Speaker Building Competition 15.06.13


A roll of gaffa tape, some toilet-roll inners, a few beer cartons, a speaker of questionable pedigree: Your mission, should you choose to accept it, is to build a great sounding speaker box in 60 minutes. This caption will self-destruct in five seconds…

So, as we draw a curtain of finality over SoundClub, we go out in a paroxysm of Blue-Peter style fun-with-sticky-tape. Details below, but before we do that – and for new readers – the agenda and preamble:

SoundClub is an approximately monthly session where a self-selecting group of interested people participate in skill sharing around the general theme of audio and technology, and sometime get their hands dirty fixing broken bits of the 1in12 Club PA system. See other blog entries for some history on that. Each session nominally starts with an agenda-setting exercise (called WAWAWDWWTFT – who are we and what do we want from this) where we have the opportunity to tear up the tentative agenda below – for example, the speaker building is nominally down for 1.30 but if that clashes with your other plans for Saturday afternoon, make sure you’re there at the start to give the timetable a nudge in your direction.

So, tentatively and subject to the outcome of WAWAWDWWFT

9.30 Рa weary bloke carries a load of audio paraphernalia  into Albion Street, puts on the coffee machine, and sets up a flip chart.

10.30 – doors open, introductions, WAWAWDWWFT

11.00 – a look at some actual speakers (not broken ones like previously, but some actual still-working chassis speakers out of their boxes). Why is one cheap and one expensive; poking, prodding, discussion.

11.30 – soundquiz / any questions ?

12.30 – Lunch, if you want it

13.30 – Speaker building contest

14.30 – Winners and Loser

15.00 – the end.

Speaker design/build contest:

Success criteria:

  • Sounds good
  • Durable
  • Useful

Sounds Good: will mainly be judged by other participants (can’t vote on their own work, strategic voting to nobble contestants will be punished severely). However, there may also be measurements of comparative loudness (for a given input signal) frequency response and phase integrity.

Durable: look, it’s going to be made of gaffa tape and cardboard so the threshold of acceptability is quite low, but it needs to not fall over under its own weight, and be capable of being picked up and moved around. A rigid structure will, in any event, sound better.

Useful: Ideally you could image taking it home and listening to the radio through it on your workbench, or similar. If you end up with a radically innovative design that’s a metre long and four inches wide so you can never really find a place to use it, points will be lost, unless it sounds so amazingly good that difficulties using it are worth overcoming.


Most importantly, do some research and have a plan (but see comments about teamwork below). If you’ve an idea about approaches you might take it’ll really help, so your no. 1 material is the knowledge and planning you’ve already done.

Cardboard – exact specifications t.b.c. But probably one Budvar box and one Sam Smiths ale box, may include Becks’ Blue and a soya milk container.

Toilet roll inner (in case you wish to attempt a circular bass port).

Gaffa – 1 roll. You don’t need to use it all.

Speaker – details to follow, but small and light enough to not crush the box. Probably 5 or 6 inch dia.

Baffle board – a pre-cut piece of hardboard with a circular hole for speaker mounting.

Some kind of craft knife to cut the cardboard: don’t cut yourself, and keep away from children and pets, ok?


Participants will work either individually or in teams (depending on numbers). If you’re in a team you’ll be expected to behave co-operatively, and points will be be awarded/deducted accordingly.

If fewer than three people attend we’ll make a new plan.

The contest will last an hour (1.30. – 2.30) with judging and discussion afterwards.

You can take your speakers home afterward; if there are more contestants than speakers we’ll have an auction, proceeds to the PA Collective.


Do some reading on speaker cabinet types: Infinte Baffle, Bandpass, Reflex etc. – figure out what you think might be possible in the time available.


The speaker building contest, like SoundClub, is free, though if you want to make a donation to the PA Collective for materials that would be very useful.

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