Hi, I've been reading the "dome midrange thread" and keep getting that itch to try something new.
My current speakers are an active 3 way that I've made myself using using drivers that have been recommended from this awesome forum. They consist of a T25b tweeter(5in wave guide), NE149W-08 mid and an sb34nrxl75-8 woofer in a 65L ported box tuned at 29hz, Everything has been impedance checked for resonances and standing waves and rectified where needed.
I made these speakers modular so I could try different things.
They currently sound amazing and I'm blown away every time I turn them on, they have a large 3d/deep sound stage with great detail and an amazing easy listing experience but you know how it goes with us type of people!
These are run from a Minidsp flex ht, 6 channel home assembled Icepower amp(1200as2/400A2/125asx2 new conductor version for the 125asx2). Crossovers are currently 250hz/2700hz all LR2. I have a good bit of experience with DSP from my car audio setup also with a mindsp 8x12dl.
I have a spare set of NE149W-08 drivers and can sort out another two channels of amp. What i'm thinking is to make another box section that sits between the current woofer box and the midrange pod. Then put two NE149W's side by side in that box(that would be the same style as the woofer box) and then a scan speak D7608 3in dome in the mid pod(with the correct enclosure size of it's own) or make a new mid pod that gets the ctc spacing a little closer.
I did also think about using one NE180W for the midbass but if the two 149's per side would work then that would be better as I already have them.
Then I would aim for crossovers somewhere around 150-200ish/6-700/2700 or whatever works best.
Trying to manage tweeter height would also be of concern.
My current desire is lots of detail and good dynamics. I'm also not really wanting to spend Bliesma M74 type money on this experiment.
Any thoughts or problems you can see?
Thanks.
My current speakers are an active 3 way that I've made myself using using drivers that have been recommended from this awesome forum. They consist of a T25b tweeter(5in wave guide), NE149W-08 mid and an sb34nrxl75-8 woofer in a 65L ported box tuned at 29hz, Everything has been impedance checked for resonances and standing waves and rectified where needed.
I made these speakers modular so I could try different things.
They currently sound amazing and I'm blown away every time I turn them on, they have a large 3d/deep sound stage with great detail and an amazing easy listing experience but you know how it goes with us type of people!
These are run from a Minidsp flex ht, 6 channel home assembled Icepower amp(1200as2/400A2/125asx2 new conductor version for the 125asx2). Crossovers are currently 250hz/2700hz all LR2. I have a good bit of experience with DSP from my car audio setup also with a mindsp 8x12dl.
I have a spare set of NE149W-08 drivers and can sort out another two channels of amp. What i'm thinking is to make another box section that sits between the current woofer box and the midrange pod. Then put two NE149W's side by side in that box(that would be the same style as the woofer box) and then a scan speak D7608 3in dome in the mid pod(with the correct enclosure size of it's own) or make a new mid pod that gets the ctc spacing a little closer.
I did also think about using one NE180W for the midbass but if the two 149's per side would work then that would be better as I already have them.
Then I would aim for crossovers somewhere around 150-200ish/6-700/2700 or whatever works best.
Trying to manage tweeter height would also be of concern.
My current desire is lots of detail and good dynamics. I'm also not really wanting to spend Bliesma M74 type money on this experiment.
Any thoughts or problems you can see?
Thanks.
Linkwitz says don't use ported bass (Have you tried yours sealed?), and don't trap midrange in a box. So go OB on top and sealed bass on bottom. Active 4-way of course!
(a la SL's LX521?)
https://www.linkwitzlab.com/LX521/LX521_4.htm
(a la SL's LX521?)
https://www.linkwitzlab.com/LX521/LX521_4.htm
WOW, well done. Hurry to know more !
Where did you source the magnificent mid enclosure please ?
Bravo !
Where did you source the magnificent mid enclosure please ?
Bravo !
Great looking speaker. MTM doesn't seem to work well horizontally. We type it that way I know but really it should look like this
M
T
M
M
T
M
If you are DSP active filtering I would try a high pass at 200 electrical and low pass around 1500/2000 electrical. Which should give circa according the slope something acoustic 250/300 Hz cut off and 2000/2500 He cut off.
The NE149W can be go higher but the tweeter is excellent and there is a little upper resonance in the Peereless that is best to avoid in the upper 5/6 K hz.
But hard to know w/o measurement. Drivers are no slouch, good choice, near a project I have (different tweeter only because the too much expensive T25B for I)
Edit.... But I see you have the Flex 8. Take a measurement with a mic at sweet spot and also at 50 cm from the NE149W to see ho is the 800 hz /1500 hz which is the only weak point of the NE149W : sound better when flated. Look also if the 5/6K resonance is there. We don't know how consistant is the datasheet. You eventually can try a 3k acoustical too.
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Btw I also took 4 units of the NE149W, but only if spl is needed for the baffle step in the area of cut offs I talked above for a MMT conf instead of a MTM. If you want to test a MTM though, plan a cut off around 1500 to 1800 hz acoustical.
Feasible for spl in home environment with this driver in 50 to 55L sealed with a bass boost (Linkwitz transform).
Hi, do you have any related reading/links about this, from Linkwitz's website or elsewhere? I couldn't find it in the link you provided, and a google search unfortunately didn't help either.
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I've tried them sealed but they lack the meat down low. The music looses it's presence so to speak. It becomes boring.
My lounge is not suitable for open baffle.
My idea was midbass side by side, I would have thought the 7-800hz crossover between M to MB wouldn't be to bad with the two 5in below the mid dome and close together.
T
M
MB-MB
I designed them in fusion 360, 3d printed them in petg then lined the inside with car bog filled with lead.
For your other fr question. These ne149w-08's I have don't have anything odd going on around 1500-2000hz. They are just as flat as some 12mu's I've tested in the same pods. They all have a slight raise around 2k.
I've tuned these as i do with my car audio sort of, bass is tuned at the listing position but tweeter and mid is eq'ed at 1m and then a check is to for how they all sum together.
All with pink noise and each driver is tuned to match the electrical slope of the crossover.
I've done many different methods of eq and no eq but this is the best.
I'd use a midTL. Sealed everywhere else.
A 4-way should really be 3-way mains and 2 (or better 4) subs (push-push [and sealed w DSP or at least PEQ] has huge advantages). I personally wouldn’t bother with a tweeter but use a good midTweeter instead. (good recent example) Then after you add the subs it s a 3-way.
WRT to the image in post 1, nice mid-encloure, tweeter should be as close to the mid as possible, even tweaking the tweeter bezel to et things closer. Ifyou are going active a coax (ideally with DSP for delaying the tweeter outpout)
dave
Th eideal distance is ≤ the quarter wavelenght of the centre-to-centre between the drivers.
dave
The first photo isn't the best. I've printed the waveguide with an exact negative shape of the mid pod to get the ctc as close as I can. There is also a 60mm diameter channel molded into the top of the pod to help get things closer.
There's a few things I would have done a little differently if I was to do it again.
It is. Waveguides (and horns) have the dilemma/compromise of lowering the frequency it can go, but making it a bigger size.
The joys of loudspeaker design — compromises galore…
dave
The joys of loudspeaker design — compromises galore…
dave