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Alto Professional UBER FX Portable PA

No power? No problem!


by Phil O'Keefe



I'm sure you can think of situations and locations where you'd like to have a small, portable PA system, but where AC power to run it is not available. Maybe it's so you can do announcements and play background music at a family or company picnic, or for public address use at an outdoor business-related meeting or function, such as a groundbreaking ceremony on a new construction project. Maybe you're going to the river or lake, and would like to do a little jamming on the boat, or maybe you're going camping or to the beach and would like something to use there. And of course, there's always busking and other small audience public performances. But while there are some guitar amps out there that can be battery powered, there are not a lot of PA systems with that capability. Alto Professional offers a few, and their latest model - the UBER FX under review here - is their most powerful and fully-featured one to date. Let's take a look at what it has to offer.





What You Need To Know

  • The Alto Professional UBER FX is a 100W (peak power), four-channel portable PA that can be powered from an AC outlet, or with its internal 7 Ah SLA (sealed, lead acid - smaller, but otherwise similar to what is used in your car) battery.
  • The UBER FX is surprisingly lightweight and compact, weighing 24.7 pounds and measuring 18.1" H x 18.3" W x 11" D.
  • While UBER FX is light in weight, it doesn't appear that it was done at the expense of durability. The bass-ported cabinet is made from heavy duty plastic with lots of edge and corner reinforcements built into it. It looks reasonably rugged and tough, with a steel grille protecting the UBER FX's 8" woofer and 3" tweeter, while heavy-duty handles on either side of the unit make it easy to lift.




  • A combination IEC power connector / fuse housing unit is located on the back. The UBER FX can be used with 100-240 V AC at 50 or 60 Hz, making it compatible with power outlets world-wide - you just need the proper IEC cable with the right plug at the end of it, and you're good to go. An IEC power cable with a US-compatible plug was included with the review unit. 
  • You can't overcharge the built-in battery (the built-in charger shuts off automatically once the battery is fully charged), so it's safe to leave it plugged in whenever AC power is available. 





  • There is a telescoping handle (similar to what you might find on a modern suitcase) that retracts into the unit itself, as well as a pair of wheels mounted on the bottom at the rear of the cabinet, making it even easier to move around - just unlatch and pull out the handle and tilt it back a bit and roll it to wherever you want to take it, just as if it were a piece of luggage.
  • Input channels 1 and 2 are the two main inputs, and they are identical in terms of features. Each has a combo XLR / 1/4" mic / line input jack, along with a small slider switch to select between them. Channels 1 and 2 each has its own separate Volume control.



  • Each of the two main input channels also has a two-band EQ. Each band can boost or cut up to 12 dB, with the Bass EQ centered at 100 Hz, while the Treble is centered at 10 kHz. 
  • There's a good reason for the "FX" in the product name. Each of the two main channels also has a dedicated Effects Level knob, which feeds into the UBER FX's built-in Alesis digital effects processor.



  • The built-in Alesis effects engine offers 15 different effects algorithms, and the active algorithm is selected with the Effects Selector knob. A bypass option provides a 16th position on the selection knob for those times when you want a completely dry signal with no effects.
  • The available options include two Hall, three Room and three Plate reverbs, along with modulation effects like Chorus, Flange and even a Rotary Speaker simulator. There are also two Delay effects, and even two Chorus / Room combinations. None can be edited - the effects are preset-only. 
  • The other two channels of the UBER FX are more limited in scope. Channel 3 is a Bluetooth connection, so you can feed signals into the UBER FX wirelessly. The Alto Professional UBER FX supports NFC (Near-Field Communication), allowing devices with NFC to connect without having to use the typical Bluetooth selection menus to connect - just tap the device on the NFC icon on the Uber FX's top panel and you're all set.
  • Channel 4 is an Aux input, with a stereo 1/8" TRS jack. This is perfect for connecting CD players, tablets and smart phones directly to the UBER FX, although you'll need to provide your own 1/8" cable.
  • A single shared Volume control sets the level for both Channels 3 and 4.
  • A Master Volume knob, power switch and battery power LED meter round out the front panel controls. A single 1/4" Line Output jack is also provided; it is post-master volume control, so its level is determined by how high the Master Volume knob is set.
  • There's a 1A USB charging port on the front, so you can even recharge your phone or tablet directly from the Alto Professional UBER FX. This port works whether you're powering the UBER FX from an AC outlet or using the internal battery.
  • The frequency response of the Alto Professional UBER FX is 60 Hz - 17 kHz, +/- 3 dB. It sounds much bigger than it appears, and is surprisingly full sounding and punchy for such a small enclosure.




