AudioCircle
Industry Circles => Omega Speaker Systems => Topic started by: guf on 28 Jan 2018, 03:19 am
-
HO SAMs and a rythmik 12 inch sealed GR sub, near field and crossed over at 120. I think it’s sounds wonderful, balanced, and dimensional. I turned it up the other day because a friend suggested because we were listening to a 6 string bass player and he plays higher notes. I forgot about it and was wondering why I enjoyed my listening so much last night. Seems unconventional. Is his theory correct? And am I liking the movement or air and feeling at the expense of accuracy?
-
I too cross it over at 120 and enjoying the sound... It was suggested to me to try this because so little goes down there below 120 anyway.. By doing this , you lighten up the load to the amp that powers you R/L speakers (and speakers) and will allow it to perform better.. I use monitors.. Maybe towers a different story..
-
120 Hz is smack in the mid-bass range. There plenty going on below 120 Hz (2+ octaves of music). But yes, if you filter the bass out before sending the signal to the amp running your mains (HO SAM's) then it would lighten the load to that amp and your mains.
What frequency were you crossing over at previously?
Not the HO SAM's, but many smaller monitors lack mid-bass 'body' that would be solved by crossing over at 120 Hz. Depending on the geometry of your room/setup you could be alleviating room induced bass echo the room, creating a 3-source swarm (search Audio Circle for "swarm"). Another reason for preferring the higher crossover frequency could simply be the more the better effect.
-
try this... crossed over at 120, walk to your sub and feel how hard its working ? mine, not much.. a good reason why I'm letting the sub handle everything down at the 120 mark.. I don't fully understand everything that goes on in the frequency range as to where the instruments reside in but I read that the kick drums can operate between the 60-300Hz and sometimes higher and even lower.. I still hear kick drums through my monitors and with punch..
-
I have mine so to 110Hz although my mains measure down to about 70Hz. I like the extra clarity offloading the mains give.
-
....... Seems unconventional. Is his theory correct? And am I liking the movement or air and feeling at the expense of accuracy?
Why overthink it so much? :dunno:
If it sounds better to you, it is better. Does it matter why? Just enjoy whatever is the most pleasing.
PS: I high-pass my Omega Super 7 XRS at 100 hz and play my sub (Gallo CLS-10) up to 140 hz. Sounds great.....much better than running them full range sans sub, or full range w/ sub added to the bottom.
-
I recently changed my setting from 80 hz to 100 hz on my GR Research sealed sub I high-pass my Super 7s at 80 hz. The impact of my base jumped a couple of notches. :thumb:
-
I recently changed my setting from 80 hz to 100 hz on my GR Research sealed sub I high-pass my Super 7s at 80 hz. The impact of my base jumped a couple of notches. :thumb:
There is a big value to having overlap in the 80hz region. This is the region responsible for a lot of our bass perception (the fabled “chest lock”). We can also accommodate assymetric crossover slopes (such as 4th order for low pass and 1st order for high pass) that help localize the image to the mains.
-
IMO, ideal would be ~200 Hz but then they're woofers. :lol:
-
What most of us want are really helper woofers rather than true subwoofers. My Omega’s are helped out by a pair of Rythmik F8 “subwoofers” blended in at about 180hz. Stereo subwoofers make this easier, but overlapping the mains really helps as well.
-
try this... crossed over at 120, walk to your sub and feel how hard its working ? mine, not much.. a good reason why I'm letting the sub handle everything down at the 120 mark.. I don't fully understand everything that goes on in the frequency range as to where the instruments reside in but I read that the kick drums can operate between the 60-300Hz and sometimes higher and even lower.. I still hear kick drums through my monitors and with punch..
(http://www.audiocircle.com/image.php?id=175373)
-
Nice.... thanks Jazzaudio.. now I need to figure out how I can save that diagram for my wallpaper or screen saver (or whatever they call it) for my computer.. anybody looking for a test cd for bass ? find a band that uses a harp or a tuba, or BOTH.. wow.. that should be fun.. Little confused as to how the kick drum can spread across the spectrum ? is it where it changes color is where the medium is for that instrument ?
-
Nice.... thanks Jazzaudio.. now I need to figure out how I can save that diagram for my wallpaper or screen saver (or whatever they call it) for my computer.. anybody looking for a test cd for bass ? find a band that uses a harp or a tuba, or BOTH.. wow.. that should be fun.. Little confused as to how the kick drum can spread across the spectrum ? is it where it changes color is where the medium is for that instrument ?
There is no standard kick drum. They come in different sizes and can be tuned.
-
There is a big value to having overlap in the 80hz region. This is the region responsible for a lot of our bass perception (the fabled “chest lock”). We can also accommodate assymetric crossover slopes (such as 4th order for low pass and 1st order for high pass) that help localize the image to the mains.
What are you using to high pass?
-
"There is no standard kick drum. They come in different sizes and can be tuned"
thanks, I know they all don't sound the same but near the tweeter region ?
