Full Range for Surround Center Channel?

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Qts is too high for a MLTL.
And it should barely reach 10,000Hz, according to specs.

Qts actually measures lower than published. Using the Dayton WT-3 I measured Qts=0.69, which I find on the high side of ideal, but still well usable. I've discovered that the smallest volume of an MLTL speaker (all else being equal) is for Qts=1/(SQRT(2))=0.71. I like small MLTLs.

Secondly, if they "barely reached 10kHz" they'd be painful to listen to. They're not.

That would be a perfect driver for a portable party boombox, but for a centre channel, I wouldn't be too sure.

Here I agree, they would be excellent for a party boombox. For center channel, I'd try them. They would fit the prescribed footprint.
 
Re PBLX:- I too am begining to find the concept of ultra low mass enclosures very very interesting.

As Qts' increases, cab compliance can increase to compensate, so in T/S theory the corner Qb = 0.707.

Unfortunately there's no chart AFAIK to give us any idea what materials+ assembly details to use with rising Qts', so about all one can do is use an impulse response as a guide.

Qts' = Qts + any added series resistance [Rs]: HiFi Loudspeaker Design

GM
 
Qts actually measures lower than published. Using the Dayton WT-3 I measured Qts=0.69, which I find on the high side of ideal, but still well usable. I've discovered that the smallest volume of an MLTL speaker (all else being equal) is for Qts=1/(SQRT(2))=0.71. I like small MLTLs.

Secondly, if they "barely reached 10kHz" they'd be painful to listen to. They're not.



Here I agree, they would be excellent for a party boombox. For center channel, I'd try them. They would fit the prescribed footprint.

I based my ramblings while looking at the specs shown on the website. If they measure differently, then I have no way of knowing what they really are! :)

Got some measurements for them?
 
Sorry if I'm dense, but can you clarify? "On axis" meaning the centers of the drivers are on the same vertical axis? or horizontal axis? or other?
"A bit of extra EQ on the top" means more power to the driver that's physically on top? or on the higher frequencies? or other?

Thanks,
Eric

Eric,

a picture might be easier here (sorry for the crude pictogram). On the left, the driver mounted under the TV will usually fire too low, and the on-axis is around your waist. That means that your ears are off-axis and the higher frequencies will drop off because most full range drivers will beam at higher frequencies and lose intensity when you move off-axis.

On the right, if you angle the baffle, it will give you more area to mount the driver, and it will be closer to on-axis to your ears.

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If this graph of the A10P is anywhere close to reality, then you'd want to have your ears between 5 and 15 degrees off axis. It also will depend on your sitting position's distance from the driver and your listening preferences.

An externally hosted image should be here but it was not working when we last tested it.
 

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frugal-phile™
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Okay, I understand that the A10 may be the best choice. But humor me and assume that it's just too big for my situation. \

Then you want a driver with the same voice. For A10.3 that would be A7.3/A6.2m/A5.2. For A10p you are liited to A6.2p. 5-9 litres for the A7, as small as 2litre for the A5.2.

I don’t think i have done them all, but i should have a miniOnken centre as FH companions for all of these.

dave
 
Then you want a driver with the same voice. For A10.3 that would be A7.3/A6.2m/A5.2.

So I'm leaning toward the A7.3 (or possibly the A6.2M) to pair with my A10.3 main speakers, in a vented alignment (BR or MLTL), and angling the baffle upward slightly as perceval suggests.

I don't think the over/under arrangement is going to pass the WAF test.

Given that, is a single driver the best choice, or two drivers? If my only option for two drivers is to mount them beside each other, does two drivers offer any advantage or just create it's own set of problems?

Thanks,
Eric
 
I’ve used singles of both A7.3 and A10.3 as centre channel (Lo passed as high as 100), and would definitely recommend the larger of the two if you can accommodate the enclosure size. Mine is a variation on one of the centre enclosures to which Dave posted a link to previously, with the front panel slanted up at 5dg.
 
