10” pro drivers makes for perfect high spl mids, they meet the woofers/subs well, and still can go up to 1400-1500 without beaming (with the right setup)
my last build was two way with single 10, next build is mtm with 10’s over 15” bass modules…..I listen @ 9’ and have no issues.
Go big you’ll not regret it.
my last build was two way with single 10, next build is mtm with 10’s over 15” bass modules…..I listen @ 9’ and have no issues.
Go big you’ll not regret it.
At the volumes this chap is actually going to be listening to music it's completely irrelevant. He doesn't want to listen at obscene levels he just wants the system to be capable of it for effortless sound at the levels he does listen at. Use a ~97dB midrange, like the NERO-6MRN150D and I don't think power compression is ever going to be an issue, nor would the lack of dynamics.
Not once have I ever seen flaxxer appear remotely interested in going with a tweeter that can cross over as low as required to get the dispersion of such a design under control. He seems to show a liking for big ribbons which isn't going to work well with an idea of an 8" MTM.
I didn't directly mention the things you're talking about because I thought it was obvious what technical challenges need to be overcome for such a design. And with the inclination flaxxer has towards certain tweeters they would not be handled correctly.
Well unless you're going to use a very low crossover point you're going to get worse vertical off axis performance than you would get with a smaller midrange, or by using a simple TM. Why complicate the speaker and make other things worse/harder when there's simply no need?
A lot of this thread seems like it's trying to create solutions to problems that don't exist. We are essentially designing a system for what amounts to a small room due to the listening distance. Wanting to build a high sensitivity system, for such an application, is absolutely fine but people seem to be forgetting that flaxxer doesn't want to listen that loud. The 120dB figure is something he arbitrarily decided because he figured it would be good enough. We need some common sense people.
8" MTM with pro sound midrange drivers and 100+dB sensitivity? What on earth would you want to do this for with the intended application? It's completely overkill.
Flaxxer has a pair of 3012LF drivers already and seems to like them. After bafflestep compensation he's going to be looking at around ~91dB net speaker sensitivity depending on how much compensation he needs. Now personally I think if he used 1x 3012LF (Eminence), 1x 6ND430-8ohm (18Sound) and 1x GRT-145W-8 (Viawave) crossed over at 300Hz and 2kHz it would be actually be enough. But that's playing it a little too safe so...
The other option would be
2x 3012LF (Eminence)
1x MCF200ND (Beyma) or 1x NERO-6MRN150D(SB Audience)
1x GRT-145W-4 (Viawave)
Cross at 350Hz and 2kHz for a 96-97dB speaker...
This would completely blow his socks off. Why on earth would you need more speaker than this for his application? It'll do ~120dB with 100 watts if needed and send you to the ENT clinic for hearing aids with extended listening with just 1 watt.
This is the most important thing here which is why I've said go with the OSMC before. They'll be the same end sensitivity as a design with his 3012LFs anyway.
These are the type of comments of a speculator, long winded and confident, as well, not holding weight...
The larger woofer will play lower distortion, lower bass extension. It is worth it for the OP to choose a tweeter that compliments the larger woofer than to choose an AMT and reduce midwoofer size. If you go to the beginning of my thread on 2 ways youll see I started my journey stating 120db as a max spl spec and I was favoring AMT woofers...thankfully the genius members of the board saved me from myself...guess what else was a main criteria for my intended build? Max dynamic contrast...I spent the better part of year discerning what even meant...
My system is designed for 1 meter, and it might be (lol) called over kill to some...If the distortion gets too low do you think it might cause a rift in time space lol! If the polar is big enough...it flys...vertical off axis performance (via ctc) is compromised in nearly everyone horn or large waveguide design...no ones complaining...because horizontal dispersion is much more critical.
8ft is far to me, I design systems for 1 meter. An mtmw with 8" mids will be fine at 8ft...or 3ft as long as its designed right...and used right...
But more importantly, you don't fully understand the prowess of large diameter mid woofers, and it shows.
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Not really, 5th_element. Because I plan on going active. I really do want high efficiency. This seems easier than finding several 105db efficiency drivers to passive xover down to 96db level.
Monkey coffins, and the nice JBLs are over $5000. Over my budget. There is really only one other bass driver I would consider. The Faital 15PR400.
But why, when I already have amazing sounding drivers for this?
Addressing the dual woofers ... Not enough room. They would be 6cu ft for the bass drivers, to do it right. Mine are in 3cu ft, ported. Tuned to 40 hz. With a bit of EQ they can play to 34hz -3db, with a very steep subsonic filter at 32hz. They are amazing like this. But this is their idea size enclosure to do this with, and two would be HUGE.
