Saturday, May 11, 2019

Emotiva BasX A-500 5 Channel Home Theater Amp Review

We’ve come a long way since the beginning of Dolby with Dolby Stereo. The sound keeps getting better, not just in the number of channels, but also the quality of the sound as well. We now have easy access to 11 channels for full surround sound envelopment with Dolby Atmos and DTS:X. And modern surround sound receivers also allow use of discrete separate amps for better sound. So whether you want to improve the sound of your 5.1 of 7.1 surround sound, or you want to upgrade to the latest 7.1.4 of Dolby Atmos or DTS:X, you will probably need a separate amp. Enter the Emotiva BasX A-500.

Emotiva is an audio product manufacturer that focuses on the budget minded audiophile. If you consider yourself an audiophile and are looking for a high quality product that gives a huge bang for your buck, Emotiva is who you are looking for. And a great amp of theirs from their budget BasX line is the BasX A-500. If you want to improve the sound of your main 5.1 channels, it’s a perfect fit for that. But if you want to make the jump to Dolby Atmos or DTS:X and add 4 ceiling height channel speakers, the Emotiva BasX A-500 will work great for that as well.

Features and specs:

Circuit Topology

The BasX A-500 is a five channel power amplifier. The BasX A-500 combines classical audiophile amplifier architecture, based on a heavy-duty linear power supply, and a carefully designed high current short signal path Class A/B output stage, with advanced microprocessor-controlled monitoring and protection circuitry, to deliver superb sound quality at a truly reasonable price.

Audio Specifications

Power Output (two channels driven):

110 watts RMS per channel; 20 Hz – 20 kHz; THD < 0.1%; into 8 Ohms.

190 watts RMS per channel; 1 kHz; THD < 1%; into 4 Ohms.

Power Output (all channels driven):

80 watts RMS per channel; 20 Hz – 20 kHz; THD < 0.1%; into 8 Ohms.

Power Bandwidth (at rated power; 8 Ohm load): 20 Hz to 20 kHz (+ / – 0.07 dB)

Broad Band Frequency Response: 5 Hz to 80 kHz +0/-1.8 dB

THD + noise: < 0.02% (A-weighted); ref rated power

Signal to Noise Ratio (8 Ohm load):

> 120 dB; ref rated power; (A-weighted).

> 100 dB; ref 1 watt; (A-weighted).

Minimum Recommended Load Impedance (per channel): 4 Ohms

(which equals one 4 Ohm load or two paralleled 8 Ohm loads).

Damping Factor (8 Ohm load): > 500.

Input Sensitivity (for rated power; 8 Ohm load): 1.2 V.

Gain: 29 dB.

Input Impedance: 27 kOhms.

Input And Output Connections

Input Connections: Unbalanced (RCA); one each per channel.

Speaker Output Connections: Audiophile grade 5-way binding posts.


Trigger Input: 5 – 12 V (AC or DC); <10 current="" font="" input="" ma="" required.="">

Trigger Output: 12 VDC; can drive any load up to 120 mA.

Power Requirements

115 VAC or 230 VAC @ 50 / 60 Hz (automatically detected).

Front Panel Controls and Indicators

Standby: push button (halo ring changes color to indicate Standby or On).

Status LEDs: one per channel; blue.

Status LEDs change to red to indicate a fault condition.

Rear Panel Controls

AC Power switch: rocker switch (switches AC main power).

Status LEDs switch: disables front panel Status LEDs.


The BasX A-500 is protected against excessive operating temperature, shorted speaker connections, ground faults, and other common fault conditions.



17” wide x 4” high x 15-1/2” deep (not including connectors).

21-1/2” wide x 8” high x 21” deep (boxed).


26.5 lbs (unboxed)

35 lbs (boxed)

The Emotiva BasX A-500 came double boxed in a standard brown cardboard box. Opening the box revealed a well protected amp, held securely in place by custom molded Styrofoam, and wrapped in a black cloth bag. Pulling out and unwrapping the amp revealed a very well made product. Materials used in the construction were almost all metal, with a very high quality brushed black aluminum face plate. Quality of materials used was also excellent, as was fit and finish. The Emotive BasX is a very well made product and it shows. Taking off the cover plate showed high quality internal components, with tight connections. Connections on the back were also very good. I was amazed at the quality for only $499, and starting to get very excited to hear how it sounds. Also included in the box was the power cord, remote turn on cable, owner’s manual, and a couple spare fuses. 

 Setting up the amp in my rack was very simple. It was just a matter of connection the RCA line outs on the receiver to the line ins on the back of the amp. Then connecting the remote out of the receiver to the remote in on the amp, and then plugging it in. Having a Dolby Atmos or DTS:X 7.1.4 system in our reference room, we will be able to test the Emotiva BasX A-500 for both scenarios.

