superfluid
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This is a sister post to How to Improve a Rivian R1S’s Elevation Sound System With Simple EQ Changes.
TLDR;
Tip: Listen to the new setting for a while using familiar songs at low volume and higher-than-average volume. Your ears/brain may take a bit to get accustomed to the new balance. What should happen is that you hear instruments/sounds more clearly because overtly emphasized frequency ranges aren't drawing attention away from them. Then tweak to taste.
Many folks posted requests in the R1S Elevation thread for measurements and recommendations for a Meridian system. @RivianBowerbird generously offered his R1T Meridian and time to me to make measurements, do listening tests, and recommend some simple EQ improvements. To my ears, the Meridian system sounds noticeably better than the Elevation system out of the box, and the above changes helped it sound even better. I think RivianBowerbird would agree.
A few notes before getting into the details...
While I love audio, I enjoyed most spending an afternoon with a fellow Rivian owner sharing stories about our Rivians, talking sound and audio, and listening to all kinds of music on my home system with a fellow music enthusiast. @RivianBowerbird is an infinitely curious guy who loves understanding the fundamental science behind why things work the way they work. My kind of dude. It was such a pleasure to connect with someone with a shared passion through this community in person.
This post will be much shorter than the R1S Elevation post because I won't repeat explaining my background in audio or the acoustic and psychoacoustic science behind why things sound good or bad. If you're interested in those things or the basic science behind my analysis and recommendations, check out the R1S Elevation thread.
Objectives, Methodology, Tests, and Results
Objectives
Tests
I ran 5 sweeps from 0-20,000 Hz through the Left and Right device inputs. After each sweep, I adjusted EQ based on the results of my measurements and listened to tracks I used to test many different systems. I asked RviainBowerbird to provide his impressions before I gave mine to avoid biasing him. He gave assessments that largely matched my own after each change. Not only did this mean he listened well, but the changes were meaningful.
A sweep is an audio signal sent to the sound system that sweeps across a given frequency range at a uniform volume. The recording microphone picks up what comes out of the speakers and what the room—the cabin, in this case—does to the sound. I forgot to take a picture of the microphone setup in the truck, but I was having too good a time chatting with RivianBowerbird about the process and procedure to remember.
I didn't need to do 18 sweeps like I did when I measured my R1S Elevation because I already had an idea of how the system worked and only needed to confirm it. The EQ’s scale is 10 dB. Each notch represents +/- 1 dB of gain or attenuation, just like the R1S Elevation.
As with the R1S Elevation, I used the first sweep as a reference to see outstanding acoustic issues and set a baseline for the effects of the EQ changes I made. I only changed EQ because I had no other tools at my disposal. With home theater systems, you can change delay and implement different kinds of filters to affect phase and other stuff that doesn’t matter in the Rivian because we can’t change it. The Meridian system offered no EQ adjustments beyond the Elevation.
I learned a few things from taking measurements:
Results, Recommendations, and How to Interpret a Frequency Response Graph
Here is the reference measurement with markup highlighting problem areas.
The graph shows frequency (x-axis) plotted against dB or volume (y-axis). In an ideal world, the graph would show a smooth line from 20 Hz to 20 kHz without big bumps and dips. The green line helps us visualize what that “ideal” frequency response might look like. It’s taken from Harman Audio’s research of people’s preferences. The closer a measurement is to a target curve like this one, the more balanced and clear the system will sound.
The target curve isn’t ruler flat (i.e., does not have a zero slope) because people tend to prefer relatively more bass and relatively attenuated high frequencies. This has to do with the fact that human ears have different sensitivity to different frequencies; namely, we have a much harder time hearing bass frequencies than mid-range frequencies, even when they play at the same volume. This phenomenon is known as the equal-loudness contour. We need a lot more bass to perceive it at the same level as 1 kHz so we tend to prefer boosted bass.
As you can see, the R1T Meridian wasn't egregiously far off from the Harman target curve in most areas. However, it had problems.
The R1T Meridian's main problems were:
How do we address these issues?
