Hi all. I've posted a few times here before regarding a few different ideas for a WAW. I have been going back and forth on different ideas for what I want for months now, and now I've decided what I finally want and would appreciate any help. I've been reading for hours every day trying to find answers to questions, but I still need some advice so I thought it would be best to ask here. Don't be scared off by the wall of text that's about to follow.
My design goals are this:
- Sealed midwoofers crossed over to Alpair 7ms (these are the drivers I have and I'd like to stick with for now)
- Tight bass with good dynamics, hoping for some really quick transients
- Shallow depth (Max 200mm, less the better, I have been inspired by these - HTS11 On-Wall Loudspeaker | ATC Loudspeakers - which are ATCs monitors but turned into a wall mountable edition). I also like the idea of minimising baffle step loss and the delay in reflections from the back wall
- F6 50hz or less
- Listening distance will be 1m most of the time, will likely be used for PC use only. At most, probably 3m if they are to be moved
- Mostly listen at moderate volumes, about 85db-90db. I do like to rock out from time to time though, so maybe 95db+ volume. Never actually measured my listening volume
- Digital XO around 200hz
So I have a few questions. Firstly, midwoofer wise I was looking at the Dayton Audio RS225 (inspired by XRK). It looks great, measures well and comes in at a good price. My only issue is that putting this driver in a shallow enclosure around 24 litres results in something rather big. Once the alpair enclosure is on top, it'd be around 600mm tall or wide, depending on what way round the enclosure is orientated. I was wondering if anyone knows of similar quality woofers that can live in a smaller enclosure whilst still retaining reasonable extension. I have seen the SB Acoustics SB17CAC35-8 but haven't modelled this in winisd yet.
I would appreciate some advice around the XO. The 7ms seems to have a rising bass response which I assume is to compensate for baffle losses. I was hoping to use a 6db per octave xover but this basically counteracts that if crossing around 200hz. If I were to still use a 6db slope, would this result in the woofers and alpairs summing and creating esentially a bass heavy speaker, or would this have other adverse effects? I generally prefer my speakers with a bit of extra bass. Here is a link to the freq response of the 7ms - https://www.markaudio.com/wp-content/uploads/2019/06/Alpair-7MS-spec-final.pdf
My third question is how shallow can you really go before this having a negative effect on the cabinet reflections. I read somewhere with long bass waves, this isn't so much of an issue and it just ends up as pressure in the cabinet rather than a reflecting wave, but I am not sure.
I think my final question for now is would it be okay to leave the 7ms ported. I ask this because I wonder if the sound will be effected by any group delay. When I'm simluating it sealed, I can't really think of how I can create a 6db per octave slope. I also feel like I would need to create a sealed box and actually measure it to see how it behaves in real life as the rolloff on winisd doesn't seem to match up to the datasheet (as in it starts rolling off earlier in winisd).
I do have a measurement mic and am willing to put time into this project, but what I don't want to do is spend a year on this and then realise I'm not very happy with the sound.
Any help would be appreciated
My design goals are this:
- Sealed midwoofers crossed over to Alpair 7ms (these are the drivers I have and I'd like to stick with for now)
- Tight bass with good dynamics, hoping for some really quick transients
- Shallow depth (Max 200mm, less the better, I have been inspired by these - HTS11 On-Wall Loudspeaker | ATC Loudspeakers - which are ATCs monitors but turned into a wall mountable edition). I also like the idea of minimising baffle step loss and the delay in reflections from the back wall
- F6 50hz or less
- Listening distance will be 1m most of the time, will likely be used for PC use only. At most, probably 3m if they are to be moved
- Mostly listen at moderate volumes, about 85db-90db. I do like to rock out from time to time though, so maybe 95db+ volume. Never actually measured my listening volume
- Digital XO around 200hz
So I have a few questions. Firstly, midwoofer wise I was looking at the Dayton Audio RS225 (inspired by XRK). It looks great, measures well and comes in at a good price. My only issue is that putting this driver in a shallow enclosure around 24 litres results in something rather big. Once the alpair enclosure is on top, it'd be around 600mm tall or wide, depending on what way round the enclosure is orientated. I was wondering if anyone knows of similar quality woofers that can live in a smaller enclosure whilst still retaining reasonable extension. I have seen the SB Acoustics SB17CAC35-8 but haven't modelled this in winisd yet.
