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Discussion Starter · #1 ·
I recently finished my E-wave SRs, and they're outstripping my low end in my media room. I started discussing options in the E-wave thread, but this discussion deserves more direct attention.


My room is a second floor dedicated media room, 18x22x9, with a 18" deep false screenwall, that flares to 24" deep at the sides to house media/component cabinets.


I currently have a Tempest x2, slot ported to 17hz in a 6.3cuft box (24x48x13) that fits behind the framing for the screenwall - to allow lateral movement/placement. It's driven by a Dayton HPSA 500w amp. I realized recently it's being driven to soft-clip during bass heavy music, and moderately spirited listening levels during movies - with or without Audyssey engaged. Being on a second floor, with attic on 3 sides and the ceiling, I have pretty minimal room gain (I have a big dip in REW from 10-20hz). I was pretty surprised to see it soft clipping, even though the couch was vibrating with notes a bit, and it is capable of making the projector image blur as well...


Well, I want more. More bass, cleaner bass if possible (who doesn't?), and help evening out the terrible modes I have. Best position for the single sub for smooth frequency response is about 1/4 way from the corner as shown in the pics. Placing the sub in the opposite location produced a mirror image in modes across the seating position, so hopefully 2 subs should be pretty smooth. My original plan was just to add a second of what I've got until I realized the clipping issue, and I'm concerned another ported tempest will help with response, but may not give enough headroom to deal with the clipping.


I have 14" depth behind the framing which is the limiting factor (16" if it rides on top of the framing, but that limits lateral position quite a bit). OR, I have a 16x16" footprint for something tall and skinny (e.g. 15" dual opposed) right next to the cabinetry, as shown on the sketchup model and where the old tower mains are seen in the photo.


Budget: 500-1000 for drivers/amps/eq. I have one 15a circuit for all the components now, and can muster up one more 15a if needed for more power. The only EQ I have now is with Audyssey Multieq.


Options as I see it are multiple single sealed in 15/18", dual opposed 15", another 15" ported, slender horn, and IB (2x18"). PR is out with large flat boxes, there's no way to oppose 18" PRs. I'm reticent to do the IB, as I'm concerned there would be a dramatic increase in sound spillage to the rest of the house, which would detract from my otherwise great relationship with my Wife, and her patience in this nearly finished room (1 year in the making and counting).


How would you spend my money to get the most bang for the buck? Oh, use is 95% HT, 5% music. I had considered a CHT 18.1 or HSU vtf15 but they can't be shoehorned behind my wall, and besides, I've built all this, what's one or two more subs?



C.

 

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I see that you set the middle section of the screen wall back a bit (just like mine) if you brought it out 2 inches you could shoehorn in a couple of LP THTs. That is my current plan but I'm curious to see what the geniuses here come up with.
 

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The easy way to do it is exactly what EV said; build another of what you already have.....6+ more dB (with more powerful amp) plus smoothing of response between seats....win, win.


If you want me to work up a quick model for a horn-loaded solution, it would not include the Tempest driver.....


If I were you, I wouldn't even think about horn loading....unless your budget is really constrained. I'd pick up 3 more tempest drivers and build 2 dual opposed boxes (or 4 single boxes), get a minidsp and an EP2500, and use an LT function to get the most clean extension possible. A bit over $1k, but in my opinion, well worth it. It sims out at 110dB+ from 10Hz on up, climbing quickly above 10Hz, over 125dB at 20Hz, and over 130dB at 30Hz, if corner loaded, before room gain.


I think of it this way; if you have the budget, it is very hard to beat IB or sealed, with vented being right up there with them. Horns rule when you need tons of spl within a certain passband at low distortion, AND you have space to spare, which you really don't....


If I were to draw up a horn loaded solution for you, I might go with 4 smaller horns than with 2 larger ones. Gimme a Hz target and exactly how big the boxes need to be/can be, and I can crank out a sim pretty quick.


JSS
 

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Couldn't resist a quick sim, Four 300L horns vs Four Tempest X-2, all enclosures corner loaded and at Xmax:




The horns leave almost 5dB on the table without a highpass.


