How much bass is best for a center channel: 2-way or 3-way?

[JonW]

I’m just starting to think about designs for a center channel speaker. And wondering about how much bass extension is good to have in a center channel speaker for a movie setup. Is crossing to a sub the ideal? In which case you only need to play cleanly down to ~80 Hz. Or might it be best to run a center channel full range if it can reach deep enough?

Generally speaking, a 2-way MT design could be good for a center channel. A 2-way MTM might be even better in terms of output, lower distortion, power handling, etc. And a 3-way, say a WMTW, might be better still. But if the center is crossed to a sub, then much of the benefits of going 3-way (i.e., better bass extension) could be wasted. In which case a solid 2-way center design could be quite good. I guess there might be benefits of 3-ways over 2-ways even when using the same sized woofers, such as the mid taking some load off the woofers, etc.

I realize there are other center channel issues with regard to driver and speaker orientations influencing off-axis performance and such. But for here I’m wondering about the potential benefits of going 2-way versus 3-way mostly in terms of bass extension and clarity. Thanks.

[Fronn]

I prefer to cross things at 60hz, personally.

80hz is still hovering in the range where it's still possible to hear the source of the bass, so it's better to have that coming from where it should.

Unless you're center can go down to <20hz, I wouldn't run it full.

[---k---]

One issue to consider is if your receive can do different crossover points for your center than mains. Most receivers only have one crossover point for all the speakers. This may be slowly changing.

If you're talking about a center, then typically you're talking about movies which commonly have fun content between 15 hz and 30 hz. So, no matter what mains you have, you're going to want to cross them to a sub. For the big musical soundtracks, there is tons of bass content in the center. So, it isn't like they mix without bass in the center track. I think it is a good thing to have good bass extension down to 50 hz in all speakers, so you're really only needing the sub for the big booms. With my speakers, ideally, I would cross my mains at 50 hz and the center at 80hz. Its an issue with my current receiver (but not that sexy upcoming Outlaw).

Dolby THX, of course, says all speakers cross at 80hz.

I also think you're forgetting how much better a 3-way can sound than a similar 2-way due to the bass being taken off the little speakers. My Khans should just be the same as CJD's MTM, but with better bass extension, but I can tell you they are that and much more.

[cjd]

Ryan, you should be able to cross the center at 70Hz. That's where I'm crossing mine - if I push really loud I can still overextend but my ears don't like that, regardless.

IMO alignment is the thing to target. If you want more drivers, a WTMW 2.5 way with the TM vertical and the same driver for the W's and the M is still preferable IMO.

80Hz THX spec was picked as a fair compromise in what kind of speaker is easy to produce that's small and cheap for mains, and where the content would become too localisable to the sub. Well, partly. I ignore that spec and use a target based on the same reasoning as if I were building a 3-way or a 4-way. Distortion, excursion, everything else.

C

[JonW]

Thanks guys. I guess what I’m wondering is if there’s any major benefit to going 3-way in a center channel versus a 2-way. Sure, various factors come into play (distortion, off-axis nulls, etc.). But if you’re always going to use a sub, regardless of how deep the center speaker can reach, then bass extension is one less thing to worry about in the design choices.

Unless you're center can go down to <20hz, I wouldn't run it full.

For the big musical soundtracks, there is tons of bass content in the center. So, it isn't like they mix without bass in the center track.

Makes sense. However any decent 2-way can play to ~50 Hz.

I also think you're forgetting how much better a 3-way can sound than a similar 2-way due to the bass being taken off the little speakers.

No, I’m not forgetting. I just don’t have a fell for how much that’s really the case. :B It makes perfect sense- more drivers allow each to one to do its thing better and all. But in the real world is there a noticeable difference? You’re saying there is. Good to know.

IMO alignment is the thing to target. If you want more drivers, a WTMW 2.5 way with the TM vertical and the same driver for the W's and the M is still preferable IMO.

I ignore that spec and use a target based on the same reasoning as if I were building a 3-way or a 4-way. Distortion, excursion, everything else.

