toning down highrange

[damianl]

Just say i have a speaker that goes from 200hz to 20k (fairly flat) and the bass from 200hz to 80hz is only -4db, can i use some sort of a crossover to "tone down" the 200hz-20k range at a level of -4db.
This would give me a response of 80hz to 20k. I dont care about sensitivity.

What about L pads can i get them to cover such a range?


thanks

[Geek]

Hi,

Seems to me a 10 ohm resistor in series with your crossover for your widerange (you'll need one in their anyway) ought to do about that

[damianl]

sorry i didn't mention it is one full range driver...its a tang band w3-593sf.
im trying to boost its bass by lowering its high range. im still fairly new to this but wouldn't the resistor you just mentioned be for a 2 or 3 way system to lower the db of the mid/highrange drivers

[planet10]

With a crossover that low you sohould be considering going active.

dave

[Cloth Ears]

Originally posted by damianl
Just say i have a speaker that goes from 200hz to 20k (fairly flat) and the bass from 200hz to 80hz is only -4db, can i use some sort of a crossover to "tone down" the 200hz-20k range at a level of -4db.
This would give me a response of 80hz to 20k. I dont care about sensitivity.

What about L pads can i get them to cover such a range?


thanks

Sooo, what your saying is that you have a speaker that goes from 80Hz to 20kHz? But that it is down 4dB at 80Hz? Is the roll-off smooth from 200Hz down to 80Hz, or is there a definite step down at 200Hz and it's relatively flat the next octave and a bit down?

Or am I swinging the wrong end of the cat?

You might be able to make do with a R||L||C filter if it's a smooth roll-off from 200Hz down to 80Hz, otherwise I think you might be stuck with only using 200Hz up (or even higher as the big step will affect the crossover anyway).

[damianl]

the rolloff from 200 to 80hz is quite smooth. Is it worth just sticking to an equalizer to do this job? or is what im saying actually quite possible?

[Cloth Ears]

Originally posted by damianl
the rolloff from 200 to 80hz is quite smooth. Is it worth just sticking to an equalizer to do this job? or is what im saying actually quite possible?

It's a bit hard (and expensive) to try to do it with passive components. Much easier (and possibly better sounding as it won't steal as much power as a passive set-up) would be to use a parametric equaliser between your pre-amp and amplifier to boost the signal from 80-200Hz. Behringer makes some cheap non-digital mono ones (PEQ2200) and some not quite so cheap stereo digital ones (FBQ-something). And then there's Rane and other people who make better ones. Passive would probably cause the sound to end up too muddy that low in the spectrum.

Neither way will be really good unless you get lucky with a great balance of EQ/amp/driver. I'd really start looking for solutions such as having your speaker run full-range , but un-aided - and then look for a set-up (2 bass drivers) to fill in the missing pieces. As you mains already have a 6dB/octave rolloff, you only need to work on a LP filter for your bass at the same slope at about 80-100Hz. So it wouldn't be a subwoofer, just a woofer.

[sreten]

Hi,

you are describing a fairly bog standard baffle step compensation
circuit, but i find it highly unlikely your speaker is flat 200Hz to 20KHz.

Read up on Baffle Step.

See the BS circuit here, you probably need something similar :

http://www.zaphaudio.com/audio-speaker18.html

/sreten.

[damianl]

not exactly fully flat but there in only about 1db difference between 20k-200hz then a smooth rolloff

[el`Ol]

In principle it works that way:
http://www.visaton.de/de/bauvorschla...anleitung.html
But the 200 Hz are too close to the impedance peak of the TB, so you would have to tame the peak with a series notch filter first.