it would have to be a low Le woofer in a sealed box. none of the ported speakers i've heard could reproduce real drums. sealed comes closer, but real drums have such fast and powerful impact even from very far distance. i've never heard speakers be able to do that.
i don't know why people defend ported. even ported "done right" has poor transient response and has that looseness. it makes drums sound like big low-frequency horns. i agree that for 2-way and MTM speakers, ported often sounds better than sealed due to its extension, but i don't understand why people would use ported for no-holds-barred speakers with big woofers.
i don't know why people defend ported. even ported "done right" has poor transient response and has that looseness. it makes drums sound like big low-frequency horns. i agree that for 2-way and MTM speakers, ported often sounds better than sealed due to its extension, but i don't understand why people would use ported for no-holds-barred speakers with big woofers.
cotdt said:
I thought so before, but now I more tend to feel it's what is not know that prevents 90% of the ported speakers from sounding right even if people think it's done the "right way". The only right way is when it sounds right within the physical limits, and you know exactly why and what physical limits are producing what effects.
soongsc, what do mean by physical limits? there aren't very much stuff on how to do ported right, which might be why i've never heard realistic ported bass. the stuff i've seen seem to suggest that it'll never have as good a transient response as sealed regardless of how it's done though. so i remain skeptical unless someone can show that you can also get great transient reponse with ported.
my next speakers will have phase/time correction, we'll see if it really helps or it's just hype based on overemphasizing theory.
my next speakers will have phase/time correction, we'll see if it really helps or it's just hype based on overemphasizing theory.
It can be done for sure and you gave the answer yourself which tools are needed:
It won't be easy.
Time correction can be taken as far as getting the same step response from a reflex-box as a closed one has. But this isn't a streightforward task (see group-delay measurement, red curve):
http://www.klein-hummel.com/html/studio/studio_index_e.htm
Regards
Charles
May I add a suggestion for a speaker? How about a Karlson??
Hi Bing
I have not read the whole post yet (I will later on), but I do have a suggestion that could get you waht you want. If you really want to feel the drums, build yourself a Karlson cabinet and load it with a good driver. Many have commented that this type of speaker does drums the best (do a search for Magnetar's posts- he has a pair that he uses with bass subhorns, and look for FreddyI here and on Audio Asylum- he is the real Karlson expert). Just one caveat- do not make the low-pass XO point higher than about 100Hz - 150Hz- cavity resonances make their nasty appearnace above that. Just and idea.
Enjoy,
Deon
Hi Bing
I have not read the whole post yet (I will later on), but I do have a suggestion that could get you waht you want. If you really want to feel the drums, build yourself a Karlson cabinet and load it with a good driver. Many have commented that this type of speaker does drums the best (do a search for Magnetar's posts- he has a pair that he uses with bass subhorns, and look for FreddyI here and on Audio Asylum- he is the real Karlson expert). Just one caveat- do not make the low-pass XO point higher than about 100Hz - 150Hz- cavity resonances make their nasty appearnace above that. Just and idea.
Enjoy,
Deon
G'd 'evvins! I'd forgotten all about the Karlsons. I remember that they did very well in their day; promoted heavily by Lafayette Radio (sigh) as a package with their sheepskin surround woofer. From the wild 'n' wooly days of high fidelity.
My experience is that ported can be just fine. It's trickier of course, being fourth order as opposed to second, but it does allow a bit more extension all other things being roughly equal.
I use a driver with a resonance around 20 Hz, Qts in the region of about .32, a large box, and tune the box to about 17 Hz. The Extended Bass Shelf alignment. It rolls off a little sooner than maximally flat configurations like the Butterworth, but maintains loading down to the resonance point, and at that point has more bass output than the Butterworth configuration. Any ported design causes the driver to be essentially unloaded below the box resonant frequency. (this can be helped a bit by using a resistive port, like the Variovent) If the enclosure resonant frequency is, say, 40 Hz, and the program material contains bottom octave content, why yes, there will be problems. In that case, a sealed design is probably the preferred configuration. A 5-8" driver that cannot hope to cover the full bottom octave should be considered for a sealed box, with approriate driver Qts.
