Open Back vs Closed Back Cabinet: How They Sound
An open back cabinet spreads sound in all directions and sounds airy, open and three-dimensional, with a looser low end. A closed back cabinet pushes all the sound forward, with a tighter, punchier low end and more focus. Open back suits clean, vintage and edge-of-breakup tones and smaller stages; closed back suits tight rhythm playing and very high gain at volume.
Why the back panel changes the sound
A speaker cone produces sound from both sides. The front pushes air towards the audience; the back produces the same wave in reverse.
- In an open back cabinet, the rear wave escapes into the room. At low frequencies it partly cancels the front wave, so the deepest bass is lighter. The sound reflects off the walls behind and around the cabinet, which makes it feel bigger and more spread out.
- In a closed back cabinet, the air inside is trapped. It acts like a spring behind the cone, which controls the speaker's movement. You get a firmer, tighter low end and a more focused beam of sound to the front.
Open back: airy and three-dimensional
Open back cabinets have a reputation for warmth and sparkle. Because the sound comes from the front and the back, you hear more of the room. Many players find this more natural and easier to listen to, especially with clean and lightly driven sounds.
Other advantages:
- You hear yourself better on stage, even when you stand to the side of the cab.
- The sound fills a small room evenly instead of beaming at one spot.
- Open back cabinets are usually lighter.
The trade-off: the low end is less tight at high volume, and with very high gain the bottom can feel looser.
Closed back: tight and focused
Closed back cabinets give you that punch in the chest. Palm-muted rhythm parts stay tight, and the low end holds together at stage volume. They are also popular for recording heavier styles because the sound is direct and controlled.
The downsides are a narrower sweet spot and a more directional sound. Standing right in front of a closed back cab at ear level can sound harsh, while a few steps to the side the highs drop away. On stage, that can mean the audience hears something quite different from you.
What about half-open or tuned backs?
Between the two extremes there are partly open designs. A tuned or oval-shaped opening lets some of the rear wave out while keeping more control over the low end than a fully open back. This gives you much of the open, room-filling sound, with a bit more firmness in the bass.
Kool's current cabinets all use an oval open back. The Vintage open back 1x12 Cabinet has a tuned, oval-shaped open back and a Celestion G12H75 Creamback. The lightweight 2x12 and the vertical 2x12 both have an oval open back with a Celestion G12M65 and G12H75 Creamback pair. Kool describes the sound of the 2x12 as three-dimensional, with a full, spongy low end and warm, fat mids.
Which one matches your style?
- Clean, blues, roots, indie, classic rock: open back is usually the most natural fit. It flatters dynamics and the sound of the room.
- Edge-of-breakup and pedal-based sounds: open back again, especially with a clean pedal platform amp like the Blue Sky or a vintage-voiced amp like the Ace.
- Modern high gain and tight rhythm work: a closed back cabinet keeps the low end firmer, especially at volume.
- Recording: both work. Open back cabs pick up more room; closed back cabs give a drier, more direct sound. Read how to mic a guitar cab for placement tips.
Your amp matters as well. An amp with a lot of clean headroom and a tight low end can make an open back cabinet sound firmer, while a looser, vintage-voiced amp gets even more bloom from one. If you can, try your own amp with both types before you decide.
Speaker count matters too. A 2x12 open back has more low end than a 1x12 open back, which narrows the gap with a closed back. See 1x12 vs 2x12 vs 4x12.
Pick your cabinet
If the open, three-dimensional sound is what you are after, start with the open back 1x12 for a compact rig or the vertical 2x12 if you want more low end on a small footprint. Each cabinet is handmade in the Netherlands. For advice on which cab suits your amp, contact Kool.