AudioNervosa
Systemic Development => Speakers => Topic started by: rollo on July 31, 2017, 01:26:01 PM
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At what price level does one expect 20HZ bass response done right meaning -3db point at 17HZ. For me after the 5K region I want 20HZ bass.
charles
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The question should be
Is your room big enough to make 20 hz?
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At what price level does one expect 20HZ bass response done right meaning -3db point at 17HZ. For me after the 5K region I want 20HZ bass.
charles
You mean you expect a speaker to be able to go down to 20Hz at $5K price point?
Is there such a thing in existence?
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I want mine to go down to 11
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Depends on how loud you want the bass since most distortion modes for speakers increase exponentially with SPL. Even very good bass speakers can still have 10% distortion at 20Hz 90dB while mid and tweeters can be below .1%.
And Mike is absolutely right, the biggest source of bass distortion in a normal sized house is gonna be room modes from too small rooms. https://www.acousticfields.com/wavelengths-in-our-rooms/
So here's a bass strategy that drastically reduces both speaker distortion and room distortion and cost:
Put the largest possible bass driver you can afford like 18" (for maximum acoustic impedence = detail, lowest distortion because minimum excursion) and place it as close as possible to your head at listening position. On a stand behind you, or hanging from ceiling above you, etc. The closer it is, the more you can to turn down the bass level to match the distant main speakers and achieve flat FR. The actual SPL from the bass drivers will be very low, minimizing room and speaker distortion, and increase headroom dramatically, maybe like 20dB! Don't be tempted to use a small bass driver that can more easily fit on a stand or WAF, because a small cone has poor acoustic impededence and gives up detail and adds distortion, the liability increasing with lower frequencies and lower volumes. You need a large cone to play soft and keep the detail and slam.
It's inexpensive because you can use a smaller amp, and you need less room treatment. In smaller house rooms you can only do so much with treatments. They can't cure everything. So keep physics on your side.
The bass from commercial speakers I've heard is Legacy Whisper. Each side has 4 15" drivers in open baffle. I heard a tenor blues singer accompanied by a tuba. OMG, unbelievable bass detail dynamics and realism! Acoustic impedance at bass frequencies is good, not as good as any cheap tweeter, but far far better than a 6" woofer trying to play 40Hz.
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Bass has always...and probably will continue to be...the lacking element in my system. It's been the least of my priorities and likely because it would be the hardest to achieve. The SP Tech is a two way with a small midwoofer. My room is likely too small as well.
I've always thought highly of Bill Dudleston and Legacy. An interesting and less costly experiment might be for me to try a Hsu sub. But placing it behind me...I think my wife wouldn't allow it
Nick
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At what price level does one expect 20HZ bass response done right meaning -3db point at 17HZ. For me after the 5K region I want 20HZ bass.
charles
You mean you expect a speaker to be able to go down to 20Hz at $5K price point?
Is there such a thing in existence?
Yes I do.
charles
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The question should be
Is your room big enough to make 20 hz?
Good point. However not a concern for this discussion. Lets assume the room can produce the bass.
charles
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Bass has always...and probably will continue to be...the lacking element in my system. It's been the least of my priorities and likely because it would be the hardest to achieve. The SP Tech is a two way with a small midwoofer. My room is likely too small as well.
I've always thought highly of Bill Dudleston and Legacy. An interesting and less costly experiment might be for me to try a Hsu sub. But placing it behind me...I think my wife wouldn't allow it
Nick
Nick you could put that HSU under a table behind you set out of phase and both be happy. Yes a nice table with a cloth over the sides to hide the beast a glass of wine and babies come. Oh my ! However if you had a speaker for the right price which did 20HZ or 25HZ game over so my point of the post.
charles
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Bass has always...and probably will continue to be...the lacking element in my system. It's been the least of my priorities and likely because it would be the hardest to achieve. The SP Tech is a two way with a small midwoofer. My room is likely too small as well.
I've always thought highly of Bill Dudleston and Legacy. An interesting and less costly experiment might be for me to try a Hsu sub. But placing it behind me...I think my wife wouldn't allow it
Nick
Nick you could put that HSU under a table behind you set out of phase and both be happy. Yes a nice table with a cloth over the sides to hide the beast a glass of wine and babies come. Oh my ! However if you had a speaker for the right price which did 20HZ or 25HZ game over so my point of the post.
charles
A nice thought, Charles. I need to sell my living room cabinet to make more room for my "stuff". Might be feasible in a year.
Nick
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I just heard Gregs latest iteration of his speakers today
, a single full range panel with no crossover.
I believe it was 40 hz to 6K and man it sounded great. Big deep image tremendous separation and tone oh my!
This was not a finished set of panels , they were just assembled last night and he said he had a lot more work to do to the panels before they could be considered done. But even in this early stage of build they sounded great.
Of course they get better with the tweeters and the subs,which will be built next, but oh my! it was wonderful.
40 hz seems good enough for me, a little more weight that the subs would provide would be nicer but I don't see the need to go down to 20 hz, unless you play organ music and can hear 20 hz!
I think 20 hz is just for bragging rights.
Like in cars they brag about horsepower,, horsepower sells cars but torque wins the race, but no one even cares or knows about torque.
So for me 20 hz was and is a sales ploy, preying on the insecure audiophile, like the little guy with a big truck, or the little guy with the big mean dog, I always say big truck little pee pee....
So if your speakers don't go down to 20 hz , don't feel bad, because honestly your room can't make it anyway...
Just my opinion, all flavored and colored up to my liking,,,,,
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The sub 20Hz capability is seldom used in my system, but I will admit to enjoying organ music at high SPLs.
