How to Get Really Deep Bass?
For example, other things being equal (and each of the following may be manipulated to achieve certain gains at the expense of other performance factors), the larger the subwoofer box is in relation to the diameter of the woofer, the deeper the bass output will be. (One enthusiast I know installed a huge driver in one wall of a room in his house, using the adjoining room as the enclosure! When this is fired up, the entire house resonates. Is it any surprise that this gentleman lives alone?) Put another way, the smaller the box in relation to the driver, the less deep bass output will be. Or we can get somewhat deeper bass by reducing the driver size along with the box but sacrifice maximum loudness. How low do we need a subwoofer to go to deliver audible output? Human hearing extends to about 20 Hz, and although there are frequencies deeper than that--some huge pipe organs actually produce a fundamental tone at 16 Hz -- they are typically more felt than "heard." If you feel the vibrations in a church pew, or in the floor, you are likely feeling 16 Hz or so, but actually hearing the second harmonic at 32 Hz. To most of us, hearing a 32-Hz harmonic of a pipe organ "sounds" really low -- and it is -- but to add to its impact, a really fine subwoofer needs to add that ultra-low "felt" component, and deliver significant output in the 20-Hz region. Virtually all popular subwoofers achieve some bass output in the 20-Hz region, but they do so only through the assistance of room reinforcement and advantageous placement in the room. (And that's also how the sub's performance is measured, by advantageous placement of the measurement microphone in a area or node of bass reinforcement.) All of this works as long as the room isn't too big. In fact, many of us have experienced very deep bass in a car equipped with a good sub, because of the small volume of air in the passenger compartment. But in a larger space like a big room, true 20-Hz subwoofer output is hard to get. And it's this content that adds the enormous wow! element to movie soundtrack effects, and furthers the realism of great orchestral music. Earthquakes, train crashes and artillery all produce frequencies in the 20-Hz region, as do orchestra bass drums, pipe organs, synthesizers and even some pianos. Attempts have been made (not really successful) to reduce the subwoofer enclosure size and try to compensate by using very large amplifiers and huge magnet assemblies (to take the extra power) in order to produce deep bass extension and output. But ultimately, box-size-to-woofer-diameter rules! You can extract tones as low as 40 Hz from a small sub by putting it in a smaller room in a favorable location -- a room mode or corner (a node in a room can give you 6 dB of boost). Similarly, some available ultra-compact and expensive cube subwoofers do produce fairly low frequencies, but they have real limitations in maximum output. They simply won't play low frequencies at anything approaching real-life loudness. If the sub's output is 9 dB down (-9 dB) at 32 Hz (about half the output at 70 Hz), you would need eight times the power to correct for the 9-dB loss (you must double the power for every 3 dB of boost applied). If you started out using a 200-watt amplifier, you would have to increase that to a 1,600-watt amplifier and then lose most of those gains to the driver required to take the power! If in theory you wanted to design a sub that could truly reach the 20-Hz level with no more than a 4-dB drop in output in an anechoic environment, then the laws of physics dictate that the box must be large. There is no way around this. You would also need to incorporate an efficient amplifier because true deep bass extension requires enormous output (over 400 watts) in order to achieve sufficient loudness at these frequencies. It also must have the power to drive a large woofer and move the requisite quantities of air. This can present a problem for conventional analog amplifiers that are not very efficient (50% efficiency is common; the rest is dissipated in heat). Digital amplifier technology can lend itself to this application but the design would need to overcome the inherent problems with this type of amplifier. (At the moment, digital amplifiers are not generally used this way; more often they are implemented to reduce manufacturing costs at the expense of proper dynamic head room .) Overcoming the problem of a digital amplifier's "hard ceiling" in terms of dynamic headroom is a major challenge to amplifier designers. A conventional digital amplifier goes into immediate and severe distortion at its output limits. Given the widely varying signal levels of music and movie