MirrorProfiles
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Just some general advice that might be useful to those trying to get the most out of their space. I might add more in time, but it should be some helpful general advice that would apply to most people in standard rooms:
- try and set up against the shortest walls in your room. Keep things as symmetrical as possible on your left and right. 1st reflections need a lot of consideration, generally its best to have the sides as your nearest walls and the rear wall further away.
- speakers almost always want to be as close to the front wall as you can get them. Be aware of rear firing ports and heat dissipation from active monitors, although the angle of the speakers often leaves enough room for those to operate properly.
- keep the entire front wall reflective. Bass radiates in all directions at low frequencies, and to absorb in any meaningful way is going to require a lot of depth. Not going to happen. If you have the speakers close to the wall, the reflections you do get will be closer in time to the sound leaving the speaker. The speakers will also have more headroom/efficiency if they don't have absorption behind them. Put your panels in areas between you and the speakers - they'll be WAY more effective treating 1st reflections.
- measure your room, and also be aware of the axial room modes. Identifying the best positions to place your speakers AND your listening position is critical. The flattest position you can find with no treatment is likely to be your best spot even with lots of treatment. Often 38% gets mentioned online as the distance from the front wall where your best spot is likely to be. A good way to test is to place a single speaker in a front corner of the room, play some music you are familiar with, and gradually move backwards and forwards down the centre of the room. You'll notice the bass response change, and where it sounds most even is likely to be a good spot to listen from. You can measure with a mic and see if the response of the modes looks even. The goal is to avoid being in deep nulls of one or more modes. Deep nulls are commonly at 25% and 50% of the room lengths. The dimensions and construction of the room (and windows, doors etc) can affect these.
- speaker height should be determined by the acoustic centre of the speaker. Make sure the speakers are oriented the way the manufacturer intended, and often when either is possible, vertical usually performs a bit better. Use good sturdy stands (concrete blocks are ideal on a budget). Equilateral triangle for the speakers and a point a foot or so behind your head. Ideally your ear and speaker height won't be at 50% of the room height. Equal lengths can pile up issues and cause very deep nulls.
- speaker positioning should not be rushed, and may take a lot of back and forth and fine tuning. Live with it a few days and then adjust if needed. Its really so important. Be aware of boundary interferece (SBIR), which will not just come from the rear wall but all surfaces. Floor bounce is almost always going to cause a sizeable dip in the bass. There are calculators online that can help you predict/identify the frequencies at which these occur.
- 1st reflections will cause the most problems. A cloud is essential really, if you can make it deep then even better. Try and avoid having too much between the speakers and your listening spot, and the stuff that does need to be there, try and keep it symmetrical. The ceiling and floor are surfaces as much as the sides and front and rear are. Treating the floor is generally going to be out of the question, but the ceiling should allow for a good amount of absorption by using space that isn't required for anything else.
- 5cm panels aren't going to do anything for low end (where the most problems are). Neither are 10cm panels. 15-20cm panels will use the space more effectively, especially if there is an air gap. Just because a product is called a bass trap, don't assume its going to do anything for bass. Most panels sold online are not very effective. As a general rule of thumb, thinner panels are more effective with higher density insulation. As you go deeper, you'll want lower density, otherwise the insulation becomes reflective at certain frequencies and can cause comb filtering. 40kg/m3 density rockwool is good all purpose stuff, for thicker panels that are really effective for bass, fluffy fibeglass is great. If you have space for 30cm or more deep panels, you'll be able to absorb some low frequencies. Limp membrane and diaphragmatic absorbers are even more effective for low frequencies, and generally speaking, pressure based bass traps are much more effective than absorbing. GIK soffits are a pretty effective off the shelf solution, aside from your ceiling cloud you can pretty much just build a fort out of these and get good results.
- porous absorbers (what most panels and corner traps are) are velocity based. Sound has 0 velocity at surfaces, so they are more effective when they are not directly on the surface. Pressure based traps are effective where pressure is highest and velocity is lowest. Triangular corner traps aren't using your space effectively as they tend to optimise the wall surfaces and have little in the areas where velocity is higher. This is why they need to be DEEP, and ideally pressure based too (idealy targeting very specific frequencies based on your own room).
