Floorstanding vs. bookshelf + sub

[audio amateur]

Subwoofers can be set fairly high, into the frequency range already covered by a pair of small monitors... In my experiences (so far) with SUB/Monitor combos, the sub tends to dominate the proceedings and just makes itself too obvious... It reminds me of when you press the Extra Bass button on a cheapy mini-system... suddenly even songs that were not bass heavy sound like the belong on a Dr Dre album... Maybe one day I'll hear a properly integrated sub/monitor combo that will change my mind... but so far I've just not been impressed...

Subs need time to be set up in order to integrate properly. It's a long exercise, and is easier done in pairs. But IMO the end result can be very good. I'm guessing you've never heard a good quality sub that was set up properly for stereo listening.

[Luvin Da Blues]

[QUOTE=audio amateur]........It's a long exercise, and is easier done in pairs. But IMO the end result can be very good.....[QUOTE]

Very Very good indeed but "a long exercise" is an understatement.

[Kevio]

I tried two positions and three crossover settings and a bit of diddling with the level and all is good now for me. There's a bit more to it than setting up a stereo pair but its fun and didn't seem to take too long for me. Perhaps I'm just lucky.

One thing I did not appreciate going in to this is that although my mains gave me a satisfying amount of low frequency output, they also put out a fair amount of distortion in doing so. Now that they're being helped by the sub, I've got a much cleaner bottom end

[audio amateur]

I tried two positions and three crossover settings and a bit of diddling with the level and all is good now for me. There's a bit more to it than setting up a stereo pair but its fun and didn't seem to take too long for me. Perhaps I'm just lucky.

One thing I did not appreciate going in to this is that although my mains gave me a satisfying amount of low frequency output, they also put out a fair amount of distortion in doing so. Now that they're being helped by the sub, I've got a much cleaner bottom end

You mean that your mains are now high-passed? Or does it mean you play them less loud now that you have the subs?

[02audionoob]

Although I will decline to comment on how clean a bottom end I have, I will agree it's a bit a challenge to get a sub really sounding good. I tinker with it quite a bit in search of optimum. Right now, I have the port plugged up with a small towel. I might actually stick with that...not sure yet.

[Kevio]

You mean that your mains are now high-passed? Or does it mean you play them less loud now that you have the subs?

Yes, mains are high passed. I play at the same overall level as before. Maybe a little louder because it sounds better now.

[Ajani]

Although I will decline to comment on how clean a bottom end I have, I will agree it's a bit a challenge to get a sub really sounding good. I tinker with it quite a bit in search of optimum. Right now, I have the port plugged up with a small towel. I might actually stick with that...not sure yet.

You plugged a dirty bottom with a small towel? uggggg

[02audionoob]

You plugged a dirty bottom with a small towel? uggggg

It's better than having a muddy bottom end.

[audio amateur]

Yes, mains are high passed. I play at the same overall level as before. Maybe a little louder because it sounds better now.

If I may ask, how is it all set-up to be high-passed?

[StevenSurprenant]

The reason subs are hard to integrate is mostly because of crossover slopes and volume. If you are designing a full range speaker with a large woofer for bass you have to adjust the crossover so that where it overlaps with the midrange driver it doesn't cause a peak in the speaker output at those frequences. This is what causes boom and muddy midrange.

Most subs I have heard have a gentle slope (6 db/octave) at the crossover point. What happens with subs of this type is that they allow a great deal of higher frequencies to come from the sub itself so that when you adjust the crossover near the ideal setting, you get a combined peak from both the woofer and midwoofer resulting in muddy midrange and boomy bass. In addition, it is very easy to localize the sub which is a bad thing. If you turn the sub volume down to lower this peak at the crossover point, you loose your lower bass, but the midrange sounds better. If you set your crossover at a lower setting, your midrange gets better and you get the bass that you paid for, but now there is a hole in the sound between where the mid drivers leave off and the where the sub begins. In addition, you begin to find it harder to localize the sub in the room.