  • My initial charging time to reach a full charge on the internal battery took longer than the 12 hours that the UBER FX manual suggests it will take. In fact, it took nearly twice that long, in spite of the meter saying the unit had about 50% charge in it when I received it. However, subsequent recharging did take substantially less time, and was easily accomplished overnight. Just be aware that the first charge might take longer than you expect.
  • Likewise, take the "up to 45 hours" of battery life before needing a recharge claim with a grain of salt too. You might indeed get that much, but as the manual points out, battery life will depend on how hard you're running the UBER FX, as well as how old the internal battery is, and even how hot or cold it is where you're using it. I ran the test unit as hard and loud as I could (short of obvious audible distortion) and it gave me over eight and a half hours of full-volume use before dying, and it did so while also simultaneously recharging my iPad, which had less than 50% on its internal battery charge when I plugged it into the UBER FX. If you're running it hard, you can expect much less than 45 hours of play time from the UBER FX.  I wouldn't recommend running it until it dies, since that can potentially be detrimental to the onboard battery if it's done too often.
  • There's no pole mount built into the bottom of the cabinet. While there really isn't room for one, it would have been nice to have. Getting the UBER FX up on a chair or table to elevate it is definitely beneficial in terms of overall performance and "reach" - it's more effective if you can aim it at your audience and place it as close to ear level as you can, instead of leaving it sitting on the ground and aiming it at their feet.
  • As the manual points out (and so does a notice on the UBER FX's front panel), you need to pay attention to regular maintenance to keep the onboard battery healthy. The UBER FX should not be stored in freezing conditions, and it needs to be recharged every couple of months, even when you're not using it.




There aren't a lot of options available in self-powered PA systems, but the Alto Professional UBER FX is definitely a good one, as long as the number of inputs and the output power meet your needs. It's important to have fairly reasonable expectations here. This isn't going to compete with larger PA systems. I was able to generate ~95 dB SPL from the UBER FX in a fairly large room, with it regularly hitting 100 dB SPL(A) peaks, but it's not going to generate 120 dB SPL under any circumstances, and if that's what you need, you really should consider a much larger mains-powered PA system.

As with just about any piece of gear, the UBER FX is not perfect, and I can think of a few things I've like to see added to it, such as a pole mount and a switch to a higher Amp-Hour lithium battery (lithium iron phosphate would be ideal), which would not only improve the already ample playback time, but would make regular battery recharging when the unit isn't being regularly used less crucial, since the more modern batteries don't suffer from memory effect like SLA batteries do. However, this would no doubt add significantly to the price of the unit. I wasn't able to test the NFC pairing since none of my devices support it, but connecting an iPhone with regular Bluetooth went off without a hitch. Range is said to be up to 100 feet, but I doubt most people will need even a third of that, and I was easily able to maintain connection with an iPhone and the UBER FX indoors, through multiple walls, at that distance. I was surprised to discover that Channel 3's Bluetooth and Channel 4's stereo aux inputs can both be used simultaneously. While they do share a single Volume control, the relative volumes of the two connected devices can be adjusted at the sources - assuming they have output volume controls.

There's a lot to be said for this nifty little all-in-one compact PA. I really like the light weight and the easy portability. The built-in telescoping handle and wheels make it incredibly easy to take with you. I was also really impressed with just how much sound you can get out of a small battery-powered PA - and it's actually pretty darned decent sounding too, with more low frequency reach than I was expecting. While you can't edit things such as delay times or regeneration, the quality of the reverbs and effects are certainly quite decent, and their inclusion is a very useful addition to this product, making it an even more capable all-in-one portable PA solution for musicians. Part portable wireless Bluetooth speaker, part small PA system, and fully portable, with the ability to function whether or not there is AC available to power it or not, the Alto Professional is a nearly ideal mobile companion for solo or duo acts. Buskers are going to love this thing too. If you need PA power on the go, it's well worth checking out the UBER FX.   -HC-



Want to discuss the Alto Professional UBER FX or have questions or comments about this review? Then head over to this thread in the Live Sound forum right here on Harmony Central and join the discussion!




Alto Professional UBER FX portable PA system ($249.95 MSRP)

Alto Professional's product web page







Phil O'Keefe is a multi-instrumentalist, recording engineer / producer and the Senior Editor of Harmony Central. He has engineered, produced and performed on countless recording sessions in a diverse range of styles, with artists such as Alien Ant Farm, Jules Day, Voodoo Glow Skulls, John McGill, Michael Knott and Alexa's Wish. He is a former featured monthly columnist for EQ magazine, and his articles and product reviews have also appeared in Keyboard, Electronic Musician and Guitar Player magazines.  

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