Which budget sub can do 20hz

[corElement]

Is there any budget sub that can do 20-25hz under the 20k mark?
Also, if a sub can do 20hz, does it mean it will have a higher degree of punch / air pressure change compared to a 30hz one or thats dependant on other factors?

 

[arj]

I would doubt it...it is the Sub 30Hz at 6 db or less that causes the sub costs to shoot up....

and

Also, if a sub can do 20hz, does it mean it will have a higher degree of punch / air pressure change compared to a 30hz one or thats dependant on other factors?

no SPLs and low frequency reproduction need not be related..you can have subs which do 16 Hz with as much SPL as is required (Below 50 hz sound gets more and more tactile) and some which may go only till 30 but knock ones stuffings out while it

 

[corElement]

I would doubt it...it is the Sub 30Hz at 6 db or less that causes the sub costs to shoot up....

and


no SPLs and low frequency reproduction need not be related..you can have subs which do 16 Hz with as much SPL as is required (Below 50 hz sound gets more and more tactile) and some which may go only till 30 but knock ones stuffings out while it

I see, if thats the case, is there anyway to determine this without auditioning through specs? is there a common factor involved say, maybe a 10" driver being able to produce more spl than a 5" one or something like that?

 

[arj]

I see, if thats the case, is there anyway to determine this without auditioning through specs? is there a common factor involved say, maybe a 10" driver being able to produce more spl than a 5" one or something like that?

definitely..it is all in some way a realtion between the volume of air moved (Hence the size of the Driver) and the power it is moved by ie the power of the amp.

you will need almost 4 x 5" to move the same air as a 10" one..all other factors being the same (Type of woofer,Size of enclosure, type of enclosure, siz of room, power of amp etc etc)

you can make a good sub if you go DIY BTW...it is not as tough as speaker design...and lots of knowledgeable folks in the forum who can help you out.

 

[Hari Iyer]

Is there any budget sub that can do 20-25hz under the 20k mark?
Also, if a sub can do 20hz, does it mean it will have a higher degree of punch / air pressure change compared to a 30hz one or thats dependant on other factors?

Only a TL designed sub can actually go down to 20Hz (-3 dB) (if at all) as both the sealed enclosure and the vented enclosure design have a roll-off @ 24db/Ocatave below their resonating frequency. Only a TL design have a roll-off of 6dB/octave below the enclosure resonating frequency. Also the impedance peak of the driver is more stable at the resonating frequency and there is minimum excrusion of the cone at the low frequency.

Best Regards,

Hari.

 

[micjak77]

Whats TL?????

 

[arj]

Is there any budget sub that can do 20-25hz under the 20k mark?
Also, if a sub can do 20hz, does it mean it will have a higher degree of punch / air pressure change compared to a 30hz one or thats dependant on other factors?

i really have no clue on the design..but how do sealed box RELs and MJ Acoustics go down to sub 20's with sealed box designs ?

 

[doors666]

Only a TL designed sub can actually go down to 20Hz (-3 dB) (if at all) as both the sealed enclosure and the vented enclosure design have a roll-off @ 24db/Ocatave below their resonating frequency. Only a TL design have a roll-off of 6dB/octave below the enclosure resonating frequency. Also the impedance peak of the driver is more stable at the resonating frequency and there is minimum excrusion of the cone at the low frequency.

Best Regards,

Hari.

thats not true. You can have a 12" or 15" ported driver tuned properly that can do 20hz at -3db, given a large enough cabinet size. Its practically impossible to get a sealed box to do 20hz at -3db without the room gain.

If you look for a sub that can do 20hz at -3db, there is a good chance that it will sound boomy due to room gain, which is more for lower frequencies. so at 20hz, you might get a 6db gain.

 

[corElement]

Is there anywhere where I can learn or maybe you guys can explain to me regarinding the+3 -6 db funda and minimum excursion rolloff etc.

 

[SAMUEL]

Whats TL?????

Hi,
TL stands for "Transmission Line"
A TL sub may looks like this

 

[sydneyvj]

The SVS PB-12NSD sub does +/-3dB 18Hz-200hz anechoic extension and my own in room measurement have shown that they can go down as low as 15Hz. Even their PB-10 NSD does +/-3dB 20-100 Hz. They are other subs that extend quite low. There is a tradeoff between how low the sub can extend and SPL.

 

[square_wave]

Quick answer. None !

High quality 20hz is seriously hi-end territory. Having a sub is one thing. Having a room to reproduce it is another. Involves lot of room treatment or expensive equalization.

Budget subs create a lot of distortion even if they are specified at 20hz at -3db. This is mostly inaudible if you are into movies. DIY and parametric equalization is a good way to achieve good bass.

 

[corElement]

Hmm, so what subs on a budget would you guys recommend?

 

[square_wave]

Budget ?

Expectations ?

Application ?

 

[corElement]

Just generally asking, not planning on buying but to get an idea what one can expect at the starter level - say between 13-20k ?

How do tube subs compare to all this.?

Also, I'm not sure if this is the right term or not but.. if power drives the woofercone to produce the lf and spl, is spl relatively responsible for lf production? ( Mind you I dont understand about the +3 / -6 db etc and all that yet, if anyone could explain in brief maybe that'd help me understand )

 

[square_wave]

There is no sub which can give you quality bass anywhere near 30hz in this budget. Some of the budget subs in this level are very heavily compromised in cabinet construction, quality of drivers and electronic components.

If you DIY with 30k, things will sound much better. But do not expect 20hz.

Tube subs like the JBLs used in cars ? They boom a lot. It is not true bass. Just a lot of one note boom with a lot of overhang. Good for hip hop and to attract chicks !

 

[corElement]

There is no sub which can give you quality bass anywhere near 30hz in this budget. Some of the budget subs in this level are very heavily compromised in cabinet construction, quality of drivers and electronic components.

If you DIY with 30k, things will sound much better. But do not expect 20hz.

Tube subs like the JBLs used in cars ? They boom a lot. It is not true bass. Just a lot of one note boom with a lot of overhang. Good for hip hop and to attract chicks !

I see, I agree regarding the tube subs. It's nowhere near as precise, just a lot of bouncy boom. Though- at what price bracket do you think non diy quality subs begin?

 

[arj]

I see, I agree regarding the tube amps. It's nowhere near as precise, ...?

er amps or Subs ?

 

[corElement]

er amps or Subs ?

LOL sub sub :lol:

 

[kapvin]

If you DIY with 30k, things will sound much better. But do not expect 20hz.

!

I beg to differ. you just have to remember Hoffman's iron law.. about enclosure size, spl and extension

just to give you an idea on the cheap...

JBL GT5-15 car subwoofer
110 litre internal volume box, loosely stuffed. Sealed alignment. (should result in a Qts of about 1, and an F3 of about 32hz in space).
Add room gain & wall loading (quarter space) or corner loading(1/8 space).. easy useful sound upto 20hz, with no equalisation required.

oh.. you need an amp.. try the 700w tapco juice-- all told you should easily come in under 30k and the system will play loud and low. - 100db+ at 20hz assured. (try that with any sub below 50k in the market!)

Similarly you can build a sub under 20k as well, which should will also get to 20hz F3 within a room, but may duck in below 100dB at that frequency.

there was a post in this forum about someone who used an eminence 12" driver, bass reflex alignment with a f3 of about 22hz, and a tapco 2500w amp, DIY all under 30k. looked really good!

just remember, your driver needs to mesh well with intended enclosure alignment. as for Car subs few (but not all) work well within an HT space..

If you do venture DIY, i think there are plenty of people here who would be happy to help..