Attraction Call Systems for Swifts

If you arrive here, first check out the Swift Micro caller:
This is a summary of a Swift attraction call system based upon the Cheng Sheng (or equivalent) Player Amplifier. This system has been something of a game changer because of its ease of installation, ease of operation and effectiveness.  We also cover when to play attraction calls and solar-powered battery-driven systems.

The playing of attraction calls is the nearest thing to a 'silver bullet' in encouraging Swifts to occupy new nesting places.

The Cheng Sheng player-amplifier
[Note Cheng Sheng is no longer on the market, but there are a number of similar altenatives] 
The components needed are low cost, easy to install and easy to control with a digital or mechanical timer. Calls, in MP3 format, can be held on an SD card or a USB memory stick.

Components of attraction call system

The Cheng Sheng player amp can also run off a 12 volt car battery, with solar panel, described below.

These configurations are easy to put together yourself: 
[1] Plug in the power adapter
[2] Use solder or a small connection block to attach the tweeters to the speaker cable.
     Attach 1 (or more) tweeter(s) (polarity does not matter). 
[3] Insert an SD card (or memory stick)
[4] Switch the power on, and it starts playing in a continuous cycle
We recommend setting the treble and base to maximum,

[The Cheng Sheng does not come with instructions to explain what the buttons mean, so we have written some here (File>Download for pdf)]

Websites for the components: 
We no longer list sources on this page, but we try to maintain an up to date spreadsheet 

Timer Switches
We recommend a 240 volt digital timer because it can survive loss of power without losing the time or program settings. We have used the Time Guard TG77 7 day timer. It is simple to program, is reliable, it has an on/off light and is available at a good price from John Lewis in the UK, see here.

Sources for Swift calls in MP3 format:
Netherlands Swift Protection downloadable calls recorded by Rosanne van Oudheusden. 

Rick Wortelboer uploaded the file 'Set of selected Swift' to the Files/Swifts section of SMSWW,; requires login. These are some of the same tracks as the previous link, with quiet periods inserted.

Swift Conservation well tried calls on CD and supplied in MP3 format.

It is also worth Googling for Swift calls, we found these:

12 volt battery-driven systems
Power polarity of the Cheng Sheng
If mains power is not available, then a 12 volt battery can be used. A car battery of 45 amp-hours should provide 100 hours of continuous running before recharging is necessary. The centre of the Cheng Sheng plug/socket connection is +ve.

If regular recharging of the battery is not practicable, the alternative is to add a solar panel.

Schematic showing component connections

Solar panel
We have used a 20 watt solar panel (costing £30) and a Morningstar SunGuard 4.5A voltage regulator (costing £28) from Midsummer Energy in Cambridge. This is sufficient to keep the player going for at least 10 hours a day.

Mount the solar panel at the optimum direction towards the sun: facing south, with the plane of the panel at 30° to the horizontal  

12V Digital timer
We recommend DC12V Digital LCD Power Programmable Timer Time Switch Relay 16A. It requires some wiring up, but is a low price, easy to program and works well. It is also available on Amazon.

When to play attraction calls
In all situations, attraction calls are essential to accelerate the process. As a sample of success, by 2014, 25 of 40 projects (62.5%) playing attraction calls had at least 1 pair of Swifts. However, nest boxes installed as a replacement for lost nest sites can be very successful, even without playing attraction calls.

Place tweeters close to the nest boxes where they cannot get damp e.g. on, under or in a box. Or from a sheltered window sill or even at ground level.

The attraction call season:
In the UK, the attraction call season runs from the end of the first week of May until the end of July.

Start about 7th May if you are providing boxes for displaced birds.
Start from mid-May if the situation is a new site, where there have been no breeding swifts. This is when prospecting young Swifts begin to arrive.

Experience has shown that playing calls during the second half of June and the first 3 weeks of July gives the most positive results.

Time of day to play calls
Play the calls from just after dawn until just before dusk. Early and late seem to be best.
Afternoons are probably the least productive, though any time of day in fine weather can be successful. 

Louder is better, but one may need to compromise with neighbours. Find a volume and playing time that keeps everyone happy.

To attract Swifts, persistence and patience are essential. The more and the louder your playing, the better your chances, but it may still take a year or three.

After you have attracted your first pair, continue playing to get more, you will not frighten established birds away. However, after a certain level of occupancy, you increase the chances of attracting intruders into occupied boxes, resulting in fights. If this happens, then it may be advisable to stop playing the calls.

So good luck and we hope you are successful in attracting these wonderful birds to nest. You will be richly rewarded for your efforts by magnificent flypasts for many years to come. N.B. Swifts and warm sunny weather go together like strawberries and cream! The better the weather the more swift activity and the better your chances of success in any given year!


  1. Still very helpfull post! Thank you for sharing this info!

  2. Further to this:

    ...thanks for the reply, Dick. I'd imagine some mp3 sounds are better than others at blending into the background so as to be effective in calling swifts but at the same time not annoy neighbours? What sort of time interval do you leave between repeated calls? Possibly all a bit belated now though as the swifts aren't around so much now! :(


    1. The calls that I use are a medley of the Dutch calls, with only short gaps in between. I don't know of any experiments as to how gaps of varying length might affect effectiveness.

  3. These systems are great - small and effective !

  4. Put together the caller system earlier this year, worked very well with solar charging of a leisure battery powering it, however the tweeters suggested were of tragically poor quality and were quickly returned and replaced with the Amazon item below, these gave amazing crystal clear results after mounting in the bottom of a plastic beaker which weather protected them plus acted like a small megaphone, overall a great package with the replaced tweeters.

    1. Which tweeters gave poor sound? All of the tweeters that we recommend we have tested and are of good quality. Please get in touch via

    2. Which tweeters gave poor sound? All of the tweeters that we recommend we have tested and are of good quality. Please get in touch via


    Small but effective and extremely clear and powerful, really will fit anywhere, and will tilt back and fourth, with built in filter it cant be faulted at this price,
    Under £5 !!!

    1. We have used these on a number of projects, as you say, they are very good.

    2. These tweeters are currently unavailable from Amazon, can you suggest another alternative?

    3. Get in touch via our email address and we may be able to help you.

  6. Hi.At the tail end of last summer built and erected a swift tower with 15 nest boxes and a further 3 fitted to the cottage wall. Initiated calls created amazing results after only 1hr. Hopefully the birds will visit again soon!