Re: Are there sound differences with subs

[asere]

The specs for my current RCA sub 12inch woofer....200 watts rms, 4 ohms at 1 % thd. Crossover 50hz-200 hz variable. Frequency response 36hz-200 hz.
If I get the Velodyne model DEQ 8R which is only an 8 inch woofer with a frequency respose of 17-240hz and a low pass crossover of 40-120hz will it be more boomy than my current 12 inch sub?

[vläd]

Picking a sub from specs is identical to picking your main speakers from specs, it's not the ideal way. You should try to find a way to give it a listen prior to purchasing, or make sure you can return it in a certain time period.

BUT to answer your question, the 8-inch shouldn't be "boomier" and I would really question that 17-240hz.

[ckone180]

Not only would I question the 17hz spec, I would almost blindly say its flat out wrong.

Per their website for the DEQ-8
"The 360 Watt dynamic amplifier reaches frequencies as low as 32 Hz and up to 120 Hz"

This is the +/- 3 dbs. The 17hz is listed in the overall FR, which I have no clue what they're talking about there.

This is a better sub for the same money, IMO
http://www.amazon.com/Acoustech-H-10.../dp/B0006DNW6U

[asere]

What is the +/-3dbs? Sorry I am learning. I also looked up the specs on the link you sent me and it looks like a great buy. The frequency response is 24 and does not do less than 20 is that still ok? My current sub does 36 which is not as good as 24. Also will there be a difference with the 24 spec even at lower volumes?

[ckone180]

That's the usable numbers. Most specs are stretched. With some info, you can learn how to read in between the lines a little more. I will give you some tips here, but I will likely miss a few.

Wattage: most abused spec. you don't typically need very much, depending on room size, speaker efficiency, atc.
SPL: loudness
3 dbs: smallest change humans notice a differing loudness level
10 dbs: perceived as double the loudness
FR in Hz: this is the range a speaker can reproduce audio, look at the +/- 3dbs if given, but most manufacturers don't list this due to fudging numbers is easier

If you want a better sub than what I listed, you need to build your own or increase the price pretty substantially. Probably double the price of that one.

There is no substitute for air movement, so larger speaker drivers usually move more air. More specs are relevant here, but I don't want to confuse you.

Subs can sound differently, but really due to the way the react, as in boomy (driver moves about a bit too much), sloppy (driver not rigid enough, too heavy materials, etc), loudness (driver can't handle wattage or FR too low/high). For the most part subs sound similar if designed adequately and have close SPL measurements. To me, the most important things for a sub are accuracy (not muddy, boomy, etc) and loud enough to pressurize the room. Next for me would be FR, as when you can experience a very low frequency, there nothing better.

Good luck!

[MDRiggs]

Smallest difference we detect as a loudness difference (as opposed to something else) is about 1 dB -- depends somewhat on frequency. The significance of 3 dB is that it represents a halving or doubling of power (electrical or acoustical). The two key pieces of information for a subwoofer are its frequency response at moderate or low levels, which is what usually is quoted, and its maximum output versus frequency, which is almost never given. The thing is that a subwoofer may be capable of flat response down to 25 or 30 or whatever Hz at 70 dB SPL, but as you raise the output level the lowest frequency that it can reproduce without gross distortion will go up. So at 100 dB SPL, it might be good to about 50 Hz. (Modern powered subwoofers typically have limiters that prevent them from being overdriven at the bottom end, which is good, but the net result is a dynamic frequency response, with a higher LF rolloff point as the level increases.) Unfortunately, our hearing sensitivity drops off fairly sharply at very low frequencies, so you really need a pretty healthy output at, say, 30 Hz for it to be audible, much less impressive. Anyhow, subwoofers generally sound different because of frequency-response differences (extension, flatness across the passband, and the stuff discussed above) and, to a lesser extent, maximum low-frequency distortion. When a subwoofer sounds boomy or muddy it typically is a room problem or a consequence of a peaked response in the sub's own output. Speaker sound in general is pretty much all a matter of frequency response and radiation pattern (which is essentially frequency response versus angle).

[asere]

The specs below are for the Elemental Design brand sub. The numbers looks good but it is not an attractive sub for a family room. Wish I had pics to post here. Can someone give me their opinion on the specs? Thank you!

