Hello everyone! Interesting suggestions! This community is just chefs kiss
According to you the 2 way could work if I use a waveguide above and a large driver below (10/12/15") but I feel like can't go that big. I think I'm looking to build a medium sized bookshelf speaker at most.
I think I'll go with the 1 - 4 - 7 I suppose the only concern would be integrating the 7 and the sub. I guess it should be fine for now.
According to you the 2 way could work if I use a waveguide above and a large driver below (10/12/15") but I feel like can't go that big. I think I'm looking to build a medium sized bookshelf speaker at most.
I think I'll go with the 1 - 4 - 7 I suppose the only concern would be integrating the 7 and the sub. I guess it should be fine for now.
How about a 1+3+5.25 3-way? 0.23ft^3 PR box... SB 5*8" PR on the back for F3/10 of 52/38Hz anechoic. In room about 3' from walls these things can DIG.
Oh- and the xover is fairly simple for a 3-way with mostly 12dB electrical slopes (except the tweeter), and all drivers have shorting rings or caps.
It's apparent that they do here:
And measured gated response, 1/12 smoothed:
I finished these up about a week ago soundwise, and they are impressive for the outlay. Peerless P830945/Dayton PC83-4/Dayton DSN25F-4/SB SB15SFCR-00 PR.
Smaller 3-ways can do a lot of things very well!
Wolf
Oh- and the xover is fairly simple for a 3-way with mostly 12dB electrical slopes (except the tweeter), and all drivers have shorting rings or caps.
It's apparent that they do here:
And measured gated response, 1/12 smoothed:
I finished these up about a week ago soundwise, and they are impressive for the outlay. Peerless P830945/Dayton PC83-4/Dayton DSN25F-4/SB SB15SFCR-00 PR.
Smaller 3-ways can do a lot of things very well!
Wolf
That's pretty much what I just used, though I didn't use a waveguide and I used the 15NBAC.
I'm not disappointed, the 26W/8534 really is a nice woofer (but I'm probably going to add a subwoofer later for movies).
Indeed! 'Preaching to the choir'! 😉
At 7-8 ft away and ideally needing the first reflections at/behind the listener's ears, recommend doing a floor plan to scale to find the angles before going any further and preferably using the largest practical of each range.
Yeah, preaching everyday, leaving breadcrumbs for future, for the explorer 😀
While any speaker outputs sound in any room it is well worth it to try optimize the situation as they both work together as a system, it is sound in a room the hearing system deciphers, not speaker driver count or size or brand. Thinking the speaker and room as system arrives easily to at least three way loudspeaker system though. Size and cost are important in many situations of course, and it all has to be fun! So what ever rocks the boat. There is always possibility to do another project afterwards exploring bit deeper if sound is not good enough 😀
While any speaker outputs sound in any room it is well worth it to try optimize the situation as they both work together as a system, it is sound in a room the hearing system deciphers, not speaker driver count or size or brand. Thinking the speaker and room as system arrives easily to at least three way loudspeaker system though. Size and cost are important in many situations of course, and it all has to be fun! So what ever rocks the boat. There is always possibility to do another project afterwards exploring bit deeper if sound is not good enough 😀
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^what I was trying to say here is that thinking the actual needs like directivity and how the loudspeaker system relates to the room and listening position, what kind of SPL and bandwidth expectations there is for the system pretty much dictate how many ways and what size drivers are required to make it.
