Hey all- I read with the summas that there is a minimum recommended listening distance of ~2m does this apply to the SEOS stuff as well (to some extent)? Am I correct to assume that a SEOS12 with a 10 would need less distance for the sources to integrate than it would with a 12? My closest distance is about 1m (maybe just a little less) and looking at the measurements I've seen there don't seem to be any problems in the plots @1m. The plan is to make the two parts in separate boxes with the woofer on top and seos in the middle and a bass driver below (IE focal utopias) with the angles adjustable between them. It would seem to me if there was an issue close up this could be a way to help address it. Any thoughts on that? Eyeing the AE TD woofers my preference would be a 12 for the higher sensitivity and lower extension but one thing that isn't clear is if a 10 or a 12 generally speaking is actually a better directivity match for an seos-12. Thanks
You're 1m away! You're going to have your head in a vice and have WAY to much speaker. 2m is much more appropriate. At that listening distance you're better off with a 6 over 6 or even a 5 over 5 to get closer driver spacing. At that distance, I imagine the direct sound will more than trounce any reflected sound, so directivity isn't all that useful. Much more useful is have a directivity match with a very wide vertical lobe. Something like this: http://techtalk.parts-express.com/showthread.php?234188-More-love-for-the-iron-driver!-Topped-with-the-ND28-in-a-waveguide except you can't get that waveguide. How loud do you want to play at 1m?
I would really recommend doing them as 2ways to use with subs placed separately. Bass depends on, more than driver or box quality: location, location, location. Take the worlds best sub driver in the best made cabinet, and put it in the wrong place in the room and it will flat-out SUCK. Location of the upper frequency drivers is already restricted by other factors (image location, appearance, room arrangement) and there's not much chance that will also be the best place for the subs. For directivity match, either a 10 or a 12 should be pretty comparable (maybe cross the 10 a little higher). Minimize ctc as much as you can. Tilting the separate boxes ala Focal won't improve ctc noticeably (not as much as the spacing from extra cabinet walls will hurt it).
How about an EOS 6(http://www.diysoundgroup.com/waveguides/other-waveguides/eos-6.html) over a quality 6" driver? Although, for nearfield I would prefer a coax speaker such as KEF or Tannoy.
Thanks guys- So I measured and it's more like 60 inches so 1.5M, (duh should have done that first). This for a smaller recording studio so being nearfield up front is actually desirable. I'm also a composer/producer which makes being too far away a problem regarding cumulative latency between the software and the distance when playing an instrument. Currently I have JBL LSR-32's which claim to have a 60x100 dispersion above 2.2k but from what I measure/hear they aren't nearly so smooth off axis as the SEOS especially vertically (above XO). @Tux- I don't know about a vice, but up front the position is fairly restricted in terms of where my keyboard and mouse is anyway. But the 1.5 distance isn't the only one. I usually move back to listen and also have clients in the room to think about, the back couch is probably ~4M. I have a ipad remote so I audition and make mix changes back there as well. @Bill- Yeah I have two more subs I can play with, there isn't a lot of room for placement in here and I do have a massive amount of broadband absorbers (1.5ft superchunks and full 4-8" 703 wall coverage with slats over that and clouds on the ceiling with diffusers). Of course that doesn't make placement a non-issue but less of one. So my thinking that aiming the beam of the woofer to merge with the beam of the tweeter closer to get closer integration is erroneous? Or at least less important than C2C spacing...good to know that should make building them easier also. In terms of SPL's my short answer is yes please! With material with no dynamic compression applied yet it takes a lot of overhead. Even to monitor a drumset @85dB on a spl meter the LSR32's sound pinched trying to reproduce the peaks that are 35dB+ above the average. They are rated to ~110db @1m with 1dB of power compression so it would have to do better than that. Which is why I was looking at TD12M + SEOS12. Again any thoughts would be appreciated. Thanks
Ah, that explains things much more. I think a SEOS design will work nicely for you then. 1.5m is still pretty close, but unlike Geddes' speakers, the SEOS isn't very tall. And you'll definitely have your dynamics.
Plus a SEOS based speaker will have a shorter center to center distance, allowing them to be placed closer than Geddes'.