I would appreciate some advice around the XO. The 7ms seems to have a rising bass response which I assume is to compensate for baffle losses. I was hoping to use a 6db per octave xover but this basically counteracts that if crossing around 200hz. If I were to still use a 6db slope, would this result in the woofers and alpairs summing and creating esentially a bass heavy speaker, or would this have other adverse effects? I generally prefer my speakers with a bit of extra bass. Here is a link to the freq response of the 7ms - https://www.markaudio.com/wp-content/uploads/2019/06/Alpair-7MS-spec-final.pdf
My third question is how shallow can you really go before this having a negative effect on the cabinet reflections. I read somewhere with long bass waves, this isn't so much of an issue and it just ends up as pressure in the cabinet rather than a reflecting wave, but I am not sure.
I think my final question for now is would it be okay to leave the 7ms ported. I ask this because I wonder if the sound will be effected by any group delay. When I'm simluating it sealed, I can't really think of how I can create a 6db per octave slope. I also feel like I would need to create a sealed box and actually measure it to see how it behaves in real life as the rolloff on winisd doesn't seem to match up to the datasheet (as in it starts rolling off earlier in winisd).
I do have a measurement mic and am willing to put time into this project, but what I don't want to do is spend a year on this and then realise I'm not very happy with the sound.
Any help would be appreciated
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Sound can be just changing pressure in the box or a sound wave front.
An exploding bomb often has a wave front you can see which distorts the air.
I try to bypass all the complicated cabinet stuff and cross overs by using full range drivers in a half decent sized sealed box. I have a pair of Fane 12-250TC's in a box and that works great for me. If you want full fidelity then maybe a full ranger with a sub might be a better solution.
An exploding bomb often has a wave front you can see which distorts the air.
I try to bypass all the complicated cabinet stuff and cross overs by using full range drivers in a half decent sized sealed box. I have a pair of Fane 12-250TC's in a box and that works great for me. If you want full fidelity then maybe a full ranger with a sub might be a better solution.
I appreciate your input. I do have a sub but I would like some midwoofers to add a bit more versatility and headroom. Them big drivers look great and have very nice sensitivity, but I'm guessing the box they are in is pretty large. I am aiming for something reasonably compact.
Dave is very helpful and I have been in contact with him in the past. I was hoping to use something like his CGR design on top of the sealed bass box
That RS225 woofer is the woofer for small bass cabinets. I don't know an other woofer that can live in such a small space and can go low enough. This is the hoffman iron law, loud (in this case efficient to meet up with the 7MS), low and small, are not possible, you can only have 2 of this factors. So you need to make choices...
I use in my waw the Scanspeak 26W8534G00. That is a 10" woofer and i use it in a 77L sealed cabinet to meet with my Alpair 10.3 at 250hz with a 1st order serial CR. That hits an F6 of 30Hz and the whole system is 86-87dB efficient. But the bass cabinet is rather large...
I use in my waw the Scanspeak 26W8534G00. That is a 10" woofer and i use it in a 77L sealed cabinet to meet with my Alpair 10.3 at 250hz with a 1st order serial CR. That hits an F6 of 30Hz and the whole system is 86-87dB efficient. But the bass cabinet is rather large...
Hi Waxx. I appreciate the RS225 does do well in a reasonably small box. I was hoping there would be something that may require a slightly smaller box, even if it means giving up some low end ultimately. I have been looking round but haven't been able to find much, or a current driver that might fit the job. I do think the 8" will have the dynamics I'm after, especially compared to a 6".
Sensitivity wise, I was hoping to get away with the close wall positioning and biamping to make this not an issue. Ideally I would like a sensitive woofer but I know that this probably isn't going to be possible if I go smaller.
If I can't find a driver that fits a smaller box, I will have to either increase the depth, or the box Q, I was trying to keep it around 0.707.
Ideally I would have a big speaker like yours but I don't think I will be able to find any place for such a big box unfortunately
Sensitivity wise, I was hoping to get away with the close wall positioning and biamping to make this not an issue. Ideally I would like a sensitive woofer but I know that this probably isn't going to be possible if I go smaller.
If I can't find a driver that fits a smaller box, I will have to either increase the depth, or the box Q, I was trying to keep it around 0.707.
Ideally I would have a big speaker like yours but I don't think I will be able to find any place for such a big box unfortunately
Small sealed bass enclosure. Boy do i miss the SDX7. It gets into the mid 20s with a tiny bit of boost at 25 Hz. In a 14 litre sealed box.
The driver, with a Foster plate amp with that 25Hz boost, all nicely fit into a 1 foot cube (external).
I am working on retrofitting A7ms into my WAW currently with A7.3eN and 2 x SDX7. Way less than 200mm deep. But wide. I have to design & 3D print a couple of adaptors.
I figure A7ms and A5.2/3 are currently my lead choices for midTweeters.