If it is strict question 2 or 3 ways without thinking what is actually needed for application the answer is 3 ways as it allows more separation of concern, more SPL and bandwidth, different wavelength have different requirements for nice sound in a room. Andy and others opened some of it up already. But, this leaves a lot questions hanging in air, the whole system is yet to be defined. Size and budget could constrain to make a small system in the end and none of this deep thinkin stuff matters too much. Big life like sound requires big speakers, enough SPL capability for dynamics and bandwidth for highest highs and lowest lows and careful management of it all so that the room is taken account for best delivery. Not everyone needs or wants this, or the situation might not allow. Anyway, most important thing is to have fun with the hobby 🙂
If it is strict question 2 or 3 ways without thinking what is actually needed for application the answer is 3 ways as it allows more separation of concern, more SPL and bandwidth, different wavelength have different requirements for nice sound in a room. Andy and others opened some of it up already. But, this leaves a lot questions hanging in air, the whole system is yet to be defined. Size and budget could constrain to make a small system in the end and none of this deep thinkin stuff matters too much. Big life like sound requires big speakers, enough SPL capability for dynamics and bandwidth for highest highs and lowest lows and careful management of it all so that the room is taken account for best delivery. Not everyone needs or wants this, or the situation might not allow. Anyway, most important thing is to have fun with the hobby 🙂
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Actually, based on reverse engineering the 8" 3 way W.E. 755 that to many is still the best overall performing wide range driver only gets the majority of the BW, so a (sub) woofer and super tweeter is required for full 20-20 kHz, ergo if I were to 'follow in their footsteps' it would have to be a 5 way though it would have at least a co-ax and preferably a tri-ax as they did assuming a good enough one was readily available.
Yep, subs to handle the room size wavelength and small tweeter to handle the thumb size wavelength. Now we are in control of both extremes but these two don't meet each other without problems so at least one mid driver is required for the bulk, the meat, where the important message is, the vocal. If bandwidth is relaxed then perhaps all that is needed is the mid, many people seem to be perfectly fine with single fullrange driver. Never compromise the mid. Philosophy all the way 😀
Before buying anything I would suggest working through the implications of baffle step correction and how to handle it. This may push you towards a configuration with a more balanced woofer area. If you are set on a 7" midwoofer for reasons of size a 3" midrange or even a 2" with 3/4" tweeter may be preferable. An alternative might be to design for on-wall location only and remove the need for baffle step correction.
Once again many many thanks to everyone for insightful discussion!
@Ugg10 That looks slick! It ends up being a large modular tower speaker but still it's more portable that an actual tower! This gives me a solution to my problem with heavy difficult to move around speakers: modular design!
@andy19191 What if I go with a modular design like the SBA 741 by Mr Gravesen or an even more modular illuminator 5, would baffle step be less of a concern since every driver has their own little housing and the baffle for each driver is not that large.
As suggested by Ugg10 I could add a 10" bass module later on (resources permitting) if I go with separate housings for each driver. It would end up being a 4 way eventually but one that is far more portable. As you suggested 3/4" tweeter, 3" mid-range, 7" midwoofer, and eventually a 10" woofer or some other combination of driver sizes.
@Ugg10 That looks slick! It ends up being a large modular tower speaker but still it's more portable that an actual tower! This gives me a solution to my problem with heavy difficult to move around speakers: modular design!
@andy19191 What if I go with a modular design like the SBA 741 by Mr Gravesen or an even more modular illuminator 5, would baffle step be less of a concern since every driver has their own little housing and the baffle for each driver is not that large.
As suggested by Ugg10 I could add a 10" bass module later on (resources permitting) if I go with separate housings for each driver. It would end up being a 4 way eventually but one that is far more portable. As you suggested 3/4" tweeter, 3" mid-range, 7" midwoofer, and eventually a 10" woofer or some other combination of driver sizes.
@DIYhopeful if you look on the “way back machine“ internet archive the Troels SBA741 upper module was originally published with all of the crossover values so you could source all of the parts yourself rather than through Jantzen.
Also if you like the Kairos 6+1 solution there are plans out there for a sub module with passive crossover schemes.
Also if you like the Kairos 6+1 solution there are plans out there for a sub module with passive crossover schemes.
Baffle step correction means bass leaks out the back & sides of the cabinet when the speaker is mounted on poles at the front of a stage, or in the middle of a room. Means speaker has to produce more bass to be flat response out in the open than the driver tests in a big stiff wall shown on datasheets. Crossover tweaks & cabinet tuning can do baffle step correction. Signal boost of crossover or DSP puts huge watt load at low frequencies on the bass driver. Bass reflex cabinet tuning low causes driver to hit xmax at low frequencies, maybe tearing the suspension if wattage is too high.
