Not as much bass at high vols

phil2009

Established Member
Ive noticed this with other sound systems Ive had in the passed, at high vol level the speakers out perform the sub, why is this?? Sound sys in sig, room size is 3-4mtrs square with concreat floor

dscf0006rc.jpg
 

HiFiRuss71

Distinguished Member
Because high SPLs at low frequencies require shifting a lot of air.

With a small sub, you run up against the limits of how far the driver can physically move (regardless of power) at very low frequencies, long before you reach the same limit higher up the frequency range, so the louder the volume goes the less deep notes it produces comparatively.

You can take steps to give the sub a hand by corner loading it for maximum boundary gain (stick it where the bin is), but at the end of the day, physics win.

Russell
 

phil2009

Established Member
Because high SPLs at low frequencies require shifting a lot of air.

With a small sub, you run up against the limits of how far the driver can physically move (regardless of power) at very low frequencies, long before you reach the same limit higher up the frequency range, so the louder the volume goes the less deep notes it produces comparatively.

You can take steps to give the sub a hand by corner loading it for maximum boundary gain (stick it where the bin is), but at the end of the day, physics win.

Russell


So I need a bigger sub if I want to fix this prob? I would of thought there would of been plenty of power left in the sub while maxing out my speakers, thats why I didnt go for the gemini. Dam looks like I got that theory wrong:mad:

I have the sub in the left corner of my room, and my levels on the the sub are these and crossover set to 90hz. As you can see the gain isnt very high, cos Ive spent about 6weeks fine tuning the sub, so bass sounds slightly louder then the speakers to make it a fuller and warmer sound. But this goes out of the window at high volume.

dscf1137p.jpg
 
Last edited:

Nimby

Distinguished Member
Conversely, with a powerful subwoofer, the bass can become overpowering at higher levels. This is due to the relative insensitivity of human hearing at low frequencies and low listening levels. As loudness increases the ear doesn't require so much boost at the lower frequencies to be heard clearly. The graphs of ear sensitivity against frequency and level are called The Equal Loudness Curves. (or Contours) Old age and damage to hearing due to high level noise exposure will usually affect the shapes of these curves.
 

HiFiRuss71

Distinguished Member
I thought they were called Fletcher Munson curves? Nimby makes a good point, although I think it is more likely to happen at higher levels than an XLS-200 will achieve.

Peak output of an XLS-200 is about 89dB @20Hz and trying to advance it further will just resort in more harmonic distortion which is of course starts at frequencies double the fundamental. By comaprrison a Monolith will do 99dB at 20Hz, but still only manage the same 105dB above 50Hz where both have enough power and cone area to shift enough air and indeed the XLS-200 is actually cleaner.

Russell
 

Member 639844

Former Advertiser
I think it ultimately comes down to the fact your just need oodles of power to get the same perceived bass in relation to the speakers at high levels. Your ears hear high frequencies better so its easier for systems to nail you with these, while subs struggle to keep this pace when going very loud, especially smaller, simpler, dare I say it, cheaper, subs. Some of this is also down to older ears too as Nimby and Russell say.

Your problem isnt really unexpected, its hard for subs to keep up with speakers because low bass is so much harder to produce than high notes. This is why subs where invented in the first place, because normal size speakers just cant do the job. The limitation your experiencing is a natural one you can only cure with a bigger (or much more expensive) sub.

Unfortunately, unless you own a IB it seems, you always have to accept a limit somewhere.
 

phil2009

Established Member
Thanks guys,, so basically live with it or get a bigger sub... I think I will have to live with it, cos Ive only had the sub for about 3months.. But im guessing if I get a bigger sub, I will have the same prob again when I upgrade my speakers,, so you cant really win can you, unless you go stupid and buy speakers and sub both together, but then thats mega money:(

On a curious note,,,,,Just how powerful would my sub have to be to keep up with my 5x50watt speakers, bare in mine I use all 5 speakers for music.

Im gutted my sub is lacking in power when my speakers are maxed out tho,, I thought there would of been power to spare, cos 5x50 is 250 and my sub is 275watts.:confused::mad:
 
Last edited:

Nimby

Distinguished Member
Thanks guys,, so basically live with it or get a bigger sub... I think I will have to live with it, cos Ive only had the sub for about 3months.. But im guessing if I get a bigger sub, I will have the same prob again when I upgrade my speakers,, so you cant really win can you, unless you go stupid and buy speakers and sub both together, but then thats mega money:(

On a curious note,,,,,Just how powerful would my sub have to be to keep up with my 5x50watt speakers, bare in mine I use all 5 speakers for music.

Im gutted my sub is lacking in power when my speakers are maxed out tho,, I thought there would of been power to spare, cos 5x50 is 250 and my sub is 275watts.:confused::mad:

Don't get bogged down in comparing watts. Efficiency varies considerably between different transducers amd alignments so watts mean almost nothing provided you have enough of them. Watts are cheap these days so rest assured BK has matched power to the driver's capability in its cabinet design. Doubling the watts usually only increases output by 3dB.