soundtracks, it's essential that new digital amplifier designs incorporate a means of preventing the amp from sudden distortion if a loudness peak exceeds the output limits of the amplifier. Digital amplifier design is making great strides and receiving lots of attention at the moment. Innovative approaches to solving the dynamic headroom puzzle will inevitably be forthcoming. This is a whole different topic, and your faithful writer will look at this in greater detail in a future issue, where I will present alternatives that may make digital amplification appropriate for high-quality audio applications. Why a Trumpet Sounds Like a Trumpet All notes from a musical instrument, deep bass included, are made up of a "fundamental" tone and harmonics, which occur at mathematical multiples of the fundamental tones and help give each instrument its tonal signature or identity. For example, even if different instruments--trumpet, sax, and piano--all play the same note of identical pitch and frequency, each instrument will sound quite different. This occurs because each instrument's harmonic makeup gives the instrument its distinctive sound. It's harmonics that make a sax sound like a sax and a piano like a piano. That's also why we are still able to "hear" a 16-Hz organ pedal tone, because we actually hear the 32-Hz harmonic, which is much louder than the 16-Hz fundamental. However, if our subwoofer doesn't reproduce any of the 16-Hz energy, then we won't feel as much and it won't seem as realistic. The same goes for soundtrack effects. by Alan Lofft (bio), Axiom Audio (reprinted with permission) |
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     Unregistered guest |
hi, wondering if you could assist me with my car audio, i dont seem to get the same bass response i used to get in my previous car(nissan 200sx)new car(mazda mx6)the sound systems were transferred accross from the old to the new vehicle. what could be wrong, if it is the acoustics what can i try to at least get some decent bass response. thanking you in advance satish |
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Bronze Member Username: Big_lSurrey, Surrey England Post Number: 26 Registered: Feb-04 |
hey man, ok there are many things you can do to get more bass in your car. you can try facing your subwoofer towards the rear of your boot so that the sound resonates back from the boot, i found this very good, try putting some kind of damping inside your sub box, this tricks the sub into thinking it's in a bigger box and pushes much harder. I think it may be an issue of acoustics with your new car, the MX6 has a smaller cabin the the 200sx so if you want more bass try uprading your amp to have more output. hope this helps mate. good luck |
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Silver Member Username: VindslPost Number: 129 Registered: Jul-04 |
i dont seem to get the same bass response i used to get in my previous car... the sound systems were transferred accross from the old to the new vehicle. what could be wrong... The only reason sound systems, in cars, sound as good as they do is because you're basically sitting INSIDE the speaker. When you changed cars, you effectively changed 'speakers', even though you retained the old drivers and amps, etc. |
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Unregistered guest |
I fixed a carrozeria twin 12inch sub with a bridgealble carrozeria amp tht came with it. the probrlm is disstorted bass. is there any way i can reduce this and my car is a nissan patrol the head unit is a sony 52 x 4. is there any specific way i should place the subs' and is there any way i can tune the amplifier? Pls help me cause i went to many people with htis problm and havnt been able to solve it. |
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Jeremy8888 Unregistered guest |
this site is GREAT, whoeve wrote that is a genious, think you could help with the dials on the back of car amps, hi pass, lo pass, bass equalizer and so on, what are they all for, and how can you maximize them to make the subs sound good |
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Jeremy8888 Unregistered guest |
oh and if the bigger the box the better the bass, then whats with the box formulas for cars? the boxes all seem pretty small |
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boomin'_subs Unregistered guest |
"try putting some kind of damping inside your sub box, this tricks the sub into thinking it's in a bigger box and pushes much harder." Hey, I have 2 tens in a double sealed box. I was wondering what kind of dampening I could use to make the subs push harder. Thanks!! |
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Unregistered guest |