I think you should take a step back and look at this as trying to solve a specific problem. It seems your requirements are recording studio monitors at 1.5m that are capable of minimal compression on 120db peaks, right? If you can answer these questions we can probably help better: 1. Budget? 2. Active DSP or passive crossover? 3. Are you willing to take measurements so you can be assisted with design of either passive or active DSP? 4. Will these be in free space away from boundaries or mounted in a soffit? 5. How big can the speakers be? 6. Are you planning to use separate subwoofers? 7. Can you post pics of your present setup? Face, Tux and Bill are on point with their answers, but I think you probably want to get this more precise since this is obviously more than just HT use. Something like the Daniel speaker designed by Bwaslo might be a good option. You would likely need more stout mid drivers though to give you the dynamic capability you want, but that general design type should work better at close range due to a wider vertical directivity. Assuming you have the budget I would use dual B&C 6NDL38's. They should exhibit very little compression and will be very low distortion as well. They will require some sort of subwoofer system though. I would suggest flanking subs for a studio setup. Something like 2 pro 18" woofers in ported enclosures able to play flatly down to the lowest frequency you will mix. The advantage of using pro drivers is that they will likely exhibit less power compression. One way you could do this would be with a hybrid passive/active DSP crossover. You would design a simple passive primarily to divide and crudely shape the mids and SEOS. Then use something like a MiniDSP to blend the mid/SEOS portion with the bass portion. The MiniDSP could also be used to tweak the mid/SEOS response to your room and ear. To truly help guide you to the best solution, some of the questions above would need answers. I would be willing to assist in design if you are willing to measure. I think it would be fun. One other thing. GranteedEV's suggestion of a Danley Synergy clone might actually be the best performing solution. That approach can be used from anything as near field as a foot to far field in a PA setting. The tough part is construction and design are fairly difficult. Bwaslo does have a great thread and spreadsheet to help though if you are willing. I can't think of a better approach to studio monitors.
Hey Coctosan Answers to your questions- 1. Probably 1500 for this part, drivers boxes, xo if I go hybrid. I have amps and everything I need for active up to 8 way. I might have to sell some stuff I have and buy something else but I'll count that as separate in the budget. 2. Active or hybrid. I have a mvc1, dacs and amps for active Dsp with plugins in pro tools. So either just a hpf to protect the cd, or maybe hybrid. 3. Oh yeah I'm a bit of a measuring nut. All set to go on that. 4. Free space, they are in corners and the walls are covered with 4in 703. The back wall is made out of blocks of cellulose, I could take it apart but I'd rather avoid that. 5. I don't have a lot of depth without changing the room a lot, the easiest would be 14" deep, 26" wide 8ft tall. 6. Yes, working on a pair with w15gti's that could be stands for the seos12 & 12. I also have another pair of 12" subs. The room is well treated and I don't have a lot of problems getting say 20 measurements to within +\- 3db from a flat tuned spatial average. From 20-200 with no smoothing. 7. Sure ill do it when I have a minute.
Is that $1500 for a pair of speakers (wood, horns, drivers, misc) or per speaker? Either way, that is a good budget. Since you also know how to take measurements this shouldn't be too tough. You can definitely do a full active 3-way or even 4-way. This is what I'm thinking: SEOS-15 with DNA-360 ~$150 2 B&C 6MD38-8 ~$160 total (http://www.parts-express.com/pe/showdetl.cfm?partnumber=294-651) 1 TD15M ~$310 ---- ~$620 + ~$100 for wood and some speakons The mids would be side by side beneath the SEOS-15 crossed around 1000-1200hz. The mids would cross to the TD15M anywhere from 200-400hz. You will have no vertical null issues. Horizontal directivity should hold well down to ~1000hz. This setup would be about as minimally compressed as you are going to find. At 1.5m I would be surprised if you could measure any compression at 115-120db with this setup. The B&C mids are true midranges, not midwoofers. They will only play down to ~200hz and I'd probably only push to them to ~300hz. They measure very well and are highly sensitive with excellent power handling. Some very well respected designers use them as their favorite mids. They seem to be a damn near exact clone of a PHL1120 but reasonably priced. You should be to run the TD15M's sealed and tweak to blend well with your W15GTi's. The W15GTi's should work very well. You should be able to get this thing perfect with Pro Tools plugins although it is something I've not messed with. If it is within your budget, you could definitely do full DSP active. I would just put a large cap on the DNA-360 for protection. It sounds like it won't cost you more to go full active. There are some other driver options you could try as well like the BMS 4550 for the CD and the 18Sound 6NMB420 for mids, but I doubt it is worth the expense. If anyone else in the peanut gallery wants to chime in on this proposal, I'd love to hear it. Keep us posted.
