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

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sdifox

No Lifer
Sep 30, 2005
99,162
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To clarify - I don't have the Z560's set up in this room now..they're bedroom computer speakers at the moment. I have no sub at all on the receiver.

I'm really tempted to just pick up something like this so I have it sooner than later (i.e. Tuesday with Prime :p), and then maybe slowly work on researching / building / etc something epic. Thoughts?

why waste money?
 

jlee

Lifer
Sep 12, 2001
48,518
223
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why waste money?

Because I can get a BIC F12 for $183 and have it here by Wednesday, rather than spending $500 and not having it together for a few weeks or a month, and then having way more sub than I need for the tiny room it's going in. :p

The thread on AVS seems positive so far...blah.
 

velillen

Platinum Member
Jul 12, 2006
2,120
1
81
Most of the people that built sonosub just grabbed some fabric and made a sock for it.

yeah ive noticed that. mostly its just build a simple "bottom" to hold the driver and lift it a bit off the ground and then the rest is the hollow tube.

At the moment im kind of more excited to build a box though. Heres a question though, what does adding insulation really accomplish? just cancle out higher frequencies? Whats the best? i can "acquire" everything from high-temp fiberglass, to polymide, to "yellow" glass. Not quite sure on the non military names.


I really need to stop looking at something im not even ready to build yet >.<
 

sdifox

No Lifer
Sep 30, 2005
99,162
17,470
126
yeah ive noticed that. mostly its just build a simple "bottom" to hold the driver and lift it a bit off the ground and then the rest is the hollow tube.

At the moment im kind of more excited to build a box though. Heres a question though, what does adding insulation really accomplish? just cancle out higher frequencies? Whats the best? i can "acquire" everything from high-temp fiberglass, to polymide, to "yellow" glass. Not quite sure on the non military names.


I really need to stop looking at something im not even ready to build yet >.<

Polyfill is used as a way to slow down waves, effectively increasing the internal volume somewhat. Only recommended if your box is too small and you have a sealed design.

Remember that the end caps have to form perfect seal with the sonotube. Thus there is usually another piece of wood (MDF really) that is very close to the internal diameter of the tube and the seal is formed that way, with a lot of caulking to help seal it.
 

sdifox

No Lifer
Sep 30, 2005
99,162
17,470
126
Because I can get a BIC F12 for $183 and have it here by Wednesday, rather than spending $500 and not having it together for a few weeks or a month, and then having way more sub than I need for the tiny room it's going in. :p

The thread on AVS seems positive so far...blah.

you don't need a sub then :p


But if you really must, yeah, go for it. CL it later I guess.
 
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jlee

Lifer
Sep 12, 2001
48,518
223
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you don't need a sub then :p


But if you really must, yeah, go for it. CL it later I guess.

Well is it realistic to expect to have a properly working sub set up and built right the first time? If I can go to home depot, buy everything I need and build it in a day or two, then drop in a speaker and amp and be good,that's one thing - but if I'm going to be stuck troubleshooting and screwing around for a month before it works right, I'm gonna be pissed and wish I had just bought something.

I'm used to dealing with cars and very rarely does anything go smoothly.. :p
 
Aug 13, 2008
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Because I can get a BIC F12 for $183 and have it here by Wednesday, rather than spending $500 and not having it together for a few weeks or a month, and then having way more sub than I need for the tiny room it's going in. :p

The thread on AVS seems positive so far...blah.

I know it isn't as good as a 15" you could build yourself, but for $183 the BIC F12 is a nice sub. It will also be plenty considering your room size. I picked one up last week from BLT (I assume thats where you'll get it).

tvsetup.jpg
bicF12.jpg


You can't quite see it in these photos but my 1611 is in that cabinet :cool:
 

jlee

Lifer
Sep 12, 2001
48,518
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Nice! I really like my 1611. How are you liking the sub for music/movies/etc? I am sure I'd be thrilled with something I built myself, but honestly if I can be 99&#37; as happy for $200-300 less, that's ok too. I have a lease 'till next August, and unless I end up moving out of state I imagine I will be here after that as well...no plans on buying my own house until I am out of New England.

I can get it from Amazon for $183.27 with free 2 day shipping or $3.99 overnight.
 
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Aug 13, 2008
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I haven't had it long, but in my limited testing its been great! My floor standers weren't as lacking in bass as your monitor 40s are but the difference in explosions and music bass is needed. IMO you'll be very happy with the F12.

