Summary of Article:
- Both the Lightspeed Delta Zulu and the Zulu 4 deliver premium ANR (active noise reduction) performance and are backed with Lightspeed’s industry-best 7-year warranty.
- The Zulu 4 is the most recent headset in Lightspeed’s Zulu series and focuses on next‑generation comfort with FrameFit™ dual‑density ear seals, greater clarity with Bluetooth voice-isolation for outbound audio, and improved flexibility for pilots by adding a longer mic boom, a longer upper cable, and dual Bluetooth.
- The Lightspeed Delta Zulu is Lightspeed’s flagship premium ANR aviation headset with Lightspeed’s best active noise reduction to date, built‑in carbon monoxide monitoring and audible alerts, offering life‑saving safety technology no other headset provides.
- The LightspeedDelta Zulu includes HearingEQity® personalized hearing profiles for pilots who may struggle with hearing loss, to ensure no communication is misheard.
- The Zulu 4 emphasizes comfort and communication clarity at a lower price point.
- Both headsets share Lightspeed’s large ear cavities, stainless‑steel materials, multiple plug options, and premium ANR performance. This makes either headset a strong choice depending on a pilot’s priority to the safety features offered by the Lightspeed Delta Zulu or the premium comfort and value of the Zulu 4.
Safety Technology
The Lightspeed Delta Zulu stands apart as the first ANR headset with integrated carbon monoxide monitoring. With Kanari® smart alerts and continuous CO tracking, it provides life‑saving awareness and audible alerts for pilots flying with or without panel‑mounted detectors. While the Zulu 4 does not include CO monitoring, it focuses on advancing comfort and safety through clear communications.
Evolved Comfort: FrameFit™ Ear Seals
The Zulu 4 introduces FrameFit™ dual‑density ear seals, engineered to improve seal stability when wearing sunglasses, hats, or other headgear. The softer foam in the top half of the ear seals reduce pressure points and prevent seal breaks that may cause warbling in ANR systems when wearing other headgear. Both headsets share large ear cups and a low‑profile stainless‑steel headband for even weight distribution.
Focus on Clarity: Hearing EQity® and Bluetooth Voice-Isolation
The Lightspeed Delta Zulu offers HearingEQity®, a 12-frequency hearing test that creates personalized hearing profiles tailored to each pilot. Users can store multiple profiles and switch between them with ease.
The Zulu 4, while not including HearingEQity®, excels in outbound Bluetooth clarity using voice-isolation technology that removes up to 90% of background noise from outgoing audio like phone calls and in-flight recordings. This helps to ensure that every word you say comes through loud and clear, and cuts back on “say again” moments with ATC.
Equipped for Flexibility
The Lightspeed Delta Zulu and Zulu 4 both offer support for multiple plug configurations. The Lightspeed Delta Zulu also includes interchangeable battery options – pilots can choose between a rechargeable lithium‑ion battery and a cartridge for AA batteries.
The Zulu 4 adds dual Bluetooth so pilots can connect to two-devices simultaneously. Simply pause audio on one device and start it on the other without having to unpair and repair your devices. The Zulu 4 also offers a 10% longer mic boom for improved placement for better voice pickup, and a longer upper cable for cleaner cockpit cable-routing.
Which Headset Should You Purchase?
Both the Lightspeed Delta Zulu and the Zulu 4 are excellent choices for premium ANR headsets and offer industry-leading features and quality.
The Lightspeed Delta Zulu excels in safety features like CO monitoring and HearingEQity® personalized audio profiles, making it ideal for pilots who are prioritizing advanced safety and fine-tuned audio. The Zulu 4 offers brand new innovations in comfort, clarity, and flexibility. From Bluetooth voice-isolation, to FrameFit ear seals, the Zulu 4 is truly the next evolution in the Zulu series.
The Zulu 4 is currently available for $1,099 USD, and the Lightspeed Delta Zulu is available for $1,299 USD.
Do you still need help deciding? Take advantage of Lightspeed’s 30-day money back guarantee and try both headsets to see which one is right for you!







I need an Android app for the Delta Zulu before I can buy one!
Hi Don,
While we don’t currently offer an Android version of the app, your Lightspeed Delta Zulu will work as designed. An iOS device (iPhone or iPad with iOS 13 or higher) is only needed once—for initial setup of your HearingEQity™ profile and CO settings. After setup, your preferences stay saved in the headset, so no iOS device is needed for everyday use. Learn more here: Lightspeed Delta Zulu Support page.
The most important thing to me is Noise Cancellation.
What are the dBs of cancellation of these two headsets, and also the Bose headset?
Thanks,
Hi Tod! We do not publish noise cancellation levels in dB since that figure actually measures passive noise reduction, while the Zulu 4 and Lightspeed Delta Zulu (and the Bose you mentioned) use active noise reduction (ANR) to electronically cancel sound. Because ANR performance varies by aircraft type and cockpit environment, there’s no standardized way to express it in dB. For more information about how passive and active noise reduction differ, you can check out this article here: Passive vs Active Noise Reduction in Aviation Headsets. Also, in our ANR 101 Section 3 article we do show the dB level of an aircraft (red), against the noise reduction of a passive headset, and our ANR: https://www.lightspeedaviation.com/anr/anr-201-section-3-acoustic-design-tradeoffs/.