hey i just got a new stereo and well i want some serious bass but the sub that i have at the moment is only like 16cm (7inches i think) the stereo is 450 wat what do you sugest i do (i have about $350-$400 to spend on either a bigger sub OR or to build a bigger box) please email me at saxamufone@hotmail.com if you have any suggestions |
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Anonymous |
I have a pair of rockford fossgate punch speakers for a car they are 15"inch 8 ohms each im going to make my own box and I want it to reach 20 hz of deep bass if possable how long and how wide would I have to make the box the speakers are 400 watts max each and how many watts for the amp should I use.size does not matter to me for the box because im going to put it into a older car with a lot of trunk space |
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Unregistered guest |
hey anonymous, right well if you can try and compy exactly the vibe AC twin 15" bass box they are 1 of the best designs i have never come accros a bass box or encloser that works so well go to www.vibeaudio.co.uk and look around evrything is there, you can order the turbo ports from vaurious sites if you look around. the turbo ports are the best ports around and they take the air presure and boost it out to give that ultra deep felling and atmosphere when used properly.if you have 2 400 watts subs first off all you need to see if that is rms or peak.peak is the maximum but you shouldnt rili run a sub to its peak beacuse it greatly reduces the subs life, so if you have 2 400 watt rms subs you need a 800 watt amp.hope that helped :D, sorri bit late lol.If eny1 eles has eny inquireies please email me im sure ill now or no some1 that does and not just subs eny thing turbo lag enything streetracershane_61@hotmail.co.uk |
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New member Username: HernandezFriendswood , Texas Usa Post Number: 1 Registered: Aug-05 |
i have four 12s and a 1000 watt amp and about 6 pages on how to wire my speakers in my box its self i need to know do you need high ohms or low ohms to make it hit really hard   |
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New member Username: RaydenPost Number: 1 Registered: Nov-05 |
I have 2 peavey djs5 speakers and 1 american audio (V-2000) amp. I'm trying to get some really deep bass out of them but I can't, can someone please help me.ps.. all the cables are connect correctly and also I have banana jacks but the speaker manual says to have two 1/4 phone jacks in parallel. so confused |
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New member Username: GirishPost Number: 1 Registered: May-06 |
i have got 2 6" by 9" speakers at d rear in my short car. how can i get good bass? d headset has 3 sets of frequencies HI MID n LOW so it gets confusing whether its d speaker to blame or d headset. I dunno im totally confused please help!!! send an answer to my email id envy_girish@yahoo.com PLEASE!!!! |
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New member Username: Antonyr123Post Number: 1 Registered: Aug-06 |
I own 4 15" Earthquake DBR 800 MAX Fs = 26Hz Qts = 0.7356 Vas = 5.71 cubic ft Sen = 92dB 2" polymide coil (4 ohms) 70 Oz magnet Santoprene surround and 3 SX900.4 - Kicker 4 Ch. 900 Watt Amplifiers 6x9" 3-Way 2000w x2 JUST IN BOOT LOL My 1st post so Hey  |
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New member Username: Antonyr123Post Number: 2 Registered: Aug-06 |
Well i find the more air u let in less loud bass is i have little holes all round i have prity loud they cound make u deff for 30 mins lol |
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Silver Member Username: Arande2400dB could probably d..., 4000 isnt ev... 100,000dB FU... Post Number: 120 Registered: Dec-06 |
I know that low ohms lets your amp put out more power if it can handle the ohms... Also I was wondering if a couple Good MartinLogan Descents could handle the deep bass requirements of my home theater. |
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New member Username: ElmerochevyridaPost Number: 1 Registered: Feb-07 |
I have an avalanche wit two crossfire DB3 tens under my back seat one on each side. i want to get more bass out of them without poppin them. any advice? email me at elmerochevyrida@aol.com any advice is greatly appreciated |
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Gold Member Username: Arande2Extreme SQ FTW Post Number: 1818 Registered: Dec-06 |
Well I've totally changed my mind over this time. Instead I've decided to get either a JBL 4642 or 4 18" Qs in the wall with an EP2500 powering them. |
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