It may not be an absolute requirement for an "Audiophile" approved speaker system, but it is a frequently used benchmark.
32Hz is the threshold where bass is equally heard and felt, frequencies below 32Hz are progressively felt more than heard as a tone. When test signals below 25Hz are played back in my listening room it is as though there is something present in the room with you, but you can tell exactly what it is. Spooky in word. Great way to "haunt" a house.
The last octave from 20 to 40Hz. is where hall ambiance in classical music lives. The recreation of the artificially created acoustic space found in some studio recordings is also very dependent on the low frequency extension the speaker system has.
Scotty
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^ :)
I agree that the lowest octave adds a ton of drama and emotion and is valuable to a music lover. Humans are programmed genetically to fear loud and low noises, so ultra-LF content triggers our reptile brain to squirt adrenaline. Composers know this and put the musical thunder in there deliberately. Prokofiev is an awesome composer for symphonic bass drum. Check this particular recording of Lt. Kije Suite (https://smile.amazon.com/Prokofiev-Lieutenant-Britten-Persons-Orchestra/dp/B00000426C), a film soundtrack he wrote in the 20s. People love their hotrods and Harleys, airshows, Niagara Falls and sonic booms for the incomparable thrill of the sound. U2's huge concert sound was from the bassist's foot operated synth bass doubling under his fender bass the root notes in the chorus. Awesome!
If the bass rolls off too high like in mid-bass then you get phase shift with the rolloff. This phase distortion, or group delay is said to be the cause of the infamous "slow bass." All bass is slow of course, but time misalignment with the midrange where the speed information happens makes bass sound separate from the music and slow. The lower and flatter the bass extends, the lower the phase shift happens, so ideally, with flat extension to 20Hz or below, the rolloff and the phase distortion happen below the "audible" range and you don't have the dreaded slow bass.
But to reach 20Hz and still have some grip on the air to make musical texture and not just sine waves you need excellent acoustic impedance to the surrounding air. Which means several very large diaphragms with large excursion, or an air to air transducer, like reflex port or organ pipe. The smaller the bass driver cone, the worse the impedance to the air, the more sloppy the grip, the softer the SPL and the more the sound is like a sine wave, no texture at all and no excitement. You need largest area diaphragm possible to get the ultra LF texture and detail. The larger the better because these LF wavelengths are 50 feet long, played by a 1.5 foot cone. Compare that to a tweeter playing a 1.5" wavelength at 10kHz with a 1" diaphragm, it takes only a couple watts to play just as loud as the bass driver using 1000W at 20hz. We love the tweeter detail, we love the bass detail, but that's a bit harder and more expensive to pull off.
And there is plenty of detail down there. Fender bass makes mostly sine waves, so small drivers don't hurt too bad playing classic rock, but synths and acoustic instruments make far more texture. Square wave bass is what the kids really want -
the sound of alien laser guns blowing up planets. For instance I have a recording of Tchaikovsky 1812 Overture. It has full size military artillery cannons shooting outside. You can hear the reflections of the booms bouncing off nearby hills or buildings and there is all kind of other reflection information in that .5 second delay. It was all audible on my old Legacy Focus 2020 speakers with 3 12" woofers and two 2" reflex ports per side. No other speaker I've had since then could match it. I connected NuForce amps directly to the speakers and play the full 2V line signal into them with no attenuation. I stood 40 feet away in the kitchen cooking dinner, but that incredible bass would have me falling on the floor overcome with emotion. Yes, it's worth it, and it's musical, not just a audiophile trick.
The audible range is not the limit of perception. We can feel the vibrations below what we can hear with ears. If the transducer has sufficient acoustic impedance to affect the surrounding air then you can feel the subsonic vibration in the air.
You can hear texture and detail in LF sound just like you can hear it in thunderclap made by a 2 mile long "line array" lightning bolt. No driver cone has big enough area to do that, so it must be created by an air to air transducer, like an organ pipe or reflex port, or lightning bolt.
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I am lucky that my wife cares more about how a system sounds than how it looks. Two twelves per side in the mains and 2 other subs in the room to flatten bass response irregularities.
Funny thing, my speakers are almost the same size as the Legacy 2020s at 55.5in. X 14.5in. X 17.5in. and 185lbs. in weight. slot loaded front port.
Something to do with physics. ;)
Scotty
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^ :)
I agree that the lowest octave adds a ton of drama and emotion and is valuable to a music lover. Humans are programmed genetically to fear loud and low noises, so ultra-LF content triggers our reptile brain to squirt adrenaline. Composers know this and put the musical thunder in there deliberately. Prokofiev is an awesome composer for symphonic bass drum. Check this particular recording of Lt. Kije Suite (https://smile.amazon.com/Prokofiev-Lieutenant-Britten-Persons-Orchestra/dp/B00000426C), a film soundtrack he wrote in the 20s. People love their hotrods and Harleys, airshows, Niagara Falls and sonic booms for the incomparable thrill of the sound. U2's huge concert sound was from the bassist's foot operated synth bass doubling under his fender bass the root notes in the chorus. Awesome!
If the bass rolls off too high like in mid-bass then you get phase shift with the rolloff. This phase distortion, or group delay is said to be the cause of the infamous "slow bass." All bass is slow of course, but time misalignment with the midrange where the speed information happens makes bass sound separate from the music and slow. The lower and flatter the bass extends, the lower the phase shift happens, so ideally, with flat extension to 20Hz or below, the rolloff and the phase distortion happen below the "audible" range and you don't have the dreaded slow bass.