I’m trying to figure out if you really do want more drivers or not. A plus for more drivers is more bass, but that’s not much of a plus if you’ll always use a sub. And my current understanding is that for horizontally-oriented speakers, more drivers may actually make off-axis nulls worse. A small, horizontal MT is best in this regard. Not sure if that’s correct. But if it is, more drivers may not be an obvious benefit- could even be a bad thing. But then there’s also distortion where more drivers are better, of course. So an MTM 2-way could be a good middle ground. Or not. I’m still trying to understand these things. We are speaking in generalities so there’s probably no one answer...

[---k---]

Jon,
I understand where you're coming from. Not trying to say either way is the best, just trade-offs between absolute quality and price. I probably would said a simple 2-way was sufficient a year or so ago. During movies, who actually critically listens enough to hear the differences? But now, I think I would take my center any day over an MT or MTM with similar drivers because I've heard RS MTs and MTM's with a sub and prefer mine.

[JonW]

Thanks Ryan. That helps- hearing that you prefer the 3-way over 2-ways, even though my guess is that you are not picking up any extra bass extension. I wouldn't mind also hearing from others if they have similar experiences.

I could try and design a 3-way center partly because I could use an upgraded one. And also it could be a good way to cut my teeth on designing 3-ways, as practice for moving up to an eventual all-out 3-way design for music.

[cjd]

Yeah, 2.5 way probably is moot unless you're using really small drivers. This is where you'd just be outside the excursion limits without additional drivers.

3-way still results in less upper midrange distortion from excursion. Which is why a 2.5 way probably doesn't help so much. I probably should have said a 3-way with the same drivers for woofer and mid is still perhaps preferable to a TM. MTM horizontally does comb. If you cross the horizontally aligned drivers low enough there isn't the combing problem, though off-axis still isn't as good as a pure vertical alignment.

Best results are had with a pure vertical alignment of 3-ways behind an acoustically transparent screen...

C

[---k---]

.. double post

[---k---]

Best results are had with a pure vertical alignment of 3-ways behind an acoustically transparent screen...

C

Blahhhhh Have you solved that comb filtering problem yet? :P

(I agree with Chris actually)

[kgveteran]

I use three centers WTMW.They rolloff around 50hz.I cross them over at 100hz with my receiver. I've been trying to convince myself that they lack midbass, but I just played the Scorpinox scene from transformers at reference level and I think I'm barking up the wrong tree. I think I'll put that upgrade money towards Christmas gifts for the family and be thankful I built these speakers.

[Carl V]

many good & valid points posted.

But don't focus on the 80Hz spec.

what really makes a good 3-way shine
is in the power region of music or movies.
for sake of simple numbers think 80Hz-280 or 380Hz
It's a question of dynamics

For this reason I have prejudices against small mid-woofers
(all else being equal...& that rarely exists in life) in 2 ways. ymmv
and 100-150mm is small...imho

If however you're doing a nice 3 way WTMW as the previous
poster has, 3-LCR, he has two 180mm mid-woofers as his woofer.
The helps out on the upper bass & lower mid range. I've heard
the NeoCC desing of Jon's...again upper bass & lower mid range
were excellent. Selah Audio has Tanzintes...which are also quite
nice. 2 Midwoofs aren't about extension (lower Hz) as much
as it's about senstivity & spl output.

And as for 50--60--80--100 Hz knees....it's more about integration
& room set-up. I've done it many ways & done the A/B stuff. If
you've done some due diligence in your setup it won't matter
that much.

[kgveteran]

You have to imagine that the subwoofer is handing the signal over to the woofer or midwoofer.It better have the same intensity as the sub system or something is goin to be missing.It's not like handing over the midrange to tweeter signal. I think it's a displacement issue, and 6.5" midwoofers can't be asked to do midrange duty and bass.Too much is lost in the midrange trying to produce bass.

Threeways are a real improvement in this area.Especially the designs in the Accomplished section.


Kg

[JonW]

what really makes a good 3-way shine
is in the power region of music or movies.
for sake of simple numbers think 80Hz-280 or 380Hz
It's a question of dynamics

3-way still results in less upper midrange distortion from excursion. …((snip))… I probably should have said a 3-way with the same drivers for woofer and mid is still perhaps preferable to a TM.

Threeways are a real improvement in this area.Especially the designs in the Accomplished section.

