I have the 7MS with an 8 inch Monacor in a WAW. I am currently listening with Xover around 450Hz and 12dB 2nd order passive. I have tried 1st order 350Hz passive but it didn't quite blend in. As I have a large listening space and like to play loud sometimes I felt the cone excursion of the 7MS was a bit too high. 2nd order at the slightly higher Xover is working well for now. I can't say I've noticed any downside from going from 1st to 2nd order slopes.
You could just build a simple box to try out the Alpair in your situation first. With the built in baffle step response and being close to a wall and a close listening position you may find it has too much upper bass. But it will give you an idea of what the next step is. If you built a bass reflex box you could then convert to sealed by stuffing the port if need be.
I think for moderate close up listening full range is the way to go with a sub as back up.
I think for moderate close up listening full range is the way to go with a sub as back up.
Hi Stal, thanks for your input. Out of curiosity, roughly what is your listening room and distance?
I plan on listening anywhere from 1-3m. It just depends where the speakers go and if I move house. In the nearest setup, the speakers will be against the wall (perhaps not necessarily wall mounted).
I am considering trying a small foamcore box for the alpair and seeing how it sounds and measures. If it's not so bad then I might be able to fix it with some small EQ, or perhaps crossing it a little higher might help.
Are your speakers sealed or ported?
I do have a sub and haven't tested the alpairs nearfield with it. I think it won't be enough unless I exclusively listen at about 1m.
I plan on listening anywhere from 1-3m. It just depends where the speakers go and if I move house. In the nearest setup, the speakers will be against the wall (perhaps not necessarily wall mounted).
I am considering trying a small foamcore box for the alpair and seeing how it sounds and measures. If it's not so bad then I might be able to fix it with some small EQ, or perhaps crossing it a little higher might help.
Are your speakers sealed or ported?
I do have a sub and haven't tested the alpairs nearfield with it. I think it won't be enough unless I exclusively listen at about 1m.
My room is an extension at the back of our house, open plan to kitchen and dining area. About 7.4m by 7m but L shaped not square. Seated listening distance is about 2.5m and standing (while cooking) about 5.5m. The fronts of the speakers are about 0.8m from the front wall.
Here's a pic with Pluvia 7s but now I have the 7MS.
The woofer is in a 46 litre bass reflex. The Alpair is in a short tapered stuffed transmission line (similar to what Dave, Planet10 uses in some of his designs). The idea is to reduce the amplitude of the impedance peak that allows easier passive crossover design.
Here's a pic with Pluvia 7s but now I have the 7MS.
The woofer is in a 46 litre bass reflex. The Alpair is in a short tapered stuffed transmission line (similar to what Dave, Planet10 uses in some of his designs). The idea is to reduce the amplitude of the impedance peak that allows easier passive crossover design.
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I see, that is quite large then. Larger than any of my rooms anyway.
I was considering also doing a tapered enclosure for the 7ms but with the shallow design I'm not really sure how to go about it. I am trying to think of the best way to stop reflections in the enclosure. I'm also not sure if it being sealed can affect the sound in a negative way.
Just out of curiosity, how do you find the pluvia 7 compared to the 7ms, now that you have had some time with them? I recall seeing you post about installing the 7ms a while ago.
I was considering also doing a tapered enclosure for the 7ms but with the shallow design I'm not really sure how to go about it. I am trying to think of the best way to stop reflections in the enclosure. I'm also not sure if it being sealed can affect the sound in a negative way.
Just out of curiosity, how do you find the pluvia 7 compared to the 7ms, now that you have had some time with them? I recall seeing you post about installing the 7ms a while ago.
The 7MS are better. With the Pluvias I used a notch filter on the higher freqs as on axis it was too hot for my liking. The 7MS are more detailed and great off axis.
I have the Alpair 5.2 s also. But they are still in the box. I bought them on sale. I think they would be great as mid-woofers in a WAW. I am currently re-thinking my current setup. A more compact design with sub-woofer support, maybe.
I have the Alpair 5.2 s also. But they are still in the box. I bought them on sale. I think they would be great as mid-woofers in a WAW. I am currently re-thinking my current setup. A more compact design with sub-woofer support, maybe.
You could do a folded transmission line with the folds going left to right therefore keeping the box shallow. There are plenty of Transmission line enthusiasts on this forum that may be willing to help with that.
Going sealed may help with reducing some of the built in baffle step as the roll off would start from about 200Hz if I remember correctly.
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That is good to hear. I haven't heard any other FR drivers but I do think the dispersion on the alpairs is actually pretty good when moving side to side. I can't imagine other FR drivers are as good based on what I have read about their directionality.
