How obvious is the difference between a 20hz capable subwoofer and 25hz, 30hz, etc?

[jlee]

Edit: Thanks to all who participated in this thread - I definitely have an idea of where I'm going to go once I have a good room (and no in-building neighbors) to worry about. For now, I picked up a BIC F12 for $102.21 shipped overnight from Amazon. Apparently they now let you use American Express points towards purchases, so I got $80-something off.

When I have a house, I look forward to a sonotube 15" or two!

---------------------------------------------------------

I'm still agonizing over what to do for a subwoofer (other thread). Part of me wants to spend ~$100 and pick up an 8" Dayton, or go to $125 and get a 10" Dayton and just use that until I have a reason to buy/build something with some oomph behind it.

However, I also want to have something that will give me a noticable improvement over the subwoofer on my old set of Z560's. Apparently they're 35hz (but with no advertised -3db level)..the 8" Dayton (~$90-100 shipped) goes to 40hz, 10" ($124.95) to 30hz, and 12" ($154.95 shipped) to 25hz.

Howard kindly provided diagrams with which I could assemble my own 300w 15" Dayton Reference subwoofer for ~$320 plus box materials cost, which would obviously far out-perform anything above.

For 70% movies, 20% gaming, 10% music, how big of a deal is it to have 20-25hz vs 30-35hz? I do have one downstairs neighbor, but he's gone a lot and I work nights, so there's a very good chance I won't have anyone else around to complain about noise when I do want to watch something loud.

 

[alcoholbob]

The Z-5500 is down something like 25dB at 40Hz, there are numerous youtube videos of Z-5500 spl tests.

The Dayton subs are overspeced. The graphs are no longer available on the 12" but it was down around -10db at 40Hz.

Below 35Hz is not that critical for typical listening since your ability to hear it is pretty diminished. It's more of an issue of feeling it, and I have subs that go pretty deep (-3db at 14Hz).

If you don't watch that many action movies, it's not that critical IMO, and it sounds like you are in an apartment. Subs are too much of a hassle if you don't have your own house.

 

[jlee]

I do want something - I'm not sure how far to go with it, though. I have Polk Monitor40 bookshelf speakers and they aren't exactly the masters of bass.

Action is my preference - I do live in an apartment, but there's only two units in the building and the neighbor downstairs is gone most of the time that I am home.

 

[electroju]

It is not the -3 dB this and -6 dB that. There is more to subwoofer design than what howard and others have said. There is displacement and how far the cone can travel. It is best to be under the limits for the cone travel than trying to squeeze every mm of the travel for output. It seems horward is just car audio and not home audio. In home audio, the cone travel should be no more than 75% of its rated travel. Then there is the box volume. If the volume of the box is too small, the speaker will have a lot of distortion and cause it to have slow response.

I use the spreadsheet called Unibox and I also use WinISD for woofer or subwoofer design.

If you have time, I can provide you plans tailor for home audio usage. I go for quality of the audio, so I count for THD in the design. If you want a simpler subwoofer to build, I suggest use two GR SW-12-8ohm and Rythmik Audio A370PEQ Servo amplifier in a about a 3.2 cubic feet. Put the woofers on opposite sides and wire them in phase. It will not rattle because it will not be rocking, but it will produce the sound or the bass. There is no port needed to handle down to 14 Hz. For more output use two Rythmik Audio 15-inch drivers 8 ohm models with H600PEQ Servo amplifier in a 3.2 cubic feet. For both designs, glue two 0.75 inch MDF together to achieve 1.5 inch thickness. No bracing and no stuffing is required. These plans are dual opposing subwoofers using acoustical suspension or sealed. You literally can put something on top of these subwoofers and it will shake it off. Just wire each woofer positive to positive and negative to negative. I am counting for woofer displacement when placed in in the box. If you want other designs, I can come up some.

Actually anybody can hear 20 Hz. Depending on the objects of the room, bass frequencies can vibrate them, so you can have tactile experience too. Also it depends on age and what you did during your life that will affect your hearing. You may need a louder subwoofer than other people to hear the bass. Since you live an apartment, you will have issues using traditional subwoofers. The designs that I suggest are good examples to start because it will not rattle, but it will produce the sounds. Bass can travel through objects, but it depends on the frequency.