OK, so the consensus seems to be that a good 3-way center is preferable over a good 2-way, even if the 3-way does not pick up any extra bass extension. That all makes perfect sense from a textbook standpoint. I didn’t know if it translated as such into the real world.

For example, take Jon’s NeoD CC 3-way with 6.5” woofers. Sounds like you guys say there should be a noticeable difference between those same HiVi 6.5” woofers in a 3-way WTMWW versus a WTW or a WT.

Best results are had with a pure vertical alignment of 3-ways behind an acoustically transparent screen...

Actually, my current setup is a vertically aligned MT behind a screen. But I may move the whole system into another room, in which case I won’t have the screen anymore. Also, there’s a level of performance above my current MT I’d like to hit (lower distortion, etc.). And I was wondering if the better drivers should be in an MTM or 3-way WTMW, etc. configuration. Maybe I’ll try and whip up a Scanspeak 3-way center channel…

I use three centers WTMW.They rolloff around 50hz.I cross them over at 100hz with my receiver. I've been trying to convince myself that they lack midbass, but I just played the Scorpinox scene from transformers at reference level and I think I'm barking up the wrong tree. I think I'll put that upgrade money towards Christmas gifts for the family and be thankful I built these speakers.

kg,

For whatever it may be worth… If there’s a little lack of clarity, lack of midbass, etc. you might want to consider moving up to a design with better drivers. Your WTMW is a very well designed speaker, so the design is not an issue. And you have tons of output, so also no issue there. I built the Modula MT’s, which use similar drivers to your WTMW’s. They are excellent speakers, to be sure. But not quite as clear and precise as what I was after. So I recently finished some MT speakers using lower distortion drivers (Scanspeaks) and, to my ears, there is a significant difference. The midrange clarity I was after is now there. Expensive speakers, though. And as we’re discussing in this thread, I may want to try a similar quality WTMW center speaker. An idea I’m chewing on at the moment. Just my experience to pass along. That said, your family will probably prefer that you stay happy with your current speakers.

[JonW]

I just had a "well duh!" moment...

If you think about a typical WTMW center channel like the one kgveteran shows above... well the TM part is oriented just like a regular MT speaker. So you get all the benefits of a vertically oriented speaker (down to the M-W crossover point). No compromise at all with regard to off-axis performance. Assuming you can deal well with the very wide baffle that the t and M see.

So WTMW is better than MTM for a center because you get better off-axis performance, more extended bass, and better all-around clarity from less effort from each driver. The cost and size drawbacks are still there.

OK, I'm slow.

[cjd]

mmmhmmmm, yup.

In my personal opinion, some of the crossover offerings posted with that WTMW weren't optimal. I also recall never quite being sure what tweeter was measured with...

[kgveteran]

mmmhmmmm, yup.

In my personal opinion, some of the crossover offerings posted with that WTMW weren't optimal. I also recall never quite being sure what tweeter was measured with...

Ok.....have we done anything about this. I didn't know there were any issues.

Sorry about the hijack ops:

[---k---]

and that is why the Khancenter is soooo much better.

(as long as you're going to put a big box tv over it.)

[kgveteran]

and that is why the Khancenter is soooo much better.

(as long as you're going to put a big box tv over it.)

Oh, poppy-cock ! Thats crazy ! Sooo much better.....

I would like to see a Jon Marsh XO for the WTMW. Probably about 225.00.That man doesn't skimp

[---k---]

Oh, poppy-cock ! Thats crazy ! Sooo much better.....

I would like to see a Jon Marsh XO for the WTMW. Probably about 225.00.That man doesn't skimp

Here you go: https://www.htguide.com/forum/showth...962#post221962

CJD also did a crossover. CJD is just being a perfectionist. Ignore him.

[kgveteran]

Here you go: https://www.htguide.com/forum/showth...962#post221962

CJD also did a crossover. CJD is just being a perfectionist. Ignore him.

And the scoo-matic ? I can't seem to find anything tonight.

[jquin]

Hi
I don't want to be rasing a red herring here but aren't subwoofers in any HT setup really there for special effects
ie jurassic footprint
You know the kind of stuff that rattles the ordaments off the mantle.
After having built a M8ta I don't think i would need more than that for music.

