Good bookshelf speakers should not be any less than comparable tower speakers

[TLS Guy]

Ok, take for instance my Elac Debut 2.0 B6.2 which are a 2 way speaker with a 6-1/2" woofer and 1" tweeter crossed over at 2.2Khz.

The Flagship tower speaker of the Debut 2.0 series is the Debut 2.0 F6.2 which is a 6-1/2" driver and a 1" tweeter crossed over at 2.2Khz, then an additional two 6-1/2" woofers crossed over at 90hz. This is essentially the B6.2 bookshelf speaker with a dual 6-1/2" driver subwoofer added. LIke I said, I cross over to my subwoofer at 80Hz from my B6.2 bookshelf speakers.

Now it seems the argument is upper bass response where I have always read where soundstage and presentation was the big difference but didn't agree with.

With many other tower speakers, they use up to three 6.5" woofers where the bottom two woofers use a 2.5 way crossover that rolls them off at the lower frequencies as well.

Looking at a spinorama chart, there is no benefit in the higher bass in a tower speaker opposed to a bookshelf speaker that shows flat upper bass as well.

You are just comparing it to another dumb design, which is most speakers these days.

 

[TLS Guy]

You're adding bunkum, tho. Many fundamentals are below what you mention, or you have a strange definition of fundamental? Many speakers, even floor standers, do fall short but depends on spl levels, room size, etc.

The OP's claim that a random pair of bookshelves with a sub are superior to a good pair of floorstanders, meh. Depends on particulars of speakers, subs, room size, listening levels, etc.

The fundamental of an instrument is the lowest frequency it will reproduce. Then that fundamental will have harmonics which will either be second or third order, depending on the instrument. If it is an open string or a pipe type instrument open at both ends it will have even order harmonics, if it is a pipe closed at one end it will be odd order harmonics. The intensity of the harmonics decrease in proportion to their order. So a second harmonic is less intense than the fundamental and the fourth lower intensity still and so on. For instruments that have odd order, the fifth harmonic will be lower intensity than the fundamental than the third and so on.

So, you can see that the power of a speaker really needs to concentrate its resources round the cluster of the harmonics of most instruments. This is very basic physics that I have known since I was a child. I would not have past my GCE physics exams at school if I did not know that, and a lot more about the natural order.

I have to say, I often wonder how deficient speakers designers are in their knowledge of acoustic physics. I think a lot know an awful lot less than they should.

 

[Mike Up]

Have a closer look at the compression and multitone measurements, at freq above sub range. The bookshelves compress and go nonlinear at much lower spls than the towers. Distortion is only 20db down at higher spls, while the towers are kept below -30db at the same high spls.

I'm not saying the results from sub/sat vs. towers are not ok for the right implementation, just that they are dynamic range limited, in the power band below 500hz or so. Trying to fill a large room involving greater distances will have one pushing directly against the limits of the sub/sat combo. Not "equal or better" objectively, but perhaps sufficient for smaller settings or nearfield use and yeah, less expensive than the towers.

Ok did you bother to read to the left of the graph and look at the scale? The difference from 500Hz down to 80Hz between those 2 speakers (which BTW do have different drivers) is only about .5db! Yeh, not much if anything.

Looking at another different tower speaker with different multiple 6-1/2" woofers again, and costing over $6000 is the Dali Rubikore 6. It's frequency change at 102dbs isn't much different than the $480 Elac Debut 2.0 B6.2 Bookshelf speaker.

The only thing that has been proven is that using a subwoofer is beneficial over the poor low bass output of most tower speakers and crossing over at 80Hz or above corrects any significant bass output changes at 102db, at least in my bookshelf speakers.

By the way, in my listening area, listening at 102db out of each speaker for prolonged periods will likely cause hearing damage. I found listening at 89 db to be as as loud as I would want, if not too loud to be even comfortable listening in my room. My speakers sensitivity are 87 db with 2.83V at 1meter.

 

[lovinthehd]

The fundamental of an instrument is the lowest frequency it will reproduce. Then that fundamental will have harmonics which will either be second or third order, depending on the instrument. If it is an open string or a pipe type instrument open at both ends it will have even order harmonics, if it is a pipe closed at one end it will be odd order harmonics. The intensity of the harmonics decrease in proportion to their order. So a second harmonic is less intense than the fundamental and the fourth lower intensity still and so on. For instruments that have odd order, the fifth harmonic will be lower intensity than the fundamental than the third and so on.

So, you can see that the power of a speaker really needs to concentrate its resources round the cluster of the harmonics of most instruments. This is very basic physics that I have known since I was a child. I would not have past my GCE physics exams at school if I did not know that, and a lot more about the natural order.

I have to say, I often wonder how deficient speakers designers are in their knowledge of acoustic physics. I think a lot know an awful lot less than they should.

So we're on the same page with fundamental definition at least. Many speakers aren't particularly capable of fundamentals let alone their harmonics.

 

[ski2xblack]

...I found listening at 89 db to be as as loud as I would want, if not too loud to be even comfortable listening...