Unfortunately, we can only address them coarsely because the Rivian system doesn’t allow us to change the frequencies we boost and cut. We’re stuck with the frequencies they give us. However, the R1T Meridian system was properly designed (outside of the rattling issue, which we'll get to), so it doesn't require a lot of surgical intervention (unlike the R1S Elevation).
After experimenting with several EQ settings, here’s where I landed:
NOTE: RivianBowerbird didn't have the highest-quality tier of TIDAL, so we couldn't test the Meridian system's full resolution. However, I suspect the Meridian system may sound better than what I heard using a higher-quality source.
Comparison of R1T Meridian and R1S Elevation Systems
Now that I've made an objective comparison of the R1T Meridian and R1S Elevation systems, I'm more convinced that the Elevation system was misdesigned. My hypothesis was, and remains, that Rivian engineers swapped out the Meridian speakers for Elevation speakers without modifying the cross-over to suit, creating significant response issues at the standard cross-over range around 1 kHz that the Rivian's EQ cannot fix. (See the sister article for details about that.) The difference above 6 kHz is also explainable by a failure to modify the electronics after swapping the speakers.
However, the results are still inconclusive because other differences between the R1T and R1S, like cabin size and the number of speakers, could explain the performance difference between the Meridian and Elevation systems. The most conclusive test would be comparing an R1S Meridian to an R1S Elevation system.
Anyone in or around Austin willing to get their R1S Meridian measured?
TLDR;
- Flatten your EQ by using the “Default” setting or the reset icon.
- Turn off 3D Surround Sound.
- Use these EQ settings: 63 Hz -3 notches, 125 Hz -3, 1 kHz +3, 2 kHz +3.
- Use Tidal or Spotify, ideally with a high-quality subscription tier. Avoid Bluetooth for music playback.
- Adjust to taste and enjoy better listening.
Tip: Listen to the new setting for a while using familiar songs at low volume and higher-than-average volume. Your ears/brain may take a bit to get accustomed to the new balance. What should happen is that you hear instruments/sounds more clearly because overtly emphasized frequency ranges aren't drawing attention away from them. Then tweak to taste.
Many folks posted requests in the R1S Elevation thread for measurements and recommendations for a Meridian system. @RivianBowerbird generously offered his R1T Meridian and time to me to make measurements, do listening tests, and recommend some simple EQ improvements. To my ears, the Meridian system sounds noticeably better than the Elevation system out of the box, and the above changes helped it sound even better. I think RivianBowerbird would agree.
A few notes before getting into the details...
While I love audio, I enjoyed most spending an afternoon with a fellow Rivian owner sharing stories about our Rivians, talking sound and audio, and listening to all kinds of music on my home system with a fellow music enthusiast. @RivianBowerbird is an infinitely curious guy who loves understanding the fundamental science behind why things work the way they work. My kind of dude. It was such a pleasure to connect with someone with a shared passion through this community in person.
This post will be much shorter than the R1S Elevation post because I won't repeat explaining my background in audio or the acoustic and psychoacoustic science behind why things sound good or bad. If you're interested in those things or the basic science behind my analysis and recommendations, check out the R1S Elevation thread.
Objectives, Methodology, Tests, and Results
Objectives
- Understand the R1T Meridian audio system’s faults.
- Understand the system’s behavior.
- Determine what—if anything—I could do to improve its performance.
- Compare the R1T Meridian system's performance to the R1S Elevation's.
- Flattened the EQ using the Default setting.
- Turned off 3D Surround Sound and Dynamic Sound Adjustment.
- Set Fade and Balance to default.
- Set Soundstage Center to default.
- Turned off climate control to reduce in-cabin noise as much as possible.
- Put a calibrated UMIK-1 microphone roughly where my ears would be in the driver’s seat.
- Connected my MacBook Pro to the Rivian Audio system via Bluetooth. This connection method had meaningful downsides—namely data and resolution loss- but Rivian Support told me they didn’t know of another way to make the vehicle a target audio device. USB didn’t work.