Think and act positively with what you have already. Try your sub in different places as Russell has helpfully suggested. You could be sitting in a null point where the bass is cancelled. Unless you have tried every possible position in your room you haven't helped your system maximise its true potential.
 

AngelEyes

Distinguished Member
Chaps, I haven't had my coffee yet and am not particularly familiar with BK subs crossovers but shouldn't the crossover on the sub be set to Max? Or is is already bypassed?

Adam
 

Nimby

Distinguished Member
I'd still try max frequency on the filter to see if it has any effect.

Can't trust these new-fangled electrickery things. :suicide:

You could add a notch on the volume, as well, to see if the sub has any more headroom.
 

Legzr1

Prominent Member
Doubling the watts usually only increases output by 3dB.

You say 'only'.

I was under the impression that a 3db increase is perceived by the ear/brain as a doubling in volume.



Phil2009,
I fear for your ears in later life if you're pushing speakers to their limits in a room that size :eek:
 

phil2009

Established Member
You say 'only'.

I was under the impression that a 3db increase is perceived by the ear/brain as a doubling in volume.



Phil2009,
I fear for your ears in later life if you're pushing speakers to their limits in a room that size :eek:

It doesnt hurt my ears as much as my z-680 pc speakers did, I only tried them at full vol once for about 20secs. But I guess thats more down to the high frequencies that the z-680 pumped out..

Im not sure if Ive had these at max vol yet tho, but amp has been at -15db tho, so far:D

Edit: having all 5 speakers going at the same time, sounds better I think, fuller sound and better sound stage.
 
Last edited:

Nimby

Distinguished Member
It doesnt hurt my ears as much as my z-680 pc speakers did, I only tried them at full vol once for about 20secs. But I guess thats more down to the high frequencies that the z-680 pumped out..

Im not sure if Ive had these at max vol yet tho, but amp has been at -15db tho, so far:D

If you don't already own an SPL meter I suggest you save up for one.
The RS SPL meter is available from BK, I think, as well as other places.
You can learn a great deal about your system from an SPL meter.
Even run REW to find out what is really going on.
Have you moved your sub to the same place as your bin was?
Why not? :nono:
:)
 

phil2009

Established Member
If you don't already own an SPL meter I suggest you save up for one.
The RS SPL meter is available from BK, I think, as well as other places.
You can learn a great deal about your system from an SPL meter.
Even run REW to find out what is really going on.

I wouldnt have a clue how to use one or what I am looking for.:lesson:

Have you moved your sub to the same place as your bin was?
Why not? :nono:
:)

the phono cable wont reach, but sub is in the opposite corner

dscf0004cm.jpg
 
Last edited:

phil2009

Established Member
Also, I dont know is this would effect the bass at high vol, but the room opens up into a lager room???


dscf0071p.jpg
 

HiFiRuss71

Distinguished Member
A fuller picture emerges.

Whilst the speakers, that you seem to wearing like headphones, radiate their output directly at you, a sub radiates in an omnidirectional pattern that gains from the room restricting the sound within to gain pressure.

If you open that room to another space, then not only does it now have to fill that extra volume and hence loose impact in the room it is in, the extra room may have resonances of it's own that can cause cancellations in the room where the sub is sat. If this latter situation exists in your room, then it does not matter how loud you turn the sub up, you will just drive the cancellations harder which still results in no bass.

Couple this with the possibilities of room mode cancellations within the sub's room in the first place and it's clear that all manner of reasons exist to experience less bass than you might have hoped for.

If you're not prepared to at least try to find a way of moving the sub around to experiment and are unwilling to buy the absolute minimum of an SPL meter which you should have for setting up the speakers anyway, then there's nothing that can really be done.

Except put a door in the hole, that is

Russell
 
Last edited by a moderator:

Member 639844

Former Advertiser
One option that may be surprisingly effective is putting the sub in the large room. Try it (go buy a longer phono cable tight wad :D), its surprising how a simple move can totally change things. Generally speaking, a room, or series of connected rooms like that can cause a serious bass suck out so your really missing the bass at the listening position.
 

phil2009

Established Member
One option that may be surprisingly effective is putting the sub in the large room. Try it (go buy a longer phono cable tight wad :D), its surprising how a simple move can totally change things. Generally speaking, a room, or series of connected rooms like that can cause a serious bass suck out so your really missing the bass at the listening position.

Actually come to think of it, I have a 5mtr cable that BK supplied with the sub. Will move the sub where my bin is and post you my findings.:thumbsup:
 

The latest video from AVForums

Amazon Fire TV Cube Gen 3 Review: Coming Soon
Subscribe to our YouTube channel

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom