A-level sub project

Im thinking about building a horn cab, along the lines of the 1850.  I know its fairly large but it produces the frequency range I require and all the other plans on the site seem to have flaws which make them unsuitable.  Just wondering what drivers would be suitable for it, considering my budget is fairly limited.

Thanks

Chris

Just exploring all the possibilities at the moment.

Thinking about it a reflex enclosure would be a good option.

What design would you recommend and also what drivers (around 1k RMS)

Thanks

Chris

Relfex cabs look fairly easy to design and build, is this the case?

I really need to design my own cab in order to fit the criteria for the project.  When I have chosen a driver what will I need to calculate in order to design a cab.

Thanks

Chris

Once you've chosen a driver you need to decide what cabinet volume you want, 0.7, lower bass, or smaller and a bit more boomy.

Then there are one of the sets of magic number ratios to consider, to avoid internal reflections producing a bias at particular frequencies.

Then, for a reflex cabinet, you need to work out the tuning of the port, length largely determines frequency, and area determines port velocity.

Then, if you need to stretch some more calculations, there is the weight of the cabinet, you might like to target <=25kg for a single person lift.  You can also calculate the dB response for a given input power, and how this will decrease the further away you get from the speaker.  After that you can try to get minimal wastage from sheet material ...

I've got two double 15" reflex and some HD15 horns with two driver types.  I use the HD15 as a small far throwing bass unit rather than building up large arrays, so the reflex does go lower, but both have their place.  Hope the above gives you some ideas about what you could include in the project for a reflex design, for the HD15, ask expert Rog.

Some rough budget costs:

Driver: £50 - £350

Timber, glue and screws: £100 (Quality sheet cut at Timber merchant, not a DIY shed)

Handles and fittings: £50 (Excluding corner protection)

Since an empty unpainted box without corner protection costs £150, it is worth putting in a reasonable driver if you can, say £150, so you are looking at £300.

For your project you could factor driver cost, Max SPL, Fs, etc in making your choice.  Also, you could chose an "ideal" speaker but then use a cheaper one and state your results with the cheaper unit.