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anox3
05-10-2004, 05:06 PM
With speakers in general, Is there a large diffrence in frequency response between 36 and 38Hz? Does the Hz refer to the bass or highs?

swampcat
05-10-2004, 06:24 PM
You'll never hear the difference of 2 hz. Listen to the speakers see what sounds better, what speaker do you prefer. Dont worry about the difference of 36 hz versus 38 hz. You may find the speaker with the 38 hz spec much more desirable and may not. You may listen to a speaker with a 40 hz rating that sounds much better than iether the 36, 38 hz spec. To minor to worry about. Go with what sounds good to you. You can and should listen to some advice about certian speakers ,but it has to sound good to you and only you! Listen to many speakers, even ones you could only dream of owning, to get the different sounds and then decide.

poneal
05-10-2004, 06:26 PM
The Hz refers to the lower frequencies. There is not much recorded below 40Hz on musical recordings. DVD movies are the ones that use the lower octaves for stun effects.

swampcat
05-10-2004, 06:29 PM
With speakers in general, Is there a large diffrence in frequency response between 36 and 38Hz? Does the Hz refer to the bass or highs?

The 36-38hz refers to bass response and 20khz refers to highs (20,000 hz) To minor to worry about.

N. Abstentia
05-10-2004, 07:32 PM
Also speaker companies rate their speakers differently. Low end stuff can be rated with a higher tolerance of variation and distortion so in fact a speaker rated to go down to 38 hz could in fact be outperformed by a speaker rated to go down to 45 hz. The rating by itself means nothing at all, you have to know how exactly it was measured.

RGA
05-10-2004, 10:53 PM
As the other s note if all else is equal the 36hz has more bass than 38hz - but all else is not equal. You need to know things like the =/-db rating - how was it recorded in a real room or an anechoic chamber - what is the distortion like? It's all nice to produce 36hz in a real room but if the bass is bloomy or boomy what good is it?

Most music is not recorded below 40hz. In fact the range of audible hearing for many many years was said to be between 40hz and 15khz. Most people still cannot hear beyond that and a reason so many tape decks were rated no better. Some people turned out to be able to hear out to around 18khz and of course you can feel bass below 40hz so they expanded the rating to 20hz to 20khz.

I have seen $99.00 Sony speakers with that rating but it means nothing. It may produce 20hz at -50db but you will not hear it in relation to other frequencies while playing music. the db rating of -6db at 40 hz for instance means that when a note is played at 40hz it will be 6 decibals quieter than the the midrange frequencies say 700hz to 1khz. But i have heard speakers thare rated there and are -3db which means you should hear the bass more but none of this talks about volume level. A lot of speakers sound thin when the volume goes up - others do not. So what SPL are they doing the test at - seriously doubt at 95db.

The frequency ratings really don't help - if you listened to my Wharfedales versus many slim line designed speakers which are rated into the 20's you would have zero doubt that my Wharfedales will produce its bass at louder levels with harder hitting impact and dynamics - though the other speaker may produce a deeper bass at low volumes. It also helps the high efficiency makes it easier on the amplifier to produce the levels.

Interestingly my AN-K standmount is rated to 36hz in a corner which as a rating is deeper than my Wharfedales - but the Wharfedales will have it at far higher volume levels that the K cannot likely get too. But because the K is new for me I don't want to risk pushing them too too much - one thing is for certain the K is far superior in bass distortion and distortion in general -

So is it good quality bass you want or deeper crappy bass --- deep crappy bass can be bought anywhere faiirly cheap - starting with the car audio industry - they specialize in deep crappy bass.

Actually the volume level is key because when I was out looking at subwoofers not long ago most are rated around 30hz and these were huge Velodyne subs with 100watt+amps and i was cratching my head thinking "but a real subwoofer is supposed to be SUBSONIC" which means below 20hz. Basically these subs are just woofers in a box and don't go very deep. But of course why they are so useful is that they can play 30hz much louder than your average floorstander rated to 30hz.

vivisimonvi
05-11-2004, 12:09 AM
Some CV speakers are very dynamic at any volume (you have to actually like them of course). Mine are the E715 model. I listen to a lot of music that pushes the frequency limits (I would guess in the low 30Hz range, probably lower), also, any DVD movie with no fear of damage. Out of curiousity this morning I played a CD (Skinny Puppy, TGWOTR) at high volumes measuring a little over 110 dB's from my SPL meter about a meter away with no sense of distortion or lack of definition (not for too long of course as you'll suffer permanent hearing damage).