Solving this next proposal ... I don't see the need to go MTM with an 8" or 10" Faital mid of 98db efficiency. I'm already limited to 95.5db efficiency of the woofer, unless I changed to the 15" Faital woofers. My question is, can they do what the 3012LF can in a similar sized enclosure?
Again, I am going active with these. It just makes sense.
I can learn to design a passive xover with a two way bookshelf. I already have one in mind. It is 2.6cu ft. I own them. But know the xovers could be much better. So a later project.
Monkey coffins, and the nice JBLs are over $5000. Over my budget. There is really only one other bass driver I would consider. The Faital 15PR400.
But why, when I already have amazing sounding drivers for this?
Addressing the dual woofers ... Not enough room. They would be 6cu ft for the bass drivers, to do it right. Mine are in 3cu ft, ported. Tuned to 40 hz. With a bit of EQ they can play to 34hz -3db, with a very steep subsonic filter at 32hz. They are amazing like this. But this is their idea size enclosure to do this with, and two would be HUGE.
Solving this next proposal ... I don't see the need to go MTM with an 8" or 10" Faital mid of 98db efficiency. I'm already limited to 95.5db efficiency of the woofer, unless I changed to the 15" Faital woofers. My question is, can they do what the 3012LF can in a similar sized enclosure?
Again, I am going active with these. It just makes sense.
I can learn to design a passive xover with a two way bookshelf. I already have one in mind. It is 2.6cu ft. I own them. But know the xovers could be much better. So a later project.
One approach you may not be aware of Flaxxer...pick a favorable manufactured design...clone it to your liking...5000 jbls you say you like...it will cost you much less to build the same type thing yourself
Ps- with active xo, you don't need to match sensitivity so closely as you would with passive...unless you are looking at a 110db horn combo...the sonic quality due to such low distortion via efficiency...is hard to compliment with lower efficiency woofers.
Ps- with active xo, you don't need to match sensitivity so closely as you would with passive...unless you are looking at a 110db horn combo...the sonic quality due to such low distortion via efficiency...is hard to compliment with lower efficiency woofers.
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I'd be surprised to see this a problem in practice. (It's very close to the M/M spacing.)camplo said:
I might be able to illustrate some of the concerns with typical MTMs using this vertical plot of a 10" MTM with an asymmetrical waveguide. The ~500Hz-1kHz region appears to narrow further than it should, apparently due to the wide mid driver spacing. The next octave up narrows further, apparently due to a crossover which is not tailored to take proper advantage of the configuration. The next octave goes wide, apparently because the selected waveguide is much too short in the vertical dimension in an attempt to try and get the mids closer together. Finally after 5kHz the waveguide takes on its final form, demonstrating both where it should have been expected to cross, and where the directivity should have gradually moved toward.
Attachments
Everyone has to draw a line somewhere with regards to just how overkill they want to be. Given that a system of 96-97dB sensitivity, like I described above, would cause hearing loss when used at 1 watt, for any decent length of time, I would call the power compression, of said system, to be negligible. Sure turn it up to 120dB, with 100 watts, and power compression is going to be much more of a concern. Your ears, however, are going to be in so much distress at that point that a dB of power compression is the least of your concerns.
You won't get any disagreement on this. If I thought that flaxxer was going to choose a 10" mid, and then pair it with a 10" waveguide (and suitable compression driver), and cross the two for a directivity match things would be great. This isn't what I've seen him come close to contemplating though.
I see all dispersion angles as important. I strive for the best in the horizontal and vertical plains. If the added SPL capability of a bigger, and wider spaced, set of drivers is not required then it's a wasted compromise. You're going to have spent more money, built a bigger and more obtrusive speaker, and ended up with poorer vertical off axis performance, for what? Performance in an area you'll never, or very rarely, take advantage of.
Well if by used right you mean keeping your ears locked at a particularly height all the time, sure. I do not like this as a compromise. Yes I'll accept it if it's necessary but in this case I do not see it as being necessary.
Well I mean my main speakers use a pair of 10" Deltalites for the bass/lower midrange and then the B&W FST as a midrange driver. All of this is pushing 95-100dB sensitivity between 100Hz and 2.5kHz. It has very low levels of distortion over all volumes I care to listen at and ridiculously low distortion at my typical listening levels. The FST is used coaxially (tweeter in its voice coil) and displays excellent off axis performance across any angle you want to measure/listen at. What exactly am I missing by not using a bigger midrange? Because I fail to see it.