Seems like a waste of a TD15M to cross it over at 400Hz or below. Lots of woofer can do that just as well if not better. The M versions are known for midrange.
That is a good point. There are really a countless woofers that could work well. The key is getting something that exhibits minimal power compression. A TD18h would well. It depends on how big the speaker can be and the budget. It also depends on how much amp power is available. Going with more sensitive drivers generally leads to less power compression all things equal. Maybe a B&C 15SW115?
This may work well in that application: http://www.sbacoustics.com/index.php/products/woofers/15-sb42fhc75-6/ http://www.madisoundspeakerstore.com/approx-15-woofers/sb-acoustics-sb42fhc75-6-15-woofer/
1500/pr I suppose, really it's also a question of how soon, if making it 3k/pr would really be worth it I could be convinced to do that, but it would be a lot longer before I can use them. 1500 I can swing nowish. Is there any difference in vertical pattern control with dual 6" vs a single 12? the measurements on the Daniel look really good, did anyone get tests off axis vertically? The malcom looks a little less controlled as you move up and down compared to with a 12 so that's why I'm asking. I would rather it be at least smooth off axis vertically so if someone is standing it my have some hf roll off but not a lumpy response. What other pro's and cons are there to dual 6 vs single 12's other than the obvious ones? Based on the measurement I've seen on the w15's: http://farm5.static.flickr.com/4003/4383499824_6552a657ba_o.jpg I think it would be a shame not to let them play a little higher than you might normally with a sub, disto is great from 100-200. I'm thinking a 12dB/oct with a low pass corner freq @ 100hz will be enough to keep that 450 distortion spike down. But I'm building them first so I can verify that, if they are only good for true subs I'm ok with that too (I got a pair for $400). If it does work out that high I think a more efficient mid bass makes more sense like a td12m or faital 10fh520 or even a pair of 6ndl38's compared to true mids? Why have the mids go up to 6k when that is the SEOS's turf anyway? The TD18h+ looks amazing but I don't have space for the boxes. All things considered td12m seems to keep coming to the top of the list... Whatever driver(s) spans ~100 to ~1000, one thing I would like to try (in a quick test box first) would be a OB with the back sealed up with caulked in mass loaded vinyl and 703. I think it should be possible to kill the back wave almost entirely with no chance of it reflecting through the cone down to 100hz and then achieve a graceful infinite volume-esque roll-off. But that theory will require testing.[/size]
Face- That SB Acoustics driver is rather expensive for only being to handle 300w and having fairly high inductance. It also seems their sensitivity spec is bogus. They list it measured at 2.83v but it is not an 8ohm driver. It should be measured with less voltage and would likely be about a 89-90db driver. I don't know a great deal about SB Acoustics drivers outside of the spec sheet, but I don't think they will handle power compression nearly as well as good pro drivers. This application also doesn't need the woofer to cover much below 80hz either. Ryan- I think you can do $1500/pr easy. I was just trying to clarify. I'm not sure I would change my recommendations much if your budget was double. There are a few reasons I suggest going with the dual pro 6" mids. First, it moves the center-to-center distance between the mids and SEOS much closer. By doing this you minimize phase issues with sitting rather close to your speakers. If you were sitting >2m back it wouldn't make much difference. JBL uses a separate small midrange in your current monitors for similar reasons. The tight also pretty much eliminates any vertical null issues which means you will be able to move around a bit behind your console without concern about significant response anomalies. The vertical response will be more uniform. The other area of benefit is that by using dedicated mids that don't produce content below ~200-400hz you don't suffer from intermodulation distortion. For drivers this size, it requires very little excursion to cover ~200-1200hz. If instead you used a single driver to cover ~80hz-1200hz it would need to move a few mm to cover higher levels around 80hz causing IMD. This isn't an absolute requirement but a nice benefit. There are other benefits like mitigating power compression (dual 6MD38's will probably push close to 125db at your seat without compression over this range), cleaner response outside of the pass band, lower distortion, etc. Using these dedicated mids has little to do with the fact they will play cleanly up to 6k. You could go with dual 6NDL38's which have more Xmax and can play lower, but also have lower sensitivity. If your budget was lower, this would be a good option, but at your budget, going with a higher sensitivity dedicated mid in a 3-way is beneficial. Using 2 of them side-by-side gives you the horizontal directivity benefit. The downside is the additional cost and complexity. IMO, it would be worth it in your case. In a home theater it would be questionably beneficial. As far as which midbass driver to use, it really depends on how much space you have. Ideally you would go with the largest diameter high power handling pro driver you can fit. It seems a 12" driver is your limit on width which is fine. I would look at the TD12S, since you will only use it from ~80-300hz. There are many many 12" pro drivers that can work well in this application. Using the W15Gti up to ~200-300hz is a possibility. I wouldn't go past