ALO Rx Prescription Headphone Amp - Black

Designed from scratch, the ALO Rx is utilizing dual power sources: two 3,7 volt rechargeable Li-ion batteries which supplies tons of power for headphones of all flavors, from the ultra-sensitive IEM more power-hungry circum-aural headphones.

The Rx is a fresh approach to portable headphone amp design. This amp was designed from the ground up to provide the best sounding, most convenient product on the market.

First off is the dual lithium-ion battery charging circuit; this is one of the first products in the world to use this circuit. Most portable audio products only provide a constant current source to charge the batteries. At best, this approach limits the life of the batteries, it is very possible that inadequate charging circuitry can be hazardous. The Rx's circuit is much more complex, in that it constantly monitors the batteries voltage and current capability. The Rx charging circuit has intelligent charging that determines the optimal current and voltage to feed the batteries that will best charge and preserve the life of the batteries.With the solid foundation of a high- performance, safe, and convenient power supply, next is the preamp / volume control. The Rx utilizes unique digitally controlled dual stepped attenuator circuit. The Rx amp is the first portable amp to use this circuit. Other products feature "similar" products that were designed for microprocessor A/D circuits, not audio - resulting in inferior audio quality and too many audio steps in the wrong places. The Rx volume control starts at a reasonable level which does not leave the user to wonder if the amp is not on or faulty.

All of this circuitry is fitted into a custom-designed aluminum extrusion that is modeled and optimized using 3-D CAD software.

The amp’s dimensions is a super small 2.5 * 0.5 * 4.2 inches of extruded aluminium.


Further Details

• High output power - a minimum of 5.25V peak to peak and over 200mA of output current, so can easily drive any headphones.
• The ALO Audio Rx has a real bi-polar power supply not a rail splitter…
• Long-lasting, rechargeable battery - The ALO Rx contains dual lithium-ion battery which will power the amp for more than 17 - 30 hours at typical listening levels. It recharges in about 2 - 4 hours from an external wall-wart charger. You can also operate it while plugged in to keep the battery topped off. Uses a proprietary DEDICATED battery supervising / charging IC. Internal gain switch, tested with high end IEMs and sounds amazing with both full size headphones and IEMs

• Frequency response: ±1dB; 10Hz - 20kHz ±0.1dB @ 1V out
• Maximum output: 7.45V Peak to Peak
• Output source impedance: Less than 1Ω
• THD+N: 0.004% @ 1V RMS out into 24Ω
• Broadband noise: <10μV RMS, unweighted, integrated over 20Hz - 20kHz
• Output DC offset: <3mV
• Input impedance: 40kΩ
• Maximum input level: 5V RMS
• Channel tracking (gain difference between channels, all volume steps): <±0.2dB
• Gain: 1.5X /6X ---5V (switch-selectable), ±<0.5dB
• Dimensions: 4.2″ long x 2.5″ thick x 5″ wide


"Bravo on the Rx amp! I received mine on Monday and quickly gave it a test with my iPhone, the Cryo LOD and my Edition 8’s. The combination was stunning and the Rx really brought out the best of the Edition 8. Bass response has always been a strength of the Ed8, but I have never heard it tighter or better defined. Midrange, which I had previously found a bit recessed with the Ed8, seemed much more prominent when amped by the Rx. Couple that with a dead silent noise floor and a very precise digital volume control and I am more than pleased. The icing on the cake is the build quality and the fact that it looks almost custom-made to pair with an iPhone of iPod Touch." -Robert

Straight out of the box, the RX amp sounds amazing.....Highs and Lows were smooth and controlled but still alive enough to keep me glued to my music. the mids were surprisingly apparent. Im listening through D7000s so yeah, what i heard was more forward mids. the recessed mid problem was gone from my D7000s. When on pause all i could hear was total silence. Vocals were very alive and smooth. Sibilance was barely noticeable on some songs but i believe that had more to do with the file itself rather than amp and headphones. I used to need my FiiO E5 in line as a bass boost with the Hornet but I have no need for it with the Rx. Not saying that the RX is a bass monster but it's good enough for me by itself.-Samuel

"How's it sound? Not brash, strident, lean, thin, nervous, flat. Instead, it's unbelievably gutsy and potent 'all over'. .... -Srajan Ebaen Editor 6moons.com


Headfonia.com Review : ALO RX Amp I was immediately impressed with the wide soundstage presentation of the ALO Rx. Most of the time I find that the soundstage from IEMs are not big enough, but with the ALO Rx, IEMs find the boost they need. As a matter of fact, I can nominate the ALO Rx for the portable amplifier with the biggest soundstage. Editor Headfonia.com Michael Ting"


User Review Head-fi.org : ALO RX Amp (Quite Possibly the Perfect JH13 Amp)

Ipod cables and headphones sold separately.