Our reference receiver is the Onkyo TX-RZ920, which has an internal THX amp rated at 135 watts, 2 channels driven at 1 kHz. The Emotiva BasX A-500 is rated at 110 watts a channel, but is rated at 20-20000 Hz. The power output should be fairly close for both the Onkyo and Emotiva, even though the rated output is a little different. This should be a fairly good apples to apples comparison. That way we can tell how the Emotiva BasX A-500 compares to an internal receiver amp. And then we’ll test how well it does as an upgrade add-on for Dolby Atmos or DTS:X. Now that it’s all connected, let’s hear how it sounds.

I started off with measurements from my sound meter, and measured during a few clips of a couple of my favorite movies: RED and Ready Player One. Reference gear used was an Onkyo TX-RZ920 THX Receiver, Oppo Digital BDP-103D transport, NHT Classic Three’s and NHT Classic Three C, in a 5.1 system and SVS 16-46 PC Plus as the subwoofer. I first measured using just the internal amp at a set volume level on the receiver. I took measurement readings for peak volume during a few clips for each movie. After I was done measuring the several clips in both movies, I hooked up the Emotiva BasX A-500. I went through the same clips of each movie, listening to each clip a few times and noting the peak volume of each clip at center listening position. The measurements came out really close, as I expected. Through out all of the clips, there was only a 1db difference in volume at the same output level, and it was the Emotiva amp that had the lower volume output. But that could be due to the slight signal loss going from the receiver to the amp through the RCA’s. But again, the difference is minimal, barely noticeable if you are listening for it and doing an AB test the way I was. Now let’s see how they actually sound. 

I was impressed with the sound of the internal amp of the Onkyo TX-RZ920. In fairly recent years, Onkyo made the jump to using a digital amp.  While it’s a digital Class D topology, it still has a very good neutral sound. For those who don’t want more, it’s a good amp. And is even THX certified.

If you want to get the best performance out of your home theater, getting a dedicated amp is the way to go. The Emotive BasX A-500 is a great economical way to do it! With an MSRP of only $499, it’s a steal! As stated previously, the output in volume is just a hair under the output of the internal amp at the same volume level of the receiver. But that’s just part of the story. There is a lot more head room with the Emotiva.

Listening to the Emotiva BasX A-500, I heard the same neutral sound as the internal amp, but there was also a lot more. Music had more clarity and resolution. The midbass was fuller with more punch. Dynamics in movies was also greater. The difference was not huge, but it was there and noticeable. And in cranking up the volume to much louder than I listen to, it was still really clean, with crisp highs, smooth mids, very articulate vocals, and tight punchy midbass.  Transparency level from the amp was also very good!  And not only that, but it sounded just really full, with plenty of reserves still on tap.

It’s kind of like the analogy I like to use with engines, and horse power and torque. You can get a big horsepower engine without a lot of torque. And while it’ll have power in the horsepower, with a lack of torque it’s lacking muscle behind it. So while the internal amp sounds good and will play loud, it doesn’t have the reserves or muscle behind it like you get with and engine that has a lot of torque. You won’t have the same full sound or the perceived headroom behind it so it won’t sound a tad thin. You can definitely tell using the Emotiva as dedicated amp gives you a lot of brawn on tap.

The Emotiva BasX is an outstanding dedicated theater room Amp. If you’re happy with the performance of your internal amp, but want to make the jump to Dolby Atmos, or DTS:X, the Emotiva BasX A-500 is a great add-on amp to power the 4 height channels. And given the close output levels as previously discussed, it’s also a great match to the internal amp, when used to power the height channels, as they are both close to the same wattages.

 Using the Emotiva BasX as an add-on amp to power 4 height channel speakers proved to be an excellent fit. Getting it all wired up, and running the calibration software, it was now time to test the amp with Dolby Atmos in 5.1.4. As Darth Vader said to Luke, “Impressive, most impressive.” The Emotiva BasX A-500 made my Revel C263’s really sing! Highs were crisp and clean, mids were very smooth and bass had good extension and punch in the midbass. There was plenty of power on tap for the Revels, and the sound provided with Dolby Atmos was holographic, fully enveloping you in all of the action!

 In the end, the Emotiva BasX A-500 provides a real synergy! It provides an excellent build quality for a product that will provide years of use. But it sounds just as good, giving a performance that is more than the sum of the parts. It’s not perfect, but given its low MSRP of only $499, it’s bang for the buck is off the charts! And it provides a lot of functionality. If you’re looking to up your game in your home theater setup, the Emotiva BasX A-500 should be on your short list. But I do have a word of caution.  If you are using your surround sound receiver to power your mains and get a BasX amp for the height channels, don’t try out the BasX on your mains.  If you do, you may just end up keeping it there and getting another BasX for the height channels! Like a BasX A-700 for the mains and a A-500 for the heights in a 7.1.4 setup. Based on its design, features, quality and performance, the Emotiva BasX A-500 has earned our Editor’s Choice Award. For more info and complete specs, check out their website at
*Sample product provided did not have any influence on the resulting review