I have a test tone program that produces sound in sine waves as well. My SVS 25-31 PCi sub sounds better at 25 Hz than my CV floorstanders at that same frequency. As other posters stated just because speakers are rated down to 20 Hz doesn't mean they're that very effective in that range (at least not very loud of course). You won't acheive over 90 dB's of pressure in the 20's with most speakers, as the lower you get the more accoustic energy is required.

FLZapped
05-11-2004, 04:41 AM
With speakers in general, Is there a large diffrence in frequency response between 36 and 38Hz? Does the Hz refer to the bass or highs?

Hertz is a basic frequency unit - essentially it means cycles per second and applies to all non-DC frequencies(you know, battery power).

The difference between 36 and 38 Hz is meaningless by itself other than it being two cycles per second difference. In speakers, one must also consider the type of enclosure used as they act like high-pass filters(barring bandpass designs) with varying degrees of rolloff slope based on their design. Of course, your room and speaker placement will modify the frequency response as well.

-Bruce

skeptic
05-11-2004, 06:56 AM
The generally accepted meaning today of this specification for a loudspeaker system is the frequency at which the speaker's acousitcal output in the bass is reduced by 3db (half the power output) at low frequencies relative to a 1 khz (midrange) frequency given the same level of electrical power input. This implies how low a freqeuncy the speaker will usefully reproduce. Unfortunately, it often implies more than it really means. These measurements are taken using a calibrated microphone, often at low power levels in a specially built echoless room called an anechoic chamber. In a real room, the results will vary all over the place so it is only a starting figure of merit for comparison but cannot be taken to the bank as a definitive measure of a speaker's bass performance.

Other pertinent factors they usually don't tell you is how much distortion there will be, how fast the response falls off below that frequency, and how loud the bass driver called the woofer will play before severe distortion occurs. Room acoustics and speaker placement also play a major role in bass performance. Ironically, smaller rooms such as those most common in homes don't provide the low frequency acoustical bass reinforcement larger rooms do where live music is commonly performed. This is strictly due it their relatively small dimensions.

Bass performance is VERY VERY important in music. It is what gives drums their thwack and impact. It is what gives a symphony orchestra its sense of power. It is critical to any music written for pipe organ. It is necessary for accurate musical timbre of pianos, cellos, double basses, tubas, and even bassoons. All electronically synthesized music uses very low tones and so does pop music using an electric bass. Sound systems which cannot accurately reproduce very low tones sound thin, less powerful, and have less impact than those that do. These low tones and drum beats are often used in music to convey rhythm, one of the critical elements of music. The loss of the impact of rhythm is no more missed anywhere than in the enjoyment of jazz music. Listening to recordings of jazz without the aspect deep bass brings to it is disappointing and boring compared to live performances.

For technical reasons, it was very difficult to record these deep tones on vinyl phonograph records and many turntables produced so much rumble and /or were so sensitive to acoustic feedback that systems capable of producing very deep bass created new problems even when those tones were not present. However, cds changed all of that and cds are easily capable of recording and reproducing tones to the lowest limit of human hearing, usually considered to be 20 hz and well below where vibrations are felt rather than heard.

Unfortunately, reproducing accurate very deep bass is one of the most expensive aspects of sound reproduction systems. IMO, most sound systems including so called high end systems frankly aren't up to it. Subwoofers can help if they are of very high quality and used with a great deal of skill and intelligence. Again, this is the rare case. Properly integrating a separate subwoofer with the rest of a sound system presents many difficulties for the experienced listener and requires a great deal of experimentation. Personally, I don't consider any loudspeaker product which does not make a serious attempt to reproduce the lowest tones to be high end no matter what other claims they make or virtues they have. The exceptions are full range electrostatic and magnetoplanar speakers where limited bass is inherent in their principle and the buyer knows going in what additional problems he is faced with.

