LCR in exchange for Tower

[mike c]

let's say I like the sound of a certain speaker series ... e.g. Monitor Audio GS series.

I want the benefit of the towers but don't have the space for them ...

enter the LCR, I read the manual of the GS-LCR, it says that when using the LCR as left and right speakers, to orient them in a certain way so that the bottom woofer produces the "low bass" and the upper woofer produces the "mid bass"

if that is so, is the GS-LCR 2 1/2 way or 3 way?
looking at the manual, there is no mention of a second crossover setting - only the tweeter to crossover of 2.7khz.

so, without a second crossover, how does the lower woofer produce the low bass and the higher woofer produce the mid bass? gravity?

what do you guys think of a bookshelf vs. LCR speaker? am I correct to assume that the LCR should at least be better than the bookshelf speaker from the same series?

 

[MDS]

If there is one xover it is a 2 way speaker, although if there is one woofer and one'mid-bass' driver that is a passive radiator, I think that qualifies it as 2.5 way. 2 vs 2.5 vs 3 is irrelevant - they are artifacts of the implementation and you cannot conclude by that alone that one is better than the other.

LCR is a marketing term meant to signify that you can use 3 of them as the front array of speakers; it does not imply anything in particular about their suitability for that purpose. I could refer to my two front towers and dedicated center as LCR and it wouldn't change a thing.

Bookshelves are fine but usually need a decent sub to fill in the bottom end. I've never owned anything but 'tower' (if you can call 33" tall a tower) speakers and in general they go lower into the bass region than bookshelves and thus are a tad better IMO. But, as long as everything is matched reasonably well I think bookshelves are just fine with a good sub.

Edit: Come to think of it, my first Sony+JBL system right out of college was bookshelves placed inside a wall unit and they weren't bad at all.

 

[mike c]

you are correct of course that LCR is but a name ...

but a speaker which has TWO of the same drivers vs. a speaker with only ONE of the same driver should in fact be better, right? 2 way or 3 way aside ... (because the two drivers will divide the work and wouldn't have to do as much excursion as one driver to produce the same freqs.)

I'm thinking, if it is indeed a 2.5 way or 3 way, that would be more of a benefit, right?

I will be using a sub whether I pick the bookshelf or the LCR ...

 

[mike c]

doesn't anybody have any info on the MA GS crossovers?

 

[3db]

Hmmmmm, something doesn't sound right to me.

If the speakers were a 2 way design, and one had two of of the same drivers, then the driver exucrsion would be the same at a given input signal as a single driver. I think what you are saying is that you may not have to have the same level of input with the 2 driver the same configuration as opposed to a single driver configuration. If thats what you are saying, I don't if the sensitivity of a driver is linear or not thus reducing the excursion by half. In a 2.5 design such as my PSBT45, the lower woofer handles the lower half the bass only while the top woofer handles the remaining bass and midrange. I guess the top woofer's excursion would be lowered as the bass is not as prominent if that makes sense

you are correct of course that LCR is but a name ...

but a speaker which has TWO of the same drivers vs. a speaker with only ONE of the same driver should in fact be better, right? 2 way or 3 way aside ... (because the two drivers will divide the work and wouldn't have to do as much excursion as one driver to produce the same freqs.)

I'm thinking, if it is indeed a 2.5 way or 3 way, that would be more of a benefit, right?

I will be using a sub whether I pick the bookshelf or the LCR ...

 

[mike c]

If the speakers were a 2 way design, and one had two of of the same drivers, then the driver exucrsion would be the same at a given input signal as a single driver. I think what you are saying is that you may not have to have the same level of input with the 2 driver the same configuration as opposed to a single driver configuration. If thats what you are saying, I don't if the sensitivity of a driver is linear or not thus reducing the excursion by half. In a 2.5 design such as my PSBT45, the lower woofer handles the lower half the bass only while the top woofer handles the remaining bass and midrange. I guess the top woofer's excursion would be lowered as the bass is not as prominent if that makes sense

i think that's what I mean, BUT ...

I've heard 2 and 1/2 way speakers work like so:
one woofer produces BOTH mid and bass ... the other woofer produces only the bass below some frequency. so the mid/bass driver is still doing lots of work (if not all).

like you said, assuming the dual woofer speaker is a 2 way design, whether the sensitivity is linear or not linear, they would still 'share the load' right? (even if they're not equal)

from my first post, Monitor Audio mentions ' the bottom woofer produces the "low bass" and the upper woofer produces the "mid bass" ' ... that would lead me to believe it was a 3 way, right?

I asked the local salesman re: the above quoted sentence, he said that the signal both woofers received was the same (2 way), BUT since one was at the bottom and the other is at the top, they "sound" like they were producing different signals. I flat out laughed without showing hesitation, but now I got you guys ... tell me he's wrong. is he wrong?

I also emailed MA with some of these questions, but I would like some discussion here as well.

 

[3db]

Right or wrong, this is what I'm thinking

i think that's what I mean, BUT ...

I've heard 2 and 1/2 way speakers work like so:
one woofer produces BOTH mid and bass ... the other woofer produces only the bass below some frequency. so the mid/bass driver is still doing lots of work (if not all).

Thats what I meant

like you said, assuming the dual woofer speaker is a 2 way design, whether the sensitivity is linear or not linear, they would still 'share the load' right? (even if they're not equal)

I'm assuming that in a 2 way, the woofers are wired in paralel so that each woofer gets the exact same signal strength and therefore have the same excursion.

from my first post, Monitor Audio mentions ' the bottom woofer produces the "low bass" and the upper woofer produces the "mid bass" ' ... that would lead me to believe it was a 3 way, right?