No, it won't shake your apartment building, but it can get plenty loud enough to piss off the neighbors. It can't hit down to 20hz like an awesome home-built sub would, but in an apartment and on a budget compromises must be made. It will fill out the sound to full range (something you really do need) and combined with multeq calibration I think it sounds great.

The extra $300 in your pocket can also be used toward you getting those monitor 70s sooner, something to think about.
 

jlee

Lifer
Sep 12, 2001
48,518
223
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I've been reading the 40+ page thread on AVS and most people love it...overall tendency being it's great for HT and so-so (sometimes muddy) for music. I am not a huge audiophile...is it a pretty safe bet that for music it'll sound better than the Z560 sub did? I was happy with that once I turned the bass down, so if it'll be a better music sub than that I'm sure I will be happy. I'm pretty convinced that for HT it'll be more than adequate - and whenever I do upgrade, I will build a nice 15" in a sonotube or huge box. :p
 
Aug 13, 2008
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I am not a huge audiophile...is it a pretty safe bet that for music it'll sound better than the Z560 sub did?

Yes, that bet sounds pretty good. That z560 sub can't be putting out more than 50watts and its only an 8"er.

I'm pretty convinced that for HT it'll be more than adequate - and whenever I do upgrade, I will build a nice 15" in a sonotube or huge box. :p

I'd love to have a 500 watt 15" in as big an enclosure as possible, but that isn't in the cards right now for me either.
 

jlee

Lifer
Sep 12, 2001
48,518
223
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Apparently Amazon can now link with American Express reward points, so I have a BIC F12 on the way shipped overnight for $102.21. I don't think I could do much better for a hundred bucks. :)
 

electroju

Member
Jun 16, 2010
182
0
0
jlee, BIC America subwoofers might be cheap, but there are better brands. If you want to go cheap, go cheap.

Another design is the following.

(2) GR Research SW-12B
http://www.gr-research.com/index.asp?PageAction=VIEWPROD&ProdID=131

3 cubic feet sealed
300 watt BASH plate subwoofer amplifier

It will hit down to 25 Hz and the cost is about $350 with out including shipping and handling. Also with out material cost. Max SPL is 105 dB. Do not forget to add some polyfill or acoustic foam.

Another configuration with the same woofers as above, but a ported or bass reflex.

4.6 cubic feet
Tuned between 20 Hz to 25 Hz
500 watt BASH plate subwoofer amplifier

It should handle down to 20 Hz with a lot of ease even though it is being slightly over powered. The ports should be at least two 4 inch ports with a straight length between 32.677 inches (about 20 Hz) to 20.078 inches (about 25 Hz).

Yes, you can build a subwoofer and have it working right. Subwoofers are the easiest compared to building a multi-way loudspeaker. Subwoofer design can go crazy if the mind wonders. A sealed type for subwoofers are the easiest and they are 100% guarantee they will work that is close to what is predicted. Ported or bass reflex is a little harder because there is ports that have to be calculated and have to worry about Xmax. Passive radiators are a side step to making ported subwoofers, but they use a movable membrane to tune the box. A passive radiator can be another woofer with out a voice. The passive radiators are tuned with weights. Bandpass subwoofers is the hardest to build because a lot can go wrong like burn up the voice coil. Passive radiators can as hard as bandpass subwoofers when more than one passive radiator is used. Though there are exotic types like transmission line and horn loading, but the amount of simulations is slim to none.

Use wood screws, but do not use dry wall screws for subwoofers. The pressure inside a subwoofer box is a lot. Always drill pilot holes for MDF.
 

jlee

Lifer
Sep 12, 2001
48,518
223
106
jlee, BIC America subwoofers might be cheap, but there are better brands. If you want to go cheap, go cheap.

Another design is the following.

(2) GR Research SW-12B
http://www.gr-research.com/index.asp?PageAction=VIEWPROD&ProdID=131

3 cubic feet sealed
300 watt BASH plate subwoofer amplifier

It will hit down to 25 Hz and the cost is about $350 with out including shipping and handling. Also with out material cost. Max SPL is 105 dB. Do not forget to add some polyfill or acoustic foam.

Another configuration with the same woofers as above, but a ported or bass reflex.

4.6 cubic feet
Tuned between 20 Hz to 25 Hz
500 watt BASH plate subwoofer amplifier

It should handle down to 20 Hz with a lot of ease even though it is being slightly over powered. The ports should be at least two 4 inch ports with a straight length between 32.677 inches (about 20 Hz) to 20.078 inches (about 25 Hz).

