I'm heading towards my next build for a pair of stereo desktop speakers. Crossover points will be established through testing, but there is a fair chance that the final decision would be considered a wide-range assisted design. At least, I'm intending to use a "full-range" driver as a wide mid-range, or beyond. So in the absence of clairvoyancy I'm posting here.
The drivers I've chosen after some testing are the Alpair 7ms and SB23MFCL45. The former will go to below 80hz at -6db in a 5L sealed box - though I intend to high-pass them as part of an (active) crossover, and might also try a tapered aperiodic design. The latter are technically called subwoofers but only have a 6.5" effective cone diameter and will go up towards 200hz, which seems high enough for woofer assistance (my aim is stereo, not a sub+sats). They'll reach down to about 37hz at -6db in a 23L box, which is pretty much what I want (though they could go lower with EQ if wished; I'm listening at less than 1m, so am not needing massive SPL/excursion).
These 'may' be joined by a pair of 19mm SB tweeters crossed at several khz or more, but I've not decided yet. I'm not against tweeter-assistance, and in testing I do slightly prefer their contribution. However I have old enough ears that their benefits are fairly small over the 7ms alone, so I might not bother with tweeters at all. We aren't very sensitive to a lot of subtleties at very high frequencies but even so, achieving properly good integration (including stuff like controlled directivity) would be reasonably involved.
The drivers I've chosen after some testing are the Alpair 7ms and SB23MFCL45. The former will go to below 80hz at -6db in a 5L sealed box - though I intend to high-pass them as part of an (active) crossover, and might also try a tapered aperiodic design. The latter are technically called subwoofers but only have a 6.5" effective cone diameter and will go up towards 200hz, which seems high enough for woofer assistance (my aim is stereo, not a sub+sats). They'll reach down to about 37hz at -6db in a 23L box, which is pretty much what I want (though they could go lower with EQ if wished; I'm listening at less than 1m, so am not needing massive SPL/excursion).
These 'may' be joined by a pair of 19mm SB tweeters crossed at several khz or more, but I've not decided yet. I'm not against tweeter-assistance, and in testing I do slightly prefer their contribution. However I have old enough ears that their benefits are fairly small over the 7ms alone, so I might not bother with tweeters at all. We aren't very sensitive to a lot of subtleties at very high frequencies but even so, achieving properly good integration (including stuff like controlled directivity) would be reasonably involved.
The constraints of desk space have encouraged me to consider side-firing woofers. As furniture might be close to the desk sides, and as desk space is also a premium, having them in separate cabinets offers a lot more flexibility. A previous thread has suggested that this is fine if the woofers are located within 1/4 wavelength distance of the midrange, and/or used below a couple of hundred hertz, depending on people's views. Which suits the intended crossover frequency quite well.
I posted this in another thread as an example of that thinking. It is just a crude and imprecise concept (and very oversimplified drawing!), but it hopefully illustrates where my thoughts are starting with this thread, as I head towards a final design:
(monitor shown as translucent to help illustrate)
Cheers,
Kev
I posted this in another thread as an example of that thinking. It is just a crude and imprecise concept (and very oversimplified drawing!), but it hopefully illustrates where my thoughts are starting with this thread, as I head towards a final design:
(monitor shown as translucent to help illustrate)
Cheers,
Kev
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from a studio engineers perspective, while I’m a DIY guy at heart, for the $$$ considering the effort, you’re not going to build a better sounding more co pact solution than a pair of iLoud micro monitors for your use……these things punch way above their price point. I travel with a pair for edits in hotel rooms or small space no treated control room monitoring.
The iLoud mini monitors look very nice, so thanks for suggesting them. But yes, the aim here is to make something myself, and so preferably something a little more unusual than most mini monitors and 2-ways.
I agree there'd be less value in duplicating successful designs like the iLouds, that are already cheaply available. In fact for similar reasons I might possibly choose to buy amps or amp modules, since (with my lowly skills) I'm unlikely to be able to do it better or cheaper. If class-D anyway, perhaps there'd be more value to it if I went with class-A. But I do think that speakers and in particular their cabinets continue to offer the DIYer useful scope for more personal designs.
In my case I don't need these to be absolutely tiny, as they don't have to be carried around. It would just be nice if they didn't take up lots of space around the working area at the front of the desk, which is why I'm looking at suspending the small midrange cabinet off the desk by several inches or more, and putting the woofers further back and/or at the sides. I see this as taking advantage of the low WAW-like crossover point, rather than the more typical midwoofer+tweeter that a lot of commercial designs use.
Cheers,
Kev
I agree there'd be less value in duplicating successful designs like the iLouds, that are already cheaply available. In fact for similar reasons I might possibly choose to buy amps or amp modules, since (with my lowly skills) I'm unlikely to be able to do it better or cheaper. If class-D anyway, perhaps there'd be more value to it if I went with class-A. But I do think that speakers and in particular their cabinets continue to offer the DIYer useful scope for more personal designs.