Answer for most home users, place the speaker against one stiff wall to reflect bass out to your ears. Ear level above hard floor helps too. I measured my SP2(2004) speaker against a 1" thick plaster wall, 73 cm above wood floor on a cabinet. Mike was 6' from speaker at ear level. Datasheet response of speaker is level at 60 hz, 15 db down at 40 hz, 25 db down @ 30. My measurement 2 m away from speaker against the wall, 8 db drop from 60 to 40, 10 db down @ 30. So I don't need a sub.
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No. Low frequency sound will radiate rearwards with the baffle size/width only influencing the frequency range over which it happens. How to handle this well with baffle geometry, crossover frequencies, driver efficiencies,... separates good designs from the less good.
If separate cabinets are OK for you in terms of packaging then they can be both more flexible and lead to quieter cabinets because the requirements for a good quality sub or woofer cabinet is different to that for a good quality mid+tweeter cabinet.
A 10" is a good size for a 3 way crossed at 300-500 Hz or so. Plus something like a 3-5" midrange and 1" tweeter. Splitting into 2 cabinets has some performance advantages but running the midrange+tweeter down to 80 Hz to cross to a sub isn't reasonable.
A 6.5" upper midrange in a 4 way would normally cross at 150 Hz or so but not usually to something as small as a single 10". If you wanted to cross at 80 Hz as an interim measure it would influence the driver parameters away from optimum for a 4 way but likely not unduly. I would plan on something bigger than 10" though for a future woofer module.
Given you have an existing sub, 1) a 2 way with a 6.5" midwoofer to get going makes sense, 2) a 3 way with an 8-10" woofer, 3-4" midrange and 1" tweeter would offer more performance for more effort, cost and size 3) a 2 x 8-10" woofers in one cabinet with a 4-5" midrange + 1" tweeter in another is approaching the size there is little to be gained for typical home use in going larger. More subs would help though. A well designed 4 way will be at best a small improvement on a well designed 3 way. For a first design a 4 way may not be the wisest place to start but DIY is about having fun.
A big system (2x10+4+1) seems overkill to me if you don’t need more than 95dB. Furthermore, such a big mains system requires really big subs to keep up with them. Really, a 6”-1” or maybe a 3 way with 6 to 7” bass is enough.
90-95dB@ 2.5m should be ok even with a woofer like sb15mfc/nbac, especially if crossed at 110hz Lr4. Even if it wouldnt excel in recordings with drums, probably
But a 6.5" or two 5" woofers would be a safer bet, wrt headroom/distorsion. Not nearly as fun as a bigger system though.
But i would say that even just one 18" Ultimax is quite a big bass system on its own and wouldnt be much of a weak spot in terms of spl for the bigger mains system you mentioned
Setting aside questions of what 95 dB means. If the OP listens at standard levels (i.e. cinema levels) and compares a speaker with a 6.5" midwoofer and a speaker with 2 x 10" woofers will the former sound just as "dynamic" as the latter? If not, how large do the woofers need to be to sound clean under these conditions? Note this is nothing to do with sounding loud enough which small speakers can achieve in small rooms. It is to do with sounding clean or "dynamic".
2x10” don’t fit the bill. And while you could argue that a 6” might be somewhat small (in 2500 cu ft, really?) anything with Vd above some 150 cubic cm seems overkill to me.
Can you simply find out for yourself? For example, could you buy or borrow something like these and give them a trial?
http://noaudiophile.com/JBL_LSR305/
Note that this chap also reviewed the larger version, and thought they sounded just OK on their own, but great with a sub.
Hmm, assuming the sub's XO is 80 Hz, the pioneers determined an 8" was large enough for high speech intelligibility, choir music, small band, so factor in some decent Xmax for higher peak SPL = ~150 cm^3, so +1. 😉
Mid/tweeter XO point would be around whatever the VC's diameter is, i.e. if 2" = ~13543/pi/2 = 2155 Hz.