Yes, you can build a subwoofer and have it working right. Subwoofers are the easiest compared to building a multi-way loudspeaker. Subwoofer design can go crazy if the mind wonders. A sealed type for subwoofers are the easiest and they are 100% guarantee they will work that is close to what is predicted. Ported or bass reflex is a little harder because there is ports that have to be calculated and have to worry about Xmax. Passive radiators are a side step to making ported subwoofers, but they use a movable membrane to tune the box. A passive radiator can be another woofer with out a voice. The passive radiators are tuned with weights. Bandpass subwoofers is the hardest to build because a lot can go wrong like burn up the voice coil. Passive radiators can as hard as bandpass subwoofers when more than one passive radiator is used. Though there are exotic types like transmission line and horn loading, but the amount of simulations is slim to none.

Use wood screws, but do not use dry wall screws for subwoofers. The pressure inside a subwoofer box is a lot. Always drill pilot holes for MDF.

Maybe I will build one over the winter - will keep my mind off the frozen wasteland outside :p

I think I'll be happy for $102 'till then, though. :)
 

sdifox

No Lifer
Sep 30, 2005
99,162
17,470
126
Well is it realistic to expect to have a properly working sub set up and built right the first time? If I can go to home depot, buy everything I need and build it in a day or two, then drop in a speaker and amp and be good,that's one thing - but if I'm going to be stuck troubleshooting and screwing around for a month before it works right, I'm gonna be pissed and wish I had just bought something.

I'm used to dealing with cars and very rarely does anything go smoothly.. :p

Cars are a lot more complicated than subs...

Important part of a sub is the math. Do your math right and you should be ok. Do not skimp on glue/caulking :awe:
 

vi edit

Elite Member
Super Moderator
Oct 28, 1999
62,484
8,345
126
Yes, you can build a subwoofer and have it working right. Subwoofers are the easiest compared to building a multi-way loudspeaker. Subwoofer design can go crazy if the mind wonders. A sealed type for subwoofers are the easiest and they are 100&#37; guarantee they will work that is close to what is predicted. Ported or bass reflex is a little harder because there is ports that have to be calculated and have to worry about Xmax. Passive radiators are a side step to making ported subwoofers, but they use a movable membrane to tune the box. A passive radiator can be another woofer with out a voice. The passive radiators are tuned with weights. Bandpass subwoofers is the hardest to build because a lot can go wrong like burn up the voice coil. Passive radiators can as hard as bandpass subwoofers when more than one passive radiator is used. Though there are exotic types like transmission line and horn loading, but the amount of simulations is slim to none.

Agreed. Sealed subs are pretty fool proof assuming you do a basic amount of research before hand. You don't even need to fiddle around with boxnotes or WinISD. You can just look at a couple builds that others have done, do a couple hand calculations and some simple cut plans on your MDF sheets. That's really about it.

You already bought so it's a moot point now, but for future reference it's not complicated. As far as putting it together if you do basic butt joints then you just glue and clamp. I wouldn't even mess around with screws. 3/4" is plenty to grab onto. That glue will be stronger than any nail or screw will be. Plus no chance of splitting your ends or having to countersink and spot afterwards if you want a clean finish.

I'm not really a sonotube fan. I just really don't like the looks. It's just personal. I can understand the appeal, cost and performance. Just don't like the appearance.
 

Aharami

Lifer
Aug 31, 2001
21,205
165
106
since we're already talking about subwoofers here, I'll just post my question here.

GR-Research has a deal going with 2 SW-12B subs and an SA-1 amp for $279. - http://www.audiocircle.com/index.php?topic=84443.0

Seems like a really good deal, but how do the SW-12B subs compare to the Dayton stuff from PE? This is going to be in my basement which is a 12x26' room. One 12" sub is probably not going to be enough. The SA-1 amp will put out 200W into 4 ohms. Will that be enough power, or should I get a more powerful amp from PE?
 

jlee

Lifer
Sep 12, 2001
48,518
223
106
Agreed. Sealed subs are pretty fool proof assuming you do a basic amount of research before hand. You don't even need to fiddle around with boxnotes or WinISD. You can just look at a couple builds that others have done, do a couple hand calculations and some simple cut plans on your MDF sheets. That's really about it.