I don't know how much overlap in frequency is needed to define something as a 3way or 2.5way design. If the midbass is truly midrange, then I would assume its a 3 way design

I asked the local salesman re: the above quoted sentence, he said that the signal both woofers received was the same (2 way), BUT since one was at the bottom and the other is at the top, they "sound" like they were producing different signals. I flat out laughed without showing hesitation, but now I got you guys ... tell me he's wrong. is he wrong?


I also emailed MA with some of these questions, but I would like some discussion here as well.

sounds like a 2 way design if they are receiving the same signal regardless of where the woofers are located within an enclosure.

 

[Joe Schmoe]

All this discussion of design subtleties makes sense if you are a DIYer, and trying to decide what to build. If you are just buying speakers, however, all that matters is how they sound to you.

 

[Swerd]

mike

I'm a little confused. The Monitor Audio brochure, from their USA web site, says that the GS-LCR is a 2-way (crossover at 2.7 kHz) and the GS20 tower is a 2.5-way (crossovers at 250 Hz and 2.7 kHz).

Are these same models available to you, or are they different?

 

[mike c]

All this discussion of design subtleties makes sense if you are a DIYer, and trying to decide what to build. If you are just buying speakers, however, all that matters is how they sound to you.

the ordinary bookshelf GS10 is fine with me, I just feel that it's too "small" and i'm thinking through theory that something with two drivers of which I like the sound would be better ... I can't demo dual GS-LCR's because there's none open, and there's only one in stock (unopened) I will have to order sight unseen if I wanted a set. so thus this discussion before rushing in to order

 

[mike c]

mike

I'm a little confused. The Monitor Audio brochure, from their USA web site, says that the GS-LCR is a 2-way (crossover at 2.7 kHz) and the GS20 tower is a 2.5-way (crossovers at 250 Hz and 2.7 kHz).

Are these same models available to you, or are they different?

they are the same... what is puzzling me is

http://www.monitoraudiousa.com/cms/uploads/userfiles/File/manual/Current Manuals/Gold Sig Manuals/GS Product Manuals/Gold Sig Manual CC,FX Rev2.pdf

the gs-lcr manual PAGE 5, second paragraph mentions what I said in the first post re: "low frequencies" going to the bottom driver, and "mid frequencies" going to the top driver. now without a crossover, how does that happen? gravity?

 

[mike c]

save you guys the trouble of downloading that manual

let me just post a pic from the manual ... last sentence

 

[mike c]

gs specs from the brochure ...

 

[Swerd]

The GS brochure suggests the LCR is a 2-way MTM speaker where both midwoofers are getting the same signal. The GS-LCR manual says the two woofers are not getting the same signal, but it doesn't come right out and say it is a 2.5-way speaker like the GS20 tower. Ask Monitor Audio to explain that better.

Another thing you might consider is that the GS10 bookshelf is in a ported bass reflex cabinet and the GS-LCR is in a small sealed cabinet. The bass from the GS10 might do as well or even better than the sealed LCR.

 

[mike c]

still no reply from MA ...

but I did ask them the tuning point of the port on the GS10, so maybe we can guess if the sealed dual driver LCR is a match for the ported GS-LCR.

 

[mike c]

1) at what frequency is the port tuning of the GS10? = 50Hz

2) at what frequency is the port tuning of the GS20? = 45Hz

3) what is the crossover frequency of the mid to bass in the GS-LCR if
there is one? (note: I am not talking about the tweeter to mid
crossover) approximately 500Hz

4) is the GS-LCR 2 way or 2.5 way? if it is 2-way, do the two woofers
get the same signal? if it's two and a half way, does the other woofer
get mid/bass and the other bass?

The GS-LCR is a 2.5 way the Bass Driver crossing over at approximately
500Hz

now my follow up questions:
1) with a port tuning of 50hz, does that mean that above 50hz the driver is doing the work?
2) if it is, does that mean if I crossover at 80hz, the port will be less of a factor in the sound? (I know the port makes the woofer efficient, in the sense that there's no back pressure, right?)

 

[Swerd]

1) at what frequency is the port tuning of the GS10? = 50Hz

2) at what frequency is the port tuning of the GS20? = 45Hz

3) what is the crossover frequency of the mid to bass in the GS-LCR if
there is one? (note: I am not talking about the tweeter to mid
crossover) approximately 500Hz

4) is the GS-LCR 2 way or 2.5 way? if it is 2-way, do the two woofers
get the same signal? if it's two and a half way, does the other woofer
get mid/bass and the other bass?

The GS-LCR is a 2.5 way the Bass Driver crossing over at approximately
500Hz

now my follow up questions:
1) with a port tuning of 50hz, does that mean that above 50hz the driver is doing the work?
2) if it is, does that mean if I crossover at 80hz, the port will be less of a factor in the sound? (I know the port makes the woofer efficient, in the sense that there's no back pressure, right?)

Well OK then, GS-LCR really is a 2.5-way speaker. Monitor Audio should correct its brochure.

To answer, your follow up questions:

1) The driver in a ported cabinet always does the work . Around the port tuning frequency, 50 Hz ± about 10-15 Hz in the example of the GS10, the port tube's resonance reinforces the weaker response of the woofer.

2) If you use a subwoofer, with a crossover at 80 Hz, a port tuned to 50 Hz will not contribute much if at all to the sound.

If you do intend to use a subwoofer this way, I'm not sure that a 2.5-way speaker like the GS-LCR will be better than a 2-way in the mid to lower bass response. An MTM design will still present the upper midrange differently than a 2-way. The vertical dispersion (if the MTM is standing vertically) will be broader and somewhat more uniform than a 2-way, especially within one octave of the woofer-tweeter crossover frequency of 2.7 kHz.

Good luck with your choice.