I have a cheapo Tannoy SFX 5.1 speaker system from a few years ago. It apparently was available with a dedicated centre speaker, with two mid drivers in it, or just 5 satellites. I have the latter.

Question is, why do centre speakers often have two drivers like that? Is it just to increase sensitivity ie more volume for the centre channel? If so, why is this different from just turning up the centre channel in the amp setup?

I often have difficulty hearing the dialog in movies. I thought maybe this was because the dynamic range of the audio track was so great, perhaps because people like really loud explosions and stuff when everything else is at normal levels. I’m often listening when the kids are in bed so I’d rather have sensible explosions and be able to hear the speech.

Would a centre speaker with two drivers help? Is it possible to just wire up a second satellite in parallel to the centre to achieve a similar effect?

I wouldn’t.
I don’t think it makes any difference at all.

I think it’s done in order to keep speakers slim and visually symmetrical. They therefore choose to run 2 small drivers instead of one big one.

Does your amp have the option to run at a compressed level – sometimes called Dynamic Range Control or ‘night mode’ or some such. That can help.

Does your amplifier have gain settings (normally in dB) for each channel?
If so you can boost the volume of the centre speaker that way.

My amp came with a microphone that you place where you normally sit. It then runs a series of sounds through each speaker in turn. At the end if has a different gain setting for all the speakers.

Speaker position is important as well. If you can point the centre speaker slightly upwards so it is aiming more at your ears rather than knees. Front of mine rests on two halves of squash ball.

I think it’s done in order to keep speakers slim and visually symmetrical.

nail on head!

I’ve been using a Sony SA-VE815ED Pascal system, like this one:

The satellite speakers, as you can see, have twin midrange drivers, with a tweeter in the center, the idea being, as Alex says, to keep the enclosure as slim as possible, with a similar volume to a box with a single driver. Mine sound fine, I have absolutely no problem picking out dialogue, and they reproduce music very well, too. Mine must be at least fifteen years old, I’ve seen reviews of the 835 system dated 2001.
Got mine with the Yamaha amp I still use for half price, as the shop was refitting; £500 instead of £1000. They still get good prices on fleabay.

60% + of the audio on a 5,1 soundtrack comes from th centre so it is the most important. Doubt it will make a noticeable difference though – seek out night mode

There is a gain control for the centre, it is already up. In this case it’s not a case of using two smaller drivers, the dedicated centre has two of the same drivers the satellite has.

Will try angling it upwards.

my center has front porting so you can use it in a cabinet or fix to wall for better setup and also the bass frequency response is better than the satellites for better dialogue reproduction.

On the Pascal system, there’s no difference between the speakers, they’re all interchangeable, the only difference is the stand that bolts onto the speaker.
Can you drop the volume for the front L/R satellites in your amp’s settings menu? My sub has it’s own switch for music/cinema on the top, and there’s settings for L/M/S speakers in the amps settings, for F/R, L/R, and C.
It might be worth thinking about a change, getting a more up-to-date amp, with a wider range of speaker settings, and some better, smaller satellites, maybe a Yamaha or an Onkyo, with KEF satellites.

It might be worth thinking about a change

Oh yeah I’ll just drop a couple of Gs that should fix it 😉

Will try angling it upwards.

That made a big difference to my system. Speaker sits on a shelf under the TV so a bit low. Front now propped on two half squash balls.

I don’t have a home cinema set up, but I do find that too many action/adventure/Sci-Fi films are engineered in a totally inappropriate way for “kids in bed” listening. The action is too loud and the dialogue and quiet scenes are way too quiet. Change your film habits 😉