- the rear wall is going to be one of the best places to treat low modal issues. If you have room, here is a good place for deep bass traps of pink fluffy insulation (and membrane traps). The reflections from this wall can cause issues too, depending on how far away it is. Once your 1st reflections are taken care of, the rear wall is the next place to focus on.
- leaving areas reflective will make the room more pleasant to be in. Making the room overly dead just makes things weird and you wont want to spend any time in the room. Any traps you do use should be effective, lots of thin panels will just absorb high frequencies and use valuable space that could tackle the problems in the low end. High frequencies are comparatively much easier to treat than low modal stuff.
- diffusers are not going to be helpful for most people. Keep them away from monitoring, they'll distort your imaging in unpredictable and unhelpful ways - they are essentially just distorting your signal. If anywhere, at the rear of the room can be OK. Typically, they only work on a narrow band of frequencies and you can get similar results by just leaving areas reflective. Worry about those when everything else is taken care of, if needed as they arent cheap, they're big and heavy and take up room for things that might actually help.
- Whilst corrective EQ software can be very helpful, it cannot do anything for the time domain in your room. Unfortunately, the time domain is what you need to treat. Once you get your time domain under control, the frequency response will largely fix itself. Automatic correction generally brute forces itself to achieve a flat response at your listening position, with no regard for anything else. This can lead to lots of narrow EQ boosts that are reducing the headroom of your speakers, and often that won't actually help the frequency response where you are sat. Try and get your decay times in your room under control first. You're also unlikely to want a ruler flat frequency response in your room. Generally we want to have a few dB more bass with things sloping down gradually as the frequency increases. Random screenshot pulled from google images, but imagine this kind of shape:
- Chasing a flat EQ response at all costs is not advisable. Pay attention to whats going on in your room, but be aware of time doman, reflections and actually listening. Some dips will change drastically with the smallest movement of your head and won't be percievable when listening to music (they'll look worse under the mic). Always go off how things sound to you, listen and verify what you hear by measuring.
- try and set up against the shortest walls in your room. Keep things as symmetrical as possible on your left and right. 1st reflections need a lot of consideration, generally its best to have the sides as your nearest walls and the rear wall further away.
- speakers almost always want to be as close to the front wall as you can get them. Be aware of rear firing ports and heat dissipation from active monitors, although the angle of the speakers often leaves enough room for those to operate properly.
- keep the entire front wall reflective. Bass radiates in all directions at low frequencies, and to absorb in any meaningful way is going to require a lot of depth. Not going to happen. If you have the speakers close to the wall, the reflections you do get will be closer in time to the sound leaving the speaker. The speakers will also have more headroom/efficiency if they don't have absorption behind them. Put your panels in areas between you and the speakers - they'll be WAY more effective treating 1st reflections.
- measure your room, and also be aware of the axial room modes. Identifying the best positions to place your speakers AND your listening position is critical. The flattest position you can find with no treatment is likely to be your best spot even with lots of treatment. Often 38% gets mentioned online as the distance from the front wall where your best spot is likely to be. A good way to test is to place a single speaker in a front corner of the room, play some music you are familiar with, and gradually move backwards and forwards down the centre of the room. You'll notice the bass response change, and where it sounds most even is likely to be a good spot to listen from. You can measure with a mic and see if the response of the modes looks even. The goal is to avoid being in deep nulls of one or more modes. Deep nulls are commonly at 25% and 50% of the room lengths. The dimensions and construction of the room (and windows, doors etc) can affect these.
- speaker height should be determined by the acoustic centre of the speaker. Make sure the speakers are oriented the way the manufacturer intended, and often when either is possible, vertical usually performs a bit better. Use good sturdy stands (concrete blocks are ideal on a budget). Equilateral triangle for the speakers and a point a foot or so behind your head. Ideally your ear and speaker height won't be at 50% of the room height. Equal lengths can pile up issues and cause very deep nulls.
