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DXR 12 or 15 w/Subs for mains


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I've read through the content here on these speakers and after hearing them last night at GC am going to pick up a pair.
We currently have some budget Peavey 2x15+HF mud machines as mains, so we are really looking forward to the change. Running two 18" subs underneath.

I've read enough to understand that mains with 15s are not friendly to clarity and vocals cutting through. But my concern is that the 12s on top won't give us the power/punch that we want.

We're a rock / mashup / absurd 90s rap song band. PA carrys the full band - 2 guitars, keys, some bass, kick, snare... sometimes the full kit depending on how we're feeling. And vox, of course.

At $650, the 12s are much more what I'm allowing myself to lust after.

We recently played a few gigs at the pro football stadium here in town before a game and they ran subs and 12s on top. Sounded fantastic and full. So I'm thinking we'll be good. But need input. 12 or 15?

Help me spend my hard earned $$$. :-)

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I'd have to agree with aged. I have a pair of the 12's and considered the 15's which do have a bit better low end but decided that if/when we need that low end putting the 12's over sub(s) would be a far better solution. That said, I'm not sure the 15's are really that un-"friendly to clarity and vocals cutting through" but I can attest that the 12's are absolutely outstanding in that regard.

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I've seen other people say this too but I don't understand how 15s would be unfriendly to vocal clarity compared to 12s. Don't 15s generally have bigger horns and tweeters? Seems to me that the 15s would be just as good as 12s for vocals but with the bigger woofers they would be a little stronger in the low mids, which might be attenuated a bit with 12s. Then again, that's just what makes sense to me. I've found that sometimes what seems to make sense in theory doesn't always work that way in practice.

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I have never heard the DXS subs (they make them in 12" and 15"). Looking at the specs they appear to be very punchy around 70Hz : http://usa.yamaha.com/products/live_...es#tab=feature

Neither the tops or the bottoms have a real cross-over, but rather each has its own filter (LPF for the sub and HPF for the tops) which you are expected to match (ie if you set the sub LPF to 100Hz, then you need to set the HPF on the tops to 100Hz). This effectively gives you a cross-over wink.gif

Both the DXR12 and DXR15 have only options for 100Hz and 120Hz for the HPF. IMHO a 12" speaker can do just as much at 100Hz as a 15" speaker can and generally has better vocal clarity.

The reason for this is that the 12" speaker can produce higher frequencies better making the overlap easier to design to the HF Horn. Most people say that the vocals sound clearer with 12's over subs rather than 15's over subs.

Personally, I am surprised that the 15" DXR's don't have an 80Hz HPF (since the DXS's have a LPF at 80Hz).

So here is my thought.....

If you have your own cross-over and can put more of the LF to the tops (say around 80Hz) the 15" will give you a thumpier mix than the 12's will. If you don't do this, then the vocal clarity will be better with 12" over subs, and it won't matter which one you use with regards to how thumpy the mix is since both tops will adequately handle the 100Hz and above frequencies equally well.

I am always surprised how much "punch" comes from my DSR112 tops (using the 90Hz cross-over built into my PRX618S-XLF subs).

What subs are you currently using, and how are you setting up the cross-over? Do you plan on getting new subs?

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I have JBL PRX612m and PRX615m tops, with PRX618sxlf subs. Based upon listening to both combinations, the 12" over subs sounded a little "sweeter", and more pleasing to my ears. (I was using familiar recorded music of various styles for purposes of evaluation.) Without subs, the 15" sounded fuller, as you would expect with the additional low end. If the music requires subs, I will recommend that my client use the 12" tops. YMMV. Mark C.

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It seems to me that if you want kick in the mix, no 15" stand alone cabinet is going to deliver. If it adds some low frequency response, it's going to be nill next to what dedicated subs will give you. Especially after reinforcing the whole band. If you want the low frequencies to be reproduced anywhere close to the higher spectrum, you need subs, no matter how you slice it (in many rooms even 18" subs will have trouble producing the SPL the horns are capable of). Buy the 12"s and they're cheaper, smaller, lighter and just may sound better. I don't see any reason to by 15" cabinets.