You already bought so it's a moot point now, but for future reference it's not complicated. As far as putting it together if you do basic butt joints then you just glue and clamp. I wouldn't even mess around with screws. 3/4" is plenty to grab onto. That glue will be stronger than any nail or screw will be. Plus no chance of splitting your ends or having to countersink and spot afterwards if you want a clean finish.

I'm not really a sonotube fan. I just really don't like the looks. It's just personal. I can understand the appeal, cost and performance. Just don't like the appearance.

I still might build one over the winter -- I just really wanted something sooner than later...Monitor40's only put out so much bass, and it was getting old. :p
 

Soundmanred

Lifer
Oct 26, 2006
10,780
6
81
I still might build one over the winter -- I just really wanted something sooner than later...Monitor40's only put out so much bass, and it was getting old. :p

Or you might find that the one you ordered will be enough.
I've only got a Paradigm PW2200 and a pair of Bass Shakers in the couch and it's been enough for me for a long time.
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Agreed. Sealed subs are pretty fool proof assuming you do a basic amount of research before hand. You don't even need to fiddle around with boxnotes or WinISD. You can just look at a couple builds that others have done, do a couple hand calculations and some simple cut plans on your MDF sheets. That's really about it.

You already bought so it's a moot point now, but for future reference it's not complicated. As far as putting it together if you do basic butt joints then you just glue and clamp. I wouldn't even mess around with screws. 3/4" is plenty to grab onto. That glue will be stronger than any nail or screw will be. Plus no chance of splitting your ends or having to countersink and spot afterwards if you want a clean finish.

I'm not really a sonotube fan. I just really don't like the looks. It's just personal. I can understand the appeal, cost and performance. Just don't like the appearance.
Screws are not for strength, they're for alignment.

EDIT: To clarify, screws are what I use for alignment as they contribute little if any to the structural strength of the enclosure. I thought you might be referencing screws as I explicitly recommended them in jlee's other thread.
 
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Howard

Lifer
Oct 14, 1999
47,982
11
81
Even if doing research, the suspension sags and the performance gets lost. Sonotube are good because it provides the simplistic of design, but I am not saying they will be obsolete. Down firing and up firing loses performance because of Xmax gets lost. A speaker driver can lose about 1 to 20 mm if it is put a down firing or up firing. Losing only about 1 mm may not seem a lot, but it is a lot if trying to produce bass.
Downfiring does reduce xmax a little bit, but generally the downward sag is less than 1mm. You find me a driver that sags 20mm - was it one that you put together in your garage?
In order to produce bass, a lot of displacement is required.
True
Xmax mainly governors displacement.
False, displacement comes equally from Sd and Xmax (look at the formula for it)
FYI, it is displacement is the key for subwoofers.
How many times do you have to say it before it's our information?
A 12 inch woofer can compete against a 15 inch woofer.
Sometimes they can, SPL-wise, but the 15 will almost always sound better, all else equal.
It all matters about the Xmax.
Didn't you just say twice that it was all about the displacement?
Sure Sd matters too, but Xmax will still governor the output.
How many times are you going to contradict yourself? is it displacement or xmax that governs the output?
Sealed type of subwoofers are not designed for output. They are designed for accuracy. If you need loudness, vented or bass reflex is better. Using a Linkwitz Trransform can improve the performance of a sealed subwoofer, but still the Xmax is the limiting factor.
Sealed subs are not "designed for accuracy", they are used because they are easy to design and construct and tend to be small. A properly-designed vented sub in a room will sound just as good to 99&#37; of the population (there are some freaks out there) and provide up to 6dB extra output down low. Using a Linkwitz Transform can boost the lows of a sealed sub but it will not perform a miracle - max output is still limited by displacement (but you just said Xmax again...) and power requirements skyrocket.

The Dayton RS is designed for audio accuracy, so the subwoofers will not hit low. They have to be equalized or use multiple woofers. A better option to hit 25 Hz is use two Dayton RSS315HFA-8 in about 3 cubic feet box using a 500 watt amplifier. A Linkwitz Transform is optional. At 25 Hz the SPL is at 105 dB. Though if used one Exodus Shiva-X2 12 inch in the same box, it gives the same amount of output and the same performance. The difference is Xmax.
The Dayton RS won't hit low? I already said that the F3 of the vented build I showed to jlee was at 19Hz, are you stupid or just retarded? It'll easily do up to 110dB or more in-room with 300W.