Sorry, I am late to this thread, but...
Nope, a pair of Monkey Coffins is about $3500. I believe they might be a perfect match. You might also want to take a look at the tower version of the Monkey Coffin.
Nope, a pair of Monkey Coffins is about $3500. I believe they might be a perfect match. You might also want to take a look at the tower version of the Monkey Coffin.
Okay well the goal posts have now moved since the start
It doesn't really matter actually. Padding 105dB drivers down to match a 96dB bass driver isn't that much of a bad thing. The speakers power compression, for the 105dB drivers, will be exactly the same for the active and passive versions as the drivers will only be seeing the amount of power required to play at a certain level. It's just with the passive design some of this power will be lost as heat in resistors. So okay the amplifier will have to work a bit harder too but as long as it isn't clipping, and it's well designed, that's not really a problem.
In fact if you're using 105dB midrange and tweeters the noise in the amplifiers/preamplifiers/CD players/DACs/whatever has to be extremely low if you don't want to hear hiss. If you've had to lower the level of the 105dB drivers down to 96dB, with passive resistors, any noise in the rest of the system becomes a lot less of an issue.
I thought someone already priced up the Monkey coffins elsewhere in the thread and they were within budget?
I guess the biggest concern is because you don't know how to use them.
Okay but you realise that when used as such the end, net, sensitivity of a finished loudspeaker with those bass drivers will only be around 91dB. As long as you are happy with this then that is fine.
This is not correct. You will lose 4-6dB of sensitivity because of baffle step. The end result will be a speaker much less than 95.5dB. Why do you think the Monkey coffins are actually 90dB when they use a bass driver listed as being 97dB by the manufacturer?
You seem to have missed the post where I mentioned that designing an optimum crossover for an active, or passive, system are the same thing. You need to be able to make the same measurements for each and know what to do with these measurements for either (passive or active) of them to work properly. It's easier to implement the active crossover, because they are more flexible, but they are not, inherently, easier to design properly.
At the very least, read the stickies to gain an understanding of what's involved.
So you want to design your own speaker from scratch!
I personally would never try to design a crossover without measurements, but this is still well worth a read.
Introduction to designing crossovers without measurement
I don't quite agree. An active filter will (usually) see a load with a high and constant impedance, which does not need any measurement. Passive filters will see the variable impedance of the drivers, which needs to be measured in order to include this in the filter design.
That said, impedance measurements are easy to do, so the additional work for designing passive filters is not much.
+1
Especially a 3-way.
If you don't have any experience in designing crossovers, taking measurements, interpreting driver parameters and understanding the different measurements,
I strongly suggest to stick to a proven design like the OSMC, the semi-active Loudspeaker III, Calpamos, ...
True. The OSMC uses a passive filter, but an active filter is not impossible. The OSMC filters were designed using a digital signal processing (DSP) unit. While the final (passive) filter design is passive and has slightly different transfer functions than the DSP prototype, it would be possible to tweak the DSP version to match the transfer functions of the final passive filter. That said, I preferred the passive filter over the DSP prototype in listening tests.
In terms of parts costs, a DSP might be cheaper than a good quality passive filter. However, going with active filters requires six amplifier channels, whereas a passive filter require only two.
mbrennwa, how did you choose the SS tweeter ? Not often seen this ref !
Some cheap ribbons or AMT were out of question ? <or did they simply not match the mid dome ?
The Faital 12P320 is said to be more enjoyable than the 15PR I have read
Long time ago I planned to make something with this Faital 12 but in sealed for a better low end group delay but maybe a wrong choice indeed ! Vented is maybe better with it !
Looks cool, will make it if I had the budget. Thanks for sharing mbrennwa !
Some cheap ribbons or AMT were out of question ? <or did they simply not match the mid dome ?
The Faital 12P320 is said to be more enjoyable than the 15PR I have read
Long time ago I planned to make something with this Faital 12 but in sealed for a better low end group delay but maybe a wrong choice indeed ! Vented is maybe better with it !
Looks cool, will make it if I had the budget. Thanks for sharing mbrennwa !
The details are in the OSMC thread. Basically, it was about matching the dispersion of the midrange driver using a waveguide. Since ring-radiator tweeters help to avoid the (sometimes large) SPL irregularities with waveguides at high frequencies, we wanted a ring radiator rather than the typical dome tweeter.