If you have a set of full frequency mains and possibly center then the sub should be crossed really low like 80Hz or something.
More a question than a statement I guess.


Anyone know how low in freq the Dolby & DTS soundtracks go?

[chasw98]

Jon:
Out of all the posts that have replied I have not seen 2 distinct points brought up.

The first point has to do with whether or not a center channel is really needed/wanted/neccesary. I have the same center channel as kg but have disabled it for the last 3 months and like the sound of just my 3 way scanspeak mains doing the duty and reproducing a 'phantom' center channel. I am not saying this is optimal for everyone but it is something to think about.

The second point is that if you are going to build and design a center channel speaker with the intention of building mains to go with this center on down the road, then think about a cohesive system. It is often recomended that 3 exact same speakers are the ultimate for L,C,R. If that is not possible then 3 speaker systems using the same exact tweeter and possibly mid will help maintain a similar tonal signature across the soundfield created by the 3 speakers. So you may want to choose carefully the mid and tweeter in a center design with an eye toward reusing them in the Left & Right design that may come next.

Just some early morning thoughts......... ;x(

Chuck

[JonW]

I don't want to be rasing a red herring here but aren't subwoofers in any HT setup really there for special effects
ie jurassic footprint

Heck, I don’t know. That’s why I asked the original question: How much bass should we design into a center channel? If you’re right, then we want center channels that are run full range and can play down to ~30 or 40 Hz. But most people run them with a sub. In which case there’s no major need to design them for ~30 hz output. I guess. Not sure, though. Hence this thread. (And hey, what’s the latest with your M8ta’s?)

The first point has to do with whether or not a center channel is really needed/wanted/neccesary. I have the same center channel as kg but have disabled it for the last 3 months and like the sound of just my 3 way scanspeak mains doing the duty and reproducing a 'phantom' center channel. I am not saying this is optimal for everyone but it is something to think about.

Hi Chuck,

A good point that I’ve heard before, from others. My own limited experience has been that things work better with the center channel in there. But maybe it’s because my left and right speakers aren’t as spiffy as yours.

So you may want to choose carefully the mid and tweeter in a center design with an eye toward reusing them in the Left & Right design that may come next.

Exactly. See my post below, in a minute.

[JonW]

So for you fellas who are running the various Dayton RS 3-way centers, do you think that they have enough bass output?

Let’s say I do a WTMW and keep with Scanspeak Revelator drivers, to match my other speakers, etc. What to use for the W’s? Let’s try a quick model for 2 woofers in a ~52 L sealed box.
The ~7” 18W/8531 shows it is down ~3 db at 60 Hz and down ~6 db at 40 Hz.

Stepping up to a ~10” woofer, the 26W/8861T reaches a little deeper and is down ~3 db at ~50 Hz and down ~6 db at ~40 Hz.

Is that extra bass really worth anything?
For comparison, the Dayton RS225 modelled at down ~3 db at ~53 hz and down ~6 db and ~40 hz.

If I go with the 18W woofer, I can use a smaller box and it’s a little cheaper. If I use the 26W woofer, I get more bass extension. But does that extra bass extension get me anything if I’ll be using a sub anyways? Is it a given that always using a sub is best?

So this brings me back to my original question: How much bass extension is best for a center channel?

[Curt C]

So for you fellas who are running the various Dayton RS 3-way centers, do you think that they have enough bass output?

Let’s say I do a WTMW and keep with Scanspeak Revelator drivers, to match my other speakers, etc. What to use for the W’s? Let’s try a quick model for 2 woofers in a ~52 L sealed box.
The ~7” 18W/8531 shows it is down ~3 db at 60 Hz and down ~6 db at 40 Hz.

Stepping up to a ~10” woofer, the 26W/8861T reaches a little deeper and is down ~3 db at ~50 Hz and down ~6 db at ~40 Hz.

Is that extra bass really worth anything?
For comparison, the Dayton RS225 modelled at down ~3 db at ~53 hz and down ~6 db and ~40 hz.

If I go with the 18W woofer, I can use a smaller box and it’s a little cheaper. If I use the 26W woofer, I get more bass extension. But does that extra bass extension get me anything if I’ll be using a sub anyways? Is it a given that always using a sub is best?

