This is a review and detailed measurements of the Edifier MR4 powered "studio" monitor (speaker). It was sent to me by the company and costs US $130.
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This is a very small speaker. It looks larger in the marketing material. You can easily carry it with one hand. I was impressed by the use of waveguide and help from Klippel Germany on the measurement side. Unlike typical "multimedia/PC" speakers, you have balanced inputs:
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That should help reduce possibility of ground loops/hum. Connection to the other speaker is through one pair of wires which means the crossover is passive and there is one amplifier per channel.
There are notches for LF and HF shelving. I set the in their detent which on the HF side, was to the left of center. I made the NFS measurements below using that, and "monitor mode." If you click the power button twice, you get into music mode. I made a few measurements to quantify the difference:
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I expected the Music mode to have much more exaggerated lows and highs but instead, it seems to have a more even on-axis response. Getting to the same place with the HF control requires boosting it to the 2 dB marker.
Measurements that you are about to see were performed using the
Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise.
Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.
Measurements are compliant with latest speaker research into what can predict the speaker preference and is standardized in CEA/CTA-2034 ANSI specifications. Likewise listening tests are performed per research that shows mono listening is much more revealing of differences between speakers than stereo or multichannel.
Reference axis was the center of the tweeter (aligned by eye). It is getting colder with the measurement room temp at 14 degrees C. Accuracy is better than 1% for almost entire audio spectrum indicating a well designed speaker.
Edifier MR4 EVO Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker is and how it can be used in a room. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:
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As you could tell from the (in-room) preview in the intro, there is a dip in the lower treble frequencies. And we have some resonances/peaking centered around 600 Hz. Outside of this though, directivity control is good due to use of that waveguide. More on this later.
Near-field response shows uneven treble response so maybe this is why we are deficient close to the crossover frequency:
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Unfortunately the early window reflections exaggerate this:
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Resulting in a shelved predicted in-room response:
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I am impressed by the amount of bass this little speaker is producing. It is flat down to 70 Hz! The broad deviations are very audible but rather easy to correct with EQ as you see later.
At 86 dBSPL playback level distortion was good but at 96 dB, speaker fell apart making all kinds of squealing sounds. I played with volume vs input level and got some improvements but still horrid at 96. So I reduced level to 90 dBSPL where I could still hear odd noises:
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The waveguide pays dividends in directivity and beamwidth in the horizontal axis. It is unusually good for speakers in this price range and even higher:
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And the wide width means that you can move left and right at your workstation without much change in tonality.
Vertically is not as good and this is typical of 2-way, non-coaxial designs:
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For fans of timing tests, here is the waterfall:
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Impulse response:
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And for the first time, step response:
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Edifier MR4 Listening Tests and Equalization
First impression defies the look of the measurements: the sound is warm and reasonably nice sounding. That extended bass response really helps here. I took out the EQ tool and made some quick adjustements:
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Taking down the resonances around 615 Hz took out some of the stuffiness of the upper bass and provided more clarity. The filter next to it is there to truncate its response as there is a dip on the right that is not on the left. I then boosted the deficient region around 4000 Hz. I went easy there as I don't like bright sounding speakers.
Note that you can get part of the way there by using the rear HF control and boosting a few dB (per listening tests and measurements). Once there, you do have good sound without having to deploy EQ.
There is a cost to the extended bass: you can't get too loud. Try to do so and at first there is clicking/static is barely noticeable. Turn up the volume more and it gets quite a bit worse. I say you can only get to medium level with one speaker playing. With two speakers it should be better (I did not test). This is with content that has normal amount of lower bass. With techno/drum loop content such as Peace of Mind track you see in the EQ panel, it could get quite a bit louder with no audible distortion.
Conclusions
You are paying so little for a speaker that attempts to follow the path of much more expensive monitors with proper waveguide and balanced inputs. It takes over them with inclusion of volume control, RCA inputs, etc. Bass response is flat and impressive for such a small/light speaker. I wish it did not have the dip in lower treble though. Not sure why that is there if they did measure the speaker.
If you need an ultra cheap, active speaker and can use a bit of EQ, the Edifier MR4 makes a decent option. Just keep your expectations low as far as playback level.