A2 - 300 Subwoofer
Item Status: Custom - Built to Order | Item: A2-300
List Price: $1,025.00
Your Price: $415.00
Select Foot Style (More Info): Spike - Included Hourglass - $17.50 Extra
Select Finish (More Info): Matte - Included Gloss Black + $150.00 Bamboo + $250.00 Maple + $200.00 Cherry + $200.00 Walnut + $200.00
Quantity:





Driver Size 12"
Driver Quantity 1
Driver Excursion 15.1mm
Total Driver Linear Displacement 1645.92cm³
Room Tuning 20Hz
Frequency Response (+/-3dB) 18-100Hz
Amplifier RMS Power 200W
Cabinet Type Vented
Shipping Weight 69 lbs
Internal Size 2.45ft³
External Size 3.70ft³
Width 18.00"
Height 18.00"
Depth 21.5"
Vent Size 4"
Amplifier Voltage 115V
Included Crossover Yes
Crossover Frequencies 40-160Hz
Phase Switch Yes
Line Level Input Yes
RCA Level Input Yes
Level Control Yes

[ckone180]

The eD is a better sub than all listed so far. Its a very capable sub. If you want it to look good, get the gloss black, otherwise save the $150 and go matte. Unfortunately, most better performing subs in this price range are going to be large. Its the nature of the beast. You can look at Hsu as well. There may be a good option in that range. IMO, eD and Hsu are the best value in this price range.

[CALIBER]

The specs below are for the Elemental Design brand sub. The numbers looks good but it is not an attractive sub for a family room. Wish I had pics to post here. Can someone give me their opinion on the specs? Thank you!

A2 - 300 Subwoofer
Item Status: Custom - Built to Order | Item: A2-300
List Price: $1,025.00
Your Price: $415.00
Select Foot Style (More Info): Spike - Included Hourglass - $17.50 Extra
Select Finish (More Info): Matte - Included Gloss Black + $150.00 Bamboo + $250.00 Maple + $200.00 Cherry + $200.00 Walnut + $200.00
Quantity:





Driver Size 12"
Driver Quantity 1
Driver Excursion 15.1mm
Total Driver Linear Displacement 1645.92cm³
Room Tuning 20Hz
Frequency Response (+/-3dB) 18-100Hz
Amplifier RMS Power 200W
Cabinet Type Vented
Shipping Weight 69 lbs
Internal Size 2.45ft³
External Size 3.70ft³
Width 18.00"
Height 18.00"
Depth 21.5"
Vent Size 4"
Amplifier Voltage 115V
Included Crossover Yes
Crossover Frequencies 40-160Hz
Phase Switch Yes
Line Level Input Yes
RCA Level Input Yes
Level Control Yes

Asere, that ed sub is a very good sub for the money and wouldbe the one i would go with if that was my price range.

[MovieLover74]

The sound of a sub means nothing. Subs are not designed to produce sound like your main speakers, only the LFE channel. Subs are designed to reproduce the very low frequency range that was captured during filming. Add some sound engineering and editing in post production and you have BOOM!! With that in mind, you have to ask yourself a question. How much bass do you want to feel in your chest while watching your favorite movie? Generally speaking, bigger subs produce lower bass tones and chest pounding bass. Smaller subs produce loud boom, but no chest pounding excitement. So it really is a personal decision you have to make. If you are going to purchase a sub, you need to listen to that sub when set up with a sound system. Even a crappy sound system can make the sub sound nice if you are a bass person. I would avoid that little 8in sub and invest in a nice quality, very powerful 12-15in sub. Velodyne, Martin Logan, and SVS make some of the best subs around. I have two Velodyne DEQ12R’s sitting in my front room myself. I literally can shake pictures off my walls and reproduce a man-mad earthquake.

[CALIBER]

The sound of a sub means nothing. Subs are not designed to produce sound like your main speakers, only the LFE channel. Subs are designed to reproduce the very low frequency range that was captured during filming. Add some sound engineering and editing in post production and you have BOOM!! With that in mind, you have to ask yourself a question. How much bass do you want to feel in your chest while watching your favorite movie? Generally speaking, bigger subs produce lower bass tones and chest pounding bass. Smaller subs produce loud boom, but no chest pounding excitement. So it really is a personal decision you have to make. If you are going to purchase a sub, you need to listen to that sub when set up with a sound system. Even a crappy sound system can make the sub sound nice if you are a bass person. I would avoid that little 8in sub and invest in a nice quality, very powerful 12-15in sub. Velodyne, Martin Logan, and SVS make some of the best subs around. I have two Velodyne DEQ12R’s sitting in my front room myself. I literally can shake pictures off my walls and reproduce a man-mad earthquake.