The driver, with a Foster plate amp with that 25Hz boost, all nicely fit into a 1 foot cube (external).
I am working on retrofitting A7ms into my WAW currently with A7.3eN and 2 x SDX7. Way less than 200mm deep. But wide. I have to design & 3D print a couple of adaptors.
I figure A7ms and A5.2/3 are currently my lead choices for midTweeters.
Hi Dave, I've always liked the look of those speakers. I saw you mention those drivers when I was looking round for sealed drivers, I don't think they're available anywhere unfortunately. Do you know any other alternatives?
I wanted to make mine wide baffle too for the benefits and then place them close to walls. Sort of as close to an in wall speaker as I can get. I always have to place my speakers by the wall anyway so I thought this might work.
Glad to hear you like the 7ms, do you have any suggestions on XO? I am going to do an experiment soon by just crossing over some other speakers to see what I can do
I wanted to make mine wide baffle too for the benefits and then place them close to walls. Sort of as close to an in wall speaker as I can get. I always have to place my speakers by the wall anyway so I thought this might work.
Glad to hear you like the 7ms, do you have any suggestions on XO? I am going to do an experiment soon by just crossing over some other speakers to see what I can do
I am planning on using a 1st order version of Nelson's 6-24 active XO. Iy will also likely work with the same PLLXO as used with the A7 version. It doesn’t have the right filter for my current 1st choice midTweeter amp.
Given the low XO, biamping makes the most sense, but depending on woofer choice and box design you have a wide range of possible XO points.
I have searched (not too hard) for a suitable sub for the SDX7 but have yet to succeed. With enuff of a push the new CSS has indicated that an SDX7 or SDX7.2 (there is one tweaks that absolutely sneed doing) is a real possibility. I have at least 8 SDX7eN but i think all my excess went out in the summer.
dave
Given the low XO, biamping makes the most sense, but depending on woofer choice and box design you have a wide range of possible XO points.
I have searched (not too hard) for a suitable sub for the SDX7 but have yet to succeed. With enuff of a push the new CSS has indicated that an SDX7 or SDX7.2 (there is one tweaks that absolutely sneed doing) is a real possibility. I have at least 8 SDX7eN but i think all my excess went out in the summer.
dave
Seas L26ROY can go reasonably low and can be in pretty small box when sealed. Only downside might be sensitivity, but didn't you considered biamping? I already ordered mine for WAW (with sonido fieldcoil fullrangers). But I plan to use them ported and biamped.
You can go as shallow as you like, there are some shallow woofers that might be worth looking at. You can make the box small, raise the resonance above the crossover point and EQ below, that will give you "fast", "tight" bass. You'll get quite a boost from having them against the wall anyway.
Thanx. I’ll have a look at that one. If used on the bottom the really ugly 3kish peak will likely not be a big issue, but it could rrsond well to a coat of modPodge front & back.
It is very pretty. The silver MAs would match well, the copper a nice contrast with the sam ekind of metal finish.
dave
That is a nice looking driver but very expensive. I should have said my budget is probably up to £120 per driver.
My main concern with xo is how the freq response isn't very flat around 200hz. Once I experiment with it I'll see how it sounds, and I need to read more on xovers to give myself a better understanding.
Even if you had some to sell I think the tax from Canada to UK would be extreme so that wouldn't be an option unfortunately.
Thanks for the tip. I will look into this some more.
I will report back on any suitable woofers for my application if anyone is interested.
Just the VAT. Which likely wouldn’t be hard if you could afford the driver cost & the shipping. They are worth about $100USD each stock, 2x that EnABLed.
dave
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A Dayton RS180-4 midbass driver can get 45.5Hz F6 in a 17L sealed. Maybe that is what you are after if it's low enough. Driver is 60€ down here and it's a very good driver. It won't go that low loud (max 92dB says sim), but you said you don't need it loud...
A driver that can get louder, but less low (50Hz F6) in the same space sealed is the Tang Band W8-670T, that cost more or less the same. But i got no experience with it, i just go from published specs on this.
A driver that can get louder, but less low (50Hz F6) in the same space sealed is the Tang Band W8-670T, that cost more or less the same. But i got no experience with it, i just go from published specs on this.
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This is something I will have to consider as the drivers do seem perfect for what I need, however I was hoping to purchase the woofers once I have everything else figured out on paper. I also love the look of enabled drivers
Thanks for sharing that, seems interesting but quite complex for a beginner like me. I had a quick read but will have to revisit it when I have a bit more time on my hands
Thanks for the suggestions. I think the rs225 will do something similar at that size, I will check the numbers when I am next on my PC and report back. I have a feeling 24l is a little on the larger side of what it needs