I will have to decide on the cabinet depth and drivers soon so I can figure out the rest. I think you are right about the rolloff around 200hz, so maybe that would be helpful. I'm hoping to have a good look at this all tomorrow, but I have quite a busy week unfortunately and every time I look into this project I end up reading for hours
How about the Tang Band W5-1138SMF 5-1/4"
Looking for a Tang Band W5-1138SMF woofer? - SoundImports
Does -6dB 50Hz in a 4.5 litre box.
I was considering this driver before but I wasn't sure on the fidelity compared to a dedicated midwoofer. I didn't realise it goes low in such a small box. The ferrite version can be had for cheap, the neo one is bit more expensive but it seems to have a smoother response and I think it rolls off later. I wonder if that is related to how well the driver plays up after the sub frequencies
As the stuffung in the port increase in desnsity the box moves from BR thru an aperiodic phase until such time as the density becomes essentially solid.
dave
I can perhaps help. I have worked thru quite a few schemes in my head and in wood.
The actual TL is not super critical. It just needs to have sufficient volume and the distance from the driver to the terminus has to go thru a lot of stuffing (ie it has to be a certain length).
dave
I think Stal needs to upload a new photo because I have seen that one with the pluvias several times and we all want to see the 7ms in their full glory 😀
Any suggestions would be helpful or pointers in the right direction so I can work on something. I'm basically doing my best to learn things as I go
MidWoofers? You mean midTweeter?
Add the Alpair 7.3 (and the P7HD) to the A7ms and A5.2/3 you have my favorite 3 (4) midTweters. The mono suspension have a distinct advantage in terms of really small bits of infomation not getting lost in the fight between the spider and the surround.
As it turns out i am working thru a WAW concept with A5.2 (or any 3 or 4” FR). It comes about because someone asked the innocent query: “what happens when you hook 2 drivers in parallel with the other driver in series". Turns out that once one goes down the rabbit hole to answer that question there are many possible combos, mostly dicarded in the past due to the assymetrical SPL of the drivers. This version uses a single midTweeter, but i have a version that uses 3 of them as well. With a single midTweeter te midTL is half-wave since i have a ton of volume to work with.
The “mono-pole” one requires 12-24Ω woofers. Unfortunately the Silver Flutre here are only sourced thru the USA.
dave
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Ah mid-tweeter yes.
7MS pics to follow. I got the grey ones.
I am thinking of getting another pair to have two per sealed box with a shunt cap on one of them. To be used with sub or subs.
Then I would use the SPH-8M with the Alpair 5.2 in a separate project. I would like to see how compact I could get it. The SPH-8M can go down to 10 litres with Qtc still under one. I was wondering how far approximately the Qtc could be reduced by making that box aperiodic?
I have done some twin boxes but am going to add some 3 driver boxes (4Ω drivers needed, and an amp happy with 12Ω in the bass.
This is the XO scheme for the all series configuration (ignore the text, it is a leftover, i have to add more appropriate ranges with more explanation of the what makes for the range..
Wiring 2 togther (series or parallel) is also possible and brings some interesting options.
dave
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After spending an exhausting amount of time looking at different woofers, I have found a couple more candidates, which are two SEAS drivers:
First of all the SEAS CD22RN4X which can do something like 59hz -3db in 15 litres, and secondly the L22RN4X/P which does about -3db at 55hz with 15 litres. I was just taking down -3db points as it's what the calculator I was using was outputting.
Datasheet for the CD22RN4X
Datasheet for the L22RN4X/P
The issue I see with the L22RN4X/P is that it has a very small usable bandwidth and it wont be as flexible on the XO. I was also worried about the large breakup around 3k.
So I think the best I have found so far for a compact size is the CD22RN4X. The woofer search is pretty tiresome so I will consider that later and assume the box will be about 150mm deep if clearance from the back of the driver isn't a concern. Would appreciate it if anyone can point out any issues with the CD22RN4X
First of all the SEAS CD22RN4X which can do something like 59hz -3db in 15 litres, and secondly the L22RN4X/P which does about -3db at 55hz with 15 litres. I was just taking down -3db points as it's what the calculator I was using was outputting.
Datasheet for the CD22RN4X
Datasheet for the L22RN4X/P
The issue I see with the L22RN4X/P is that it has a very small usable bandwidth and it wont be as flexible on the XO. I was also worried about the large breakup around 3k.
So I think the best I have found so far for a compact size is the CD22RN4X. The woofer search is pretty tiresome so I will consider that later and assume the box will be about 150mm deep if clearance from the back of the driver isn't a concern. Would appreciate it if anyone can point out any issues with the CD22RN4X
On 1st look neither of those have a decent FR, L22 has a wicked peak, the CD22 even more liited in response.
I do not like that strange shelving of the FR.
dave
I do not like that strange shelving of the FR.
dave