Vibration exists everywhere in our environment. The goal of a vibration control device is to reduce noise (unwanted vibration) affecting the audio system and reveal the music (good vibration) being played through the system.
This White Paper explains why Gingko Audio’s Cloud22 Base works better than other commonly-used vibration control devices. As illustrative data points, we present vibration measurements that show performance differences between the Cloud22 Base and conventional metal spikes used under speakers and electronics.
The Cloud22 Design and Construction
The Cloud22 products use wool, in the shape of a ball or hemisphere, as vibration control material. When compressed under load, the wool fibers turn vibration energy into heat. The inert structure and composition of wool do not have a natural resonance that can add spurious vibration and smear the sound. The background noise across the audio band is greatly reduced. A lower noise floor helps to separate individual parts of the recording.
Listening tests indicate a more expansive and pinpointed soundstage. The music is livelier, with more dynamics in the mid-range, tighter bass, and extension in the top frequencies. The clarity in the music makes lyrics on some recordings more discernable.
Comparison to Metal Spikes
Most speakers and some audio components use spikes as a vibration control device to isolate vibration coming from the shelf/floor to the component. However, as noted in our White Paper on ARCH Performance, spikes create their own problems.
First, the complex vibrations from the component chassis or speaker when it is playing music are channeled through the spikes to the shelf/floor. Some of the vibration energy reflects back through the spikes to the chassis/speaker, typically out-of-phase with the original vibration, which again is channeled down to the shelf/floor. When the music is played loudly, airborne vibration also causes the shelf/floor to vibrate, especially on suspended wooden floors. Because spikes are excellent transmitters of vibration, they affect the component chassis or speaker cabinet in a negative way, causing the sound to be smeared.
Second, most spikes are made of metallic material, which may add its own resonance to negatively affect the sound.
Vibration Measurements
For our vibration measurements, we use two B&K 4366 accelerometers feeding signals through two B&K Type 2626 conditioning amplifiers to a PC running Richard Horne’s Spectrogram software. The Spectrogram software can be downloaded from this website. We play test tracks through a powered Vanatoo Transparent One speaker.
Below is a picture of the test setup with the two nearly identical accelerometers shown in the lower-left corner, on the (solid maple) table surface.
Test Tracks – We use Pink Noise as one of the test tracks. The second test track is music from “Cry” by Anna Calvi on the “One Breath” album.
Spectrogram Data – In each of the spectrograms shown below, elapsed time is on the horizontal axis. The vertical axis represents frequencies in a logarithmic scale from 30 Hz to 22K Hz (we choose not to capture frequencies under 30 Hz because the speaker and PC sound card are not capable of registering lower frequencies). The vibration energy is depicted using colors, the hotter the color the more vibration energy: Red denotes the most vibration energy, followed by orange, yellow, green, blue; white denotes insignificant vibration energy. Generally speaking, background noise is almost always blue, reflecting its low energy content. The black line at the top of the graph shows the sum of all the vibration energy across all frequencies.
Test Runs – After a baseline run to verify that the two accelerometers are nearly identical (Test #1), we conduct several tests: No vibration control device under the speaker (Test #2); metal spikes under the speaker (Test #3); Cloud22 bases under the speaker (Test#4). Note that we could run similar tests with any other vibration control device, which we often do for vibration control demos at audio shows.
In all the side-by-side comparisons, the spectrogram on the left corresponds to the accelerometer marked with the blue tape. The spectrogram on the right corresponds to the accelerometer with the silver top.
Test #1 – Baseline: Both Accelerators Placed on Table Surface
To establish a vibration measurement baseline, we place the two nearly identical accelerometers directly on the table surface.
In both the left and right spectrograms, the first part shows the background noise picked up by the accelerometer with no test track being played. In the second part, the Pink Noise track is being played by the speaker. The 60 Hz signal horizontal line from the B&K amplifier’s transformer is picked up by the accelerometers, as are its multiples at 120 HZ, 240 Hz, etc.
Next in the baseline test, we play music from “Cry” by Anna Calvi to again demonstrate that the two accelerometers are registering nearly identical signals.
Test #2: No Vibration Control Device under Speaker
For this test, we move the accelerometer with the silver cap from the table to the top of the speaker, while the accelerometer with the white cap (marked with blue tape) remains on the table surface. The speaker sits directly on the table surface with no vibration control device under it.
As noted above, the spectrogram on the left corresponds to the accelerometer with the blue tape; the spectrogram on the right corresponds to the accelerometer with the silver top.
We follow the same procedures as in the baseline runs: First, we run a test with no music played. For the accelerator placed on the speaker, the spectrogram shows less vibration from background noise compared to the spectrogram for the accelerator kept on the table surface.
When the Pink Noise is played next, the spectrogram for the accelerator on top of the speaker shows vibration from the Pink Noise. Since much of the Pink Noise vibration is transmitted through direct contact between the speaker and the table, a lot of the Pink Noise vibration is also shown on the accelerometer on the table.
We run Test #2 with “Cry” by Anna Calvi as the test track. Again, note that a lot of the music played through the speaker (right side) is transmitted onto the table as registered by the spectrogram for the accelerator kept on the table surface (left side).
Test #3: Metal Spikes under Speaker
For this test, we place three metal spikes under the speaker. The difference between the spectrograms on the left and right side of the split screen would show how well the spikes work to isolate the speaker from the table.
With no music played, the spikes do isolate the speaker from background noise. But when the Pink Noise is played, much of the speaker vibration shows also on the left spectrogram, proving that the spikes transmit speaker vibration to the table and provide only minimal isolation. As vibration is transmitted in both directions, it is also possible that some of the reflection from the table back to the speaker has negative effects on the speaker.
With “Cry” played on the speaker, the music is still being transmitted through the spikes onto the table but less than in Test #2 because the spikes do provide some isolation.
Test #4: Cloud22 Bases under Speaker
For this test, we put three small Cloud22 Bases under the speaker.
The spectrograms from the tests show that compared to the spikes, the Cloud22 bases provide more isolation in both directions (up to the speaker and down to the table).
- The background noise picked up by the accelerometer on the table is much less visible in the spectrogram for the accelerometer on the speaker. This proves that the Cloud22 bases do a good job of isolating the bad vibration (background noise) away from the speaker.
- The effect of the 60 Hz signal from the table is also greatly reduced on the speaker.
- The vibration from the Pink Noise being played by the speaker is greatly reduced on the table, again proving that the Cloud22 bases do a much better job in preserving the good vibration on the speaker.
With “Cry” as the test track, the spectrograms show that the vibration on the table (left side) is greatly reduced, compared to the music being played on the speaker (right side).
Conclusion
The above test results prove that the Cloud22 bases do an excellent job of isolating the speaker from the table, compared to no vibration control or metal spikes. Similar tests can be conducted using different vibration control devices, like footers or platforms. Suffice it to say that we are confident that the Cloud22 bases do a great job, compared to other devices at a fraction of the cost.
Every system and listener may react differently to the effects. That is why we offer a no-questions-asked, 30-day money back guarantee. We want you to return the Cloud22 products if you are not 100% satisfied as we only want delighted customers.
Email us at gingko@gingkoaudio.com if you have any questions or feedback for us. We love to hear from our customers.