So this brings me back to my original question: How much bass extension is best for a center channel?

IMO, subs are not necessarily a necessity for HT. -It's just hard to get all those big refrigerator sized fullrange speakers daintily tucked into the corners of the room. :B -So ultimately, HT = sub.

But to attempt to answer your question, lets look at the effects of the receiver high pass circuit on all that hard fought for low-end extension…

I'm currently working with the 4-ohm version of the revelator you mention, the 18W/4531G, and since I've got that data handy, I'll use it in my explanation.

Sealed, with a Qt around .7, the driver models an f3/f6 of roughly 57Hz/43Hz respectively with a typical 2nd order rolloff. Assuming a 2nd order high pass from the receiver at 60 Hz, the driver transfer function becomes 4th order with an f3/f6 of 70 Hz/58 Hz respectively.

Compare this with the same driver vented but tuned to emulate the same 2nd order transfer function down to at least f10: The f3/f6 is now 42Hz/32Hz, but when the receiver 60 Hz HP filter is implemented, the f3/f6 is now 62Hz/51Hz

The vented design provided significantly more low-end extension, but when a typical receiver HP filter is applied, the f6 only changed by 7 Hz. This would suggest little advantage in the increased extension of the vented design when a sub is going to be utilized. It also suggests that larger drivers used with a sub may not be worth the additional size, weight, and cost of their smaller siblings.

The Revelators can kick out some impressive dynamics for their diminutive size, and suitably high passed, will provide a prodigious amount of SPL at low distortion. :T

C

[JonW]

Hi Curt,

Thanks very much for the thoughtful and insightful answer. :T

Your point makes total sense. Basically, once you put in the sub with the receiver HP filter, it kind of works out to be about the same. You don’t gain much from larger woofers and cabinets.

I do wonder if there is any good reason to run a center channel full range, either with or without a sub. If I’m going to the effort of designing a nice center channel, I could easily use the bigger woofers and cabinet, maybe venting, if I thought there was a good reason. But so far I’m not seeing any compelling reason. Although this thread has been helpful in that it convinced me to go WTMW. Then it’s a question of which W. The 18W drivers might well be all one would want in a center speaker.

I have to say that I’ve also been really impressed with the 18W/8531 that I’ve worked with. Not to mention the 6600 tweeter. It’s “only” an MT. The speaker is still new but, at this point, I listen to music without the sub. No need for extra bass. But as much as the bass and SPL output are, it’s the low distortion that I like the best.

We may get to meet in Iowa. I’m looking forward to the get-together.

[Silversmoky]

"So for you fellas who are running the various Dayton RS 3-way centers, do you think that they have enough bass output?"

Jon, I built the RS wtmw using the larger cabinet size and I used Curt's version of the crossover. It is a great sounding speaker. In my opinion it has a great amount of bass from the 2 rs225's. I usually have my sub on for home theater but have played around listening without it and there is still some very solid bass. Probably even enough to watch movies without the sub if that was the goal. Not sure in comparison how these would match up with some of the scanspeaks you are considering but maybe it gives you an idea. Hope it helps.

[---k---]

Jon,

I was going to post some thoughts, but then I realized it wasn't based upon much of anything other than conjecture and assumptions. What I think we should both do is set our centers to large and unplug all the other speakers. Then watch a few movies and see how much bass is coming from the center. One of those AVS Demo DVD's would probably work really well. I think this would be pretty convincing.

Screenshots from running TrueRTA or something would be really good too. I got the stuff, but haven't ever tried it. Hummm...

I'll report back.

[kgveteran]

This is where I use to be.The Quad Tumults would rollover to the Paradigms.The MiniMK3's had 6.5" midwoofers. There was a bug hole in the sound due to the inability of the 6.5 to keep up with the unholy subwoofer system.



Subwoofer to woofer or midwoofer is a displacement issue.At the XO point the mains must meet the subs with the same intensity or you have a mismatch.With (6) RS225's in the main channels I've gotten very close.