In an ideal world we would use a crossover on the mid driver to adjust it's output both at high frequencies and the lower frequencies. Then we would build a crossover for the woofer that has a slope that when added to the the slope of the midrange driver on the low end that would produce a flat output through the crossover region.

A better sub, IMO, is one that has a higher slope at its higher frequencies. These are easier to integrate with speakers because the overlap between the woofer and midwoofer is less.

By the way, I have also found that subs with a gentle slope integrate better with small speakers with very limited bass. (Less over lap)

If you cannot afford a better sub, the solution is to buy an equalizer or electronic crossover just for the sub. For instance, the Behringer DCX 2496 will allow you to set your slope to 48db/octave and it has built in EQ's including parametric EQ's. If you wanted to, you could also use it to set your slopes on your main speakers too. Actually, it does a great many things. Then there is the Behringer DEQ2496 which is a great equalizer for the money. You cannot adjust slopes but it does give you a great deal of control of frequency output. There are other brands, but Behringer is great for the money.

As for people thinking that subs don't integrate well, it's because most people don't know how to adjust them. It's a balance between slope, volume, and crossover point. Since most subs don't allow you to adjust slope then it will be more difficult. When a sub is adjusted correctly, you will not be aware that is is even on. What you will hear, for instance, is that drums will be more dynamic and as a side effect, your soundstage becomes more expansive. If you can hear (detect) your sub at all, means that you need to adjust it.

The bottom line in adjusting a sub is to think like a speaker designer. To integrate a woofer in a full range speaker, you need to select a crossover point, volume, and slope that allows it to merge together with the mid driver so that they sound like a single driver.

Well that should be as clear as mud.

Hope it helps...

One more thing...

One big advantage of subs is that bass interacts with a room more so than higher frequencies and subs can be moved and adjusted to correct these interactions. For instance, if you have standing waves at your listening position, you can move the sub to minimize the effect.

[Ajani]

The reason subs are hard to integrate is mostly because of crossover slopes and volume. If you are designing a full range speaker with a large woofer for bass you have to adjust the crossover so that where it overlaps with the midrange driver it doesn't cause a peak in the speaker output at those frequences. This is what causes boom and muddy midrange.

Most subs I have heard have a gentle slope (6 db/octave) at the crossover point. What happens with subs of this type is that they allow a great deal of higher frequencies to come from the sub itself so that when you adjust the crossover near the ideal setting, you get a combined peak from both the woofer and midwoofer resulting in muddy midrange and boomy bass. In addition, it is very easy to localize the sub which is a bad thing. If you turn the sub volume down to lower this peak at the crossover point, you loose your lower bass, but the midrange sounds better. If you set your crossover at a lower setting, your midrange gets better and you get the bass that you paid for, but now there is a hole in the sound between where the mid drivers leave off and the where the sub begins. In addition, you begin to find it harder to localize the sub in the room.

In an ideal world we would use a crossover on the mid driver to adjust it's output both at high frequencies and the lower frequencies. Then we would build a crossover for the woofer that has a slope that when added to the the slope of the midrange driver on the low end that would produce a flat output through the crossover region.

A better sub, IMO, is one that has a higher slope at its higher frequencies. These are easier to integrate with speakers because the overlap between the woofer and midwoofer is less.

By the way, I have also found that subs with a gentle slope integrate better with small speakers with very limited bass. (Less over lap)

If you cannot afford a better sub, the solution is to buy an equalizer or electronic crossover just for the sub. For instance, the Behringer DCX 2496 will allow you to set your slope to 48db/octave and it has built in EQ's including parametric EQ's. If you wanted to, you could also use it to set your slopes on your main speakers too. Actually, it does a great many things. Then there is the Behringer DEQ2496 which is a great equalizer for the money. You cannot adjust slopes but it does give you a great deal of control of frequency output. There are other brands, but Behringer is great for the money.

As for people thinking that subs don't integrate well, it's because most people don't know how to adjust them. It's a balance between slope, volume, and crossover point. Since most subs don't allow you to adjust slope then it will be more difficult. When a sub is adjusted correctly, you will not be aware that is is even on. What you will hear, for instance, is that drums will be more dynamic and as a side effect, your soundstage becomes more expansive. If you can hear (detect) your sub at all, means that you need to adjust it.