In my case I don't need these to be absolutely tiny, as they don't have to be carried around. It would just be nice if they didn't take up lots of space around the working area at the front of the desk, which is why I'm looking at suspending the small midrange cabinet off the desk by several inches or more, and putting the woofers further back and/or at the sides. I see this as taking advantage of the low WAW-like crossover point, rather than the more typical midwoofer+tweeter that a lot of commercial designs use.
Cheers,
Kev
I have a similar interest 
a first design. Interest in trying this for a long time. Measurement is well covered now so .......... and ARTA looks to be the best option for me due to tutorials.
I want to try 2 way using a low resonance 4" driver. Visaton have a suitable unit so first step is see what can be done with that on paper. Still not sure about which software to use for this.
Upper range - I noticed some Packard Bell PC speakers on ebay, dml panels with a woofer cheap so bought them as dml's interest me. Implementation is poor and a bit short on max sound levels. That may be down to age or design. If this doesn't work out there is always the option of using wide range 2nd speaker. Also adding a separate woofer but I'm not convinced that is essential.
a first design. Interest in trying this for a long time. Measurement is well covered now so .......... and ARTA looks to be the best option for me due to tutorials.I want to try 2 way using a low resonance 4" driver. Visaton have a suitable unit so first step is see what can be done with that on paper. Still not sure about which software to use for this.
Upper range - I noticed some Packard Bell PC speakers on ebay, dml panels with a woofer cheap so bought them as dml's interest me. Implementation is poor and a bit short on max sound levels. That may be down to age or design. If this doesn't work out there is always the option of using wide range 2nd speaker. Also adding a separate woofer but I'm not convinced that is essential.
Interesting. I had never known or thought that a cheap set of computer speakers will use DML technology. Below are the specifications, pulled from its manual Packard Bell Model FPS100
Satellites are crossed at 200Hz, which aligns with the experience of DML users on the forum (they can't do bass too well).
That SNR though.
I'd like to see somebody try and replicate this, but better, utilizing modern construction methods and understanding
Satellites are crossed at 200Hz, which aligns with the experience of DML users on the forum (they can't do bass too well).
That SNR though.
I'd like to see somebody try and replicate this, but better, utilizing modern construction methods and understanding
LOL I don't know about understanding but I'll give it a go. The speakers don't sound too bad but the amp is very poor. Tone is set via a woofer volume control. It clips and I suspect the unit is meant to sound boomy. I can test the panels on their own. That gives some idea what a panel of that size, aspect ratio and wattage can do. Other sizes etc will need constructing from scratch but at least I have a guide of sorts.
Unlike most of the people in the dml thread I do feel it's worth looking at commercially produced ones when I can. Not that there is anything revolutionary about these.
Thanks everyone. Yes the bowls are a strong possibility, as I've used them before and would like fairly big round-overs anyway. Though I'd still be tempted to add a long tapering shape to the pack of them and stuff aperiodically; it is something I've not tried before yet it appeals to me. I suppose that would look something like the smaller driver's sections in those Nautilus (snail-like) speakers that I could never aspire to afford.
The horn tweeter is also something I'm very keen to use, when I build some room-sized speakers in a future project. Though for this project (a modest desktop system) I've proven to my satisfaction that just a couple of cone drivers (possibly plus a super-tweeter) can easily provide the frequency range and SPL required, so that is currently the direction I'm going in here.
It is relatively unusual for me to not be chasing higher SPL. So I'm particularly keen to take advantage of this in getting a wide-range out of the mid driver. The tweeter crossover (if there is one) could then be at high enough frequencies that we lose the ability to discern very much. The low crossover could be low enough for ideal driver spacing of less than a quarter wavelength. A few tests have been very positive for clarity and imaging, especially when also listening near-field which helps to simplify room effects, so I'm quite excited by the approach.
Cheers,
Kev
The horn tweeter is also something I'm very keen to use, when I build some room-sized speakers in a future project. Though for this project (a modest desktop system) I've proven to my satisfaction that just a couple of cone drivers (possibly plus a super-tweeter) can easily provide the frequency range and SPL required, so that is currently the direction I'm going in here.
It is relatively unusual for me to not be chasing higher SPL. So I'm particularly keen to take advantage of this in getting a wide-range out of the mid driver. The tweeter crossover (if there is one) could then be at high enough frequencies that we lose the ability to discern very much. The low crossover could be low enough for ideal driver spacing of less than a quarter wavelength. A few tests have been very positive for clarity and imaging, especially when also listening near-field which helps to simplify room effects, so I'm quite excited by the approach.
Cheers,
Kev
Thanks, that is an interesting little video. I've not seen those DSP modules before; I'm intending to use software at the source (and output via a multi-way DAC), but a stand-alone active speaker might be nice sometimes. I wonder if the module's effect on sound-quality (distortion, noise etc) is good enough for high end use, or if they're best for cheap and cheerful applications.
