Just trying to get some sort of an idea how far a larger OB bass driver should move in regular music use.
The reason I ask is that I have my new 18" Tc Sounds Pro 5100 (only the one) just sitting propped up on the floor.
It seems to put out a reasonable amount of sound (although currently crossed over a little high ~300Hz) but I notice the cone barely moves.
I keep reading that you need drivers with a big excursion and mine is capable of some fairly big numbers (several inches), but the cone would be lucky to be moving .5mm-1mm.
Just trying to work out what is normal for OB.
The reason I ask is that I have my new 18" Tc Sounds Pro 5100 (only the one) just sitting propped up on the floor.
It seems to put out a reasonable amount of sound (although currently crossed over a little high ~300Hz) but I notice the cone barely moves.
I keep reading that you need drivers with a big excursion and mine is capable of some fairly big numbers (several inches), but the cone would be lucky to be moving .5mm-1mm.
Just trying to work out what is normal for OB.
What's "normal" for one man is total boredom for the next and freakingly venturesome for yet another. There are easily 10 dB SPL difference between what people would consider nice loud bass under the same circumstances. And there is probably a full octave between what people would consider nice deep bass. Now compare 80 dB at 50 Hz to 90 dB at 25 Hz - excursion demand will increase more than tenfold between those two.
I take your point that bass is extremely subjective and therefore hard to define, but my question is more based around the cone movement. What I am trying to work out is what is a normal or a typical amount of movement?
What I am trying to determine from the question is... Can you go too big with a bass driver? Or can it be too beefy? For example I can use an excavator to dig a hole to put in a pot plant, or I could use a spade or shovel (depending on what you call it in your respective countries).
In OB where there isn't a lot to load the driver, can a driver be too heavy duty?
Consider this for a moment... If the cone didn't have a surround it would move more freely and therefore further in and out, if the surround was super heavy duty would it become a limiting factor in developing "deep bass" (whatever our own personal definition may be)?
What I am trying to determine from the question is... Can you go too big with a bass driver? Or can it be too beefy? For example I can use an excavator to dig a hole to put in a pot plant, or I could use a spade or shovel (depending on what you call it in your respective countries).
In OB where there isn't a lot to load the driver, can a driver be too heavy duty?
Consider this for a moment... If the cone didn't have a surround it would move more freely and therefore further in and out, if the surround was super heavy duty would it become a limiting factor in developing "deep bass" (whatever our own personal definition may be)?
Hi,
Yes, of course you can. But .... the main parameter is volume displacement.
As long as you have enough power it determines how low you can go
versus how loud you can go. Only if the driver goes lower and louder
than you really need is it wrong, but given most need a given loudness
level how can anybody not like it being able to go lower (with EQ) for
their preferred (maximum) loudness level, unless they e.g. don't have
the right amplifier power to use the driver properly with the right EQ.
rgds, sreten.
You're going to need a lot of EQ to get deep bass out of that driver in an OB.
Put a 30Hz, 12dB/oct lowpass on it. And feed it decent power. Then you'll see it move a bit!
We don't believe any of it until we see picts! Newbies....
Yea of little faith, here you go
I'm not necessarily saying I am unhappy with the amount of bass, just that I expected the cone to move more, I do realise that because the sheer size of the cone it doesn't need to move much to move a lot of air.
If I rest my fingers on the cone it barely seems to be moving, so I was wonder why does everyone chase so much Xmax when it doesn't seem to use it.
Just wondering if a lighter weight driver might do a better job...
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I don't need super low bass out of them as I plan to buy a pair of these for some sub cabinets.
LMS-Ultra 5400 18″ Driver | TC Sounds
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18" doing 20Hz sine wave:
Eminence SigmaPro18 doing 20Hz.AVI - YouTube
No other numbers. Not much power input, and absolutely not much SPL output. It's doing that very quietly, really.
On OB, it doesn't need much power (and motor) to make the woofer run out of Xmax.
http://www.linkwitzlab.com/faq.htm#Q6
Eminence SigmaPro18 doing 20Hz.AVI - YouTube
No other numbers. Not much power input, and absolutely not much SPL output. It's doing that very quietly, really.
On OB, it doesn't need much power (and motor) to make the woofer run out of Xmax.
http://www.linkwitzlab.com/faq.htm#Q6
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Here is a picture of the current xover...
Clearly you can see from the pictures the driver sitting on the floor isn't going to produce optimal bass. So not overly worried about bass output, was just curious about the excursion.
