An electric humming vibrator designed to upset neighbours operated for about a month inside New Zealand’s tallest apartment tower, sending 25 neighbours “just about insane” before it was discovered and disabled, a resident says.

Management of downtown Auckland’s The Pacifica sent a notice thanking people for their patience while matters were resolved but refused to talk to the Herald about it directly, citing privacy.

A photo of the device, which emitted humming vibrations, showed it jammed between two books and the top of an internal window, high up in the $300 million 57-level luxury apartment block.

A close-up of the head of the vibrator inside The Pacifica. Photo / supplied

The Pacifica: New Zealand's tallest apartment tower. Photo / Michael Craig

The device was plugged into the mains and had a metal rod nearly the height of the window and a purple plastic device on the end.

A resident explained a man had installed it in a window cavity, behind a blind, specifically to aggravate his upstairs neighbours for unknown reasons: “The device causes a low vibrating-type hum at about 35-40 cycles per minute at about 80hz. It sounded like a cellphone ringing on vibrate stuck in the wall, but it never stopped and just continued all day, all night.”

Investigations took weeks until management discovered the device, the resident said.

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“I’ve been told it’s a ceiling vibrator V2 version, vibrating and knocking. It just about sent 25 residents insane because it took a month for it to be located. Everyone thought it was an electrical or mechanical issue that created a dull, repetitive noise 24 hours a day. I know of residents who couldn’t sleep and abandoned parts of their apartments,” the resident said.

This notification went to Pacifica residents after the electric device was discovered and disabled.

Chris Ivers, Pacifica body corporate chairman, said: “Due to privacy, I can’t discuss matters relating to individual apartments and residents.”

Ceiling vibrators have a long, height-adjustable rod to run from floor to ceiling and make vibrations or a knocking noise from the head. They can be remote controlled and once switched on, they transmit to upstairs neighbours. Thumpers were said to be invented in China and are sometimes referred to as “noisemaker revenge machines”.

The ceiling vibrator device was found inside The Pacifica.

What action the management is taking against the vibrator-using resident remains unknown. Whether they owned or rented the unit is undisclosed.

“Earlier when they had located the noise close to the apartment they asked for access and now believe the owner turned off and hid the unit when the apartment was inspected for the cause of the noise. This is why apparently it took so long to locate it,” the resident said.

The Herald reported last month on the building residents’ annual general meeting. Ivers cited fire sprinklers flooding apartments, hard water stains on windows, rubbish chute blockages and construction defects as issues residents have dealt with.

“Significant issues were the sprinkler floods and black water events. In general, the sprinkler floods were due to tradespeople or objects hitting sprinkler heads,” Ivers said of the tower, between Commerce St and Gore St. The issues have now been resolved.