After a huge place of Sushi and a bunch of Labatts, our dinner guess's sat down for a concert...You guessed it Peter Gabriel Growing Up.The disc starts out kinda thin.By half way the sound is very full and strong, but the end it's perfect.My WTMW's kick butt.I could easily lower the XO point to 70hz or even 60hz with little trouble from the RS225's.Why stress out the 225's and burn off headroom.The combination is displacement and a proper XO point.

The surrounds have (1) RS225 and a RS28a in each cabinet and they kick butt too. Thats a total of (10) RS225's.

[JonW]

Jon,

I was going to post some thoughts, but then I realized it wasn't based upon much of anything other than conjecture and assumptions. What I think we should both do is set our centers to large and unplug all the other speakers. Then watch a few movies and see how much bass is coming from the center. One of those AVS Demo DVD's would probably work really well. I think this would be pretty convincing.

Screenshots from running TrueRTA or something would be really good too. I got the stuff, but haven't ever tried it. Hummm...

I'll report back.

Hey, don’t go to any effort on my part. It’s audio. Almost all we get is conjecture and assumptions. Oh, plus lots of ignorance. But yeah, some more info might not be a bad thing.

Jon, I built the RS wtmw using the larger cabinet size and I used Curt's version of the crossover. It is a great sounding speaker. In my opinion it has a great amount of bass from the 2 rs225's. I usually have my sub on for home theater but have played around listening without it and there is still some very solid bass. Probably even enough to watch movies without the sub if that was the goal. Not sure in comparison how these would match up with some of the scanspeaks you are considering but maybe it gives you an idea. Hope it helps.

This is where I use to be.The Quad Tumults would rollover to the Paradigms.The MiniMK3's had 6.5" midwoofers. There was a bug hole in the sound due to the inability of the 6.5 to keep up with the unholy subwoofer system.

OK, thanks guys. I’ll just go WTMW. It doesn’t sound like there’s any viable reason to do otherwise. So the only question remaining is which W to use- a 7” (e.g., Scanspeak 18W) or a 10” (e.g., Scanspeak 26W). And I’m not seeing any reason to go for the 10”. The 7” should be quite plenty if we’re always using a sub. I think this could make for a pretty potent center channel (all Scanspeaks):
For a tweeter, use the 6600
For a mid, use the ~5.5” 15W/8530-K00
For the 2 woofers, use the ~7” 18W/8531
Hmmm…

[---k---]

Jon,

No problem at all. It was something I needed to do for myself. I'm not sure how anyone can talk about bass from the center without doing this.

Anyway, I put in a couple of AVS Demo DVD's. Overall, I was shocked and disappointing at how little was in the center channel in many movies. It had me doubting the whole "the center is the most important channel" line you often hear repeated. Lots of vocals, but everything else varied. Where there was more than just the vocals, it often didn't sound as dynamic and like there was more being put into the right/left and/or sub. It seemed like there was very little, if any, deep extended bass (not that my center channel can dig that deep). It seems like in general the movies were mixed to have most of the bass in the sub and/or Left and right channels. Music DVD's, however, seemed like there was no attempt to shift bass away from the center.

I doubt that much from the center channel gets shifted to the sub with a 60 - 80hz crossover. But, I still think it is important to have a big or pair of big woofers to reproduce all that 100 - 25hz material. In your case, a pair of 7" Scans would probably do great.

These impressions are just from listening. RTA may change my mind, but that is going to have to wait for another day.

Some of what I watched:

Open Range, shootout scene - Lots of gun fire coming from the center. Doesn't seem as dynamic as with the mains on. Very little in the way of deep bass extension, but I don't think a single ~5" midrange would be able to provide the dynamics in this scene.

Flight of the Phoenix, plane crashing scene - Little if any identifiable bass.

Incredible Hulk, house exploding scene - Some deep bass from the house exploding.

Matrix, metal detector scene - the music is all in the right and left channel. it is weird watching it with just the center. There is a little bit of deep bass from Neo's first punch, but after that not much. Some bass from the slow mo. A lot of gun fire, but I'm not sure where it is in the frequency spectrum. But again, I wonder if a single small midrange could keep up.

Matrix, helicopter scence - a little more bass than before. You get some of the helicopter blades. But when Trinity hits the building, there is NOTHING.

