one more thing before I leave (I need to work now), when you say croosover frequency, you should remember that slope is important too, if you cross it as high as 150-160Hz, you should use steep slope, 24dB/oct or so, if shalow slope is used, then you may have localization issues (but not with two subs right under the satelites)
Absolutely right, as 45 yrs experience with a single bass channel (24 dB/octave crossover around 140 Hz) in many rooms and set-ups (including bass speaker close to one of my ears) has shown me*. However, there might be certain lab set-ups and special test signals that can be localized below that frequency... but not worth worrying about.
Many good reasons (esp in days of vinyl records) to have a single bass channel and that goes for organ music too (of which I have a lot of recordings). Also, the higher you can make that crossover, the better the sound from the mid-range units. And the mid-range units can be quite small with a high crossover. Yet more wonderful, with a high enough mid-range crossover, the easier it is to use electrostats. (My electrostats go down just fine to 70 Hz.)
However, in past few years, I have become convinced that two or more bass speakers - with the same signal - dramatically combats room and woofer placement issues. That leads me to advocate "heterogeneous" woofers, different from one another in all ways possible... but playing the same signal.
Ben
*most of that experience is with a Klipschorn bass which incidentally also hides various artefactual sounds (making it out from the amp) deep inside; but for a very quiet system and sharp crossover, no problem having a high crossover
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Hi,
It seems that we agree that sub-bass is restricted to the lowest 1-2octaves, wether that be 16-64Hz or 20-40Hz. A speaker covering that range may be called sub-woofer. Anything higher in frequency and it may not be a sub-woofer , but a woofer. This thread is not about a meaningless race for highest xover, but about dipole subwoofer. As a dipole can't exite/pressurize the room below its lowest mode, it has in theory no output at all. Only its non-theoretical behaviour in a practical room or nearfield listening allows for a bit of output at these low frequencies. To get useful output one must either stay in the subs nearfield region or/and use huge membrane areas and long excursions.
Matters change when the frequency range rises. Then output rises and even surpasses that of boxed woofers. The transition region depending on room dimensions and typically occuring between 40-60Hz.
jauu
Calvin
It seems that we agree that sub-bass is restricted to the lowest 1-2octaves, wether that be 16-64Hz or 20-40Hz. A speaker covering that range may be called sub-woofer. Anything higher in frequency and it may not be a sub-woofer , but a woofer. This thread is not about a meaningless race for highest xover, but about dipole subwoofer. As a dipole can't exite/pressurize the room below its lowest mode, it has in theory no output at all. Only its non-theoretical behaviour in a practical room or nearfield listening allows for a bit of output at these low frequencies. To get useful output one must either stay in the subs nearfield region or/and use huge membrane areas and long excursions.
Matters change when the frequency range rises. Then output rises and even surpasses that of boxed woofers. The transition region depending on room dimensions and typically occuring between 40-60Hz.
jauu
Calvin
I've experimented with crossover frequencies and subs that are placed sometimes a good deal away from mains. While it's usually nearly impossible to tell that the bass isn't coming from the main speakers (my goal, usually).
IMO, it depends on source material. With crossover points over 100 cycles, I tend to start noticing the subwoofer(s) but it depends on source material mainly. If you play something that has lots of information all over that area of the spectrum, it's easier to locate for me. But, if you play jazz/blues or "girl with a guitar" type stuff, it gets harder to localize.
I think if your crossover point is set any higher than 70 or 80 cycles, eventually you'll hear a song or a note and be like "yeah, there it is."
I have found that I really prefer to cross over subs low, like 60 Hz low.
This allows the use of lower order (12 dB) LP filters on the subs which I feel improves SQ due to less phase issues.
But, this also requires that I have conventional woofer boxes (2 of them to provide sound localization cues) that have HP24 @ 30 Hz and cross to the mids at where ever I need to, like 180 to 200 Hz.
This really unloads the mid-woofers.
.
Many roads to the one goal.
Dave
This allows the use of lower order (12 dB) LP filters on the subs which I feel improves SQ due to less phase issues.
But, this also requires that I have conventional woofer boxes (2 of them to provide sound localization cues) that have HP24 @ 30 Hz and cross to the mids at where ever I need to, like 180 to 200 Hz.
This really unloads the mid-woofers.
.
Many roads to the one goal.
Dave
While this is not the time to dispute the Religion of Crossovers, I think if you did the math, you'd readily conclude that that there is no place you could crossover at 12dB/octave any where north of 40 Hz and keep localizable sounds out of your sub even "masked" with the music that it is playing.