that. You could definitely give it a shot or start with the W15GTI covering the bottom end by itself. It depends on where you are planning to place them. With a cross around 200-300hz, you won't want them too far from the mids. I do think it would be a better system with a separate midbass driver though covering about 80hz-300/400hz. The W15Gti can still cover up to around 120-150hz if they are kept close to the speakers in a flanking configuration. You would simply Eq to blend them in the over lap region. This can give you better multi-position bass response in the very tough 80-200hz range. You can experiment with "absorbed/killed OB" for the mids. I don't have much experience with this, but I would say it is way down the list of effectiveness if you are trying to achieve low distortion and low power compression. The benefit of using the dual 6" dedicated mids is large relative to what is potentially nothing more than a concept pushed by hifi snake oil salesman. Of course, it would be easy to try and experiment with and I don't see any downside to trying. The only ways I can see besting my proposal for your system either requires significantly more budget (swapping the SEOS15/DNA-360 for a TPL-150H adds about $500 per speaker) or significant difficulty (DIY Synergy clone or using a cone midhorn instead of dual 6" mids). Within your budget I really don't see anything doing a better job for your situation.
Thanks that all makes a lot of sense. My main plan is for the W15's to be under the tops, with the drivers just under where the LSR's are now (actually the whole thing taller than it is now so the tops can be angled over my head for the people behind me just a bit). It's very helpful in the studio to be able to see the subs in case of some errant ULF on a track that didn't get HPF'd. Also for the sake of HPF'ing a side (all out-of-phase signal L to R...mono-izing it) it's preferable to maintain stereo bass as far down as possible. If I need more subs or more broad band absorbers or Helmholtz resonators I'm going to tackle that as a separate step...but for now I get pretty decent bass response in the room even from just the LSR's (gotta be at least 1000lbs of 703 in here). If I were to up the budget for the TPL-150H's would it be possible to pair them with a pair of 8" mids that were adjacent horizontally with the tweeter above or below the pair? 13500/8= 1.6k and it looks like the TPL will play that low...for planer drivers is it only center of cone to edge of planer source? There seem to be more 8" mids that extend another octave lower than the 6's available like Beyma 8g40 or B&C 8 PE21. Have you compared SEOS to TPL-150H? The 150H has been on my radar but it is a little pricey...if it's worth it though I can make that happen, especially if that means 3 way is a possibility. It would be cheaper I think to add subs for the modal region (factoring in amp costs here) than to go 4-way along with everything else... I do hear you on the snake oil bit, the only reason I want to knock out a quick experiment with that is to see if I can make the boxes as shallow as possible, as this would leave me more leeway to optimize the toe in and down angle. And I already have MLV and 703 on hand. Thanks this is very very helpful-
If you want the mids to extend lower I'd probably go with B&C 6NDL38's (http://www.parts-express.com/pe/showdetl.cfm?partnumber=294-646) or 18Sound 6ND430's (http://www.usspeaker.com/eighteensound-6ND430-1.htm). I'd have to model them, but they should play down to ~120-150hz sealed and would work better with the W15's. You would give up some sensitivity and they might exhibit a tiny bit more compression, but it is likely undetectable. They do cost more. Going this route will push the budget down a little and give you room to upgrade if you ever feel the need. These would basically be Super Daniels moving up to a SEOS-15 and pro grade mid's. I've heard AMTs in commercial speakers and they are nice, but I haven't heard the TPL-150H specifically. It is a good possibility although it has one major issue besides price. It's vertical directivity collapses significantly above ~8khz due to its height. At your seating distance a 10deg window is pretty narrow. I've thought about trying to mitigate this by applying foam strips to effectively delay and attenuate the upper and lower portions of the driver like RAAL does but it is just too far down my project list. I would stick to adjacent 6" drivers because it minimizes the CTC distance between the SEOS and mids while also giving you more wiggle room on crossover range. Two 8s would probably start to narrow their directivity a little lower than I'd want in your case. Dual 6's are the sweet spot under a SEOS-15 or even a TPL-150H. The 6's I mentioned above are more midwoofers than midranges and can cover low enough to do 3-way with your W15GTis. I really think this will make for a very tough to be beat mid-field studio monitor setup. The weakest link should be the dynamic capability of the W15GTi's which should be easy to fix, if it ends up being an issue (I'm not suggesting it will be, just that it will run out of steam before the mids or SEOS. Definitely try the damped OB setup. There is no downside to it. I'm just averse to putting weight on such incremental and potentially meaningless "tweaks". Many times the differences can be explained due to other changes that occur rather than what the person wants to believe is occurring and thus the cause. IOW is it the back being 100% killed due to an open back or stuffed open back relative to a stuffed closed back? The stuffed closed back will also do a very effective job of absorbing these frequencies. I'd like to see the effect measured.