Your not trying to say the only difference in the sound of a sub is how loud and how low it plays are you? I also have to disagree that an 8 won't pound you in the chest, one listen to a b&w asw 608 will prove that to be false. Also I have a horn loaded sub I just built that utilizes an 8" driver and 125 watts for a car that is capable of 126db and goes beyond hitting you in the chest, it makes you feel like your brain is going to fall out of your head. All that said 8's don't generally accomplish this I am just saying they ARE capable of doing so. There are allot of different subs out there and they all sound different, just cause a 12" sub can take lets say 350 watts and dig down to say 20hz. doesn't mean it sounds as good as a different sub that is capable of the same thing.

Welcome to the board BTW!!!!! !!!!!!

[MDRiggs]

The sound of a sub means nothing. Subs are not designed to produce sound like your main speakers, only the LFE channel.

This is not really true. Some subwoofers have a peaked response that makes them sound boomy, for example. Moreover, in a home system the subwoofer typically reproduces bass below about 100 Hz for all channels, not just the LFE. And the range from 50 Hz to there is important in a lot of music.

[ev666il]

Moreover, in a home system the subwoofer typically reproduces bass below about 100 Hz for all channels, not just the LFE.

They were still designed for LFE, though. Crossover is an optional DSP at users' disposal but it is not mandatory and certainly not the reason why subwoofers were made in the first place. Otherwise, no audio track would feature contents below 100hz for any other channel and automatically convey all low frequencies directly to the sub But I realize I'm venturing on off-topic paths here.

[GOS]

Your not trying to say the only difference in the sound of a sub is how loud and how low it plays are you? I also have to disagree that an 8 won't pound you in the chest, one listen to a b&w asw 608 will prove that to be false. Also I have a horn loaded sub I just built that utilizes an 8" driver and 125 watts for a car that is capable of 126db and goes beyond hitting you in the chest, it makes you feel like your brain is going to fall out of your head. All that said 8's don't generally accomplish this I am just saying they ARE capable of doing so. There are allot of different subs out there and they all sound different, just cause a 12" sub can take lets say 350 watts and dig down to say 20hz. doesn't mean it sounds as good as a different sub that is capable of the same thing.

Welcome to the board BTW!!!!! !!!!!!

A sub after my heart. lmao

[MDRiggs]

They were still designed for LFE, though. Crossover is an optional DSP at users' disposal but it is not mandatory and certainly not the reason why subwoofers were made in the first place. Otherwise, no audio track would feature contents below 100hz for any other channel and automatically convey all low frequencies directly to the sub

Subwoofers existed long before there was any such thing as an LFE (or home theater), although not many people had them in those days. The idea was to allow reproduction of extremely low frequencies without recourse to impractically large main speakers -- really hear those deep organ pedal notes, etc. They became much more popular with the advent of home theater surround sound, however, as they allowed full-range sound with relatively small main speakers, especially for the surround channels. Although it is true that you could use very big speakers all around and route only the LFE to the subwoofer, this is not very practical in most cases and almost never a good idea regardless, as it is much easier to get even low-frequency response in domestically sized rooms if all the bass below about 80 to 100 Hz is reproduced by one or more properly placed subwoofers -- about the only way, really.

The LFE (low-frequency effects) channel was created to solve a particular problem in theatrical reproduction of modern, high-performance digital surround soundtracks. Or two related ones, really. Without an LFE, getting extremely loud bass effects (explosions, for example) requires recording everything else at a lower level to accommodate those occasional peaks, so everything else (dialogue, music, etc.) is running closer to the noise floor. The LFE is a separate track reproduced 10 dB louder than the main tracks specifically for the purpose of turbocharging such effects without sacrificing dynamic range in the main tracks. (This 10-dB boost is handled automatically in the bass management, so don't go cranking up your LFE gain by 10 dB!) These sounds are also in the main tracks, but at a lower level, with the LFE doing the heavy lifting to get the effect over the top, so to speak. This simultaneously satisfies the needs of theaters equipped with lesser sound systems that couldn't handle such wide dynamic range, as they can simply not use the LFE; the effects are still heard, just not so emphatically. This is why the LFE is never supposed to contain anything that is not present in the main channels as well, so that the effects don't just disappear altogether in such theaters. I believe Tom Holman originally came up with the idea for the LFE, though it may have been someone at Dolby -- don't remember for sure.

[ImRizzo]

I would love to hear this in person 6 x 10" with 4 x's 500 watt amps


http://www.hometheater.com/content/p...ub-2-subwoofer

[GOS]

wow - what a monster. That thing would surely shake the siding off my house.

I would love to hear this in person 6 x 10" with 4 x's 500 watt amps


http://www.hometheater.com/content/p...ub-2-subwoofer

[CALIBER]

Thing is gos it probably truly would!!