But at 24 dB you can.
Speaking of firm convictions, I think for serious installations at home, makes clear sense to go multi-amp today.
Ben
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DOH.. DISREGARD
I have the DCX set at BW24 @ 70 Hz
Sorry,
Do, Do Do talking out my backdoor.
You think so?
You are probably right.
.
I have an old scope across one of the sub amp channels (speaker wires-10X probe).
I do see allot of higher frequency stuff but it's amplitude is pretty small at less than 1 division on the scope screen compared to when I hear the subs kick in and look at the scope and see 20-30Hz at the full height of the scope screen at 8 divisions, or often way off of the scope. (I guess full output is about 10 divisions high)
Thanks,
Dave
Oh and yes, multiple amps and EQ and Xover processing in the digital domain, if yer serious.
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Do the math. Scopes are real poor at informing anybody about what can be heard.
Speaking of religion-like convictions, this forum is ordinarily free of golden-ear arguments about who can hear better than who. Let's keep it that way (even if I have veered into that mud myself).
B.
1division of a scope display is only -18.6dB ref 8 divisons.
A 24dB/oct filter set at 70Hz will be ~21dB down @ 140Hz.
-18.6dB will occur around 120 to 130Hz.
Not much discrimation between in passband and out of passband using a scope.
A log scale real time FFT can show this discrimation very well.
A 24dB/oct filter set at 70Hz will be ~21dB down @ 140Hz.
-18.6dB will occur around 120 to 130Hz.
Not much discrimation between in passband and out of passband using a scope.
A log scale real time FFT can show this discrimation very well.
My H-baffles are 600x600 mm in footprint, with 1120 mm height. Like a small refrigerator you might say... and I have eight of them, each with twin 21" long-throw drivers.
Even so - to call them subwoofers is not quite right, as they simply cannot play 20 Hz with little audible distortion, and I run them all the way up to 200 Hz...
anybody know how does it works?Never seen this type of subwoofer in the textbook before:
If I'm not mistaking, those woofers are 15". With no baffle I'd expect the distortion will go through the roof below some 50-ish Hz. Not much quality bass to expect there I guess.
So I am interpreting mixed signals (no pun intended) here.
I have my main woofer boxes in 2 corners with the mids, tops mounted on the woofer boxes.
The woofer boxes are high passed at BW24_30Hz
.
Then I have the subs in other places (they seem to move often) in the room and like to sit together (They get louder and lower
).
Disregarding delays, which I have been playing around with, should I use a higher order LP filter on the subs or maybe go down in the filter F3?
.
I started out using BW48 filters everywhere but it seemed to sound better every time I went lower on filter slope.
Could this just be because I am filling in more places with multiple speakers by using lower filter slopes?
.
I usually can not discern location of the subs unless they are close to where I am sitting and the sub signal seems to be coming from the main woofer boxes most of the time.
I presume that part of this is because the main woofers go down almost as low as the subs and have a strongly rising response down to 35 Hz after which they drop like a rock.
.
I see your point about the scope, 1/10 of the voltage is not all that much lower.
I may have not exactly painted the correct picture.
There is always 6 to 10 cycles apparent on the scope, but maybe it is only 1/4 division high.(scope is set 5 mS/div or 20Hz = one full wave on screen).
But that means 10 cycles on scope is 200Hz, and I can see it even if it is low amplitude.
I guess it is really up to me to decide at what point the higher content becomes apparent to me.
.
But, what slopes would all of you recommend?
Thank you everyone for your opinion and knowledge.
.
And sorry for the long post.
Dave
I have my main woofer boxes in 2 corners with the mids, tops mounted on the woofer boxes.
The woofer boxes are high passed at BW24_30Hz
.
Then I have the subs in other places (they seem to move often) in the room and like to sit together (They get louder and lower
).Disregarding delays, which I have been playing around with, should I use a higher order LP filter on the subs or maybe go down in the filter F3?
.
I started out using BW48 filters everywhere but it seemed to sound better every time I went lower on filter slope.
Could this just be because I am filling in more places with multiple speakers by using lower filter slopes?
.
I usually can not discern location of the subs unless they are close to where I am sitting and the sub signal seems to be coming from the main woofer boxes most of the time.
I presume that part of this is because the main woofers go down almost as low as the subs and have a strongly rising response down to 35 Hz after which they drop like a rock.
.
I see your point about the scope, 1/10 of the voltage is not all that much lower.
I may have not exactly painted the correct picture.
There is always 6 to 10 cycles apparent on the scope, but maybe it is only 1/4 division high.(scope is set 5 mS/div or 20Hz = one full wave on screen).