But to reach 20Hz and still have some grip on the air to make musical texture and not just sine waves you need excellent acoustic impedance to the surrounding air. Which means several very large diaphragms with large excursion, or an air to air transducer, like reflex port or organ pipe. The smaller the bass driver cone, the worse the impedance to the air, the more sloppy the grip, the softer the SPL and the more the sound is like a sine wave, no texture at all and no excitement. You need largest area diaphragm possible to get the ultra LF texture and detail. The larger the better because these LF wavelengths are 50 feet long, played by a 1.5 foot cone. Compare that to a tweeter playing a 1.5" wavelength at 10kHz with a 1" diaphragm, it takes only a couple watts to play just as loud as the bass driver using 1000W at 20hz. We love the tweeter detail, we love the bass detail, but that's a bit harder and more expensive to pull off.
And there is plenty of detail down there. Fender bass makes mostly sine waves, so small drivers don't hurt too bad playing classic rock, but synths and acoustic instruments make far more texture. Square wave bass is what the kids really want -
the sound of alien laser guns blowing up planets. For instance I have a recording of Tchaikovsky 1812 Overture. It has full size military artillery cannons shooting outside. You can hear the reflections of the booms bouncing off nearby hills or buildings and there is all kind of other reflection information in that .5 second delay. It was all audible on my old Legacy Focus 2020 speakers with 3 12" woofers and two 2" reflex ports per side. No other speaker I've had since then could match it. I connected NuForce amps directly to the speakers and play the full 2V line signal into them with no attenuation. I stood 40 feet away in the kitchen cooking dinner, but that incredible bass would have me falling on the floor overcome with emotion. Yes, it's worth it, and it's musical, not just a audiophile trick.
The audible range is not the limit of perception. We can feel the vibrations below what we can hear with ears. If the transducer has sufficient acoustic impedance to affect the surrounding air then you can feel the subsonic vibration in the air.
You can hear texture and detail in LF sound just like you can hear it in thunderclap made by a 2 mile long "line array" lightning bolt. No driver cone has big enough area to do that, so it must be created by an air to air transducer, like an organ pipe or reflex port, or lightning bolt.
Thanks for your perspective, Rich. Maybe some day I can experience that in my surroundings.
Nick
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I agree there is a lot of info down there, but what percentage of commercially available speakers actually go down that far with meaningful spls?
How many of us audiophiles out there have speakers that go down to 20 hz? Realistic 20 hz not just 20 hz down 20 dbs so it looks good on paper.
How many people whose speakers do not go down that low realistically, enjoy their speakers?
I would imagine most if not all.
I enjoy my crappy car radio, and that is missing so much from everywhere , top bottom and sides!
I think the main problem with going down that low is size, you need large drivers and hence a large cabinet, of course if gets a bit more expensive to manufacture and ship larger speakers, but the most restrictive part I believe is most people can't, or won.t, use a giant speaker in their house.
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I agree there is a lot of info down there, but what percentage of commercially available speakers actually go down that far with meaningful spls?
How many of us audiophiles out there have speakers that go down to 20 hz? Realistic 20 hz not just 20 hz down 20 dbs so it looks good on paper.
How many people whose speakers do not go down that low realistically, enjoy their speakers?
I would imagine most if not all.
I enjoy my crappy car radio, and that is missing so much from everywhere , top bottom and sides!
I think the main problem with going down that low is size, you need large drivers and hence a large cabinet, of course if gets a bit more expensive to manufacture and ship larger speakers, but the most restrictive part I believe is most people can't, or won.t, use a giant speaker in their house.
Well, no problem with your opinion, but the original post didn't start out this way. I do enjoy my favorite tunes even on the crappiest of boom boxes. Part of the joy of audio ..for me at least ....is to appreciate that others have the space, means and money to own things that I can't afford or don't even necessarily want. This discussion has given me a different perspective and maybe at some point I'll try a sub and see if it brings me more musical enjoyment.
Nick
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Well the original posts asks how much do you think you should spend to go down to 20hz?
any cheap sub will go down to 20hz..
for Wilson audio speakers you may have to spend $40,000 to get to 20hz.
Legacy maybe $15,000, every speaker maker has their own price points
The question of how much audio gear costs is kind of taboo around here so I think the thread drifted to a more innocent and more interesting aspect of bass performance.
Great bass performance doesn't have to be expensive the big 15 inch drivers are not really that expensive, high end tweeters cost much more, but great bass does take a lot of room to make, no getting around that..
Audio Note makes a two way speaker for S275K with an 8 inch woofer, so there you go!
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The way I interpreted Charles' post is that his expectation is for a pair of speakers should go down to 20Hz once they passed the $5K mark.
My original reaction/thought was, and I admitted I misread somehow, he expected to get 20Hz at $5K and thus my question.
I could be wrong though.
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Agree. That's how it started out. It's not my strength to stay on topic sometimes. I tend to drift a bit, but that can lead into more interesting conversations. As I said, I've gotten a different perspective on bass reproduction and appreciate that. I also wanted to keep a positive tone on the posts.
The subject of mentioning the cost of gear isn't a problem for me at all. I just looked at a video of the Living Voice system. $2,000,000 and eight sold. Works for me if you can afford it.
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Yes achieving bass performance does require some payment to the gods. Nothing is free in life. Big dreams are worth fighting for. Stop dreaming and you are the walking dead.
My proposed great bass solution would cost $2000 diy, $5000 bought and give sota bass performance. So no govt price controls needed. If you dream of Alexandria's then get them, but your bass will not be better than my head sub. Of course there are many fine reasons to buy Alexandrias or AudioNotes and to believe their bass is the best possible. We create our own dreams and live in them.