Do not go with down firing or up firing subwoofers because they lose performance.

 

[JEDIYoda]

I have subs that go pretty deep (-3db at 8Hz).

 

[Emulex]

same as cars man - you really want to feel it? you can use those earthquake in the couch devices to get real low vibrating feelings.

 

[jlee]

It is not the -3 dB this and -6 dB that. There is more to subwoofer design than what howard and others have said. There is displacement and how far the cone can travel. It is best to be under the limits for the cone travel than trying to squeeze every mm of the travel for output. It seems horward is just car audio and not home audio. In home audio, the cone travel should be no more than 75% of its rated travel. Then there is the box volume. If the volume of the box is too small, the speaker will have a lot of distortion and cause it to have slow response.

I use the spreadsheet called Unibox and I also use WinISD for woofer or subwoofer design.

If you have time, I can provide you plans tailor for home audio usage. I go for quality of the audio, so I count for THD in the design. If you want a simpler subwoofer to build, I suggest use two GR SW-12-8ohm and Rythmik Audio A370PEQ Servo amplifier in a about a 3.2 cubic feet. Put the woofers on opposite sides and wire them in phase. It will not rattle because it will not be rocking, but it will produce the sound or the bass. There is no port needed to handle down to 14 Hz. For more output use two Rythmik Audio 15-inch drivers 8 ohm models with H600PEQ Servo amplifier in a 3.2 cubic feet. For both designs, glue two 0.75 inch MDF together to achieve 1.5 inch thickness. No bracing and no stuffing is required. These plans are dual opposing subwoofers using acoustical suspension or sealed. You literally can put something on top of these subwoofers and it will shake it off. Just wire each woofer positive to positive and negative to negative. I am counting for woofer displacement when placed in in the box. If you want other designs, I can come up some.

Actually anybody can hear 20 Hz. Depending on the objects of the room, bass frequencies can vibrate them, so you can have tactile experience too. Also it depends on age and what you did during your life that will affect your hearing. You may need a louder subwoofer than other people to hear the bass. Since you live an apartment, you will have issues using traditional subwoofers. The designs that I suggest are good examples to start because it will not rattle, but it will produce the sounds. Bass can travel through objects, but it depends on the frequency.

Do not go with down firing or up firing subwoofers because they lose performance.

$647 for speakers/driver, plus enclosure? Hmm, I could do it but I'd have to go without a subwoofer at all for a long time before I could spend that much.

 

[vi edit]

No computer speaker set is going to come even remotely close to what a true, purpose built subwoofer is capable of. For a high use of movies, I think you want a sub capable of producing 100db or more @ 25hz and up as a minimum. There's just a lot of material in that range in movies any more. And it's one thing to be able to produce it, another to do it loudly, and another yet cleanly.

I only say 25hz because getting lower than that really requires a combination of big drivers, big boxes, and a lot power. Plus there's been a bit of a trend lately in BR audio mixing where they are starting to put a LFE filter on content under 25hz. It sucks. But that's what it is.

I've got both a 12" Dayton RS in a sealed box and an MFW-15. There's only a few scenes where the Dayton 12" can't provide the same impact as the MFW. It can play them, but it's just not the same kind of physical feedback the the larger driver, and 2x larger ported box of the MFW can do.

I like the Daytons because they are well built and very low distortion. They just don't have quite the excursion and paper specs of some of the more adventurous subs from Exodus (Tempest X, Mal-X, ect) or AE.

You sound like a reasonably handy guy. Subwoofers are not hard to build. All you really need is a circular saw, jig saw, a pile of clamps, and some wood glue..a router is definitely preferred for hole cutting and rounding off.

A sheet of 3/4" MDF and you can build about anything out there short of the really big monsters like table tubas.

 

[vi edit]

A 12" dayton RS, a 250w plate amp and a 2cf enclosure will get you pretty good outputs. Thats what I have. I personally wouldn't get *too* worked up in the power ratings/handling of the subs. That 250w plate amp I use drives that 12" sub with pretty good results. I'm sure I'm missing out on a wee bit of exursion/extension/output. But I think the only way I'd notice was with a measuring device. I barely have the gain up 1/4 of the way before it starts to get out of whack with my front crossovers.