RGA
05-11-2004, 06:40 PM
"The exceptions are full range electrostatic and magnetoplanar speakers where limited bass is inherent in their principle and the buyer knows going in what additional problems he is faced with."

Interesting and people buying standmounts with the HUGE HUGE advantage they offer over ANY and ALL floorstanders don't get credit for being buyers who know what they're going into and "what additional problems he is faced with[?]"

FLZapped
05-12-2004, 09:09 AM
The generally accepted meaning today of this specification for a loudspeaker system is the frequency at which the speaker's acousitcal output in the bass is reduced by 3db (half the power output) at low frequencies relative to a 1 khz (midrange) frequency given the same level of electrical power input.

A few use -10dB in some of their literature, so it is important to read it carefully!


Subwoofers can help if they are of very high quality and used with a great deal of skill and intelligence. Again, this is the rare case.

The majority of subs(especially HT types) I have seen all have large peaks around 80-100Hz. Few actually attempt to extend the bass range into the lowest octaves, instead looking to maximize those "thump" fequencies found in most modern music. In my opinion, this actually aggravates the ability to achieve proper room placement.

-Bruce

skeptic
05-12-2004, 09:33 AM
There are however, some very fine dedicated subwoofers such as the best models made by Velodyne using accelerometers in a feedback loop. Loudspeaker of any type whether called subwoofers or not that can accurately reproduce the lowest octave at reasonably high volume with low distortion are few and far between and usually very expensive. But they do exist.

The problem with integrating them with "satellite speakers" is in the transition range. In a well designed sound system, the low frequency unit makes a reasonably seamless match in both phase and frequency response. However when one subwoofer in one location is used with two satellites several feet away, they often created very irregular phase and frequency response that is exaggerated with peaks and troughs all over the place. The best way to use subwoofers IMO, it to buy two of them and locate each one as close to a satellite as possible. This in effect is what you get if you buy a full range tower system such as JBL S412p or recently available AR1.

The test of deep bass are organ pedal notes. Digital recordings on cd work best. On a real pipe organ, those notes are very deep, pure, and are felt. There are very few loudspeakers in my experience which can duplicate those tones accurately.

I think it is outrageous that a manufacturer sells you a pair of supposedly high fidelity loudspeakers for $1500, $2000, $2500 or even more and then tells you if you want to hear the bottom octave, go out and buy my subwoofer for another $1000 or more. That stinks.

One of the most frustrating things about deep bass is not only speaker placement but listener placement as well. Moving the speaker several inches can make a big difference in what you hear. So can moving to another spot in the same room.

vivisimonvi
05-12-2004, 03:38 PM
One of the most frustrating things about deep bass is not only speaker placement but listener placement as well. Moving the speaker several inches can make a big difference in what you hear. So can moving to another spot in the same room.

I couldn't agree more. The most frustrating part is that the best spots for deep bass are in the places you never seem to want to stand (or sit) in. I've tried just about every possible spot for my sub to satisfy my ONLY listening position (front and center of course).

RGA
05-12-2004, 05:53 PM
There are however, some very fine dedicated subwoofers such as the best models made by Velodyne using accelerometers in a feedback loop. Loudspeaker of any type whether called subwoofers or not that can accurately reproduce the lowest octave at reasonably high volume with low distortion are few and far between and usually very expensive. But they do exist.

The problem with integrating them with "satellite speakers" is in the transition range. In a well designed sound system, the low frequency unit makes a reasonably seamless match in both phase and frequency response. However when one subwoofer in one location is used with two satellites several feet away, they often created very irregular phase and frequency response that is exaggerated with peaks and troughs all over the place. The best way to use subwoofers IMO, it to buy two of them and locate each one as close to a satellite as possible. This in effect is what you get if you buy a full range tower system such as JBL S412p or recently available AR1.

The test of deep bass are organ pedal notes. Digital recordings on cd work best. On a real pipe organ, those notes are very deep, pure, and are felt. There are very few loudspeakers in my experience which can duplicate those tones accurately.