- Set the Rivian’s volume to 16 to give me 75 dB of pink noise, C-weighted, generated by Room EQ Wizard (the industry standard acoustic measurement app). 75 dB is a typical level for performing measurements.
Tests
I ran 5 sweeps from 0-20,000 Hz through the Left and Right device inputs. After each sweep, I adjusted EQ based on the results of my measurements and listened to tracks I used to test many different systems. I asked RviainBowerbird to provide his impressions before I gave mine to avoid biasing him. He gave assessments that largely matched my own after each change. Not only did this mean he listened well, but the changes were meaningful.
A sweep is an audio signal sent to the sound system that sweeps across a given frequency range at a uniform volume. The recording microphone picks up what comes out of the speakers and what the room—the cabin, in this case—does to the sound. I forgot to take a picture of the microphone setup in the truck, but I was having too good a time chatting with RivianBowerbird about the process and procedure to remember.
I didn't need to do 18 sweeps like I did when I measured my R1S Elevation because I already had an idea of how the system worked and only needed to confirm it. The EQ’s scale is 10 dB. Each notch represents +/- 1 dB of gain or attenuation, just like the R1S Elevation.
As with the R1S Elevation, I used the first sweep as a reference to see outstanding acoustic issues and set a baseline for the effects of the EQ changes I made. I only changed EQ because I had no other tools at my disposal. With home theater systems, you can change delay and implement different kinds of filters to affect phase and other stuff that doesn’t matter in the Rivian because we can’t change it. The Meridian system offered no EQ adjustments beyond the Elevation.
I learned a few things from taking measurements:
- The 6"x9" woofer in an enclosure under the passenger side second-row seat rattled loudly when playing test sweeps. Sub-bass and bass frequencies make the woofer mechanically knock as if it was bottoming out. It also knocked from bass-heavy music during our initial listening tests. Knocking occurs when the voice coil (the copper coil responsible for turning a fluctuating electromagnetic field into the physical motion of the cone) exceeds its design limits. The Meridian woofer exceeded its limits by a lot at modest playback levels. Not impressive.
- The driver-side door panels rattled and buzzed with bass and mid-range frequencies, driving RivianBowerbird nuts—as it should. To reduce the noise, he put adhesive felt strips in several places between the door panels. It helped, but the buzzing remained too loud to ignore, breaking the spell that good music and sound create. During our early listening tests, he had to put his fingers on the door panels to stop the distracting buzz. Again, not impressive.
Results, Recommendations, and How to Interpret a Frequency Response Graph
Here is the reference measurement with markup highlighting problem areas.
The graph shows frequency (x-axis) plotted against dB or volume (y-axis). In an ideal world, the graph would show a smooth line from 20 Hz to 20 kHz without big bumps and dips. The green line helps us visualize what that “ideal” frequency response might look like. It’s taken from Harman Audio’s research of people’s preferences. The closer a measurement is to a target curve like this one, the more balanced and clear the system will sound.
The target curve isn’t ruler flat (i.e., does not have a zero slope) because people tend to prefer relatively more bass and relatively attenuated high frequencies. This has to do with the fact that human ears have different sensitivity to different frequencies; namely, we have a much harder time hearing bass frequencies than mid-range frequencies, even when they play at the same volume. This phenomenon is known as the equal-loudness contour. We need a lot more bass to perceive it at the same level as 1 kHz so we tend to prefer boosted bass.
As you can see, the R1T Meridian wasn't egregiously far off from the Harman target curve in most areas. However, it had problems.
The R1T Meridian's main problems were:
- A huge 8-10 dB bump in bass between 20 Hz and 250 Hz that caused rattling and buzzing. I love bass more than the next guy (see the above description of my home system’s bass output) but boosting bass this much masks adjacent frequencies, making music sound muddy and boomy. Low frequencies hang around in the air longer than high frequencies. The more low frequencies are boosted, the longer they hang around until they reach a volume we can’t hear anymore, causing boominess and making nearby frequencies hard to distinguish from the bass. I strongly suspect Rivian boosted bass in this way to give customers an initial impression of sound quality, much like TV manufacturers set their displays to "Vivid" mode in showrooms, which cranks brightness and hyper-saturates colors, to catch your eye. Bass impresses more than other frequency ranges.