There are many very successful commercial designs that have excellent bass and are ported. As with so many other design areas in this field, it's not so much that one approach or another is always superior, but that the selection and execution of the appropriate design choices for the given requirements is the key to success.
My experience is that ported can be just fine. It's trickier of course, being fourth order as opposed to second, but it does allow a bit more extension all other things being roughly equal.
I use a driver with a resonance around 20 Hz, Qts in the region of about .32, a large box, and tune the box to about 17 Hz. The Extended Bass Shelf alignment. It rolls off a little sooner than maximally flat configurations like the Butterworth, but maintains loading down to the resonance point, and at that point has more bass output than the Butterworth configuration. Any ported design causes the driver to be essentially unloaded below the box resonant frequency. (this can be helped a bit by using a resistive port, like the Variovent) If the enclosure resonant frequency is, say, 40 Hz, and the program material contains bottom octave content, why yes, there will be problems. In that case, a sealed design is probably the preferred configuration. A 5-8" driver that cannot hope to cover the full bottom octave should be considered for a sealed box, with approriate driver Qts.
There are many very successful commercial designs that have excellent bass and are ported. As with so many other design areas in this field, it's not so much that one approach or another is always superior, but that the selection and execution of the appropriate design choices for the given requirements is the key to success.
"Look in the time domain - vented boxes almost always have poorer transient response compared to sealed. i.e higher Q."
Not relevant; IMO Hales' was implying that ports give a sloppy underdamped response.
The difference between sealed and well designed (it is harder to do them right) ported systems are insignificant to the overhang that the room will have.
Not relevant; IMO Hales' was implying that ports give a sloppy underdamped response.
The difference between sealed and well designed (it is harder to do them right) ported systems are insignificant to the overhang that the room will have.
LilMik said:can the combination "206e in a horn" reproduce drums in a "realistic" way, so that drums actually sounds like drums?
have a nice day
lilmik
I really have to say again that: "No" Nothing can. Drums are impossible ro reproduce, bacause of their transints and wide range of frquencies. It depends HOW do you want your drums to sound. You really have to compromice.
hello,
hard to describe how i want the drums to sound.
well, everyone knows the sound of a typical 2way bookshelf speaker with a 6" woofer and a small dome tweeter with a 2nd order crossover at 2500. you can hear the drums, but there is something missing, it does not have any impact, a sounds not like a real drum, more like a small "toy-drum" for a kid. no power, no feeling, it sounds small and... well... tiny.
this is also true for every hifi-speaker i have heard: two way, three way, four way, whatever. also a big "no-waf-speaker" with two big 10" woofers from eton, two 6" mid-woofers from eton, a big midragen horn from jbl and a horn tweeter from e-voice, all active, could not bring drums to a level one could say that they have this "powerful" and "big" sound of a real drum.
what I want is a powerful, explosiv and big sound: if you hear the drums, you have to think that your ears are exploding. it does not have to be loud, that's not important for me. and i don’t think that the speaker has to go very deep, let's say under 50hz or so. but it has to sound powerful and explosiv and big. imho, these are the most important ascpects to reproduce drums in a way that let's you at least think you are listening to drums.
are pa-spakers the way to go? a professionel 12" woofer... or 15" woofer... or two 6” woofer… with a midrange-horn?
or does the woofer size not really matter that much and you only need the right woofer? look at the trappo mentioned earlier in this thread, it only has two 5 1/2" woofers. http://www.phio-audio.de/Trappo.html
what about altec's famous "voice of cinema"?
and... what about a 8" fullrangedriver (for example the 206e or the 208es) in a backloaded horn?
have a nice day
lilmik
hard to describe how i want the drums to sound.
well, everyone knows the sound of a typical 2way bookshelf speaker with a 6" woofer and a small dome tweeter with a 2nd order crossover at 2500. you can hear the drums, but there is something missing, it does not have any impact, a sounds not like a real drum, more like a small "toy-drum" for a kid. no power, no feeling, it sounds small and... well... tiny.
