headphone Amp
• Hear the end of your pedalboard
• Dual Headphone Outputs, with large level control
• Aux Input - Bluetooth Audio or 3.5 mm Stereo Analog
• Aux/Main Mix/Blend Control
• Premium Analog and high-headroom audio, with high-impedance input circuitry
• Flexible internal signal routing - full Mix or Buffered Thru Outputs
• Auto Detect TS/TRS 6.35 mm Inputs and Outputs - Stereo or Mono
• Made in Berlin, Germany

•  Powered by 9 V DC PSU  (centre -, 2.1 mm, <250 mA current draw at max load, not included)