Price, size, who cares about that? Surely, not audiophiles. We don't care about those things. Of course it's the WAF, as usual.
Top tip: The man causes the WAF problems. We can learn a lot about WAF from shek's male lions. (http://www.audionervosa.com/index.php?topic=6322.msg80971#msg80971)
Every man needs a cedar tree and at least 2 18" subs to be happy.
(http://www.noiseaddicts.com/wp-content/uploads/2008/07/matterhorn.jpg)
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Well,
knowing the original poster personally I imagine the thread was going to drift to the fact that he is thinking of buying a speaker that goes down to 20hz. That is all well and good, but these tangents do tend to become more interesting when they drift.
First time I heard open baffle bass was in RMAF in 2007, Nelson Pass had built these OB subs in plywood, just hanging in the wind, and they sounded great...fast, clean,effortless, no box boom like a home theatre sub, much more musical, such deftness, like a real acoustic bass, like the bass came out of the f holes in the double bass, very very musical.
I remeber the first time I heard the IRS system at Bill Legalls house, completely rebuilt by him, I walked into this big room and saw these monster speakers surrounded by huge woofer panels, when he turned it on I thought I would be pushed against the back walls, all those woofers so imposing!!, But what I felt was the opposite, such a huge open delicate sound, so effortless, not like a nightclub at all, but like live music.
Rich is right you need big woofers and lots of them makes it better, but not how you would expect , not like a row of Marshall stacks, but they deliver such delicateness that is truly special. Extreme clean , fresh extended bass, super fast and lively, and so very natural sounding.
just my opinion all colored up and sticky
mike
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big bass
https://www.youtube.com/watch?v=o36Kp6veJ6c
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The vast majority of people out there have very little, if any source material that goes down below 30 Hz and even if they did do not have a room that would support it. but from a marketing perspective it is damn near impossible to sell a "full range" speaker that does not at least on paper, under some test conditions, measure well down to 20 hz.
Whether or not they will ever use that full bottom octave is immaterial. But have the theoretical ability to do so seems to be a psychological barrier for many audiophiles.
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Much agreed
audiophiles do tend to be number weenies, and 20 hz is certainly a bragging right even if they never really heard it in their room!
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At what price level does one expect 20HZ bass response done right meaning -3db point at 17HZ. For me after the 5K region I want 20HZ bass. AT 15hz, 34mm.
charles
That is going to be tough as huge cone excursion comes into play, depending upon driver diameter and spl.
For my test speaker, I decided to use a 12" with -3db at 30hz, but at 19-20hz is -13db, in two 4.5 ft3 cabinets. Even then, cone excursion is the limiting factor at 30hz.
Here is a link to calculate excursion. With a 12" woofer, at 40hz, 100db spl, about 4.8mm excursion. All being the same except 20hz, the excursion is near 19mm, 3/4".
http://www.baudline.com/erik/bass/xmaxer.html
Cheers and hope this helps.
Steve
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I like multiple 12" servo drivers in an OB H-Frame. The two 6x12's here do very well with pipe organ music. You can feel the infrasonics on some recordings.
Have not tried the 2x12's OB servos yet but they should do nicely as the tuned at 22Hz with the Linkwitz transform.
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I like multiple 12" servo drivers in an OB H-Frame. The two 6x12's here do very well with pipe organ music. You can feel the infrasonics on some recordings.
Have not tried the 2x12's OB servos yet but they should do nicely as the tuned at 22Hz with the Linkwitz transform.
Are you saying you are using two groups of 6 drivers, all 6 are 12" in diameter?
Cheers and thanks.
steve
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Yes, two 6x12" H-frame OB servo sub towers.
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Yes, two 6x12" H-frame OB servo sub towers.
So 12 total drivers, each 12" dia. Wow, that should do the job.
Cheers
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Yes. Best bass I have ever heard for music.
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At what price level does one expect 20HZ bass response done right meaning -3db point at 17HZ. For me after the 5K region I want 20HZ bass. AT 15hz, 34mm.
charles
That is going to be tough as huge cone excursion comes into play, depending upon driver diameter and spl.
For my test speaker, I decided to use a 12" with -3db at 30hz, but at 19-20hz is -13db, in two 4.5 ft3 cabinets. Even then, cone excursion is the limiting factor at 30hz.
Here is a link to calculate excursion. With a 12" woofer, at 40hz, 100db spl, about 4.8mm excursion. All being the same except 20hz, the excursion is near 19mm, 3/4".
http://www.baudline.com/erik/bass/xmaxer.html
Cheers and hope this helps.
Steve
Thanks for posting that website, Steve. It has made it much easier to understand how the various goals and design elements for speakers work together.
Nick
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At what price level does one expect 20HZ bass response done right meaning -3db point at 17HZ. For me after the 5K region I want 20HZ bass. AT 15hz, 34mm.
charles
That is going to be tough as huge cone excursion comes into play, depending upon driver diameter and spl.
For my test speaker, I decided to use a 12" with -3db at 30hz, but at 19-20hz is -13db, in two 4.5 ft3 cabinets. Even then, cone excursion is the limiting factor at 30hz.
Here is a link to calculate excursion. With a 12" woofer, at 40hz, 100db spl, about 4.8mm excursion. All being the same except 20hz, the excursion is near 19mm, 3/4".
http://www.baudline.com/erik/bass/xmaxer.html
Cheers and hope this helps.
