[iamdk1091]

I need something that will flatline all sound produced under 40hz to 40hz.


My cheap speakers do not handle bass from 20-40 so is their anything I can do to set a floor at 40hz.


I want everything from 40-20000 will be played normally but anything below 40 to be outputted at 40.


The sound is running through my computer to my home theather.


Can this be done software? If not is their anything hardware I can buy and use it a 3.5mm or RCA jack?


If you cannot understand what i just wrote then.


For example if these were the tones over 5 seconds.


1sec -45hz

2sec -42hz
3sec -38hz

4sec -35hz

5sec -42hz


I'd like


1sec -45hz

2sec -42hz
3sec -40hz

4sec -40hz

5sec -42hz


An equalizer just boosts or lowers frequency bands.

A low or high pass filter just cuts off frequencies below or above its set point.


I need something else.

 

[bluesky636]

I must say that if there is such a device/program out there that does what you want, it probably makes everything sound like crap.


You would be better off buying a cheap subwoofer. Even cheap ones can do 30 Hz pretty easily.

 

[iamdk1091]

Well it does do 30hz but 40hz sounds louder

 

[bluesky636]

Good luck.

 

[tvrgeek]

You need to understand sound a lot better. There is a thing called "notes". Musicians produce these intentionally. If they want to produce a note in the 40Hz range, they do so. If they want to produce one in the 30 range, they first of all need a synthesizer or a full size pipe organ, as that is the only thing that goes that low, but they do so intentionally. Movie producers insert artificial special effects. They do so intentionally. You don't want to go shifting frequencies because you think it sounds louder.


If you do a little reading on how hearing works, you will understand that your ability to hear low frequencies diminished with frequency. This was well documented and described by Fletcher and Munson.
http://en.wikipedia.org/wiki/Fletche...3Munson_curves


When youare serious about low frequencies, you might do some reading on the DYI-speakers and subs or the subs forum.

 

[WarHorse]

right. fyi, the lowest key on a piano keyboard is 27 Hz.

 

[djmicromix]

This is crazy. Do not do this. It would sound terrible.

 

[ArthurPE]

yes, matlab

digitize the signal...do a DFT

write code to look at the freq domain, convert all

 

[Magnefied]



Quote:
Originally Posted by iamdk1091 /forum/post/18192003


I need something that will flatline all sound produced under 40hz to 40hz.


My cheap speakers do not handle bass from 20-40 so is their anything I can do to set a floor at 40hz.


I want everything from 40-20000 will be played normally but anything below 40 to be outputted at 40.


The sound is running through my computer to my home theather.


Can this be done software? If not is their anything hardware I can buy and use it a 3.5mm or RCA jack?


If you cannot understand what i just wrote then.


For example if these were the tones over 5 seconds.


1sec -45hz

2sec -42hz
3sec -38hz

4sec -35hz

5sec -42hz


I'd like


1sec -45hz

2sec -42hz
3sec -40hz

4sec -40hz

5sec -42hz


An equalizer just boosts or lowers frequency bands.

A low or high pass filter just cuts off frequencies below or above its set point.


I need something else.

What you need is a 1/3rd octave frequency aggregator. Modal Dynamics FA-G9000 is a good one for about $1,500 that includes a very useful phase manipulator.

 

[ArthurPE]



Quote:
Originally Posted by Magnefied /forum/post/18193598


What you need is a 1/3rd octave frequency aggregator. Modal Dynamics FA-G9000 is a good one for about $1,500 that includes a very useful phase manipulator.

do you get a quantum flagilator with that?

or do have to make do with a parsec vector segregator?

 

[Magnefied]



Quote:
Originally Posted by ArthurPE /forum/post/18193608


do you get a quantum flagilator with that?

or do have to make do with a parsec vector segregator?

Those are $500 options (each). The flagilator comes with a can of wax though.

 

[dookie1]



Quote:
Originally Posted by iamdk1091 /forum/post/18192003


If you cannot understand what i just wrote then...

i understand the 'what', just not the 'why'. use an LPF and call it done.

 

[iamdk1091]

Cool, i'll try matlab and see how it sounds.


If it sounds retarded I guess you guys would be right. Each has his own tho.


Does mat lab have an and (&&) operator?

Can i do a (sample.f30) function?


or do I have todo

if sample.x>30
****if sample.x

 

[flickhtguru]

You can't get great sound out of crappy speakers. (Well maybe you can but it would be more costly than just buying new speakers.)


Seriously if your into good sound and want tight loud low bass buy yourself some new speakers and get a dedicated sub as bluesky suggested. What your trying to do is just going to sound worse than letting your speakers do their thing.

 

[bluesky636]

This entire topic is probably the dumbest thing I have ever seen posted on AVS.

 

[rhcorolla]

OP,


What "cheap" speakers do you own exactly, driver sizes, amplification, etc.?


I've not used these RCA FMOD xovers personally, but know those who have w/ good success (& only $26/ pr.):

http://www.parts-express.com/wizards...=FMOD&x=15&y=5


Only downside is the 30 Hz or 50 Hz high pass choices don't quite hit your 40 Hz cut-off.

Note: These have a 12 dB slope, you could double them up for 24 dB slope, but then it sounds like that $52 could go a long ways toward a sub or better speaker mains...

 

[kgveteran]

... I woke up on the wrong planet didn't I ? Son of a @itch. I hate when that happens

 

[Gertjan]

I'm just dying to know why you would want to do this. Can you enlighten us? Is there some specific reason for this?

 

[bluesky636]



Quote:
Originally Posted by Gertjan /forum/post/18197911


I'm just dying to know why you would want to do this. Can you enlighten us? Is there some specific reason for this?

The OP couldn't be any clearer:

Quote:
Originally Posted by iamdk1091 /forum/post/18192003


My cheap speakers do not handle bass from 20-40 so is their anything I can do to set a floor at 40hz.

 

[sdurani]



Quote:
Originally Posted by iamdk1091 /forum/post/18192003


I want everything from 40-20000 will be played normally but anything below 40 to be outputted at 40.

You want something that take frequencies below 40Hz and shifts them up to 40Hz. Sort of like a limiter, except for frequency pitch instead of volume level. This way you can hear all the contents of the soundtrack, but within the limits of your speakers' frequency response.


Sound designers use pitch shifting tools when creating sound effects for movie soundtracks. Decades ago I got a demo of a helicopter sound being pitch-shifted to simulate the doppler effect (sounded like it was coming towards you and then flying away). But it was an analogue device with a variable knob. No way to set any sort of gate, below which frequencies would be pitch-shifted to a designated frequency (40Hz).


Have you tried Googling 'real time pitch shifter software'? I think most of them shift the entire program up or down within a couple octave range. You can move 20Hz content up one octave to 40Hz, but then voices (and everything else) will go up in pitch too. Don't know if there's anything that does specifically what you want (targets a particular frequency range of the program). But many of them are free downloads, so it might be worth trying some out.