Given that, is a single driver the best choice, or two drivers?

Again, should all be identical across the front, but if must go smaller, then what can come closest in PRaT or at least in the critical 250-3500 Hz phone BW ['voice'] and in smaller HTs the CC may need a super tweeter to get enough off axis coverage on a three wide row, but I gather you won't have the baffle height for one if you need it, so academic.

In short, only a focussed over n' under is suitable for dual 'anything' for high speech intelligibility.

GM
 
Okay, no progress yet on my center channel, but I got around to attaching all the wires on my new avr (Onkyo TX-RZ630) and ran the initial setup using the supplied calibration mic. My system is only 2.1 so far, as I'm using channels 6/7/8/9 for remote zones.
Anyway, was a bit surprised that after running the AccuEQ setup, it selected a crossover frequency of 40 Hz for my front speakers, and an LFP of LFE of 120 Hz. That seems like a lot of overlap doesn't it? My front speakers are MLTLs that with an F3 of about 43 Hz, so can reach down that far, but I expected that the two "crossovers" selected by AccuEQ would have less overlap. Is this expected? Is it reasonable/good?
Thanks,
Eric
 
Eric, sounds like you’re early on your journey down the rabbit hole of multi-channel. Some interesting features on that RZ series. In my own case, adding small PLIIz front height speakers (Pluvia7 in top corners) and research surrounds (A5.2) made a huge difference in the overall sensation of space and, well being surrounded by the on screen events - Kings Landing “battle” scene, for example.
Although it looks like Onkyo have departed from Audyssey and adopted their own calibration / EQ function, unless the interface and manual setup options buried a few layers deeper than the auto mode, you can still adjust those crossover frequencies on the fly to find settings that may work better for your ears than the defaults. I chose the setting of 80Hz labelled as THX standard for the front row, and 120Hz for the peripheral surrounds.

Have you tried the phono input? While I’ve not seriously listened to my ‘table in probably 5 years, I did test it out on the NR830, and it was surprisingly non-hurtful.

I continue to be amazed at the amount of functionality and relative ease of use the designers of modern surround receivers can cram into a single box. I think we all know guys who’ve spent more money on snake oil infused speaker and interconnects than your unit cost.
 
Eric, sounds like you’re early on your journey down the rabbit hole of multi-channel.

That's not the plan, but who knows.....presently planning to stop at 3.1!


Although it looks like Onkyo have departed from Audyssey and adopted their own calibration / EQ function, unless the interface and manual setup options buried a few layers deeper than the auto mode, you can still adjust those crossover frequencies on the fly to find settings that may work better for your ears than the defaults. I chose the setting of 80Hz labelled as THX standard for the front row, and 120Hz for the peripheral surrounds.

Yes, the "manual" adjustments are still easily accessed, but I wanted to see what the auto mode came up with on its own. Actually, one of my main motivations for replacing my old stereo receiver with this unit was to be able to use the crossover to limit the low frequency inputs to my two front speakers. I was expecting the auto mode would cut them off higher. I may try 80 Hz for the fronts like you have set and see how I like that. The ironic thing is that I designed my front speakers to reach down close to 40 Hz, and now I've bought a sub and crossover and plan to prevent them from trying to. It makes me feel a little dirty somehow...

Have you tried the phono input?

Haven't and probably won't. I haven't had a turntable since about 1985 and at Christmas gave all my albums to my daughter!

I continue to be amazed at the amount of functionality and relative ease of use the designers of modern surround receivers can cram into a single box.

Pretty cool indeed for cheapskates like me!
 
it selected a crossover frequency of 40 Hz for my front speakers, and an LFP of LFE of 120 Hz. That seems like a lot of overlap doesn't it?

These systems do time delay correction, so where there's a need it will 'gap' the XO same as is done with prosound horn/woofer or similar speakers to get 'close enough' delay added when they aren't physically aligned.

GM
 
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