The bottom line in adjusting a sub is to think like a speaker designer. To integrate a woofer in a full range speaker, you need to select a crossover point, volume, and slope that allows it to merge together with the mid driver so that they sound like a single driver.

Well that should be as clear as mud.

Hope it helps...

One more thing...

One big advantage of subs is that bass interacts with a room more so than higher frequencies and subs can be moved and adjusted to correct these interactions. For instance, if you have standing waves at your listening position, you can move the sub to minimize the effect.

Thanks for that very detailed explanation. I suspect (though I don't know crap, so I might be wrong) that the peak in certain mid-range frequencies from a poorly integrated sub is the same peak that I hear reviewers talk about with some 2 1/2 way designs (especially the ones that use triple of the same drivers - for example 3 6.5 inch woofers - 1 as mid/bass and the other 2 as just bass).... while 3 ways (with dedicated mid range drivers) don't have that problem...

[Kevio]

If I may ask, how is it all set-up to be high-passed?

My Sony AV receiver does it for me.

[Kevio]

Well that should be as clear as mud.

Crossover design is a fairly complex topic. You've scratched at some of the variables and tradeoffs involved.

[StevenSurprenant]

Thanks for that very detailed explanation. I suspect (though I don't know crap, so I might be wrong) that the peak in certain mid-range frequencies from a poorly integrated sub is the same peak that I hear reviewers talk about with some 2 1/2 way designs (especially the ones that use triple of the same drivers - for example 3 6.5 inch woofers - 1 as mid/bass and the other 2 as just bass).... while 3 ways (with dedicated mid range drivers) don't have that problem...

You could very well be right about that.

Speaker design is an art mixed in with a little science. It's incredible how many ways there are to make speakers, What's more incredible is that many of the higher end speakers are made from parts that can be had on the open market for a very small percentage of the cost of the finished speakers. Think hundreds of dollars for the parts and thousands for the finished product. This isn't totally out of line because the amount of research and testing that goes into each model. To that, add in advertising, shipping, and dealer profit and the price begins to climb.

The two most important parts of a speaker is the crossover and the box. If either one is off just a little it can destroy any hope of having a soundstage or coherence. It's easy to run a computer program to tell you how to build the box and crossover, but then the hard part begins, testing and adjusting by ear. Sometimes it takes years to get it right.

It seems that many speaker manufacturers just whip speakers together to fit into everyone's price range. They just add more drivers or bigger drivers and increase the price. From the way their speakers sound, they spend very little time listening to them. Still, they sell them and people seem to be happy, go figure.

I realize that it seems like I got way off topic, but just wait.

There is a fairly new device available. It's called a DEQX and it's a type of auto calibrating crossover.

What it does is set crossover points for each driver and then adjust the frequency response across the entire spectrum for the entire speaker, but it doesn't stop there. Speakers have phase differences depending on the frequency and it adjusts those phase differences so that there is 0 phase variances. Then after that, It adjusts the speakers for the room effects. After all that is done, it is said that it can make an average speaker sound like a high end speaker. You can do a little research if you're interested. One of our members at audioreview has one of these.

The moral of the story is that crossover points and types, equalization of the frequency spectrum, phase variances, and room effects determine the final sound of a speaker system. Wha this tells me is that it's not so much the speakers that are used that determine the sound, but rather the crossover.

A speaker maker can control the crossover point and type, equalization of the frequency spectrum and to a degree, phase variances. This is why creating great speakers is so expensive. It is also the reason why great speakers sound so much better than speakers with mediocre crossovers. Under normal conditions, it is up to the owner to control room effects with sound absorbtion and diffusion.

You can read about it here: http://www.deqx.com/news.php

Sorry, got carried away with this, but I thought that you might be interested in knowing about this and how adjusting speaker parameters can effect the speaker sound.

It's very expensive, but it's kind of a cool thing.