But that means 10 cycles on scope is 200Hz, and I can see it even if it is low amplitude.
I guess it is really up to me to decide at what point the higher content becomes apparent to me.
.
But, what slopes would all of you recommend?
Thank you everyone for your opinion and knowledge.
.
And sorry for the long post.
Dave
Kyron Gaia specs: Specifications
Tour de force? What's the point of having 6 woofers instead of 3 per speaker (high spl?
Has anyone seen measurements, horizontal dispersion?
..but I like the mtm upper section
-
Kyron Audio Gaia Dipole Loudspeaker System
Tour de force? What's the point of having 6 woofers instead of 3 per speaker (high spl?
Has anyone seen measurements, horizontal dispersion?
..but I like the mtm upper section
-
Kyron Audio Gaia Dipole Loudspeaker System
- Loudspeaker Type
- 3 Way, DSP Controlled Active Dipole Loudspeaker System
- Frequency Response Range
- 20Hz to 30KHz
- Polar Response Pattern
- Figure 8 response
- Tweeter
- 4x 1 inch ring radiator with patented symmetrical drive motor
- Midrange
- 4x 7 inch neodymium dipole mid-woofer
- Woofer
- 12x 12 inch dipole long throw woofer
- Preamplifier
- Inputs S/PDIF, AES/EBU, Balanced XLR, Unbalanced Eichmann RCA
- 6x Digitally controlled analogue volume control
- Digital Signal Processing by DEQX™
- High Definition Speaker Correction
- Linear Phase Crossovers
- Advanced Room Measurement and Correction
- Amplification
- High - 2x 200 Watt amplifiers
- Mids - 2x 500 Watt amplifiers
- Subs - 4x 250 Watt amplifiers
- Total amplifier capability including headroom - 5000 Watts RMS
ShadyDave - Andrew has a good point (as you later acknowledged in a very nice post). But an equally dramatic factor not revealed by scopes is the human hearing curve. Your detection is vastly more sensitive to just a small wisp of midrange sound "leaking" into a low-range driver. THAT small wisp of sound leaking due to a shallow-rate crossover is easy for your brain to localize.
I would add, perhaps less diplomatically, that it is easy to confuse visual and language descriptions for hearing phenomena. What to your eye looks like a "sharp" cut-off, "gotta" sound disruptive too, eh. BTW, that is one reason certain golden-ear people are HORRIFIED over the sound of comb filtering (related to driver placement), while the rest of us can't hear any problem (even in labs).
Ben
I think 80hz is fine for a single (well placed, well built) Subwoofer with a good drive unit and a well integrated crossover. If you are hearing the location of the Sub with a crossover set to 80hz I expect the sub is really contributing significant output well above this frequency.
I use a stereo pair of sealed box Sub's with Linkwitz Pluto 2.1. The system is called Linkwitz Pluto Plus. This uses a crossover of 100hz per Sub channel, the speakers stand together, midrange less than 2ft from the bass cone.
I have been using this for a long time now. The system is completely seamlessly integrated. I have never once been able to locate the Sub with any kind of music or movie material at any volume level.
The sound integrates perfectly with acoustic or electronic music, only the depth of the soundstage is improved as is midrange clarity.
I also like subaru, I have a forester XTi (my name for uptuned XT) and an Impreza.
However, 160 is too high. Distortion components will be well within our localization range, and possibly high enough to excite cone breakups. With a room in modal region and a perfect, distortion free sub with very steep filters, it might be extremely difficult or even impossible to localize the sub.
In a real-world install, the 3rd harmonic at 480 will be REALLY easy to localize, and could even excite the cone breakup for some larger assemblies. Remember that filters don't cancel distortion components generated from the speaker assembly.
Remember also that testing something is different than listening. You might not be able to say "sub there" with just the sub playing crossed at 160, but might experience a shifted soundstage from the localized components from the sub during normal listening.
My original comment about Subaru has nothing to do with the brand but rather a comment on the people who drive them. Perhaps the phenomenon is localised to down under where it seems every Subaru driver has ten times more bass than he or she needs and has no mid or upper.
It is common to see one drive bye and only hear doof doof doof.
It is common to see one drive bye and only hear doof doof doof.
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While I do like AndrewT's notion of specifically defining different classes of bass, SpinMonster raises an excellent point. A sub woofer in its truest form is a driver below the woofer, and as he rightly points out is not a fixed frequency. In the same way all Holdens are cars, but not all cars are Holdens. All subs are woofers, but not all woofers are subs.
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