I tried to intergrate subs with my hi fi for music and have never really been been impressed. phase issues/ muddy botom en etc.
In many of the large PA's that I work with most of the bottom end energy appears to appeary lie above 40 hz.
The best sub I have tried with my stereo for music was designed by Silicon Chip about eight years ago (Bass Barrel)
I used to have a realitlvely small compound isobaric bandpass sub that used a pair or 6.5 inch drivers. This thing punched really hard. As the enclosure is tuned it has a built in lo pass without a crossover. I did use one though
Its not to hard to design such enclosures with a program such as bass box pro. Add a electronic crossover and a good power amp and you can have a flexible x over point at a realatively low cost.
Phase is The main problem subs intergrating with HI Fi's if its out no matter where you place the sub or how much it costs things wont work properly.
Bear this in mind also; sometimes subs work better 180 deg out. you will have to experiment.
There is a simple calculating program where you put in your room dimentions in and it tells you the room nodes and resonances. I dont know what it is called but a friend has it very handy for studio/ listening rooms.
Cheers.
Dont quote me on this but some of this advice could help.
In many of the large PA's that I work with most of the bottom end energy appears to appeary lie above 40 hz.
The best sub I have tried with my stereo for music was designed by Silicon Chip about eight years ago (Bass Barrel)
I used to have a realitlvely small compound isobaric bandpass sub that used a pair or 6.5 inch drivers. This thing punched really hard. As the enclosure is tuned it has a built in lo pass without a crossover. I did use one though
Its not to hard to design such enclosures with a program such as bass box pro. Add a electronic crossover and a good power amp and you can have a flexible x over point at a realatively low cost.
Phase is The main problem subs intergrating with HI Fi's if its out no matter where you place the sub or how much it costs things wont work properly.
Bear this in mind also; sometimes subs work better 180 deg out. you will have to experiment.
There is a simple calculating program where you put in your room dimentions in and it tells you the room nodes and resonances. I dont know what it is called but a friend has it very handy for studio/ listening rooms.
Cheers.
Dont quote me on this but some of this advice could help.
Dave,
I have read your posts on many occasions discussing your dislike for MDF. I think the most commonly cited problem with MDF is it's tendencies in terms of energy storage. Can you discuss how the use of MDF impacts performance in a subwoofer specifically, preferably with objective data to support your case? This is not to say that I think you're wrong, but rather that MDF is a reasonable approach in terms of a balance between performance and price when used for a subwoofer, whereas the energy storage is certainly a concern of mine when used for a cabinet for full range use, particularly in the midrange.
Your thoughts? I hate to re-hash such a frequently discussed topic, but saw an opportunity. You can pm me if you'd like and spare this thread.
To stay relatively on topic, I do not totally agree with Zaph regarding Xmax. It is as much about the application as it is the product. Naturally, more Xmax is required to reach a given level of output in a sealed/IB or even dipole application, whereas the addition of a Helmholtz resonator (or a passive radiator that behaves as such) significantly reduces the amount of Xmax that is required. It should also be noted that not all Xmax is identical; a standard overhung design with the same-old 10mm top plate and no gap or copper treatments is in no way similar to any method that employes a linear BL approach, whether it's LMT, XBL^2, or Split Coil. One must be cautious to avoid painting with a too broad brush. For example, though high inductance is often considered a negative, it's effects in the subwoofers bandwidth is relatively limited and the benefits of less BL based distortion far outweighs the downsides of higher inductance, in my opinion.
Also, to the poster who asked about eD, they seem to have made improvements in both customer service and product offerings, but there are still many who will never go back to them for a variety of issues that have occurred over the last 4 or 5 years.
I have read your posts on many occasions discussing your dislike for MDF. I think the most commonly cited problem with MDF is it's tendencies in terms of energy storage. Can you discuss how the use of MDF impacts performance in a subwoofer specifically, preferably with objective data to support your case? This is not to say that I think you're wrong, but rather that MDF is a reasonable approach in terms of a balance between performance and price when used for a subwoofer, whereas the energy storage is certainly a concern of mine when used for a cabinet for full range use, particularly in the midrange.
Your thoughts? I hate to re-hash such a frequently discussed topic, but saw an opportunity. You can pm me if you'd like and spare this thread.