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Thank you, all.
We are going to go with the 12s. Size, weight, cash, your input... All these reasons.
We do have a crossover in the rack, but I was hoping to just tap into the filter on the Yamahas. Do more w less.
The subs are 18" Eminence drivers in Behringer bx1800 cabs in series & driven by a Mackie 1400i. Which works well when not overheating...
Usually run them x.over at 120hz or thereabout.

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Quote Originally Posted by guitarman3001

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I've seen other people say this too but I don't understand how 15s would be unfriendly to vocal clarity compared to 12s. Don't 15s generally have bigger horns and tweeters? Seems to me that the 15s would be just as good as 12s for vocals but with the bigger woofers they would be a little stronger in the low mids, which might be attenuated a bit with 12s. Then again, that's just what makes sense to me. I've found that sometimes what seems to make sense in theory doesn't always work that way in practice.

 

Generally (very generally) 12'" give better high freq. response than 15"s. Matched with a sub (as the OP states), this provides for a pretty effective combination PROVIDING that all components concerned are high quality and run correctly. IME (limited as it is) there are seldom differences between the HFD's in a 12" 2-way and a 15" 2-way. Many times it's the same HFD's with (perhaps) a higher rated passive X-over. As many different approaches as there are speaker makers.
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Quote Originally Posted by agedhorse

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12's over subs is a good combination. I would recommend sticking with the dxr for both tops and subs

 

Do you prefer the DXR12/DXS15 top/sub combination to using another brand sub like a Yorkville LS720P or a JBL PRX618XLF with a HPF on the tops? The DXS15 subs are bandpass, very peaky and heavier than either of those, and would seem less versatile for use with other tops.
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Quote Originally Posted by undercool View Post
Thank you, all.
We are going to go with the 12s. Size, weight, cash, your input... All these reasons.
We do have a crossover in the rack, but I was hoping to just tap into the filter on the Yamahas. Do more w less.
The subs are 18" Eminence drivers in Behringer bx1800 cabs in series & driven by a Mackie 1400i. Which works well when not overheating...
Usually run them x.over at 120hz or thereabout.
Size, weight and cost are all good reasons, and the 12's over subs will do just as well or better than most 15's over subs.

Are you bridging the sub amp? That would be the most likely cause of the overheating (amp does not do well on sub duty if driven really hard into 4 ohms bridged). Also, you are most likely paralleling your subs, not series.
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I go with 15s for a few reasons. I have my subs in the center of the stage in front most of the time. The 15 lets me overlap the crossover point. Have the sub go up to 90hz. The tops go down to 75hz. Doing this the overall mix is fuller with the subs centered. If I only used my tops sitting on my subs then I guess I could use 12s. Not that 12s won't go down to 75 hz. I like the surface area a 15 has better. I also like having a 15 for a multi purpose cabinet. Great for different type or style of band. Do a Bluegrass show on a Friday night without subs. Full on Rock show Saturday with subs.
In general a 15 box is tuned lower.(DXR12 listed as a 52hz low response box,DXR15 as 49) A 15 inch woofer "in general" has a larger voice coil. (DXR 12/15 are the same 2.5 inch) A 15 inch woofer has more surface area which gives a higher spl all other things being equal. The DXR15 is 1 db louder than the 12. Not a big difference but that is part of it.
Looking down the road as your band grows having 15's to move to floor monitors,side fills, drum monitors, a 15 box would be handy to have. Yes its $100 more a box. But looking ahead it may be money well spent.

Dookietwo

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Quote Originally Posted by undercool View Post
Thank you, all.
We are going to go with the 12s. Size, weight, cash, your input... All these reasons.
We do have a crossover in the rack, but I was hoping to just tap into the filter on the Yamahas. Do more w less.
The subs are 18" Eminence drivers in Behringer bx1800 cabs in series & driven by a Mackie 1400i. Which works well when not overheating...
Usually run them x.over at 120hz or thereabout.
I would keep the x-over, but set it to around 90-100Hz (use your ears to decide what you like better). Keep in mind that the more LF you send up to the DXR12's the sooner you will hit clip and run out of steam on top.

