If you want to build a bass amplifier stack, then you don't just need a solid amplifier head, but a dedicated bass guitar speaker cabinet to back it up and a good speaker cable or SpeakOn cable to link them together.
A Speaker Cab for an Amp Head or Combo
When hooking a bass amplifier head or combo bass amplifier up to a speaker cabinet, you need to make sure that the cab is able to handle the power coming from the amp. If your amplifier delivers more power (in Watts) than the speaker cabinet can take, then you risk the chance of causing your cab - or your amplifier and cab - irreparable damage. Luckily, we have a vast array of different speaker cabinets on offer, across a wide range of power capacities so you'll be able to find the right match for your bass amp. Besides that, all you'll need is a dedicated speaker cable to link your amplifier and cabinet, since normal jacks leads aren't built for the high power level that the amp needs to send to the speaker.
Bass Speaker Cabinets: 8 Ohms or 4 Ohms?
It's also essential that the impedance of your speaker cabinet matches the impedance of your amplifier so that both elements of your stack are fully optimised to work together. At the right level of impedance, the bass amplifier gets the right amount of load and can do its job efficiently. You can actually combine a speaker cab with a higher impedance with a bass amplifier head or combo with a lower impedance, like an 8 Ohm cabinet with a 4 Ohm amplifier. The only possible issue is that this will lower the output volume a little bit. However, it's never a good idea to match a speaker cab with a lower impedance with an amp with a higher impedance. If you were to link a 4 Ohm bass cab up to an 8 Ohm amp, then the amp will need to work too hard, increasing the chance of transistor failure - and getting a transistor repaired isn't cheap. So, if you want to avoid any issues, it's just best to make sure that the impedance of your speaker cabinet matches the impedance of your amplifier.
2x 10 and 1x 15 Bass Guitar Speaker Cabinets
The most popular and therefore most well-known bass guitar speaker cabinets are classic 210 and 115 cabs. 210 (or 2x10) literally means two 10 inch speakers come built in, while 115 (or 1x15) means one 15 inch speaker comes built-in. If you want a bass sound with masses of definition, then a 2x10 cab will do it for you. If you want a really full bass sound with more bottom-end to it, then a 1x15 cab will be the better choice.
Custom 2x12 or 8x10 Speaker Cabinets
Besides 10 inch and 15 inch speakers, you can also get 8 inch and 12 inch speakers. With a 112 (1x12) speaker cabinet, you'll have a rig that'll make sure you slot seamlessly into the total band sound, while a 108 (10x8) cab will give you a more punchy sound. If you want a broader bass sound, then you're likely to prefer a 212 or 208 configured cab. Of course, if you need a bigger bass sound that still sounds tight, then a 4x10 or even an 8x10 will be more ideal - however an 8x10 cab is a big and heavy chunk of gear, so you might want to figure out how to get it to and from rehearsals and gigs before making the investment.
Compact & Lightweight Bass Guitar Speaker Cabinets
If you don't have the space for a massive bass rig or just want your back to survive the touring schedule, then a smaller and lighter amp setup simply makes sense, and these days you'll have plenty to choose from. You can easily pick up a great mini or micro bass amplifier head and combine it with an ultra-compact speaker cabinet to build yourself a manageable touring rig that even packs as much force as a full-sized stack. The list of these ultra-modern compact solutions is only growing, so it's worth keep an eye on the available range.
Cabs with a Tweeter or Bass Reflex Port
If you've figured out the speaker size you're after and know what kind of cab you need to combine with your amp but want a little extra punch on the side, then it's well worth opting for a speaker cab with a built-in tweeter. The additional tweeter will inject more bite into your tone while the rest of the speakers will take care of bulk of your bass sound. If you need to counter overbearing lower frequencies that are leaving your bass sounding a bit too woolly, then a cab with a bass reflex port will fix it. A bass port functions as a kind of low-end filter for all the lower frequencies that you don't need. Physically, it allows extra air pressure to be released as well as allowing air to circulate inside the cab, making it easier for the speakers to do their job. The benefit of using a cabinet fitted with a bass port is that it gives you bigger and even louder bass sound without having to nudge the volume up.
