The second enclosure which I designed and built uses an Eminence 12" Delta Driver, which is rated at 300w RMS (8 Ohm and 98db/w/m). Again I used Speaker Box Lite (but this time I did what it said!) to specify the enclosure.

This box is a 67 litre (much more manageable) with a pair of 57hz tuned ports. This gives a nice flat frequency response and a nice low F3 of 56Hz. This time I used 18m/m chipboard and produces a much more solid enclosure but a bit heavier though. I used the same 1.6kHz passive crossover from Eminence and the same Monacor Mid range unit. In fact I used simular hardware for both cabs.

I usually use only one cab (it really is enough for most venues) which is this 12" cab. Although it has a lower power rating, 300w RMS against the 15" cab's 400W. It also has a lower efficiency rating (98db/w/m against 103db/w/m). But I find that it has a more detailed and clearer sound. It also doesn't need any EQ which gives it a smoother, more natural tone. This cab is also a bit smaller and manageable, but the same weight due to the thicker chipboard.

The F3 of 56Hz may seem a bit high for a 5 string, but it copes fine, remember that the bass is unique in that it's first harmonic is less than the second (which is at double the frequency). In fact the second harmonic is the strongest. No other instrument does this. So, in the real world, to produce a low "E" @ 31hz, a driver and cabinet must be capable of a minimum of 62Hz.

My Trace Head and 12" cab, small, tidy and very loud, this photo was taken before I covered it with green flock carpet. You can see some of the white acoustic wadding through the tuning port hole.

Costs

I built this cab in Feb1999 so the prices have probably gone up. All prices inclued all UK VAT and any postage charges.

1x Eminence Delta 12 £ 40.35

1x Monacor 2" Soft Dome mid range £12.75

Eminence 400w 1K6 2 way crossover £22.85

Corners, Grill, Rubber Feet, Handles,Conectors and Internal Wire £60ish

Chipboard, Screws, Glue, No-Nails and Wadding £32

Total Costs: £167.95