The filter on the DXR12's will only keep the LF out of the tops, it will not keep the HF out of the subs (thus why you need the x-over).

If you want (and know how to do it), you could use the filter on the DXR12, and only send the x-over to the sub amp (where you would want to set it at ~100Hz).

You have 2 choices as I see it:
  1. Use x-over for the sub and send full range to the tops with the top filter engaged
  2. Use x-over for sub and tops and leave the filter on the tops disengaged

If you overlap frequencies, you will get cancellation issues as the two speakers fight each other on the same frequency range.
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Quote Originally Posted by OneEng View Post

If you overlap frequencies, you will get cancellation issues as the two speakers fight each other on the same frequency range.
If not set up correctly you will. If setup right you won't.
Crossovers are designed to have the drivers still producing the same freq. just at a lower level in the crossover area as their slopes roll off.

[ATTACH=CONFIG]350763[/ATTACH]

A crossover set at 100 hz with a (L/R) filter will still give you 100hz but the output is down 6dbs in the sub and in the tops as well. If the sub and top are in good phase alignment and in general are closer than 1/4 wavelength they will combine and you'll get a 6 db increase at the crossover point. This gives a flat response through the crossover area. There are many speaker companies that use both underlapped or overlapped crossover filters to get the best response in the crossover area.
You may have a sub that is very good in the 100hz range and a slope that is 6dbs down in the electronic realm will not give a 6 db drop at 100hz in accoustic output. So you would set the sub to 90 or 80 hz and have the top still at 100hz to get a smooth response at the crossover point. This is a underlapped crossover point.
Or you may have a top that is not good below 120 hz or so. A slope that is 6dbs down at 100hz will make more than a 6db drop at 100hz in its accoustic output. You would set the tops freq. at 70hz and still have a smooth response now at 100hz for an even response between it and the sub. This of course would be a overlapped crossover point.
When selecting a crossover point you need to consider the accoustic output of the driver at a given freq. The best type and slope of a filter to use. The phase response of the box itself and the electronic crossovers. Plus how the speakers will be placed in relation to each other as in distance apart, forward and back , to see if delay is needed to get them in good phase alignment.
No real golden rules when it comes to crossovers.

Dookietwo
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Quote Originally Posted by Dookietwo View Post
If not set up correctly you will. If setup right you won't.
Crossovers are designed to have the drivers still producing the same freq. just at a lower level in the crossover area as their slopes roll off.

[ATTACH=CONFIG]350763[/ATTACH]

A crossover set at 100 hz with a (L/R) filter will still give you 100hz but the output is down 6dbs in the sub and in the tops as well. If the sub and top are in good phase alignment and in general are closer than 1/4 wavelength they will combine and you'll get a 6 db increase at the crossover point. This gives a flat response through the crossover area. There are many speaker companies that use both underlapped or overlapped crossover filters to get the best response in the crossover area.
You may have a sub that is very good in the 100hz range and a slope that is 6dbs down in the electronic realm will not give a 6 db drop at 100hz in accoustic output. So you would set the sub to 90 or 80 hz and have the top still at 100hz to get a smooth response at the crossover point. This is a underlapped crossover point.
Or you may have a top that is not good below 120 hz or so. A slope that is 6dbs down at 100hz will make more than a 6db drop at 100hz in its accoustic output. You would set the tops freq. at 70hz and still have a smooth response now at 100hz for an even response between it and the sub. This of course would be a overlapped crossover point.
When selecting a crossover point you need to consider the accoustic output of the driver at a given freq. The best type and slope of a filter to use. The phase response of the box itself and the electronic crossovers. Plus how the speakers will be placed in relation to each other as in distance apart, forward and back , to see if delay is needed to get them in good phase alignment.
No real golden rules when it comes to crossovers.

Dookietwo
Hmmm.

It seems to me that overlapping the frequencies would cause more harm than good. You are correct that the cross-over frequency does not simply cut off everything else, but rather the cross-over point is where the cross-over has already lowered the output of that frequency by 10db (I thought). The slope of the cross-over (if adjustable) determines how rapidly the frequency drops off (typically 20db/decade to 40db/decade)
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Quote Originally Posted by OneEng View Post
Hmmm.