Steve
Thanks for posting that website, Steve. It has made it much easier to understand how the various goals and design elements for speakers work together.
Nick
Your quite welcome Nick.
For others not familiar with deep bass problems. Hal's design works nicely with deep bass as it minimizes cone excursion, and lower harmonic distortion. The down side is the physical size, think of twelve 12" woofers in a room. Cost?
Cheers
steve
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Depending on who makes the H-frame cabinets, the two DIY 6x12 servo subs from flat packs I did were around $7000.
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I remember the first time I heard GR Research H-frames. Danny was exhibiting in a relatively small room at RMAF (20 X 15 X 8). I had a recording of Pete Belasco's "Deeper" with me. The LF fundamental of the 808 drop (inside base ball) had been pitch corrected from the original 18Hz all the way up to 21.3Hz. I was standing in the hallway talking to another member of the Insane Audio Posse when the first drop hit in the room. The hallway door was closed. Moved my world. My friend Lowell had a WTF look on his face, so I waited for the next one with my fingertip about 1/8" from the outer corridor wall. That wall hit me finger as it shuddered due to room compression.
Changed my life.
Not only was the LF extension there, but the utter tunefulness and astonishing detail made my mind up, then and there.
I have heard those subs in almost every possible setting possible including my own listening room. When properly implemented, powered by the amp built for them and given every possible setting I can, with no hesitation state that they produce the deepest, most authentic LF available.
I've listened to crazy built into the floor bass horns, Wilson Thors Hammers ,REL, HSU and on and on. Nothing has approached the performance and absolute musicality of them. I can only imagine Rich's 6 X 12's. Even the 2 X 12's are awesome in most systems. Brian Ding and Danny Richie truly really represent SOTA in LF reproduction. Probably move one's bowels ... Not really: the "brown note" is around 9Hz. Don't go there...
Just sayin' ...
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9hz huh? Never been there as far as I know but it sounds moving (and colorful).
Iv'e got dual 10s per speaker and different amplification changes a lot in the LF for me.
So speaker cost alone doesn't combat bass performance provided your talking decent bass
vs just being there in some bloated soggy form.
Don
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Dave,
This might give you an idea.
This plot is at my listening seat 11' from the bass array and 8' from the ribbon/planar line array. Time delays are corrected in the dspMusikLCD digital crossover.
Working on the peak and node with room treatment now. It pretty much sounds like real instruments in an acoustic space.
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As per the original post regarding speakers that play full range. My first thought is, why?
I typically and specifically don't want my main speakers to play down that low for several reasons.
First of all, those low wavelengths are tough to reproduce passively. It requires large heavy woofers and demands an amplifier with plenty of power and the ability to deliver plenty of current. If you relieve the main speakers and amp of just the first octave you make both much more capable of covering everything else. It almost doubles the head room of the amp. And with a woofer not being worked by those long exertions it (or they) can much more easily handle the shorter ones.
Now relieve low frequency duty even further for another half octave or so and your main speakers and amps are freed up significantly.
Secondly, and again, handling the bottom octave with a passive speaker means a very heavy moving mass driver with a low Fs. Unfortunately that means a LOT of stored energy. That equates to slow sluggish bass response especially at high volumes. Bass can simply become a blurry boom.
Third, you really want to place your speakers where they are ideal in the room for imaging and sound stage layering and not for bass response. You don't want to be stuck with whatever bass response the speakers produce because of what they do in an ideal location for speaker placement.
And ideally you really want and need some adjustable control over the lower ranges. It is too easy for a large speaker to overload a room in the lower ranges and then you're stuck with a limited amount of attenuation adjustment with bass traps and room treatment. This can be seen (or heard) at any audio show. It is easy to find a room with boomy bass. If you've been to a show then you know this.
If the lower ranges are covered by a separate sub and amp system then you have some ability to balance the response.
And with our servo subs the control system allows you to do almost anything you want. You can even EQ out a peak or a dip. You can even use open baffle subs or multiple subs to balance out the way bass loads the room. You can't do that with a full range passive speaker.
And smaller is faster especially with servo control. Our 12" woofers will play flat to 20Hz and easily hit -3db numbers in the teens. So why go to a bigger woofer? Some will say that a bigger woofer will move more air. Well yes and no. Potentially it can, but at 85db, 90db, 95db or even 100db they are actually moving the same amount of air. But a larger woofer is still heavier, has more stored energy, and takes longer to return to rest. So it does not sound as good. Yes, but it can move more air totally, thus hitting a higher SPL level. True, but then two 12" woofers can move more air, hit higher SPL levels and still settle much faster. Use of multiple woofers really means each woofer has to move less to hit the same SPL levels as a larger single woofer. So settling time is even further reduced. Throw in servo control and you're at a whole different level.
And what does it cost? Add a servo sub to a pair of mini-monitors and your system is now full range and for a fraction of the cost of any full range speakers that you can find. And the servo subs will still play lower and sound better.
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As per the original post regarding speakers that play full range. My first thought is, why?
There are several reasons Danny. My first questions would be:
1) What is the maximum spl one is looking for. Peaks of 100db work for me. Of course, others may wish for higher spls.
2) If multiple different type amplifiers are used. Whether solid state and tube, or tube and tube of different manufacturers or even models, the ear is very sensitive to sonic differences when blending. Separate amps have different sonic qualities. I have yet to hear seamless blending at shows, anyone using separate subwoofers. Of course most have average to good systems, so blending may not be as important, which I understand.
In my research, changes in as little as 1 part in 300,000 in resistor value is quite perceptible, as it slightly alters the response. I have found that 10 parallel 18 gauge wire is optimal for my system's sonics, not 8 nor 12. (Of course I have adjustments on my speakers.