 

[vi edit]

Do not go with down firing or up firing subwoofers because they lose performance.

Right. So all those cylinder subs from SVS and all of HSU's are just going to fade away and they'd willingly keep making that design?

Just do your research on the driver. Some drivers are more susceptible to sag than others.

 

[jlee]

A 12" dayton RS, a 250w plate amp and a 2cf enclosure will get you pretty good outputs. Thats what I have. I personally wouldn't get *too* worked up in the power ratings/handling of the subs. That 250w plate amp I use drives that 12" sub with pretty good results. I'm sure I'm missing out on a wee bit of exursion/extension/output. But I think the only way I'd notice was with a measuring device. I barely have the gain up 1/4 of the way before it starts to get out of whack with my front crossovers.

So this and this? I didn't see a 250w at parts-express. My receiver has Audyssey so hopefully I can cheat and use that to help me set it up..otherwise I won't have a clue For the 2cf, do you subtract the space that the speaker takes up inside the box? Sounds like a 2cf MDF box would be pretty easy to put together...

 

[sdifox]

http://www.google.ca/images?q=sonot...tle&resnum=2&ved=0CC0QsAQwAQ&biw=1280&bih=868


http://dustin.bunnyhug.net/construction.php

 

[s44]

Right. So all those cylinder subs from SVS and all of HSU's are just going to fade away and they'd willingly keep making that design?

I don't know if you've read enough threads, but electroju is always wrong. It doesn't even bear mentioning at this point.

 

[jlee]

http://www.google.ca/images?q=sonot...tle&resnum=2&ved=0CC0QsAQwAQ&biw=1280&bih=868


http://dustin.bunnyhug.net/construction.php

Not sure I have enough vertical space for one of those, but I can try

 

[vi edit]

So this and this? I didn't see a 250w at parts-express. My receiver has Audyssey so hopefully I can cheat and use that to help me set it up..otherwise I won't have a clue For the 2cf, do you subtract the space that the speaker takes up inside the box? Sounds like a 2cf MDF box would be pretty easy to put together...

This is roughly what I followed:

http://www.diyaudio.com/forums/subw...udio-2-cu-ft-dayton-rss-12-hf-sealed-sub.html

I didn't do the same bracing...but it's a solid SOB and weighs in at over 60 pounds with 3/4" MDF. Very potent, clean little'ish sub.

Mine has a 250 watt amp. Those 240's from PE would be similar. I like O-Audio Bash stuff for amps more than PE though. 250 will easily drive that thing to pleasurable levels.

 

[jlee]

So regular 3/4" MDF (not doubled to 1.5")? What'd you use for internal bracing? I don't need something to knock pictures off the walls..but I am really missing the bottom half of all my audio. I will probably go with that setup - just need to get around to it and figure out how to put it together..might pick up some MDF and give it a shot when I have some time.

A Dayton 240w is $10 cheaper than a Bash 300w...should I just spring for the extra power, or is it really not going to benefit anything? $167 will get me an O Audio 300w..hmm.

 

[sdifox]

Not sure I have enough vertical space for one of those, but I can try

what? you have to have at least 9' ceiling


Over all height approximately 5'11"

 

[jlee]

what? you have to have at least 9' ceiling


Over all height approximately 5'11"

haha well I was planning on squeezing something behind the couch..not sure I can push it that far forward, though. I'll have to evaluate the room and see what I can move. I could probably fit it in a corner, but it wouldn't be immediately next to the main listening area..it'd be tucked a little ways back so I'm not sure how well that would work.

 

[electroju]

I don't know if you've read enough threads, but electroju is always wrong. It doesn't even bear mentioning at this point.

I am not wrong. I am right because I have doing this for a lot longer than you have.

 

[sdifox]

haha well I was planning on squeezing something behind the couch..not sure I can push it that far forward, though. I'll have to evaluate the room and see what I can move. I could probably fit it in a corner, but it wouldn't be immediately next to the main listening area..it'd be tucked a little ways back so I'm not sure how well that would work.

May work out better. Remember low frequency = long wavelength.