- speaker positioning should not be rushed, and may take a lot of back and forth and fine tuning. Live with it a few days and then adjust if needed. Its really so important. Be aware of boundary interferece (SBIR), which will not just come from the rear wall but all surfaces. Floor bounce is almost always going to cause a sizeable dip in the bass. There are calculators online that can help you predict/identify the frequencies at which these occur.
- 1st reflections will cause the most problems. A cloud is essential really, if you can make it deep then even better. Try and avoid having too much between the speakers and your listening spot, and the stuff that does need to be there, try and keep it symmetrical. The ceiling and floor are surfaces as much as the sides and front and rear are. Treating the floor is generally going to be out of the question, but the ceiling should allow for a good amount of absorption by using space that isn't required for anything else.
- 5cm panels aren't going to do anything for low end (where the most problems are). Neither are 10cm panels. 15-20cm panels will use the space more effectively, especially if there is an air gap. Just because a product is called a bass trap, don't assume its going to do anything for bass. Most panels sold online are not very effective. As a general rule of thumb, thinner panels are more effective with higher density insulation. As you go deeper, you'll want lower density, otherwise the insulation becomes reflective at certain frequencies and can cause comb filtering. 40kg/m3 density rockwool is good all purpose stuff, for thicker panels that are really effective for bass, fluffy fibeglass is great. If you have space for 30cm or more deep panels, you'll be able to absorb some low frequencies. Limp membrane and diaphragmatic absorbers are even more effective for low frequencies, and generally speaking, pressure based bass traps are much more effective than absorbing. GIK soffits are a pretty effective off the shelf solution, aside from your ceiling cloud you can pretty much just build a fort out of these and get good results.
- porous absorbers (what most panels and corner traps are) are velocity based. Sound has 0 velocity at surfaces, so they are more effective when they are not directly on the surface. Pressure based traps are effective where pressure is highest and velocity is lowest. Triangular corner traps aren't using your space effectively as they tend to optimise the wall surfaces and have little in the areas where velocity is higher. This is why they need to be DEEP, and ideally pressure based too (idealy targeting very specific frequencies based on your own room).
- the rear wall is going to be one of the best places to treat low modal issues. If you have room, here is a good place for deep bass traps of pink fluffy insulation (and membrane traps). The reflections from this wall can cause issues too, depending on how far away it is. Once your 1st reflections are taken care of, the rear wall is the next place to focus on.
- leaving areas reflective will make the room more pleasant to be in. Making the room overly dead just makes things weird and you wont want to spend any time in the room. Any traps you do use should be effective, lots of thin panels will just absorb high frequencies and use valuable space that could tackle the problems in the low end. High frequencies are comparatively much easier to treat than low modal stuff.
- diffusers are not going to be helpful for most people. Keep them away from monitoring, they'll distort your imaging in unpredictable and unhelpful ways - they are essentially just distorting your signal. If anywhere, at the rear of the room can be OK. Typically, they only work on a narrow band of frequencies and you can get similar results by just leaving areas reflective. Worry about those when everything else is taken care of, if needed as they arent cheap, they're big and heavy and take up room for things that might actually help.
- Whilst corrective EQ software can be very helpful, it cannot do anything for the time domain in your room. Unfortunately, the time domain is what you need to treat. Once you get your time domain under control, the frequency response will largely fix itself. Automatic correction generally brute forces itself to achieve a flat response at your listening position, with no regard for anything else. This can lead to lots of narrow EQ boosts that are reducing the headroom of your speakers, and often that won't actually help the frequency response where you are sat. Try and get your decay times in your room under control first. You're also unlikely to want a ruler flat frequency response in your room. Generally we want to have a few dB more bass with things sloping down gradually as the frequency increases. Random screenshot pulled from google images, but imagine this kind of shape:
- Chasing a flat EQ response at all costs is not advisable. Pay attention to whats going on in your room, but be aware of time doman, reflections and actually listening. Some dips will change drastically with the smallest movement of your head and won't be percievable when listening to music (they'll look worse under the mic). Always go off how things sound to you, listen and verify what you hear by measuring.
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