I'll agree that the Shiva X2 has more displacement than a 15" Dayton RS, but:

The Shiva X2 is less sensitive (requiring almost twice the power to achieve the same SPL - 85dB/W vs 87dB/W)
The Shiva X2 costs $50 more
The Shiva X2 ONLY HAS 13% MORE DISPLACEMENT THAN A SINGLE 15" RS

Don't believe me?

12" Shiva displacement = Sd*Xmax = 506 cm^2 (2.6cm) = 1315.6 cm^3
15" RS displacement = 829.6 cm^2 (1.4) = 1161.4 cm^3

(1315.6-1161.4)/1161.4 * 100% = 13.3%

But wait, there's more:

dB = 20 log (1315.6/1161.4) = 1.08

This means that the total max output of the Shiva is only 1dB higher at any given frequency! You can barely listen for that difference, let alone notice it. For his purposes, a single 15" Dayton RS in a vented enclosure is far superior... and cheaper.

Then you put up some BS about bandwidth that I don't even know WTF... the worst part about all this is that innocent people take your crap at face value.
You just do not like me because I am stating facts that are true. I am trying to help while you make it worst. You need to get off your high horse.
go die kthx
 
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Howard

Lifer
Oct 14, 1999
47,982
11
81
It is not the -3 dB this and -6 dB that.
Oh no? Then what is?
There is more to subwoofer design than what howard and others have said.
Like what?
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.
What does this have to do with sub design? You can overdrive any kind of sub.
It seems horward is just car audio and not home audio.
Suck a dick.
In home audio, the cone travel should be no more than 75&#37; of its rated travel.
Why?
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.
Clarify what type of distortion a too-small internal volume will cause, and quantify the limit at which "slow response" has audible negative effects.
If you have time, I can provide you plans tailor for home audio usage.
Haha
I go for quality of the audio, so I count for THD in the design.
How do you do this?
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.
A dual-driver design with a servo amp is simpler than what now? Also, did you know that your precious Rythmik servo amps only work with one driver each?
For more output use two Rythmik Audio 15-inch drivers 8 ohm models with H600PEQ Servo amplifier in a 3.2 cubic feet.
Why are you suggesting servo builds to a guy who wanted to spend $100 for a sub? And again, you can't use two drivers with a single servo amp.
No bracing and no stuffing is required.
I have a feeling you don't even know why bracing is used.
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.
What? The whole point of opposite-firing drivers is to cancel reaction forces and reduce the vibration in the enclosure.
Just wire each woofer positive to positive and negative to negative. I am counting for woofer displacement when placed in in the box.
What does this even mean?
If you want other designs, I can come up some.
Please don't.
Actually anybody can hear 20 Hz.
Some people can. It's right at the limit of what's commonly accepted as the range of human hearing.
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.
Why are "your" designs good for apartments? Because people in apartments can't use subs because they RATTLE?
Bass can travel through objects, but it depends on the frequency.
... but you just said "bass"...
 
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electroju

Member
Jun 16, 2010
182
0
0
since we're already talking about subwoofers here, I'll just post my question here.

GR-Research has a deal going with 2 SW-12B subs and an SA-1 amp for $279. - http://www.audiocircle.com/index.php?topic=84443.0

Seems like a really good deal, but how do the SW-12B subs compare to the Dayton stuff from PE? This is going to be in my basement which is a 12x26' room. One 12" sub is probably not going to be enough. The SA-1 amp will put out 200W into 4 ohms. Will that be enough power, or should I get a more powerful amp from PE?
If you compare the GR Research SW-12B to a Dayton Audio RSS315HF-4, the differences are the cone travel, inductance, and impedance. Using two SW-12B could be used and it will displace more air than one RSS315HF-4. For fidelity, the Dayton Audio RSS315HF-4 is better because of lower inductance and the materials use for the its suspension. Though if you start comparing the Dayton Audio RSS315HF-4 to the AE Speakers AV12-H or AV12-X, the fidelity gets better and gets a little costly.
 

electroju

Member
Jun 16, 2010
182
0
0
Screws are not for strength, they're for alignment.
Glue does not hold for long. Sure can use epoxies, but speaker drivers can not be installed while it is drying. Screws are actually used for strength. If using screws at an angle, the screw is very strong. Though if using screws from an alloy, the screw is very, very strong.

Since after a statement like...

Suck a dick.

AND

go die kthx

have every right to ignore your questions and leave you being dumb because your statements are incorrect. You are the worst poster in this forum. The Internet is the same as meeting in person, so this how you treat others? If so, we do not serve your kind.