NEUMI BS5 Passive Bookshelf Speakers, 5-Inch Woofer, 1-Inch Tweeter, Dark Wood, 1 Pair

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I didn’t have a chance to run Dirac Live so I can’t speak to what the sound would be post room correction. Max SPL for 20Hz to 20kHz is approximately 82dB @ 1 meter. The compression threshold was exceeded above this SPL. The grille on case results in an increase in comb filtering (higher amplitude peaks/dips). Leave the grille off.

Below is the on-axis response comparison of the BS5P and the previous passive BS5 I tested in June 2020. You can see the updated BS5P has a definite “V-curve” response to it, putting more emphasis on the midbass and high frequencies. These are just some extra sets of measurements I completed. Some, I didn’t process through my MATLAB scripts so they’re kind of raw. But I know some would like to see them so here you go. So, per Neumi’s direction I listened to the speakers both on-axis (0°) and off-axis (≤30°) horizontally. I found the best angle to be directly on-axis. Otherwise, the treble was too subdued. When it came time to measure the speaker, I verified that 0° gave the most linear response and conducted the rest of my analysis with the reference axis being at 0° horizontally and between the mid/tweeter vertically.You may notice that I am more descriptive of frequencies than sounds. Many reviewers will quantify their evaluation discussing how a tone sounded or an instrument sounded. My history has always been in relating the sounds to frequencies so I can understand where I need to EQ. So, I’m no good at telling you a cello didn’t sound like it should with a certain fellow of a certain weight playing it. I just go off relative sounds, basically evaluating performance by “How does this frequency sound compared to another”. But I use this method along with this Interactive Frequency Chart and it works out in the end. However, based on a poll I conducted, most people’s in-room listening distance is between 3 to 4 meters from their speakers at a volume of about 85dB to 90dB. Few people realize just how loud 90dB is. I’ve often found people tend to overestimate their listening levels by a fair bit. But, for the sake of determining how these speakers perform at the higher end of music listening, let’s assume the following: 1) you are in your room and about 4 meters (~ 13 feet) from the speakers and 2) you listen to these speakers at about 90dB at the listening position. The pair of speakers causes a 3dB increase, the room typically adds 6dB, but the change in distance from 1 meter to 4 meters results in a 12dB drop. This equals a total of +3dB from single speaker anechoic 1 meter response to in-room speaker pair at 4 meters. Therefore, in this scenario, you will need to look at the 93dB (7.62vRMS) measurements for THD and Compression. The On-axis Frequency Response (0°) is the universal starting point and in many situations it is a fair representation of the first sound to arrive at a listener’s ears.

Subjective listening was mainly in the nearfield to midfield, between 1 to 2 meters. Subjective listening was conducted at 80-95dB at these distances. Higher volumes were done simply to test the output capability in case one wants to try to sit further away.All data collected using Klippel’s Near-Field Scanner. The Near-Field-Scanner 3D (NFS) offers a fully automated acoustic measurement of direct sound radiated from the source under test. The radiated sound is determined in any desired distance and angle in the 3D space outside the scanning surface. Directivity, sound power, SPL response and many more key figures are obtained for any kind of loudspeaker and audio system in near field applications (e.g. studio monitors, mobile devices) as well as far field applications (e.g. professional audio systems). Utilizing a minimum of measurement points, a comprehensive data set is generated containing the loudspeaker’s high resolution, free field sound radiation in the near and far field. For a detailed explanation of how the NFS works and the science behind it, please watch the below discussion with designer Christian Bellmann: I always listen to speakers before I measure them. This ensures I am not swayed by the measurements before I listen. Listening done on-axis but I also turned the speakers to face out into the room as well. I found on-axis to provide the best overall response. Listening volume between 80-95dB at 4m.