[ev666il]

MDRiggs: thanks for the informative read! I agree with you that in most applications crossing one's speakers over may be necessary to achieve accurate deep bass reproduction, though I don't think that's always "about the only way". Before upgrading my fronts, I measured my in-room frequency response and found my floorstanders reached 35Hz at ±3dB, which is what the manufacturer declares for them. Sure, with their limited driver size they lacked the body and presence bigger speakers could deliver but bass was never missing when playing back two-channel music. Back in the day I tried several times to use crossovers but I could never like the end result. It required more work than one would think to get the phase right, and my subwoofer still wouldn't merge with my floorstanders quite as seamlessly (and coming from a different manufacturer I guess that's kinda to be expected). Running them full range always provided more tonal consistency and articulation for me. Natheless, what I dislike the most about crossovers are the effects of digitally processing the signal: every time I turned it on, my soundstage would narrow down and treble would become less smooth and pleasant - I mean significantly so. I experienced this in my friends' theaters as well, and none of us crosses their speakers over. For the sake of clarity, I must say we all run fairly high end audio gear so I'm not saying the same would necessarily apply to all product ranges but it definitely was our case.

In general, I've grown kinda allergic to DSPs. I don't even like the concept, 'cause I always strive to hearing precisely what is on the disc, which requires the signal to be utterly untouched and unprocessed. The moment you apply any kind of digital processing to it, you're listening to something else than was intended (and it gets more detrimental to sound quality the more A/D/A conversions are required to apply it). This is also the reason why I never use active EQ, and I'd rather go passive if major in-room acustic flaws detracted from the listening experience. If there's a problem with the room, then the room should be corrected rather than the signal twisted to suit the room (I realize sometimes this is physically not possible, but I believe that'd be a minority of cases). But I digress, and I know you're probably going to disagree with me. That's all good: we're both enjoying what we have and that's all that matters, in the end. Besides, I like to share experiences and discuss different points of view

[MDRiggs]

MDRiggs: thanks for the informative read! I agree with you that in most applications crossing one's speakers over may be necessary to achieve accurate deep bass reproduction, though I don't think that's always "about the only way". Before upgrading my fronts, I measured my in-room frequency response and found my floorstanders reached 35Hz at ±3dB, which is what the manufacturer declares for them. Sure, with their limited driver size they lacked the body and presence bigger speakers could deliver but bass was never missing when playing back two-channel music. Back in the day I tried several times to use crossovers but I could never like the end result. It required more work than one would think to get the phase right, and my subwoofer still wouldn't merge with my floorstanders quite as seamlessly (and coming from a different manufacturer I guess that's kinda to be expected). Running them full range always provided more tonal consistency and articulation for me. Natheless, what I dislike the most about crossovers are the effects of digitally processing the signal: every time I turned it on, my soundstage would narrow down and treble would become less smooth and pleasant - I mean significantly so. I experienced this in my friends' theaters as well, and none of us crosses their speakers over. For the sake of clarity, I must say we all run fairly high end audio gear so I'm not saying the same would necessarily apply to all product ranges but it definitely was our case.

You were very lucky to have that kind of response from your speakers. This is usually difficult to achieve with speakers not designed for a specific room placement (corner, against wall away from side walls, in-wall), plus there is the problem at low frequencies of interference between the outputs of multiple speakers in the room. Anyway, years ago it was much easier to get away with just a pair of full-range speakers for music, since music recordings seldom had much or any content below about 50 Hz. Still true in many cases. I think you can pretty much always do better sending all bass below about 100 Hz to subwoofers, but no question this requires more effort for good results.

I would be very surprised if the problems you hear with crossovers have anything to do with DSP, which is just mathematical manipulation of a digital signal. In the case of filters, the end result is no different from what you would get with equivalent analog filters, except for some improvement in precision. You just have different numbers going into the D/A converters than you would have had otherwise. Much more likely what you are hearing are the effects of changes in frequency response in the vicinity of the crossover, which can affect overall timbre. Nonetheless, if you're convinced DSP is the culprit, a way out would be to use analog crossovers. I haven't investigated this carefully, but I expect that's what you'd find built into most powered subwoofers; most of the ones I've encountered certainly behave like analog circuits. And anything you adjust with continously variable knobs is pretty much sure to be analog. This is definitely more annoying than using what's built into the processor, but it can be done. On the other hand, if you're happy with your setup as it is, there's not much point. For me, the best sound I have ever had in my home has been with digital crossovers feeding all low bass to subwoofers.