The 4 Tempests need around 2000 Watts, the 4 horns need less than 500W, if highpassed, around 900W.


The 4 horn drivers will be less than $700, the 3 Tempests under $900.


Given your needs and space requirements, I'd still do the Tempests over horns......


JSS
 

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Discussion Starter · #7 ·
I appreciate the input so far. I'm trying hard not to redo my screenwall, and I don't really have enough space to do horns well. I can't corner load them (my cabinets in the true corners of the room), and I can't move them at all if they don't work well in those specific locations.


I like the idea of just upgrading my current Tempests. I have been mulling over some Winisd sims, and here's what I came up with, all driven with enough power to approach xmax. These graphs are:


Four Tempest x2s sealed with an LT circuit ~1500w (either dual opposed or separate, knowing I'd lose a few DBs from non-colocation on any of these graphs). YELLOW


Two Tempestx2s ported (like what I have now, but 1 more and more power) 17hz tune, 17hz highpass, 2200w, BLUE


Two Malxs sealed with an LT,2200w, RED


And interesting to me, a setup I haven't really seen used, but modeled well - Two Tempest x2s, ported to 11hz, and an 11hz highpass,1300w - GREY. This models really well to dig deep to 10hz like a sealed, but some of the extra efficiency of ported - besting the performance of the quad sealed Tempestx2 or dual Malx above 10-12hz. What's the disadvantage of this alignment, other than finding the circuitry to handle a low HP filter like that? Will the miniDSP allow this option? The group delay on this alignment goes through the roof (~ 150ms), but I don't know what that equates to in real world listening.


None of these SPL graphs account for any room/boundary gain.


Mucking with numbers in WinISD is easy, but sorting out the real world consequences of these decisions is above my pay grade.



Thoughts?


 

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Those are all good options; personally I'd go sealed. BTW - corner loading depends on frequency. The lower the frequency, the further the sub can be from a corner and still get corner loading. For horns, this is very fortunate, as they need the most help down low.


JSS
 

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I think it depends on how deep you want to play. If you are satisified with your 17hz tune, I'd build an matching sub and get a bigger amp. Throw in a minidsp and you are golden.


If you want more depth either build larger lower tuned boxes for 2 T-Xs or do 2 dual opposed Tempest-X's. You might as well use the driver you have. Short of the AE AV15 series I don't think there is a 15" driver that would give you much improvement...and the AV15s aren't in stock AFAIK.


One other option, albeit more costly, would be to use your T-X in a PR box with 4 opposed PRs in shallow tall boxes. The T-X could face forward. Some people claim a PR alignment has SQ advantages over ported YMMV. I haven't modeled it but I'd imagine using 4 of the AE PR15-1400s would give you a nice low tune in probably 200-300l. Those PRs are $70ea so that would add $560.
 

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Discussion Starter · #10 ·
Still been running a lot of sims, and haven't completely ruled out out IB.


When modeling IB, what to use for the box size, in my case? I have a large attic that has fully vented soffits. 2000? 200,000? 2,000,000? Same as the room size? Going up to ridiculously large "box" sizes affects output significantly, but there has to be a reasonable limit to modeling an IB...? Quad IB3s is going to put out well more than 95db, I reckon.



Still messing with dual/quad IB3s, dual q18 sealed with LR (less expensive with near the same output as quad tempests, with lower Q, and I can sell the existing Tempest), or dual Tempests ported to 17hz. I've read some results of low tunings losing out on sound quality relative so higher/mid tuning, so I'm probably going to eliminate the low tune tempest option.


All my choices so far need a larger amp, and for sure the sealed needing a minidsp to create the LR. With IB or ported, I plan on seeing what Audyssey can do before needing to invest in a separate EQ.


Best,

C.
 

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Quote:
Originally Posted by stgdz /forum/post/19618936


there is ok's new SDX horn

78" x 40" x 13.2

http://www.avsforum.com/avs-vb/showthread.php?t=1275278

Two of them might do it and should be in budget, but I still haven't gotten the thing together to see how it does in reality. If the OP really wants to give an untested design a try, I suppose I can let the plans slip just this once. I'm on the laptop at work right now and can't check the sims, but IIRC 350W in was showing 116-117dB at one meter down to about 17Hz or so in half space for one horn below Xmax. Knowing what I know now about my first TH, it will take more power and get louder than the sims suggest. I just don't know how much more.