this is also true for every hifi-speaker i have heard: two way, three way, four way, whatever. also a big "no-waf-speaker" with two big 10" woofers from eton, two 6" mid-woofers from eton, a big midragen horn from jbl and a horn tweeter from e-voice, all active, could not bring drums to a level one could say that they have this "powerful" and "big" sound of a real drum.
what I want is a powerful, explosiv and big sound: if you hear the drums, you have to think that your ears are exploding. it does not have to be loud, that's not important for me. and i don’t think that the speaker has to go very deep, let's say under 50hz or so. but it has to sound powerful and explosiv and big. imho, these are the most important ascpects to reproduce drums in a way that let's you at least think you are listening to drums.
are pa-spakers the way to go? a professionel 12" woofer... or 15" woofer... or two 6” woofer… with a midrange-horn?
or does the woofer size not really matter that much and you only need the right woofer? look at the trappo mentioned earlier in this thread, it only has two 5 1/2" woofers. http://www.phio-audio.de/Trappo.html
what about altec's famous "voice of cinema"?
and... what about a 8" fullrangedriver (for example the 206e or the 208es) in a backloaded horn?
have a nice day
lilmik
The voice of the theater stuff from Altec is still highly praised today. It doesn't go deep, it doesn't go high but the stuff in the middle is sweet. If you can get your hands on a 416 or 515 woofer, either of those might suit your needs. Horn loading helps too. The difference between the Altec model 19 and the A7 is very noticeable.
Or, you can do what I did and get some Altec cabinets off ebay and load them with Selenium drivers. I can't imagine a regular woofer reproducing drums as well as a good PA driver.
Or, you can do what I did and get some Altec cabinets off ebay and load them with Selenium drivers. I can't imagine a regular woofer reproducing drums as well as a good PA driver.
I find drums over my dipoles quite realistic, and often stunningly realistic in fact, with a few caveats addressed below. It might have to do with the dipole nature of most drums in the first place.
Now the caveats:
- group delay. The problem with bookshelves etc lies not so much in the missing bass per se, but in the fact that the cutoff and associated group delay is too close to the frequency of the drums. Say if your speakers go down to 40-50 Hz (-3 dB) and you need a 60 or 80 Hz fundamental, as a sharp transient, then your group delay caused by the rolloff (worse if ported) will already have an effect in muddying the timing and thusly, the impact. Conclusion: cutoff should be well below the deepest frequency you want to reproduce, and ideally have a shallow rolloff (Q 0.5, 12 dB/oct).
- box resonances (energy storage) will have the worst effect when your signal is deep yet supposed to be sharp.
(both above points again speak for well done dipoles)
- room resonances. When I said that drums sound great on my dipoles (2x 10" woofers, 20 Hz cutoff -6 dB Q 0.5, at least by calculation, I don't trust my measurements in that range; 6.5" woofer XO at 100 Hz; dome tweeter XO 1600 Hz) I have to admit it depends on the fundamental. In some frequency ranges I have room resonances and nevermind that I use dipoles, everything sounds muddy if it falls in the resonance bands. Unfortunately my room has plenty of those: 100, 75 and 50 Hz are the worst offenders for me, and really exact notching out of those has eluded me so far.
- actual dynamics. Now here the recording comes in, with typically compression applied. So, compared to our (real) African drums tapped by our 18 months old, yes indeed, any recording sounds meager. but this to me seems an effect of raw dB just not being there. I don't believe it's the missing dynamics of the speakers, I believe it's usually not in the recordings in the first place. Why? Because ausiophile test CD's sound significantly better than typical commercial recordings.
Just my $0.02.
Now the caveats:
- group delay. The problem with bookshelves etc lies not so much in the missing bass per se, but in the fact that the cutoff and associated group delay is too close to the frequency of the drums. Say if your speakers go down to 40-50 Hz (-3 dB) and you need a 60 or 80 Hz fundamental, as a sharp transient, then your group delay caused by the rolloff (worse if ported) will already have an effect in muddying the timing and thusly, the impact. Conclusion: cutoff should be well below the deepest frequency you want to reproduce, and ideally have a shallow rolloff (Q 0.5, 12 dB/oct).