To stay relatively on topic, I do not totally agree with Zaph regarding Xmax. It is as much about the application as it is the product. Naturally, more Xmax is required to reach a given level of output in a sealed/IB or even dipole application, whereas the addition of a Helmholtz resonator (or a passive radiator that behaves as such) significantly reduces the amount of Xmax that is required. It should also be noted that not all Xmax is identical; a standard overhung design with the same-old 10mm top plate and no gap or copper treatments is in no way similar to any method that employes a linear BL approach, whether it's LMT, XBL^2, or Split Coil. One must be cautious to avoid painting with a too broad brush. For example, though high inductance is often considered a negative, it's effects in the subwoofers bandwidth is relatively limited and the benefits of less BL based distortion far outweighs the downsides of higher inductance, in my opinion.
Also, to the poster who asked about eD, they seem to have made improvements in both customer service and product offerings, but there are still many who will never go back to them for a variety of issues that have occurred over the last 4 or 5 years.
DevilDriver said:
Instead of repeating myself, there is a thread, "another discussion on what to build speaker out of" or some such...
Particularily for a subwoofer, plywood is better. If you want best cheap/performance compromise them particle board is the winner. Cheaper than MDF and better (at least sonically -- it is harder to work with -- the prime reason manufacturers would like you to think MDF is the material...)
dave
doorman said:
I work with CNC router and milling equipment every day for a company that makes mainly industrial use transport boxes but also the occasional speakers and flightcases, and as a professional in the field I can safely say that the fine dust that MDF produces is actually one of the reasons why it's so popular in the industry, simply because it's low grainular weight makes it more easily extracted by the suction system.
The higher price of MDF is in most cases completely counterweighted by this easier waste management in comparison to other particle board types.
Off course, we mainly use plywood, in particular spruce ply because of it's superior price to quality ratio (and it's availability in extremely large quantities) but in cases were maximum stability is wanted, we use birch ply instead.
Saturnus said:
For the record, at least according to the equal loudness curves I've seen, the threshold at 20 Hz is closer to 75 dB.
JWilliams said:
True. I meant at 10 Hz. Sorry for the typo. Double typo even. And although the threshold of human hearing is around 74 db at 20 Hz, according to my audiologist friend which participated in the studies referred to in the article, it'll take around 94 db at 20 Hz to rise above background level in a normal urban area.
Here is a good thread with various 18s that people are using in diy: http://www.avsforum.com/avs-vb/showthread.php?t=876127
I personally have a pair of Ascendant Audio Avalanche 18" each in 25 cubic foot sonotubes tuned to 14 Hz. They are impressive to say the least, with movies things are definitely felt and pressurized.
There are a bunch of movies that have frequencies below 20 Hz. http://www.avsforum.com/avs-vb/showthread.php?t=656467&highlight=movies+that+don't+suck
Try it, if you don't like it then sell them. I can't imagine doing without mine now.
I personally have a pair of Ascendant Audio Avalanche 18" each in 25 cubic foot sonotubes tuned to 14 Hz. They are impressive to say the least, with movies things are definitely felt and pressurized.
There are a bunch of movies that have frequencies below 20 Hz. http://www.avsforum.com/avs-vb/showthread.php?t=656467&highlight=movies+that+don't+suck
Try it, if you don't like it then sell them. I can't imagine doing without mine now.
Daveis said:
Correction...
1) The lowest note on "a" pipe organ is 8Hz. Any stopped 32' pipe or open 64' pipe will give you a very solid 8Hz that you can definately feel. Or you can play two 32' Double Open stops in 5th's, and produce an 8Hz tone caused by the two 5th tones "beating" against one another. That would be called a 64' Resultant.
2) I have quite a few CD's that have plenty if bass well below 20Hz, including classical, pop, darkwave, goth, rock, etc, etc. Trust me, if you have the system to reproduce it properly, you'll know that the sub-20Hz information is there.
3) Below 20Hz is very useful, especially with movies. The final helicopter crash in The Day After Tomorrow where the fuel in the lines freeze, there's significant information down to 10Hz. There are quite a few scenes in War Of The Worlds, The Incredibles, Spiderman (I & II), etc, etc, etc that have significant information down to 10Hz, even 5-7Hz in some areas.
