How do Ekho wireless sounder tones compare with wired ESP sounder tones?

Direct answer

They overlap, but only on some settings. The sounders built into EK-WL8-HS and EK-WL8-OS produce three fundamental frequencies — 3 500 Hz, 2 150 Hz and 1 000 Hz — and only the 1 000 Hz settings fall inside the 500 Hz to 1 000 Hz range that BS 5839-1 recommends for the fundamental frequency of fire alarm sounders, although the same recommendation accepts frequencies outside that range where background noise would mask them. The EK-WL8-SND wireless wall sounder works at 990 Hz and 650 Hz, so all of its settings fall inside that range, and its two-tone setting is almost identical to Tone 34 of the wired ESP sounders. The EK-WL8-OV goes further: its default message 1 is 925 Hz and 628 Hz alternating every 250 ms, which is exactly Tone 1 of the wired ESP sounders. Where the wired and wireless devices in a building need similar sound characteristics, the EK-WL8-OV and the EK-WL8-SND are the closer matches.

Applies to

• Products / Models: EK-WL8-HS, EK-WL8-OS, EK-WL8-SND, EK-WL8-OV (Ekho hybrid wireless devices); EK-WL8-TRH (Ekho translator); wired ESP sounders such as CHQ-WS2, CHQ-WBS2, YBO-BS and YBO-BSB2
• Firmware / Version: All versions
• Region: UK / Europe
• Standards: BS 5839-1 (system design); BS EN 54-3 (sounders); BS EN 54-23 (EK-WL8-OV visual alarm device); BS EN 54-25 (radio links)

Wireless sounder settings

The EK-WL8-HS and EK-WL8-OS patterns are selected for the whole system. The EK-WL8-SND tone is selected on the unit itself, and the result also depends on the alarm sound selected for the system. The EK-WL8-OV follows the translator's message setting, which is separate from the alarm sound setting, so it is chosen independently of the tone sounders.

Only the settings listed above are approved for the EK-WL8-OV. Its tone library holds 58 entries, 51 of which are the same as the wired Hochiki base sounder tones, but loading a different one requires the Ekho Configuration software with the OrpheyRLib utility and a Programmer-PRO tool, and takes the device outside its approved configuration. The EK-WL8-OV is rated at more than 91 dB(A) at 1 m, but the per-tone tables in its installation manual give a minimum of 85 dB(A) to 90 dB(A) at 1 m for default message 1, so use the tables rather than the headline figure when checking coverage. It stays synchronised with the other devices on the system to within 50 ms.

Closest wired ESP equivalents

Tone numbers are those of the CHQ-WS2 wall sounder. The full list of 51 tones and the sound pressure level for each is in Application Note 084.

What this means for a mixed system

The alarm sound is one setting shared by every sounder on the system, so the wired and wireless devices cannot be given unrelated tones. In practice this leaves two options.

• Two-tone signal. Use EK-WL8-OV sensors on default message 1 with the wired sounders on Tone 1; the signals are identical and the EK-WL8-OV stays synchronised. Where a wall sounder is needed rather than a sensor, the EK-WL8-SND dual tone with the wired sounders on Tone 34 is the closest alternative, but that setting is not synchronised with the other sounders.
• 1 kHz signal. Set the system to the 1 kHz continuous or 1 kHz pulsed alarm sound and the wired sounders to Tone 25 or Tone 39. Every sounder stays synchronised, but check the sound pressure level before relying on the sounders built into EK-WL8-HS and EK-WL8-OS for the audible warning: on patterns 8 and 9 their minimum output is 77 dB(A) to 89 dB(A) at 1 m, which leaves little margin against the 75 dB(A) at the bedhead that BS 5839-1 recommends where the system has to rouse people from sleep.

Sound pressure level also has to be matched. The sounders built into EK-WL8-HS and EK-WL8-OS are rated at more than 96 dB(A) at 1 m, but that headline figure only covers the 3 500 Hz patterns 1 to 7, and even there the per-angle tables in the installation manuals fall to 87 dB(A) at 1 m at the extreme angles. On the 1 kHz patterns 8 and 9 the installation manuals give a minimum of 77 dB(A) to 89 dB(A) at 1 m depending on the measurement angle, so the 1 kHz setting is roughly 10 dB quieter. No volume adjustment is described for either device in its installation manual. The EK-WL8-SND is rated at 93 dB(A) at 1 m, but its installation manual gives a minimum of 80 dB(A) to 93 dB(A) at 1 m depending on the measurement angle, and it has a volume control that lowers the output further, the EK-WL8-OV is rated at more than 91 dB(A) at 1 m but gives 85 dB(A) to 90 dB(A) at 1 m on default message 1, and the wired ESP sounders are set by volume code, so the level can be brought to what the design requires.

When to contact technical support

Contact Hochiki Europe technical support to confirm the tone and volume settings for a specific mix of wired and wireless sounders, if the sound pressure levels or the sound characteristics required by the design cannot be achieved on site, or if you have not completed Ekho training. Formal training is required to design, install and commission Ekho systems. For warranty terms and the returns procedure, see Warranty, Returns & Support.

References

• Application Note 084 — CHQ-WS2 Wall Sounder Tones & Volumes (AP084, Issue 4)
• EK-WL8-SND Wireless Sounder installation manual (STFV.425412.001-E-UM)
• EK-WL8-OV installation manual (STFV.425238.037-E-UM)
• EK-WL8-HS and EK-WL8-OS installation manuals (STFV.425238.038-E-UM, STFV.425238.035-E-UM)
• Can you use a mix of wired sounders and wireless Heat / Optical sounders?
• Why do my Ekho wireless devices not appear on the fire panel loop?
• Why does my Ekho EK-WL8-OUT output module not operate during testing?

The installation manuals listed above are not published documents. Where a data sheet and an installation manual disagree on sound pressure level, as they do for EK-WL8-HS and EK-WL8-OS, the installation manual is the source to use.

Safety note

This article is general guidance for Hochiki Europe products. Design, installation, commissioning, maintenance and modification of fire detection and alarm systems should be carried out by, or under the responsibility of, a competent person in accordance with the applicable standards (for example BS 5839-1 in the UK). Statutory requirements imposed by the relevant enforcing authority also apply. Always refer to the current product manual and data sheet for the exact model before carrying out any work.

Last reviewed: 2026-10-09 — Reviewed by: Hochiki Europe Technical Support