- box resonances (energy storage) will have the worst effect when your signal is deep yet supposed to be sharp.
(both above points again speak for well done dipoles)
- room resonances. When I said that drums sound great on my dipoles (2x 10" woofers, 20 Hz cutoff -6 dB Q 0.5, at least by calculation, I don't trust my measurements in that range; 6.5" woofer XO at 100 Hz; dome tweeter XO 1600 Hz) I have to admit it depends on the fundamental. In some frequency ranges I have room resonances and nevermind that I use dipoles, everything sounds muddy if it falls in the resonance bands. Unfortunately my room has plenty of those: 100, 75 and 50 Hz are the worst offenders for me, and really exact notching out of those has eluded me so far.
- actual dynamics. Now here the recording comes in, with typically compression applied. So, compared to our (real) African drums tapped by our 18 months old, yes indeed, any recording sounds meager. but this to me seems an effect of raw dB just not being there. I don't believe it's the missing dynamics of the speakers, I believe it's usually not in the recordings in the first place. Why? Because ausiophile test CD's sound significantly better than typical commercial recordings.
Just my $0.02.
It has been along time since I have seen a live band (kids,work ,etc).I was walking past somebody practising in an empty school.The sound of an unamplified drum kit sounded so different to anything I have heard off the hifi ,there was no comparison.My speakers have 15"bass units in a 135 litre Onken so there is no lack of lower bass,maybe I should install a PA system and enjoy a single life.
The things to blame for poor drum reproduction are:
1- Room acoustics together with speaker wide dispersion patterns. You are not hearing one drum, you are hearing a dozen of out-of-phase drums, one coming from the speaker and the rest coming from the walls with similar intensity (note that delayed out of phase transients tend to cancel mutually).
2- Poor crossover design, that leads to speakers that radiate more coherent sound towards the walls than towards the listening position in the cross-over regions.
However, non-sense audiophile-market trends impose as wide as possible dispersion patterns and on-axis sound cancellation to obtain that "sound coming of everywhere" effect that dumb audiophiles love so much (actually made up by lots of delayed copies of the original sound coming from the walls, floor and ceiling and cancelling mutually!!!)
Horns solve most of the directivity problem, as the sound coming from the walls is weak enough to avoid substantial interaction with the main on-axis radiation. However, making two or three-way horn systems to sum properly on-axis in the crossover region is a quite difficult task (requiring custom filters and phase shifters). And if it does not sum on-axis, it will sum off-axis leading to the same problem as with direct radiators...
Also, the clever owner of the following website has a great understanding of the problem with room acoustics and direct radiators, and he solves it quite well just with open baffles, whose back radiation cancels most of the front radiation before it can reach the walls, floor and ceiling (altough he doesn't tell a word about that trick): http://www.linkwitzlab.com/
1- Room acoustics together with speaker wide dispersion patterns. You are not hearing one drum, you are hearing a dozen of out-of-phase drums, one coming from the speaker and the rest coming from the walls with similar intensity (note that delayed out of phase transients tend to cancel mutually).
2- Poor crossover design, that leads to speakers that radiate more coherent sound towards the walls than towards the listening position in the cross-over regions.
However, non-sense audiophile-market trends impose as wide as possible dispersion patterns and on-axis sound cancellation to obtain that "sound coming of everywhere" effect that dumb audiophiles love so much (actually made up by lots of delayed copies of the original sound coming from the walls, floor and ceiling and cancelling mutually!!!)
Horns solve most of the directivity problem, as the sound coming from the walls is weak enough to avoid substantial interaction with the main on-axis radiation. However, making two or three-way horn systems to sum properly on-axis in the crossover region is a quite difficult task (requiring custom filters and phase shifters). And if it does not sum on-axis, it will sum off-axis leading to the same problem as with direct radiators...
Also, the clever owner of the following website has a great understanding of the problem with room acoustics and direct radiators, and he solves it quite well just with open baffles, whose back radiation cancels most of the front radiation before it can reach the walls, floor and ceiling (altough he doesn't tell a word about that trick): http://www.linkwitzlab.com/
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