It seems to me that overlapping the frequencies would cause more harm than good. You are correct that the cross-over frequency does not simply cut off everything else, but rather the cross-over point is where the cross-over has already lowered the output of that frequency by 10db (I thought). The slope of the cross-over (if adjustable) determines how rapidly the frequency drops off (typically 20db/decade to 40db/decade)
The basic analog electronic crossover that most use has a 24 db per octave (80 dB/decade) Linkwitz-Riley (L/R) filter which is defined by its 6db down point. Set the crossover at 100hz and at 100hz the signal is 6dbs down from the rest of the bandpass. Other filter types like Bissel may be defined by their 3db down point. Crossover with bissel filters set at 100 hz will have the freq. down 3dbs. Of course there is also Fir type filters which yield very steep slopes as the yamaha speakers have. The Order of filter type determines the slope. 1st order,2order,3rd etc yields different slopes. Mixed order slopes can also be used.
Needing to overlap or underlap or not to do it at all is all up to the overall frequency,phase,amplitude, and location of the drivers being summed.

I used Smaart software and find its a good tool to check and align drivers.
http://www.rationalacoustics.com/files/case3.pdf
http://www.rationalacoustics.com/files/case6.pdf
I tried aligning my Mains to a very loud drum monitor before and it did work quite well.

Some good basic reading here.

http://en.wikipedia.org/wiki/Audio_c...order_or_slope

I did find a Underlapped alignment paper.
http://www.excelsior-audio.com/Publi..._Alignment.pdf

Dookietwo

Edit: Undercool , Sorry to go off topic!
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Quote Originally Posted by agedhorse View Post
I rarely find that overlapping or underlapping is necessary, desireable or productive on a reasonably well thought out speaker system. Where it MAY yield some benefit is making up for some gross flaw... like a bandaid.
Andy;
What measurement system do you use when you check these well thought out systems?
Doug
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Quote Originally Posted by Dookietwo View Post
Andy;
What measurement system do you use when you check these well thought out systems?
Doug
Note that I am making a generalization here, that most folks who "think" they need to go to such esoteric lengths in fact probably are better served addressing the more real problems. I am not saying that under some (not the majority) of applicartions there may be SOME benefit, but often this is better resolved by looking deeper into what may be the root of the problem rather than junping to this as a solution. Also, it should be noted, underlapping was much more common and necessary when BW x-over filters were more commnly used because they were not constant power summing (because of the squared factor in the power versuis voltage equation), but with LR alignments, this was handled mathamatically within the filter formulas (and IIRC the Q of the filter corner is lower).

I usually use IASYS which superimposes coherence information within the RTA plot. I use this primarily because the testing I do to develop speaker ratings requires some method of calculating power compression and IASYS has a practical non-destructive algorithem for doing so, and outputs data in a way that my legacy management system can handle. I also use the Audio Toolkit suite for casual use but plan to do more with this as I modenize my system. I am not a great fan of Smaart (too many ways to get data that looks good but contains errors or masks problems) but when the data is good, it's just as viable as anythig else.
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To the OP,

There is an engineering axiom that I personally really like:

KISS: Keep It Simple Stupid
For the VAST majority of users, messing around with the cross-over settings in anything other than the cross-over points is simply asking for issues.

There are those here that are both engineers and sound professionals who can do this and achieve good results. The rest of us have a much better chance of getting worse results rather than better wink.gif

Your BEST option is to use the cross-over for both the tops and bottoms. While you are at it, it is also beneficial if you cut out everything
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Quote Originally Posted by agedhorse View Post
Note that I am making a generalization here, that most folks who "think" they need to go to such esoteric lengths in fact probably are better served addressing the more real problems. I am not saying that under some (not the majority) of applicartions there may be SOME benefit, but often this is better resolved by looking deeper into what may be the root of the problem rather than junping to this as a solution. Also, it should be noted, underlapping was much more common and necessary when BW x-over filters were more commnly used because they were not constant power summing (because of the squared factor in the power versuis voltage equation), but with LR alignments, this was handled mathamatically within the filter formulas (and IIRC the Q of the filter corner is lower).

