CompIQ Stella Pro Compressor

This is why we rename the CompIQ Stella’s equalization control “X-EQ”

On June 22, 2020, we received an email from a representative of PMI Media Group, notifying us that the term TILT™ is a registered trademark in the United States. The trademark is owned by AMH Sales, Inc. doing business as PMI Audio Group Corp., under Class IC 009 registration #3971079.

PMI Media Group is a manufacturer of professional audio equipment and produces products under various brand names such as Joemeek, Trident Audio Developments, Toft Audio Designs, Studio Projects, Tonelux, and Valley People, as stated on their website.


verb: move or cause to move into a sloping position.
"the floor tilted slightly"
noun: a sloping position or movement.
"the tilt of her head"

The equalization control on the CompIQ Stella compressor pedal is designated as “tilt,” which describes the function of an electronic component arrangement utilized in audio products worldwide, including those produced by PMI Audio Group. This arrangement is widely known as a “tilt eq filter” in various internet publications, owing to its effectiveness and simplicity.

We aim to name our controls based on their intended functions, as evidenced by our labeling of other controls as “ratio,” “threshold,” and “gain,” all of which accurately reflect their roles and purposes.

We initially believed that a noun could not be trademarked to secure the use of a term that is part of technical knowledge. However, we were recently informed that we are not allowed to use the word “tilt” to describe the functionality of the tone control without discussing royalties or removing any references to the TILT™ name within 90 days.

In response, we explained to PMI Audio Group that the circuit topology is not proprietary to any entity, nor is it protected by patents. Although they cannot trademark or register the circuit, they have registered the name. We were cautioned that continued use of the name would be a violation.

Our research indicates that QUAD HI-FI from the UK first employed the circuit and “tilt” label in 1970 in their QUAD 34 Preamplifier. We contacted QUAD HI-FI to inquire about the circuit’s history and are awaiting their response. For those interested in technical details, Mr. Ken Rockwell’s website features a comprehensive and detailed review of the product, including its tone control.

The QUAD 34 Preamplifier front panel. © 2011

We were offered the option to license the use of the noun “tilt” to label the tone control on the CompIQ Stella for a percentage of the product’s price. Additionally, we were presented with the opportunity to be listed on the PMI Media Group website as a “tilt” label licensee.

Initially, we considered licensing the use of the “tilt” term and sought legal advice. However, we were advised that such an action could inadvertently reinforce the perception that the circuit itself is exclusive to PMI Media Group, which is not the case.

Therefore, we have received legal counsel to choose alternative terminology to label the equalization control.

Our response

In a spirit of good faith, we have decided to rename the tone control on the CompIQ Stella as “X-EQ” going forward. In the coming period, we will take the necessary steps to change the label on the product, update the manual, packaging, website product description, and all relevant materials associated with it.

Disclaimer: The brand names and trademarks used in this post are the property of their owners.