Incredibles, rocket blast off scene - Lots of deep bass (of 3 seconds?) when the rocket is first getting moved into place. I thought that this was going to be it, but then as the rocket is launching it is pretty mild.
Incredibles, plane crash scene - the base for the flares going off was probably split equally between all three front channels and the sub. So, decent bass.

Ice Age, the nut breaking the ice scene - absolutely no bass in the center channel.

Master and Commander, cannon fire - the bell is fully in the center channel, but most of the cannon fire and explosions is elsewhere.

Lord of the Rings, ring drop - Some bass. There wasn't that massive bass that you get with the sub when the ring drops, but everything else there was some. That blue wave there was some.

Finding Nemo, glass tapping - bass.
Finding Nemo, whale swallowing - bass.

U2 Live, One - full guitar and vocal in the center.

Blue Man Group, whip it - full range in the center.

[kgveteran]

I still like the idea of the dual 15" flanking a Nat P.It would be a hulking cabinet.There would be little doubt that in the future you would ever turn down the volume during difficult scenes.It would provide a seamless transition between the subwoofers and the woofers of the WTMW.Ok , nuf said.

[JonW]

JAnyway, I put in a couple of AVS Demo DVD's. Overall, I was shocked and disappointing at how little was in the center channel in many movies. It had

Hey Ryan,

Thanks for having a look at that and reporting what you found. Interesting. It seems to me that the rear speakers hardly put out much info at all, in most movies. Even modern action movies use the surrounds, but not tons. So I would have guessed that ~80% of the sound is coming from the center. Maybe the soundtrack engineers put most sound into the center but all bass is routed to the sub signal. Idunno...

I still like the idea of the dual 15" flanking a Nat P.It would be a hulking cabinet.There would be little doubt that in the future you would ever turn down the volume during difficult scenes.It would provide a seamless transition between the subwoofers and the woofers of the WTMW.Ok , nuf said.

Can a 15" woofer match well with the RS180's of the Nat P's? How about Nat P + bass bins instead? And you'd be changing the baffle of the Nat P's by quite a lot, I'd think. If a center channel is designed properly, it should be able to handle all of the center duties well. And this thread is helping me figure out what a well designed center will look like.

[---k---]

Hey Ryan,
...
Idunno...

Me either.

Can a 15" woofer match well with the RS180's of the Nat P's? ...

I don't understand this whole driver matching thing.

If at your playback levels the RS180s can be kept within their linear, non-distorting range, then yes. If yes, they'll probably mate up nicely to anything. But, if you're driving them into distortion at your playback levels, they aren't going to match up to anything.

[JonW]

But, if you're driving them into distortion at your playback levels, they aren't going to match up to anything.

Yeah, if kgveteran is distorting them, I wonder if he's listening louder than what might be healthy.

kgveteran-
Presumably, you were in the military. What did you do? I know a veteran who was an artillery guy. After firing shells for 8 years, he can barely hear anything. If you don't have any hearing loss, you might want to turn things down. Otherwise you may end up with hearing loss. Then again, 0 db could be a meaningless number if it's not calibrated to a true 0 db (which is, what, something like 85 db?). You could actually be listening at 70 db or 90 db or anything in between.

[Curt C]

We may get to meet in Iowa. I’m looking forward to the get-together.

I’ll be the guy in the white lab coat and monocle.

-No, make that a loud Hawaiian shirt. I'll try and dress presentable. :rofl:

C

[Dennis H]

Can a 15" woofer match well with the RS180's of the Nat P's? How about Nat P + bass bins instead?

Pro-style 15" woofers can do it easily. They're really midbass drivers rather than subs. They can cross at several hundred Hz but don't go all that low so basically they would be big bass bins.

[JonW]

I’ll be the guy in the white lab coat and monocle.

-No, make that a loud Hawaiian shirt. I'll try and dress presentable. :rofl:

C

Hey wait. I've got a white lab coat. And plenty of loud Hawaiian shirts. Hmmm... If I want to dress properly for this event, I may have to go shopping for a monocle. : :W

[chasw98]

Jon,
Anyway, I put in a couple of AVS Demo DVD's. Overall, I was shocked and disappointing at how little was in the center channel in many movies. It had me doubting the whole "the center is the most important channel" line you often hear repeated. Lots of vocals, but everything else varied.