-
Yes, the initial "whack" on the drum is actually quite high in frequency, but obviously drops quickly into the resonant bass tone that bass drums are known for. Pipe organs and electronic bass are much different, in that they only produce the bass tone (no "whack"). Sorry for my unscientific explanation. I'm tired and don't feel like looking up the actual terminology for all this...though you likely understand what I'm talking about.
-
that was good RDavidson.. I'm tired too and if you used the terminology I'd have to get up and fetch the dictionary..
-
OEM,
I can't remember from where I copied this chart, but similar ones are online, and are more associated with recording/mixing sites. I love them because they remind me why I listen: music!
If I recall correctly, the entire horizontal bars are the audio frequencies produced by the instruments, with the red portion of the bars representing the fundamentals and the yellow portions the harmonics. Both affect tone, help us identify what instrument we're actually listening to, and are a function of instrument design, tuning, or both. The kick drum signature you're hearing through your monitors are the upper harmonics. Seeing (from the chart) the kick drum's harmonics start at about 500hz and represent half of the total range of the drum (up to about 8khz), it would make sense you hear it through your monitors. Or, more importantly, you should hear it!
Roscoe and JLM bring up great points about the 80hz region being responsible for a lot of our bass perception, and the 120hz being smack in the mid bass range and related to mid-bass body. If you look at the narratives near the bottom of the chart, 80hz is near the middle of the zone often subjectively associated with a sound having "body," and 120hz is in the range subjectively associated with "boom/punch." JLM points out allowing a subwoofer to carry more of the load up to 120hz (through both the subjective "body" and "boom/punch" ranges) could compensate for the lack of "body" in some monitors. The chart supports what both said 100% (not that they needed to be validated!)
Here's a interesting way of looking at the chart. It lists the kick drum's range (fundamentals and harmonics) as 50hz-8khz. If you take the midpoint of that range and follow it down to the subjective descriptions near the bottom of the chart, you'll end up between the subjective "fullness/mud" and "whack" and "tinny" sounds. Many of the frequency ranges contain both positive and negative subjective narratives. Which description actually applies depends on how the instrument should actually sound (by design or tuning), or ones personal preference. The midpoint range of the kick drum actually falls in the subjective "honk" sound...but since the kick isn't a brass or a woodwind instrument this may not apply But that midpoint includes the "fullness/mud" subjective range, but does not include the "whack" or "tinny" ranges.
However, all the descriptions fall within the total range of the kick drum. The key is the midpoint, or the balance of the instrument...as reproduced by the audio system. Perfectly reproduced, the kick drum would sound full (balanced.) But under-reproducing the lower frequencies and/or over-reproducing the upper frequencies would shift the midpoint toward the "whack" "tinny" range. Doing the opposite would shift the midpoint towards the "mud" range.
Another thing I like about the chart is how it highlights what we hear so much about: the midrange. Notice how often the transition between fundamentals and harmonics occurs in the midrange.
-
Here's a similar version of the frequency chart:
http://sineworld.com/html/basic_knowledge/freqchart.html (http://sineworld.com/html/basic_knowledge/freqchart.html)
-
Acoustically there are a number of factors to consider regarding at what frequency to crossover to a sub:
- bass capacity of the main speakers (to ensure mid-bass "body" isn't lost)
- localization of bass notes (the ubiquitous THX standard of 80 Hz)
- the Schroeder frequency of the room being used (where sound waves transition from behaving as waves to rays)
- is bass being filtered from main speakers/power amp (a concern for small amps)
Note that the Schroeder frequency is typically around 130 Hz and so an ideal solution may not be possible.
-
Thanks jMelvin...that copy is much easier to look at!!
-
When doing adjustments play piano recordings. The piano has the lowest and highest notes.
charles
-
Here's a interesting way of looking at the chart. It lists the kick drum's range (fundamentals and harmonics) as 50hz-8khz. If you take the midpoint of that range and follow it down to the subjective descriptions near the bottom of the chart, you'll end up between the subjective "fullness/mud" and "whack" and "tinny" sounds. Many of the frequency ranges contain both positive and negative subjective narratives. Which description actually applies depends on how the instrument should actually sound (by design or tuning), or ones personal preference. The midpoint range of the kick drum actually falls in the subjective "honk" sound...but since the kick isn't a brass or a woodwind instrument this may not apply But that midpoint includes the "fullness/mud" subjective range, but does not include the "whack" or "tinny" ranges.
Hmm. This has got me thinking about stuff I haven't thought about in years. Prior to buying the Omegas I have now (the Super 3S model) I've used Fried speakers for as long as I can remember, and for a while was having regular conversations with him about this stuff. He always tended to cross the woofer over at about 100Hz and I've taken that for granted for so long that it's kinda cool to have this thread pop up and get me thinking about it again.
Bud had a few rules about this woofer-to-midrange crossover that are worth mentioning in light of this conversation and the diagram that's been posted:
1. Get it as far below 650Hz (where most musical energy resides) as practical;
2. Drivers should be capable of performing well two octaves from the crossover point; and
3. Gentle slopes (I believe around 6dB/octave) are inherently more phase-linear.
Those rules — in conjunction with his ears and the drivers he had access to) led him to choose ~100Hz as the crossover point, almost always. Anecdotally, Bud talked a lot about evaluating a speaker by ear, and using very familiar instruments like the piano or the human voice as a guide. Everyone knows what those things should sound like, he argued, and a listener is instantly aware when something is "off" about the reproduction even if we can't pinpoint what's wrong.