I think it is outrageous that a manufacturer sells you a pair of supposedly high fidelity loudspeakers for $1500, $2000, $2500 or even more and then tells you if you want to hear the bottom octave, go out and buy my subwoofer for another $1000 or more. That stinks.

One of the most frustrating things about deep bass is not only speaker placement but listener placement as well. Moving the speaker several inches can make a big difference in what you hear. So can moving to another spot in the same room.

I don't disagree because I too believe that you need two subwoofers. I often hear people tout subs as non-directional bass which may be but why do I always know where the sub is? And that was after parametric EQ set-up with SPL and test discs. It just does not sound quite right - can be good mind you for home theater because I don't have a reference for what a tanker truck is supposed to sound like when it explodes. An organ is another matter.

If you look at the Gershwin X1 and SW 1 this is a but the top half add the bottom later http://www.gershmanacoustics.com/sw1.html

And I agree bass costs lots of money. And unfortunately Skeptic we're all not as deep pocketed as you are. We are forced to make a concession - and that concession has to bass. You can add bass later - you can't fix the midrange so we can buy some $400.00 JBL or Cerwin Vega that has bass but it sounds like a complete mess everywhere else.

And my complaint about one sub aside you can buy one and then get the proper stereo balance back later again with another identical subwoofer. In my set-up I could have two subwoofers sit between my stanmounts almost right under them - or have them in a corner right behind the standmounts.

You can complain about the pricing but we have to compare apples to apples of what is out there. I personally think the entire industry is grossly overpriced. My dad worked as a purchasing agent for a sheet metal manufacturer and also sold to car companies. They also sold a lot of the parts to GM specifically. Sheet metal is still relatively cheap - there is no more than 30 hours of total labour on ANY production Toyota no Tercel or their 60k model. What you pay for is their expertise and machinary to put it together. I can go get the parts and it might take 5 years fro me to build it because i would have to take some mechanics courses. Speakers and all other products are in the same boat.

Thanks to a very few companies like Audio Note who you can buy a kit from and save yourself 50-80% -- which you may still say is high - but B&W doesn't even offer the option.

Woochifer
05-12-2004, 07:17 PM
I don't disagree because I too believe that you need two subwoofers. I often hear people tout subs as non-directional bass which may be but why do I always know where the sub is? And that was after parametric EQ set-up with SPL and test discs. It just does not sound quite right - can be good mind you for home theater because I don't have a reference for what a tanker truck is supposed to sound like when it explodes. An organ is another matter.

I don't think that applies in all cases. Typically, the recommendation to go with two subwoofers is when you got a large room that needs more bass reinforcement; but, in general larger rooms pose less significant acoustical challenges in the low frequencies, so depending on the sub, a single subwoofer in a large room might sound even better than in a smaller room and its inherent acoustical problems.

Perhaps you know where the sub is located because you got your eyes open. A friend of mine once claimed he could pick out the location of somebody's subwoofer, and he kept pointing to the subwoofer's spot even though in that session the subwoofer wasn't even switched turned on. Oh, what an ego bruising that was when he found out later on.

When you mention that a subwoofer setup still does not sound right "after parametric EQ setup with SPL (meter? SPL just means sound pressure level) and test discs" do you know what the crossover setup was and whether the bypass, delay timing, and phase settings were done correctly? And was this a two-channel setup that used the subwoofer's crossover in concert with either the speaker output or the premain outputs, or was it a multichannel setup where the processor/receiver handled the bass management? And unless you actually did the parametric EQ setup yourself, how do you know it was all done correctly to begin with? (unless you're using a RTA, correctly setting up the parametric filters with a SPL meter and test discs will take you at least an hour)

In a small-to-medium sized room, all of those factors have to be done correctly if you want the bass to be truly nondirectional. My own experience is that using subwoofer with a parametric EQ, SPL meter, and test discs can produce well integrated bass that's deeper and more linear than you can possibly get by just placing a set of standmounts somewhere in the room. Even with my receiver's relatively high crossover frequency of 90 Hz, the location of my subwoofer only occasionally gives itself away.

If you're trying two subwoofers in a small to medium sized room, good luck trying to correct for the room-induced problems. As much time as it takes to use a parametric EQ with one sub, there's much more trial and error with two subs.