One EP4000 should be able to handle two of them. I'm going to be feeding mine 900W at 2 ohms... not sure it'll take the whole deal without making bad noises, but it'll handle a good deal more than the 350W Hornresp says, I'm quite certain. My last build is getting 1100W and liking it, much to my amazement.
 

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Discussion Starter · #12 ·
Quote:
Originally Posted by Oklahoma Wolf
Two of them might do it and should be in budget, but I still haven't gotten the thing together to see how it does in reality. If the OP really wants to give an untested design a try, I suppose I can let the plans slip just this once. I'm on the laptop at work right now and can't check the sims, but IIRC 350W in was showing 116-117dB at one meter down to about 17Hz or so in half space for one horn below Xmax. Knowing what I know now about my first TH, it will take more power and get louder than the sims suggest. I just don't know how much more.


One EP4000 should be able to handle two of them. I'm going to be feeding mine 900W at 2 ohms... not sure it'll take the whole deal without making bad noises, but it'll handle a good deal more than the 350W Hornresp says, I'm quite certain. My last build is getting 1100W and liking it, much to my amazement.
Thanks for the offer, but I think I've ruled out TH designs. I don't quite have 40" of width between my mains (or if I do, not 1mm more), and at least with my current sub, placement closer to the cabinets gives a more smooth in-room response.


Best,

C.
 

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Discussion Starter · #14 ·
Looking at adding a second tempest x2 - likely another ported enclosure.


Is it worth it to go the pro amp route? I have an HPSA 500 right now, and looking to either replace it with a EP4000 and minidsp, or just get an Oaudio 500, and a minidsp for eq.


As I see it:

EP4000 - 650w/ch, large, needs fan replacement to make it quiet (yet is it really silent? I don't have a separate closet with a door), cost: ~$360 with fan. Could run the drivers sealed/LT or ported, though 2 15"s with an LT won't improve the output I have now above 20hz. Possibly sell HPSA 500 for ??? Still sorting out the gain structure possiblities/problems of using my Denon receiver and a minidsp with the EP4000.


Oaudio500: $225, silent, >450w, built-in highpass. Ported is the only option (as the highpass in the HPSA is non-defeatable).


For an extra 150w, is the EP4000 worth the extra expense and hassle with noise management? If I were going quad sealed and had a 4ohm bridged load, it might be worth it - though a single EP4000 would be underpowering 4 tempests pretty severely anyhow...?


Oh, and anyone know what the HPSA 500 really puts out? I have never been able to find that despite multiple searches.



Thoughts please?


Thanks,

C.
 

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Discussion Starter · #15 ·
Dragging this one back to the top. Thought I had it all worked out - another Tempest x2, Oaudio 500, constructed while my wife was away on vacation...



However, the tempests are gone for good (no more Tempests, Shivas, or Mal-Xs to be made).
And I held of on the MFWs as I had planned on just adding a second Tempest. AND, the LMS-Rs are flat out ridiculous in price now.
Ah well, I snooze I lose.


Any options out there for a comparable sub to play nice with my Tempest? I saw the listing for an SDX 15 and that looked like a viable option... (anyone care to model that next to a Tempest x2 - pretty please?). Primary goal - smoothing response in the room. The single sub already vibrates my projector/mount enough to blur the picture.


My biggest issue with building a sub is space. Height, no problem (up to 30", width, no problem (up to 48"), depth - problem. I have 15-18" max behind my screen wall, and I'm not rebuilding the screenwall.


I was hoping to stay in the same ballpark in size - 6-7cuft ported build. All the good horn builds are DEEP. Also, doing a pair of something behind the screenwall and relocating the Tempest into an end table design is viable.


Thanks in advance for the help brainstorming. Oh, and for the next few weeks my wife has the laptop with WinISD out of town, and I'm stuck with the MAC which makes box modeling impossible - curse you Apple!


Best,

C.
 
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