Good, and sensible for your hearing's sake.

Bonus: the bookshelf speaker / sub combo is a cost effective and sufficient solution for your particular situation and listening habits.

Now get back to the music.

 

[AcuDefTechGuy]

Using an active subwoofer under 80Hz makes the low bass output of the tower-woofer a none-issue, Making a 2.1 bookshelf speaker/subwoofer an equal or better option, as said.

Well you have to take in total system design. Generally it is best to set the sub crossover at least 50% above the F3 of the main and center speakers. However, if the mains are really capable I think it is best to play the mains full range and supplement with the sub or subs. However, there seem to be fewer and fewer speakers available where that is a good idea.

I did find an exception to this, and that was my inwall system. I moved the crossover up to 150 Hz as the multiple wall reflections were causing havoc, and just have the 10" sub driver reproduce below 150 Hz really cleaned up the total definition of the system.

In essence, I don't think there is a hard and fast rule on all this, as speakers have different capabilities and room situations are a huge wild card.

If the F3 of the mains/center is 30Hz, 50% of 30Hz is 15Hz. So at least 50% above the F3 would be at least 45Hz (30+15) ?

Back when I had the Revel Salon2 and Linkwitz Orion 3.2.1 towers which have F3 close to 20Hz, I think I was still setting the XO to 120Hz or 150hz.

 

[j_garcia]

I have always been a fan of large bookshelf speakers. Ever since the days of the Paradigm Studio 40, and probably since that era, I've always had large bookshelf speakers. I've owned towers as well. If I wanted to listen to music only, I might opt for good towers and no sub. The BMRs extend pretty low since they are about as big as you get in a bookshelf, so I get good response, but not enough for a room this size. I am about 50/50 music vs. movies though, so there is always going to be a sub.

 

[AcuDefTechGuy]

I think there's only 2 types of speakers - bigger dynamic speakers and smaller less-dynamic speakers.

And the biggest difference between them is the sound DYNAMICS. The bass portion doesn't have to be a big deal because you can always add subwoofers to any system.

So the main question is, do you want more dynamics or not?

If you don't want more dynamics, then smaller speakers and subs are perfectly fine.

I want BIG BASS and I'm not gonna lie.

 

[ski2xblack]

If the F3 of the mains/center is 30Hz, 50% of 30Hz is 15Hz. So at least 50% above the F3 would be at least 45Hz (30+15) ?

It depends, there is wiggle room with possible settings, and speaking of room, the room itself is inflicting it's own acoustic molestation on those low frequencies.

For reflex loaded mains the general rule of thumb is to high pass an octave above the speakers acoustic roll-off, so for your example and assuming a reflex alignment, the hpf should be 60hz as a starting point. (The rationale is to sidestep the phase shift inherent to reflex loading, making the crossover to subs easier to accomplish, whether that's you calibrating manually or relying on automagic room correction/sub calibration.)

Higher hpf settings can be used to address the idiosyncrasies of particular setups, e.g. TLS' in-wall family room system. You do it too in at least one of your rigs, don't you? As long as the sub has extended enough high end response to do it and are somewhat co-located with the mains to avoid localization issues, no problem with a higher hpf setting.

Sealed mains are a slightly different beast. I have a rig with sealed mains that somewhat adhere to the old THX standards, rolling off at the expected 12db/oct, and the hpf ended up directly coinciding with the speaker's roll off. Based on the ol' polarity reversal test, it results in an almost ideal LR4 alignment and works very very well.

So, yeah, some wiggle room exists, and each room demands empirical evaluation and adjustment to arrive at what works best.

 

[AcuDefTechGuy]

It depends, there is wiggle room with possible settings, and speaking of room, the room itself is inflicting it's own acoustic molestation on those low frequencies.

For reflex loaded mains the general rule of thumb is to high pass an octave above the speakers acoustic roll-off, so for your example and assuming a reflex alignment, the hpf should be 60hz as a starting point. (The rationale is to sidestep the phase shift inherent to reflex loading, making the crossover to subs easier to accomplish, whether that's you calibrating manually or relying on automagic room correction/sub calibration.)

Higher hpf settings can be used to address the idiosyncrasies of particular setups, e.g. TLS' in-wall family room system. You do it too in at least one of your rigs, don't you? As long as the sub has extended enough high end response to do it and are somewhat co-located with the mains to avoid localization issues, no problem with a higher hpf setting.

Sealed mains are a slightly different beast. I have a rig with sealed mains that somewhat adhere to the old THX standards, rolling off at the expected 12db/oct, and the hpf ended up directly coinciding with the speaker's roll off. Based on the ol' polarity reversal test, it results in an almost ideal LR4 alignment and works very very well.

So, yeah, some wiggle room exists, and each room demands empirical evaluation and adjustment to arrive at what works best.

What about just doing REW measurements (measure combined speaker + sub) to see which XO gives you the best FR for your system?

Or doing REW measurement to see which system gives you the best FR - small speaker + sub vs large speaker + sub vs large speaker w/o sub ?