With such sensitivity, I personally never mix different type of amplifiers due to blending problem perceptions. I also do not use separate sub-woofers. I simply use the same 25 watt/ch amplifier for both bass and treble for a seamless blend.
YMMV though.
cheers
steve
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SPL levels are actually easier to hit with separates, and easier to control.
And blending separate subs is actually real easy if done right. It really has little to do with different types of amps. The difference really comes from driver speed. The difference in damping factors of the amps is nothing compared to the moving mass of the drivers in most cases.
For instance take a mini-monitor or small floor standing speaker and try to match the speed (and by speed I mean settling time) with a large and heavy low frequency driver . That's where you get the mis-match, and poor blending.
Another issue that I didn't mention earlier is that the larger voice coil of the bigger driver can create a large back EMF that effects (negatively) everything else. So when driven by the same amp they tend to muddy the output of other drivers. They can sound blended or more smeared together but not in a good way.
If you want to spend a little time with wire and listening comparisons then you will find that the geometry of the wire, quality of the wire, and dielectric material to have a much greater effect then the gauge of the wire.
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Steve, I was very much in the same camp as you for many, many years. That all changed when I heard the GR open baffles. First, they are not accelerometer based. The sensor coil is precise and honest. Accelerometer sensed subs always sound broken to me. One of the things that impressed me was the seamless integration with the mid driver. I credit that completely to choosing the right amp and driver to integrate with the H-frames. I can name a dozen mid drivers that would not do the trick. A lot of this was just great choice of drivers. The other thing is the uncolored nature of open baffle lows. It really is stunning in timbre, dynamics and effortless sound.
They simply rock with the right amp choice
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Agree with both Danny and dBe.
Best integration of a sub to mains I have ever heard with either the 2x12 or 6x12 H-frame servo subs. Much easier to integrate with the room as well.
The radiation pattern from the open baffle subs solves a lot of side wall and ceiling interactions that a box or ported sub excites.
My best suggestion is to get to hear them for yourself when possible. The 2x12 and 6x12 H-frames servo subs were at CAF2017 and probably will be at CAF2018. There maybe more than one room with them at CAF2018.
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Well, well, well, I stand corrected. Makes sense Danny. IMo the OB "H" frames are the ones to beat. Great DIY product.
charles
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SPL levels are actually easier to hit with separates, and easier to control.
My point is that unless one needs very high spls, that amp power becomes a non factor, except for possibleaverage SETs. My 20 watter handles my two ways to 100db spl.
And blending separate subs is actually real easy if done right. It really has little to do with different types of amps. The difference really comes from driver speed. The difference in damping factors of the amps is nothing compared to the moving mass of the drivers in most cases.
It has everything to do with different amplifiers and their differing sonic characters. As an example, try combining a bright sounding amplifier (for the tweeter) with a full sounding amplifier (for the woofer). It is quite easy to perceive a disjointed quality in the sound.
Driver speed is not that much of a problem. Often the cause of "slow" vs "quick" "speed" is the phase relationship between the fundamental and harmonics of said driver.
For higher frequency drivers, check the FR and cone resonance properties, as well as the Qs. For the woofer, again check the cone resonance properties and the Qs. If one is having "energy storage" problems, either the drivers have a problem to begin with, or the cabinet/design is problematic and the final Qs of the system is incorrect.
I have a control to adjust the Q of my woofer at resonance. I believe in controls on speakers.
For instance take a mini-monitor or small floor standing speaker and try to match the speed (and by speed I mean settling time) with a large and heavy low frequency driver . That's where you get the mis-match, and poor blending.
That is a function of the phase relationship between the fundamental and harmonics. The smaller mini will have the harmonics slightly ahead of the fundamental due to its lack of low frequency respone, which gives a steeper slope, thus "faster" time. It can be too "fast". The trick is to obtain the proper rise time (attack time) for said instruments.
Another issue that I didn't mention earlier is that the larger voice coil of the bigger driver can create a large back EMF that effects (negatively) everything else. So when driven by the same amp they tend to muddy the output of other drivers. They can sound blended or more smeared together but not in a good way.
That is where the proper xover design comes in. I have no problems with such, demonstrated by the fact that I am dealing with 1 part in 300,000 (resistor value). In other wards, I am dealing with FR etc changes so small they equate to -110db down from the fundamental. The ear is that sensitive. One will not obtain that precision of blending using a typical subwoofer amp xover controls etc. Sounds like you are discussing a problem with a total Q that is too high.
Another point is that the typical xover, whether reg speaker or subwoofer, does not have the fine tuning necessary to seamlessly blend different drivers.
If you want to spend a little time with wire and listening comparisons then you will find that the geometry of the wire, quality of the wire, and dielectric material to have a much greater effect then the gauge of the wire.
I have dealt with several types of wire, and as you point out, a variety of factors influence the sound. Included in the list are your generalities; to be more specific, materials used, solid or stranded, total gauge and paralleling of individual wires. Here is a quote from a previous post I made addressing the high frequency response of one vs paralleling wires. I altered the quote slightly, an update.
Inductance is frequency dependent. For comparison, below is the DC resistance, the straight wire inductance, and inductive reactance for 5 feet of single wire and parallel wires at 20khz:
Single Single Single 10 parallel
18 gauge wire 13 ga. ~9 ga. 18 ga.