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Look at the price and you'll quickly know what they lean towards
These chips have been on the market for some time, either standalone or integrated directly into amps or audio products.
I believe some dislike using them because of the built-in DAC.
Either way I'm also looking at various means to do DSP. Hopefully I can learn something from your build Kev
These chips have been on the market for some time, either standalone or integrated directly into amps or audio products.
I believe some dislike using them because of the built-in DAC.
Either way I'm also looking at various means to do DSP. Hopefully I can learn something from your build Kev
Thanks, yes that was the concern. I've moved away from assuming price is necessarily an indicator of performance, at least with small signal electronics, but only within reason. They're very interesting though, I can see myself using them for other projects. Just that I'm aiming for high quality with this one, even though 'reasonably' compact and low SPL.Look at the price and you'll quickly know what they lean towards
These chips have been on the market for some time, either standalone or integrated directly into amps or audio products.
I believe some dislike using them because of the built-in DAC.
Either way I'm also looking at various means to do DSP. Hopefully I can learn something from your build Kev
My plan for DSP and crossovers (and pre-amp etc) is currently to do it at source, since my only source these days is a fanless PC. I've got a multi-way DAC and will need to decide what power amps to use once the drivers and their power requirements are finalised. I've done this before successfully, but this time I'm going to try it with Linux and probably something like CamillaDSP, so quite a lot to learn and sort out before this project is completed.
Thanks, yes I will probably use some other shape in the final thing. It is very likely to be round or spherical, though if my wish for a tapering cone shaped rear enclosure comes to fuition that might be triangular; if so I might make the front baffle respect it in some way just to be a bit different.
Though this won't be a flat baffle, it'll be significantly radiussed or have big chamfers. I'm sure people have seen the classic work by Olson. This is a version that Planet10 posted:
When the baffle edges are removed enough to make a truncated pyramid, a square box is almost as good as a sphere. Though IMO one mistake lots of people make with this is scale; the driver needs to be relatively small in relation to the baffle shape for it to work this well (cramming a speaker into a sphere that is little bigger than its diameter isn't the same). I'm a little constrained on that, but at least a well rounded baffle shape is looking safest at the moment.
Cheers,
Kev
Best to look rather than assume
https://www.analog.com/en/products/adau1401.html#product-overview
Not suitable for new designs suggest that better is available. They spec it at a 48khz sample rate and out put filtering is simple. It can sample up to 192khz. It's 24bit.
https://ez.analog.com/audio/f/q-a/96492/problem-of-adau1401-working-at-192khz-sampling-rate
Rise time = 0.35/F3 so at 20khz the rise time is 17.5usec.
I wonder about that but it's a complicated subject. For instance say an infinite rise time square wave is put in the output will have a rise time but the corners will be rounded by some degree and rise time is measured from 10 to 90%.Anyway the DSP boards performance can be checked in the usual way with the usual kit.
Ubuntu Studio LTS may be suitable. It comes geared up for sound mixing and etc but also a low latency kernel as it comes. It also uses the KDE desktop which I find more useful than Gnome - especially as Ubuntu comes.
I've used OpenSuse for ~25years as extremely stable and reasonably up to date applications and in many cases still easy to install more up to date popular ones. The current stable version is using experimental apps and ones i use regularly have problems. Sad really,No I am not a Linux console guru, the equiv of a dos box. I ask on a forum if needed or do some googling and just remember the few commands I actually use.
It can be dual booted with windows but DO find instructions on what to do. Windows can also be run in Oracle's VM if you have installation media.
I've read this can be done with dowloads from MS by not registering it when it's installed. Maybe not any more.
You seem to be heading towards something like this: https://www.kaliaudio.com/in-unf
Which is quite well-reviewed.
Some notes from me:
Chris
Which is quite well-reviewed.
Some notes from me:
- If you have enough amplifier power, sealed with EQ will allow a much more compact bass unit.
- In that direction, 2x 5" drivers on each side would mean a shallower bass unit, too.
- I don't expect that tweeters will be particularly needed. The smaller Alpair units do fine on their own IME
Chris
Thanks, it is useful to hear your experiences. I'm currently running my audio side of things as a virtual machine (on KVM/QEMU) with a USB pass-through for the DAC, so it would be easy enough to try different distros. Though I think my requirements are fairly easy; I'm simply playing music (rather than live recording, or synchronising with other things like video etc), so I'd be surprised if I needed a special low-latency distro. I'll certainly start a thread in the appropriate forum when I reach that stage, though.Ubuntu Studio LTS may be suitable. It comes geared up for sound mixing and etc but also a low latency kernel as it comes. It also uses the KDE desktop which I find more useful than Gnome - especially as Ubuntu comes.
No I am not a Linux console guru, the equiv of a dos box. I ask on a forum if needed or do some googling and just remember the few commands I actually use.
It can be dual booted with windows but DO find instructions on what to do. Windows can also be run in Oracle's VM if you have installation media.