 

[HeXen]

google "buttkickers"
get the amp combo. provides the ooommph for less cash and no disturbing the neighbors. For the lows you can hear, any sub or HT in a box would work good enough. the buttkickers provide more thump you feel than any typical sub setup could.

 

[sdifox]

google "buttkickers"
get the amp combo. provides the ooommph for less cash and no disturbing the neighbors. For the lows you can hear, any sub or HT in a box would work good enough. the buttkickers provide more thump you feel than any typical sub setup could.

Not the same sensation at all.

 

[jlee]

I am not wrong. I am right because I have doing this for a lot longer than you have.

LOL if that's your reasoning, you can take me off the list of people that actually pay attention to what you say.

google "buttkickers"
get the amp combo. provides the ooommph for less cash and no disturbing the neighbors. For the lows you can hear, any sub or HT in a box would work good enough. the buttkickers provide more thump you feel than any typical sub setup could.

I had a HTIB years ago (Onkyo HTB-503, I think) and my Z560's did better. I played some bass track I found somewhere and there was a huge dead spot in the HTIB that sounded fine on the Z560's.

 

[electroju]

So this and this? I didn't see a 250w at parts-express. My receiver has Audyssey so hopefully I can cheat and use that to help me set it up..otherwise I won't have a clue For the 2cf, do you subtract the space that the speaker takes up inside the box? Sounds like a 2cf MDF box would be pretty easy to put together...

Using that amplifier with that woofer in a 2 cubic feet box will damage it at the peaks. About 250 watts is as far as it should go. At max using a 250 watts in a 2 cubic feet, it will output about 96 dB at 20 Hz. This better than Dolby requires is about 70 dB at 20 Hz, but it is below than THX requirements. Though you are in an apartment, so you do not have any flexibility on the output.

I strongly recommend that you go with the dual opposing configuration so the rattling does not come to an issue when you increase the loudness of the subwoofer. The rattling in apartments causes a lot of problems before the audible noise become an issue.

A lot of people do not know understand that the loudness of the surround sound setup have to be figure in while designing the subwoofer. The loudness of a 5 channel setup is around 8 dB. If speaker's sensitivity is about 89 dB, the loudness will be about 97 dB at 1 watt. Your subwoofer have to match that. There is also room gain to worry about.

Depending on your AV receiver, Audyssey may not equalize the subwoofer. I suggest do not hope that Audysssey in your AV receiver to fix what is dirty.

haha well I was planning on squeezing something behind the couch..not sure I can push it that far forward, though. I'll have to evaluate the room and see what I can move. I could probably fit it in a corner, but it wouldn't be immediately next to the main listening area..it'd be tucked a little ways back so I'm not sure how well that would work.

Placement is the key for subwoofers. Where you want to put it, may be at its worst spot. To figure out the best spot is place the subwoofer in the middle of the room. Then crawl along the walls with masking tape to mark the spots that has bass. Do this while playing audio with a lot of bass. Try not to count corners as a good spot for subwoofers because corners can make the bass seem slow or muddy. Corners are good for subwoofers that uses small woofers like a 6.5 or 8 inch. Sure big subwoofers could be used in a corner, but if they are underpowered for your setup where corners will help them to be louder.

$647 for speakers/driver, plus enclosure? Hmm, I could do it but I'd have to go without a subwoofer at all for a long time before I could spend that much.

You still have to wait for the subwoofer to break-in for the subwoofer to show its true performance. If I were building it, I would spread out the list when I would buy each component. I would buy a woofer or two and then wait until next month to buy the amplifier. The GR Research 12-inch woofers costs about $150 each. The subwoofer plate amplifier with parametric equalizer is the expensive part. You could just buy a BASH 300 watt from either Parts Express or O-Audio.

 

[electroju]

LOL if that's your reasoning, you can take me off the list of people that actually pay attention to what you say.

You have a big problem. I am trying to help, you are just laughing in my face. This is like throwing crap in may face.

I am helping by providing you are better option than what people have stated, so you can actually use a subwoofer. Using subwoofers where you live will cause you problems, so the dual opposing subwoofer is a better option. It will minimize the rattling, so you can set it a good level to watch movies.