- A sharp 12(!) dB rise in bass between 250 Hz and 150 Hz. Outside of contributing to rattling/buzzing and boominess, the sharpness of the rise masks adjacent frequencies more strongly, making instruments with important information in the 250 - 500 Hz range—such as rhythm guitar and the chestiness of male vocals—difficult to separate from the bass. Think about this as a sharp cliff face that blocks more sunlight from reaching a campsite at its base than a round hill would.
- Mid-range frequencies between 600 Hz and 3 kHz were attenuated by 3 dB from the target curve and from the frequencies immediately to the left and right of that range, causing noticeably indistinct vocals. Most vocal information lives in the 350 Hz - 4 kHz range. Other than the rattling panels, recessed vocals were the first thing I noticed about the Meridian system.
- Big drop past 18 kHz. This wasn't a surprise and was likely due to Bluetooth data compression. I had the same result from my R1S Elevation.
How do we address these issues?
Unfortunately, we can only address them coarsely because the Rivian system doesn’t allow us to change the frequencies we boost and cut. We’re stuck with the frequencies they give us. However, the R1T Meridian system was properly designed (outside of the rattling issue, which we'll get to), so it doesn't require a lot of surgical intervention (unlike the R1S Elevation).
After experimenting with several EQ settings, here’s where I landed:
- To address the huge 8-10 dB bump in bass between 20 Hz and 250 Hz that caused rattling and buzzing, I cut 63 Hz 3 dB. That largely eliminated the rattling problem from the 6"x9" woofer and door panels, even when we played bass-heavy tracks at meaningful levels. I'd need to do more extensive testing to say whether this change eliminates that rattling under all conditions, but it worked for us. RivianBowerbird was quite pleased with that result. In addition, the majority of muddiness and boominess that RivianBowerbird and I heard disappeared, improving the clarity of bass instruments, like kick drums and bass guitars.
- To address the sharp 12 dB rise in bass between 250 Hz and 150 Hz, I cut 125 Hz by 3 dB. While 125 Hz isn't within that range, cutting was an effective way to make the rise in bass more gradual. You might wonder why I didn't cut 250 Hz. I experimented with that but decided that it removed too much chestiness from vocals, leaving them sounding hollow. The reason for that is the deep valley at 265 Hz was already 4 dB too low. Cutting it more turned it into an audible problem. This is the one part of the Meridian response curve I wish I could address with a parametric EQ. RivianBowerbird noticed an improvement in vocal and instrument clarity and a reduction of muddiness from the 3 dB cut at 125 Hz immediately.
- To address the 3 dB attenuation of mid-range frequencies between 600 Hz and 3 kHz, I boosted 1 kHz and 2 kHz by 3 dB each. That lifted the range where the majority of vocal information lives, making a significant improvement to vocal clarity and overall balance across the full sonic spectrum of the music we listened to.
NOTE: RivianBowerbird didn't have the highest-quality tier of TIDAL, so we couldn't test the Meridian system's full resolution. However, I suspect the Meridian system may sound better than what I heard using a higher-quality source.
Comparison of R1T Meridian and R1S Elevation Systems
Now that I've made an objective comparison of the R1T Meridian and R1S Elevation systems, I'm more convinced that the Elevation system was misdesigned. My hypothesis was, and remains, that Rivian engineers swapped out the Meridian speakers for Elevation speakers without modifying the cross-over to suit, creating significant response issues at the standard cross-over range around 1 kHz that the Rivian's EQ cannot fix. (See the sister article for details about that.) The difference above 6 kHz is also explainable by a failure to modify the electronics after swapping the speakers.
However, the results are still inconclusive because other differences between the R1T and R1S, like cabin size and the number of speakers, could explain the performance difference between the Meridian and Elevation systems. The most conclusive test would be comparing an R1S Meridian to an R1S Elevation system.
Anyone in or around Austin willing to get their R1S Meridian measured?
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