4) Come over sometime and I'll play Flight Of The Phoenix where the plane gets caught in the sand storm, rolls a couple of times and crashes. Durring the rolls, there's plenty of very significant, very strong bass at and below 15Hz sustained for at least 10+ seconds, and you can easily hear and feel it. If you can't at least feel it, you must be dead.
So, to get back to the original question... YES, 10-25Hz is very necessary, both for music and movies. At least it is for me.
Just my 2 cents.
chops said:
So, to get back to the original question... YES, 10-25Hz is very necessary, both for music and movies. At least it is for me.
Just my 2 cents.
Hi,
just to add my 2 cents for those suggesting music (not movies) does
not need anything below low E on as bass (41Hz), for music around
28Hz up is more important than anything below 28Hz IME.
Low E (41Hz) is not good enough for good kick drum, whilst low B (31Hz) is.
Going half an octave below 41Hz is good Bass IMO, going say
another half an octave to 20Hz is an expensive business for
the reward on music, not that there is anything wrong with it.
/sreten.
sreten said:
Hi,
just to add my 2 cents for those suggesting music (not movies) does
not need anything below low E on as bass (41Hz), for music around
28Hz up is more important than anything below 28Hz IME.
Low E (41Hz) is not good enough for good kick drum, whilst low B (31Hz) is.
Going half an octave below 41Hz is good Bass IMO, going say
another half an octave to 20Hz is an expensive business for
the reward on music, not that there is anything wrong with it.
I disagree.
For one thing, there are more synthesizer/electronic sounds in recordings that can and do go well below 41Hz or 31Hz. And I'm not talking about that rap or drum & bass garbage either. I'm referring to regular music. Yanni, Enya, Enigma, Depeche Mode, Kate Bush, Pink Floyd, Metallica, etc, etc... Heck, even Boston's Third Stage back in the late 70's all have bass information around or below 20Hz.
Not only that, but a lot of recording studios use equipment that will reproduce the original sound an octave lower to add more punch and feel into the music, or to make it a bit more dramatic.
Also, with live recordings in churches, music halls and the like, the actual venue itself can have significant bass energy below 20Hz simply due to the natural acoustics of the environment, whether it be due to outside traffic or the heating/cooling system of the building.
Why is this important in recordings? Well, it gives you a sense of size and dimension of the original recording venue, making you feel like you are there. Believe it or not, it really does add to the recording.
If your system is incapable of reproducing this sub-20Hz information, then you're missing out on some really good stuff.
chops said:
Hi,
Your post is not addressing the point of my post.
Going from 41hz cut off to 28hz makes a huge difference, much
more than going another half octave to 20Hz, perhaps the same
as going a further octave. My point is going the first half octave
is the most important, the 2nd, 3rd, 4th progressively less so.
For music the cost of achieving audible levels of progressively
lower bass has to hit a cost vs effectiveness issue that is
different to movies and I'll stick by my guns.
Good bass down to 28Hz on music sounds awesome compared
to down to 41Hz, but like I said nothing wrong with going lower,
just it becomes an expensive business for every tone (1/6 octave)
you want to go lower.
/sreten.
Sure it's addressing your point.
You're saying that 28Hz extension is enough, and I'm saying it's not. Oviously, neither one of us are right or wrong as they are just our opinions.
And as for building a subwoofer capable of reaching below 20Hz does NOT have to be "an expensive business". Of course, that also depends on what is expensive to you.
To me, spending $250 on a pair of Dayton 15" DVC drivers, $500 on a Crown XTi 1000 amp and $30 on .75" MDF, screws, glue and silicone to build a 6.3cf sealed push-pull subwoofer that has effective output down to around 12-14Hz (in my room) and still be very musical is not expensive.
You're saying that 28Hz extension is enough, and I'm saying it's not. Oviously, neither one of us are right or wrong as they are just our opinions.
And as for building a subwoofer capable of reaching below 20Hz does NOT have to be "an expensive business". Of course, that also depends on what is expensive to you.
To me, spending $250 on a pair of Dayton 15" DVC drivers, $500 on a Crown XTi 1000 amp and $30 on .75" MDF, screws, glue and silicone to build a 6.3cf sealed push-pull subwoofer that has effective output down to around 12-14Hz (in my room) and still be very musical is not expensive.