I am still trying to work out how to use the software, so what you see here is probably far from what the software is capable of, it just needs me to catch up.
Just sort of worked out how to use the notch filters. Still have lots to work out.
Clearly you can see from the pictures the driver sitting on the floor isn't going to produce optimal bass. So not overly worried about bass output, was just curious about the excursion.
I am still trying to work out how to use the software, so what you see here is probably far from what the software is capable of, it just needs me to catch up.
Just sort of worked out how to use the notch filters. Still have lots to work out.
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Also found this website which suggests I am on the right track... Designing Loudspeakers - Part 15 Open Baffles and Bass
See this is what I am trying to work out what moves the cone like that. I have that 18" hooked up to a 1000w (4ohm) per side Rotel digital amp and it is bearly moving.
So clearly it's not a lack of available power. So either I am currently not playing music in that frequency range to move the driver sufficiently, or the lack of any baffle whatsoever s making it roll off too serverly.
Time to put a test tone disk in and see what that tells me.
Yep the booklet shows two different configurations serial and parrallel have them hooked up 2 + 2 for a 4ohm output, serial produces 1ohm (which I think my amp might just protest slightly)
Just threw in the test tone disk to see what it had to tell me...
Quite suprising really:
31Hz just hear the slightest noise
40hz jumped up in SPL a fair bit but still not over the top loud
50hz very similar to 40
63hz again fairly flat
80hz, 100hz fairly even
125hz slight dip
160hz back to previous level
200hz getting louder
250hz slighly louder again
315hz loudest of all
400hz rolling off and quietening down
500hz lower still
630hz faded right out down near 40hz level
This tells me two things... firstly the level of bass I am getting out of the driver is not low compared to the dual 6.5 Revelators. Without hooking the Cremonas up I would say they are very roughly on par, and probably expains why the bass while not over the top, is still half decent.
Second thing it tells me is that Robert from Ground Sound knows how to make a crossover that works
Just threw in the test tone disk to see what it had to tell me...
Quite suprising really:
31Hz just hear the slightest noise
40hz jumped up in SPL a fair bit but still not over the top loud
50hz very similar to 40
63hz again fairly flat
80hz, 100hz fairly even
125hz slight dip
160hz back to previous level
200hz getting louder
250hz slighly louder again
315hz loudest of all
400hz rolling off and quietening down
500hz lower still
630hz faded right out down near 40hz level
This tells me two things... firstly the level of bass I am getting out of the driver is not low compared to the dual 6.5 Revelators. Without hooking the Cremonas up I would say they are very roughly on par, and probably expains why the bass while not over the top, is still half decent.
Second thing it tells me is that Robert from Ground Sound knows how to make a crossover that works
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Thx for the picts. So, once you get some baffles worked up and some measurements in hand, then we throw some low shelving EQ at it and you'll see some movement. You need to start collection some good bass tracks in the mean time. Find some nice upright bass to test for tonality and pitch definition and then some ridiculous electronica for some brown note stuff.
Also, find Maxwell's Embrya. There is some good, baby makin' bass on that disc. Very clean and well recorded and very dynamic for modern R&B/Soul.
Greg
Also, find Maxwell's Embrya. There is some good, baby makin' bass on that disc. Very clean and well recorded and very dynamic for modern R&B/Soul.
Greg
Hey Greg I have Ghetto of my Mind by Ricki Lee Jones which is supposed to be a bass buster.
Well to be semi scientific I just mapped the frequency response using something other than my ear...
Must say it doesn't look too shabby at all. Going to remove the notch filter and try it again with just a straight up crossover (will also tell me if my playing / testing actually did anything).
Well to be semi scientific I just mapped the frequency response using something other than my ear...
Must say it doesn't look too shabby at all. Going to remove the notch filter and try it again with just a straight up crossover (will also tell me if my playing / testing actually did anything).
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And here is one with just a basic crossover.
Note that from 50hz to 200hz it kept coming up with a message saying turn down the mike gain (which was already all the way down) I did it at the same volume as before, for a back to back comparison, I dont know if the software auto limited the results at all.
Kind of drifted off topic from my original question but it would seem you can still produce the numbers to a large degree with the cone barely moving.
Note that from 50hz to 200hz it kept coming up with a message saying turn down the mike gain (which was already all the way down) I did it at the same volume as before, for a back to back comparison, I dont know if the software auto limited the results at all.
Kind of drifted off topic from my original question but it would seem you can still produce the numbers to a large degree with the cone barely moving.
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