The compression effects shown in the image below are a visual way of seeing just what happens as the volume is increased. This one is straight-forward. Take the legend’s SPL value and add or subtract the data from the graphic. This tells you if you’re losing or gaining output (yes, you can gain output from compression; as un-intuitive as that seems). Mostly, the compression results in a loss due to temperature increase in the voice coil of the drive unit. Let’s look at a specific example. Take the 90dB at 4 meters target listening volume provided above. Again, you need 93dB’s (7.62vRMS) data. At that volume, the highest amount of compression measured is about 1dB at 40Hz and about 0.25dB at 50Hz, decreasing until about 200Hz. At some points the speaker suffered >2dB compression at 40Hz with 14vRMS. Overall, the compression results tell you what common sense would tell you: don’t try to use this speaker in place of a subwoofer at anything other than lower volumes. Otherwise, at louder listening volumes you lose over 1dB of output. And it is audibly present as a very grainy and “limited” sound; there are no dynamics at this output and that’s exactly what I heard in my listening tests when I pushed the speaker to uncomfortable levels. The response linearity is all over the place thanks to the "V-curve" shape and the port resonances at ~800Hz and ~1.8kHz. These resonances were also present in the passive version so weren't necessarily unexpected. However, the V-curve response makes the response of this speaker much further from ideal.

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The blue shaded area represents the ±3dB response window from my calculated mean SPL value. As you can see in the blue window above, the Neumi BS5 has a ±3dB response from 64Hz - 20kHz but only if you ignore the dip in response around 800Hz. Neumi claims a ±3dB window of 50Hz - 20kHz (typical in-room). I don’t believe their spec is a reach but obviously the notch at ~800Hz throws things off. Unfortunately, this notch is pervasive and is brought on by the port, as far as I can tell (more discussion in the Near-Field measurements portion further down). A tighter window of linearity is provided in gray as ±1.5dB from the mean SPL and this speaker does a decent job of trying to stay within that range but the port noise at 800Hz and ~1600Hz make things fall out of that window fast. The treble above 8kHz also begins dipping/peaking enough to keep it out of the tighter window. The area between 300Hz to 700Hz (just before the 800Hz dip) is elevated slightly. This area also lines up with the increased THD levels I discussed earlier. This could be coincidence. But I believe they are related. Maybe the port is having more of an effect in this region than it needs to? This test will consist of the following four (4) SPINORAMA cases and then I’ll provide more in-depth results of the fourth option. Read the titles of the graphics to know what case you’re looking at. All, of course, have the corrected tweeter polarity. Based on my results above, it is obvious the output is limited significantly somewhere above the 96dB @ 1m output level. I haven’t confirmed with Neumi if this is a built-in limiter, though, I assume it is. Port resonance is very, very strong and clearly contributes to the on-axis response dips at ~800Hz and ~1600Hz.

As stated in the Foreword, this written review is purposely a cliff’s notes version. For more details about the performance (objectively and subjectively) please watch the YouTube video. DSP suggestions I also turned the speakers to be about 10 to 30° off-axis to see if I could get rid of the harsh treble. That didn’t help much at all and when you view the data you can see the off-axis response has low directivity around 4kHz (meaning, the sound is more omnidirectional at this frequency) which indicates the bright 4kHz region would be noticeable through a wider region of angles. I believe this explains the “biting” noise I was hearing as well. I noted the price in the title because I've gotten a lot of people asking about budget speakers so, here you go. The fourth option, above, provides the best overall response and one that is much more pleasing to my ears. Therefore, the majority of my review is based on this particular option (updated EQ and ports stuffed).However, these “collapsed” representations of the sound field are not very intuitively viewed. At least not to me. So, I came up with a different way to view the speaker’s horizontal and vertical sound field by providing it across a 360° range in a globe plot below. I have provided both an absolute SPL version as well as a normalized version of both the horizontal and vertical sound fields. Very heightened high frequency content, which is fatiguing when listening long-term, especially at higher volumes. Multitone distortion testing. The dashed blue line represents the -20dB (10% distortion) threshold for failure. The dashed red line is for reference and shows the 1% distortion mark (but has no bearing on pass/fail). The green line shows the final measurement where either distortion and/or compression failed. The voltage just before this is used to help determine the maximum SPL. I simply forgot this test but if you are interested, please see previous test’s results. Long Term Compression Tests Despite the manufacturer stating “optimized for a smooth frequency response while limiting distortion at high sound levels”, this is not a reference speaker. Furthermore, in my humble opinion, the BS5P is unfortunately a step-down in fidelity from the Neumi BS5 (passive speaker) I reviewed in the past.