And this is why I was very happy creating a phantom center channel and not using my center channel (which is the same as kgveteran's) for the past few months.

Just as Ryan was spurred to 'test' his center channel, I was also. I found just about the same results Ryan did except I did not go into as much detail. I would almost have to say that center channel info as mixed in the modern environment is somewhat limited to the human vocal range and maybe, occasionally, a bit outside of it.

I used multichannel SACD's and DVD Audio discs for some of my center channel only listening along with a couple of movies. It was very interesting listening to The Beatles LOVE DVD Audio disc and only hearing John's voice come from the center. Maybe a small bit of ambience from mic leak but basically just the human voice.

I think a good point was made that a center channel needs to respond well to dynamics and a WMTW will fill that position.

Chuck

[JonW]

And this is why I was very happy creating a phantom center channel and not using my center channel (which is the same as kgveteran's) for the past few months.

Just as Ryan was spurred to 'test' his center channel, I was also. I found just about the same results Ryan did except I did not go into as much detail. I would almost have to say that center channel info as mixed in the modern environment is somewhat limited to the human vocal range and maybe, occasionally, a bit outside of it.

I used multichannel SACD's and DVD Audio discs for some of my center channel only listening along with a couple of movies. It was very interesting listening to The Beatles LOVE DVD Audio disc and only hearing John's voice come from the center. Maybe a small bit of ambience from mic leak but basically just the human voice.

I think a good point was made that a center channel needs to respond well to dynamics and a WMTW will fill that position.

Chuck

What I'm taking from you and Ryan is that the center channel has less info than we might have thought. In which case a high quality MT could well be plenty. But I guess we'll bump it up to a high quality WTMW just to make sure we are always over-engineered.

[---k---]

What I'm taking from you and Ryan is that the center channel has less info than we might have thought. In which case a high quality MT could well be plenty. But I guess we'll bump it up to a high quality WTMW just to make sure we are always over-engineered.

I think your first statement correctly reflects my current thinking. However, I currently disagree with. I'm sure all those people with HTIB and Boss would be happy with a simple little MT. But I want a center with more power to produce those big upper bass and midrage dynamics. I'm thinking particularly about the Open Range and the shootout scene in it. The gun fire comes out of each speaker. Very high dynamic peaks. A single small 5" and 6" producing everything from 80hz - 2khz, I'm just afraid won't be able to happily reproduce the dynamics like a pair of 7" or 8".

I think as your mains get better, your center has too keep up also.

It is pretty simple experiment to unhook your mains and sub and listen to just the center. I actually spent less than an hour doing it before was convinced of my opinions. YOU SHOULD DO IT! If you don't have any of the Demo DVDs, let me know and I'll make you some copies.

[---k---]

And this is why I was very happy creating a phantom center channel and not using my center channel (which is the same as kgveteran's) for the past few months.

Just for completeness, if you had left and right speakers of the same driver quality level, would you have left the center in?

It was very interesting listening to The Beatles LOVE DVD Audio disc and only hearing John's voice come from the center. Maybe a small bit of ambience from mic leak but basically just the human voice.
Chuck

Yeah, I found that too on a few. It's weird.

[chasw98]

Just for completeness, if you had left and right speakers of the same driver quality level, would you have left the center in?

I used to have the L, C, R as the RS WWMT's and the center as the companion WMTW. So they were all equally matched and I would routinely turn off the center and just go 'phantom'. I started trying this after reading from some 'hi end types' that they preferred phantom centers, so I thought I would try it.

Chuck

[JonW]

It is pretty simple experiment to unhook your mains and sub and listen to just the center. I actually spent less than an hour doing it before was convinced of my opinions. YOU SHOULD DO IT! If you don't have any of the Demo DVDs, let me know and I'll make you some copies.

Thanks. I have a couple demo discs and a few standard movies that are good for effects. I'll give it a shot later. My sub amp is out for repair at the moment. And I'm leaving town for a few days. After that I'll see if I find the same things as you guys. But it sounds like WTMW is still the way to go for the center. If the full capabilities of a good WTMW are used, you have it. If not, then you know that you'll never overtax the system and that you're always getting good sound.