.0325 .0104 .0066 .0065 DC resistance
2410 nh 2232 nh 2162 nh 240 nh Inductance
.30 ohms .28 ohms .27 ohms .03 ohms Inductive reactance at 20khz
Notice the 10 parallel 18 gauge wires equate to an approximate 9 gauge wire in DC resistance, but the inductive reactance is only 1/9 that of the 9 gauge wire.
(You may have heard the past arguments over the small wire parallel with the large wire improving the highs. The highs were increased because the inductance of the two wires was about 1/2 that of a single wire.)
Remember, this is for a single 5 foot lead, not both leads. Multiply this by 2 for the total 10 feet speaker lead length. I would say .54 ohms is quite a bit in series with a 4 ohm, or 8 ohm speaker, although the impedance of a speaker at 20khz is higher. One could easily be about half a db down at 20khz, a couple of tenths at 10khz and even a tenth at 5khz. Whether one notices a difference will depend upon some factors. I and friends perceived a difference between 8, 10,, and 12 parallel wires per lead. Bass resonance is also affected and perceived.
Concerning low frequencies, multiple actions occur.
1) The damping of the woofer resonance via reduced resistance to the output of the amplifier is enhanced by larger gauge wire (comparison using same material wire).
2) All drivers are influenced by the gauge of the wire due to the combination of wire resistance (and impedance) and varying impedance of each driver. Of course this does not occur with constant impedance speakers, such as magnepans etc.
One final point. The effect of one's personal tastes will also affect perception. As at Audio Fest's, one hears a variety of tonal balance in the different rooms. The range I have observed are from very full sounding to that of sterile. As such, the fuller sounding rooms will probably have little problems with matching drivers, even using different sounding amplifiers. The opposite will occur with the sterile sounding rooms, where different amplifiers and their characteristics will be perceived more easily.
The last point is that I am not personally attacking any of your products Danny. I have heard great things about your speakers. I am just providing information, responding to the OPs question, and your question; why I use one amplifier for both drivers in my speakers. I addressed multiple problems that need addressing.
cheers
steve
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Steve I understand andf xcan appriciate everything you said, but one thing is that most of us do not have your kind of talent or expeience and as such do not have access to the kind of hand tweaked eq
I understand and apologize if I come across in a poor way T, and others. Sometimes I feel that some ways of doing things get dumped on, when my own experiences say there is merit. I am also looking at what can be accomplished, pushing the borders of improvement.
cheers and no harm meant.
steve
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I think the key to good bass, beyond effectively controlling resonance problems below the rooms Schroeder frequency, is ensuring that the woofer accurately tracks and reproduces the incoming bass signal.
A woofers intrinsic setting time or its rise and fall time only has to be the same or slightly faster than the incoming electrical waveform. It can't be as fast as drivers with lower moving mass and fortunately it doesn't have to be.
Unfortunately, I suspect that most of the time the woofers unassisted setting time may be slower than that of the electrical signal driving it, leading to a less than realistic reproduction bass instruments. This where servo control of the woofers signal tracking behavior, in particular, the ability to force the woofer to closely follow the bass waveforms decay characteristics through error correction, comes into its own. There really is no substitute for active control of the woofer, especially if listening to music with synthesizer bass content, which can exhibit bass waveform characteristics that are not subject to the physics that govern real world instruments, such as moving mass.
Obviously the dynamic driver based dipole subwoofer cannot function properly without the presence of servo control of the woofer.
I think quite satisfactory results could also be obtained from a boxed based subwoofer system in a room, albeit, at a greater cost when compared to a H-box based design.
Scotty
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I think the key to good bass, beyond effectively controlling resonance problems below the rooms Schroeder frequency, is ensuring that the woofer accurately tracks and reproduces the incoming bass signal.
A woofers intrinsic setting time or its rise and fall time only has to be the same or slightly faster than the incoming electrical waveform. It can't be as fast as drivers with lower moving mass and fortunately it doesn't have to be.
Unfortunately, I suspect that most of the time the woofers unassisted setting time may be slower than that of the electrical signal driving it, leading to a less than realistic reproduction bass instruments. This where servo control of the woofers signal tracking behavior, in particular, the ability to force the woofer to closely follow the bass waveforms decay characteristics through error correction, comes into its own. There really is no substitute for active control of the woofer, especially if listening to music with synthesizer bass content, which can exhibit bass waveform characteristics that are not subject to the physics that govern real world instruments, such as moving mass.
Obviously the dynamic driver based dipole subwoofer cannot function properly without the presence of servo control of the woofer.
I think quite satisfactory results could also be obtained from a boxed based subwoofer system in a room, albeit, at a greater cost when compared to a H-box based design.
Scotty
I agree if I understand you correctly Scotty. The problem is to keep the total Q about 0,7 or below, such that energy applied are absorbed via various means. This would include optimal losses due to electrical, mechanical of the driver, and the enclosure, whether open or closed.
Above ~0,7, then I agree some sort of feedback/servo control would be beneficial. The higher the total Q, the more energy not absorbed by suspension, box/materials, then the problem of "settling" time comes into play. Feedback would simulate a lower Q, thus beneficial.
The cost may not be higher at all, if the total Q of the entire speaker is optimized to absorb any excess energy, regardless of type, open, closed etc. That is why I suggest variable controls, at least one to adjust the total Q of the entire speaker. I do on mine, as Danny does, to optimize lower frequency accuracy.