Now look at that chart, specifically the junction between fundamentals and harmonics for the various instruments. With just four exceptions (snare, tuba, contrabassoon & piccolo) a 100Hz crossover is at least two octaves removed from that junction point for the other instruments and also corresponds to the lower limit for human voice. I don't think that's a coincidence. So there might be an argument there for avoiding a higher crossover point. Mightn't there?
-
There could be an argument there, but everyone's systems and rooms are different....and the difference between 100hz and 120hz is not huge, but also not necessarily trivial. It really depends on a case by case basis. The important take-away is that bass integration can be rather complex, moreso with main speakers that have limited bass range. Challenging, but not impossible.
-
There could be an argument there, but everyone's systems and rooms are different....and the difference between 100hz and 120hz is not huge, but also not necessarily trivial. It really depends on a case by case basis. The important take-away is that bass integration can be rather complex, moreso with main speakers that have limited bass range. Challenging, but not impossible.
You're right, of course. With this thread as the impetus, I've actually been thinking about it from a point of view opposite that of the OP. I guess guf isn't clear about whether he started at 120 and turned it up, or started at some lower point and turned it up to 120 ... did he say and I just missed it? Anyway, he got me thinking about where I set the subs to kick in. By default I set mine around 100Hz, which my subs are completely comfortable with, and then just fiddle with the level until it sounds right on a variety of music. Not very scientific, but I trust my ears to tell me what they like.
After this thread popped up, I got thinking about *why* I was at 100Hz. My Omegas operate full-range, after all (which really isn't FULL range but easing into the 40s, giving more than an octave of overlap). I started lowering the crossover point and found that right around 70Hz (with a slight nudge up in volume) kept the deep bass but cleared up a slight thickness that I hadn't realized was there. Under the right circumstances, nudging in the opposite direction can also work.
-
You're right, of course. With this thread as the impetus, I've actually been thinking about it from a point of view opposite that of the OP. I guess guf isn't clear about whether he started at 120 and turned it up, or started at some lower point and turned it up to 120 ... did he say and I just missed it? Anyway, he got me thinking about where I set the subs to kick in. By default I set mine around 100Hz, which my subs are completely comfortable with, and then just fiddle with the level until it sounds right on a variety of music. Not very scientific, but I trust my ears to tell me what they like.
After this thread popped up, I got thinking about *why* I was at 100Hz. My Omegas operate full-range, after all (which really isn't FULL range but easing into the 40s, giving more than an octave of overlap). I started lowering the crossover point and found that right around 70Hz (with a slight nudge up in volume) kept the deep bass but cleared up a slight thickness that I hadn't realized was there. Under the right circumstances, nudging in the opposite direction can also work.
One point to keep in mind is that in almost all cases the crossover "point" is not a point at all, but a point at which high and low pass elements are both 3dB down. The slopes to get to this point may be so shallow as to start two or three octaves above or below the crossover point.
When running my own Omega's full range, they act a bit like a sealed box, falling off gently beginning about 200hz or so. Depending on where they are positioned in the room, I have to adjust the subwoofer crossover point to blend in. With my subwoofers, I can adjust output level, phase, crossover frequency and slope. I've found the natural asymmetrical slope (6dB HP, 12dB LP) helps fill in the bottom while preserving the illusion that deep bass is coming from the mains.
An advantage of this method is the the bass gain can be adjusted independently of the gain for the mains, allowing me to simply turn the bass up or down (or off) depending on need.
-
With my subwoofers, I can adjust output level, phase, crossover frequency and slope. I've found the natural asymmetrical slope (6dB HP, 12dB LP) helps fill in the bottom while preserving the illusion that deep bass is coming from the mains.
Interesting. What crossover do you use? The crossovers in my little Dayton APA-150 amps aren't that flexible, but then I didn't expect them to sound good enough to keep this long! Speaking of "preserving the illusion," for a couple days last week I had my Fried subs and satellites and a pair of Fried Studio IVs — along with my Omegas — in my tiny (roughly 10x11) listening room. At one point I caught my wife sitting in there listening to the music and I asked her if she could tell which speakers were playing. The correct answer was the Omegas along with the subs in the background, but I liked her response: "Aren't all of them playing?"
(http://www.audiocircle.com/image.php?id=175445)
-
I tried a few different high pass filters between my pre-amp / DAC and amp to remove some of the low frequencies and let my deepOmega8 carry more of the load. I could never get it sounding right, but I only have a single deepOmega8. At the db levels I listen at, letting my Omegas run full-range seems to work best for me. I don't recall what my deepOmega8 is crossed over at, but it's at or a bit lower than 100Hz. Setting the cross-over to ~120Hz always sounded a bit too flabby in my room.