I usually use IASYS which superimposes coherence information within the RTA plot. I use this primarily because the testing I do to develop speaker ratings requires some method of calculating power compression and IASYS has a practical non-destructive algorithem for doing so, and outputs data in a way that my legacy management system can handle. I also use the Audio Toolkit suite for casual use but plan to do more with this as I modenize my system. I am not a great fan of Smaart (too many ways to get data that looks good but contains errors or masks problems) but when the data is good, it's just as viable as anythig else.
I've looked at the IASYS system. Maybe around 2007 or so. Nice unit. An all in one box that makes setups easy. Saddly the around $4000 dollar price was just too much for my wallet. Not sure of its price today. Its funtion to look at power compression is a very useable feature. Power compression is overlooked in most cases. Smaart is fine if you have a handle on what to look for and know when the measurements are not right when the results come in. A reading of 320ms delay time when your only 10 feet from a speaker needs to be redone. :-) But with time like anything you can get easy, repeatable, reliable results.
As far as underlapped,overlapped, mulit tapped crossover filters, filter types and delay etc. Its all up to the loudspeaker designer, or user as to the best correct approach. I wouldn't say it is used to correct an inherently bad speaker system but more as a way to make them work well or behave in the band pass area they are reproducing together.
Its becoming more and more common and a widely accepted process regardless of speaker brand or $. Processing in speakers systems is as common as electonic controling systems in most cars being driven today. Line arrays and other speaker systems use these to control directivity among other things. But I guess I'm telling you things you already know. Even the Yamaha DXR series boast of phase and time alignment in their speakers. I've heard both the DXR and DSR and they do sound good.
As I mentioned. Underlapped or Overlapped and all the other processing that can be done to a speaker is a matter of if Done right it makes a good system better. If Done wrong then its of course a worse sounding system. Some say keep it simple which is fine. Its just what is "simple" is defined differently person to person. Some people can design a bass guitar amp while others have all they can do to plug one in. For me to keep it simple is to buy a guitar amp and settle for the features it has. For you to keep it simple is to design and build one that suits you needs with no limitations. For me setting up a speaker system using correct processing to get the results that I want from it is like you designing an amp.

Have a Merry Christmas Andy;
Doug
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You too Doug.

I just finished writing some DSP presets for a manufacturer recently, alignment was plenty good with pretty simple processing. Starting with inherently good makes the correction process much easier and ultimately the end results better (for the most part).

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Hey Doug,

I wasn't suggesting design specifications, but rather usage suggestions with regard to setting up a FOH system.

I am afraid that most people who do sound for a band wouldn't have the vaguest idea what S.M.A.R.T is wink.gif

You guys are pretty heavy on this stuff wink.gif It is nice to have such experience here.

Oh, and of course, Merry Christmas guys smile.gif

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Quote Originally Posted by OneEng View Post
To the OP,
...
Your BEST option is to use the cross-over for both the tops and bottoms. While you are at it, it is also beneficial if you cut out everything
This is going to be the plan. We are going to keep, for now, the subs we have and use our crossover as previous. We DO have the rig set up to cut off those ultra LFs using the cutoff in the poweramp.

We toyed with picking up the 15s (based on more low end available and still delivering on the mid range clarity (or so they say)) on the chance we ever do some smaller acoustic / winery-type shows, but the 12s won out.

With $100 off, we can get them @ $599 ea. Tax here in the Peoples Socialist Republic of Cuyahoga County is almost 8%, but that still gets us out the door at $845.

Closing thoughts accepted. And thank you much for all the input and discussion.
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One last thing.
I was continuing to read on this subject and came across a topic I started in 2010. Many gigs and two bands later, I am finally taking all of your advice. A few things from the answers I got back then:

"...at the price point of buying 2 new... I'd hold off and save more money until you could spend $500/spkr and not for the pair."

"Take the advice you're getting here... upgrade the speakers, go powered for mains if you can and relegate the passive stuff you have to monitor duty."

"That's not a very inspiring audio pile. Yes, it should work adequately for small bar gigs, etc., but you should put a priority on upgrading the speakers before upgrading anything else. Speakers make the system, period."


Advice TAKEN.

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