Great thanks- What about faital pro w6n8-120's? Higher xmax than the b&c mids with about the same efficiency...they model pretty much identically.
There are many 6" pro mids out there. I've only seen tests on some of the 18Sound and B&C drivers. I wouldn't be too worried about xmax since you will want to minimize this anyway. I would suggest putting them in a sealed box and highpassing so you get no more than 3-4mm of excursion at top volume levels. That FP driver might be good. It is up to you. The others have a flatter response. The main thing you are looking for is 2 6" pro drivers that can cover ~150hz - 1200hz and handle enough power to get you the dynamics you need. Are you porting your W15GTis?
So a pair of 6MD38's would be comfortable down to 150? For the w15gti's I was originally thinking sealed but if they are going to match up with a true mid like the 6md38's it would probably be better to port them to lower xmax and IMD right?
Loading the 6MD38's in winisd pro and from the model in there it looks like if there are 4 drivers it would substantially lower the xmax requirements. Would a 2.5 way XO work for something like this, having 2 of them run up to the seos and 2 more for a little help at the lower end? Or at that point it would probably just make more sense to add a high sensitivity 15" instead of the additional 6md38's.
I wouldn't use the 6MD38s that low. I'd use the 6NDL38s that low. The 6MD38 is best kept above about 200-250hz where I'm not certain how well the W15GTi will do. I'm more confident in the 6NDL38s mating to the W15GTi. As far as vented or sealed with the W15GTi that will depend on your requirements. If you don't need content below ~20hz vented might be better with just two W15GTi's to enable you to reach the levels you need uncompressed. The downside to ported IMO is port resonance which might be an issue if you are using the W15's up to 150hz. I generally prefer sealed but only if you have enough headroom in displacement. Are you placing the W15s in corners? It would probably be best to measure them to see if they will do what you need. I'm guessing that you will need significant boundary reinforcement for a pair of sealed W15's to reach 120db at 20hz.
That makes sense- Also looking at TD6M's if they are available, whats the availability of the SEOS-15 or the resin one? That's a group buy? I got my 4bst back and it sounds incredible with the LSR's so I'm thinking if it takes a long time to get the best parts that might be worth the wait for the 15 resin and maybe the TD6m's. For levels I figure 90dB @ the listening position with material that is ~30dB average under peak would be more than enough. So 120dB but that's not counting that the components have some ability beyond RMS power ratings. I'm modeling the w15's at 116dB for the pair @20hz sealed and that really should do it, especially because yes they will be in corners, either wall/wall or floor/wall/wall. In the pic the woofer is on top but I can turn them over also or lay them sideways with the boxes going towards the middle. Generally most music is getting HPF'd at 30hz or higher and knowing the limitations of the system around there I can manage that. Or add a couple more subs for a little more overhead/smoothness. Almost done with the modeling, now it's time to export to acad, get my dad's buddy to double check that it will be good to go and then it's off to the CNC shop. These suckers are going to be heavy (drivers are 40lbs each)...
You would have to ask Erich about SEOS-15 availability. I would definitely do resin over FG for the cost savings. There no loss of performance. The TD6M is a possibility. I shied away from mentioning it because I haven't seen it in use much. I did recall seeing someone having a slight response issue a while back. I don't know if that was an outlier or not. You might need to ask AE about that issue. If that problem has been resolved, it would definitely be a good option. Your W15's should get you in the 120db ballpark. Models only mean so much though when it comes to truly clean output. I think you will be fine though with the corner placement. About the only way to get less compression in a mid-field monitor like this would be a Synergy horn because you could use 6-8 equivalent mids and they would be horn loaded. 120db uncompressed is not an easy target. I guess it depends on how uncompressed you want. I'd like to see commercial monitors that can realistically best this. I'm not talking about some bogus spec sheet. Keep us posted.