All this helps in the seamless integration of woofer to mid and higher drivers.
cheers
steve
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Steve I understand andf xcan appriciate everything you said, but one thing is that most of us do not have your kind of talent or expeience and as such do not have access to the kind of hand tweaked eq
I understand and apologize if I come across in a poor way T, and others. Sometimes I feel that some ways of doing things get dumped on, when my own experiences say there is merit. I am also looking at what can be accomplished, pushing the borders of improvement.
cheers and no harm meant.
steve
Steve no apologies are necessary. (I should apologize for that mess of a post. I started to type something without reading it and then the phone rang and somehow I must have unintentionally hit the submit button. I'm kind of embarrassed that that mess ever made it onto the thread.)
You didn't come across in a poor way at all. The point that I was going to make, if I had finished the comment :roll:, was that while what you were talking about is perfectly valid within the world of your equipment, most of us out here do not have access to equipment like yours. While Danny's subs might not be beneficial to you and your gear, they could be just the ticket for some of us out here that have to rely on commercially available gear which does not incorporate the technology that you have in your system.
I was not in any way trying to knock anything that you had said, just raise the point that Danny's can be the right product for certain folks in certain situations. (Just for the record, while I have heard his subs I could not own them as even his smaller model is too big for the space I have to work with.)
And BTW, as a fellow engineer, I rather enjoy reading your posts. My career took me in a direction other than audio so I do not have anywhere near the expertise you have in the field. But I do have enough knowledge to follow and understand what you are talking about and your posts take things down to a level of detail that I quite frankly never really thought about before and I find them quite interesting. Please keep them coming.
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Steve I understand andf xcan appriciate everything you said, but one thing is that most of us do not have your kind of talent or expeience and as such do not have access to the kind of hand tweaked eq
I understand and apologize if I come across in a poor way T, and others. Sometimes I feel that some ways of doing things get dumped on, when my own experiences say there is merit. I am also looking at what can be accomplished, pushing the borders of improvement.
cheers and no harm meant.
steve
Steve no apologies are necessary. (I should apologize for that mess of a post. I started to type something without reading it and then the phone rang and somehow I must have unintentionally hit the submit button. I'm kind of embarrassed that that mess ever made it onto the thread.)
You didn't come across in a poor way at all. The point that I was going to make, if I had finished the comment :roll:, was that while what you were talking about is perfectly valid within the world of your equipment, most of us out here do not have access to equipment like yours. While Danny's subs might not be beneficial to you and your gear, they could be just the ticket for some of us out here that have to rely on commercially available gear which does not incorporate the technology that you have in your system.
I was not in any way trying to knock anything that you had said, just raise the point that Danny's can be the right product for certain folks in certain situations. (Just for the record, while I have heard his subs I could not own them as even his smaller model is too big for the space I have to work with.)
And BTW, as a fellow engineer, I rather enjoy reading your posts. My career took me in a direction other than audio so I do not have anywhere near the expertise you have in the field. But I do have enough knowledge to follow and understand what you are talking about and your posts take things down to a level of detail that I quite frankly never really thought about before and I find them quite interesting. Please keep them coming.
Thanks for your thoughtful reply T. I hope Danny does not think I was simply dicing his ideas, components etc. I am certain that most would certainly benefit from his expertise and products. I have heard great things about his products.
I certainly loved Danny's Myth of Speaker burn in webpage. It is that kind of research that moves the field forward.
Being in constant research mode certainly has its pluses, but also..... sometimes. I hope my research will inspire others to expand their concepts in their search for optimal reproduction.
cheers
steve
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My wife would just shrug her shoulders and say it is just part of the disease of being an engineer.
We can never leave anything well enough alone. :-k
I have a friend who lives out in Colorado who tells me there is a psychologist in her town whose practice specializes in dealing with the wives of engineers and helping them learn to cope with all of out idiosyncrasies. :rofl:
She is not one of his patients, but her husband is an engineer, so she appreciates the concept. :roll:
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Been a EE for 38 years. Has not changed one bit in the want to build stuff for repro of music. Hence the 6x12 servo sub arrays and hybrid line arrays.
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My wife would just shrug her shoulders and say it is just part of the disease of being an engineer.
We can never leave anything well enough alone. :-k
I have a friend who lives out in Colorado who tells me there is a psychologist in her town whose practice specializes in dealing with the wives of engineers and helping them learn to cope with all of out idiosyncrasies. :rofl:
She is not one of his patients, but her husband is an engineer, so she appreciates the concept. :roll:
I got a chuckle with that T. I don't see any problem with us. :rofl:
Dan, an audiophile, has helped out a lot. One time I told him of a tweak. His replay was
"NO! No more changes!"
Another time, though, I told him I think I am finished with tweaking. His reply was,
"No more changes? When pigs fly!"
What can we say T, it is in our DNA. :thumb:
cheers
steve
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What can we say T, it is in our DNA. :thumb:
Indeed it is. 8)
Check out Scott Adams thoughts on Engineering DNA:
https://www.youtube.com/watch?v=g8vHhgh6oM0
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My wife knew what she was getting into when we were dating and married me anyway. :lol: While not an engineer I definitely have the problematic "DNA". The only time it really gets on her nerves is when I can't leave a recipe alone and make it as written, instead of tinkering with it. Everything else is fair game without too much grumbling. With few exceptions it seems like just about everything could stand some improvement, the trick is to recognize the exceptions when they crop up.
Something about "if it ain't broke don't fix it".
Scotty
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What can we say T, it is in our DNA. :thumb:
Indeed it is. 8)
Check out Scott Adams thoughts on Engineering DNA:
https://www.youtube.com/watch?v=g8vHhgh6oM0
My sides are aching, LOL. That is hilarious T.
Scotty, sounds like you have a great wife.
Just a clarification, Dan is not the Danny here.
cheers
steve