I know this has been discussed to death, and the goal to build i a real full neutral studio monitor is a very high goal. But as i'm looking for something to make my radio broadcasts and amateur music mixing a bit better, i was looking arround in the studio monitor market and heared a lot of very bad cheap monitors. Good monitors exist off course but they all kost an arm and a leg. But the ones i can afford (<1K) are less revealing and translating well than my Mark Audio Alpair 10.3 reflex i use now so not worth the investment.
So i thought i may do better by try to build something myself than those cheaper ones i can afford. And even if i fail, the journey to get there will learn me a lot. I did build quiet a few not so neutral but good sounding fullrange speakers (at least to my opinion) and did study the subject for years. I did hear some very good kits like the Tango MT (owned by a friend) that are more like what i try to reach. I'm also inspired by that one, but as that tweeter is unavaileble, i had to change the plan. And no, i don't want to build a kit, the designing is half the fun and learns me something, kit's don't do that anymore.
I'm going to keep that Dayton RS180-4 driver and pair it with the exellent SB26ADC tweeter in a 2 way reflex. A waveguide could give it a broader and flatter dispertion, but i don't need that as i'm mixing in the box and i'm always at the same spot (in my chair on my desk). So i need a speaker that is relative flat on axis an go low enough to fit most music without a sub. Adding a waveguide would complicate this build for me a lot as i don't have the tools nor the skills to make one.
The plan i made is a 30L reflex tuned to 32Hz F3 wit a front slot port. It will be build in 18mm birch plywood. Crossover will be passive for the moment as good dsp chips and so are out of stock or way to expensive at the moment. I may convert it to active later on when that issue is resolved. The crossover in the plan is a starting point, calculated and simmed with regards to the alignment of the drivers and the offset of the woofer and so but based on published graphs. I'm going to measure off course when the cabinet is build and the drivers are mounted and adjust the crossover (but i needed a starting point and a check if the drivers can meet). BSC is not included as the speakers will be against a stone wall (which is not perfect, but that is what i have to deal with) that will make up for that largely. I will line the cabinet with felt and maybe even damp it with bitumen sheets (i got some leftovers from other builds in stock).
But before i start, it's maybe time for a reality check on obvious mistakes i made within this goal. Full plan is in the pdf attached like i would make for a publishing (which i will when it's finished). So shoot...
And for those who maybe want to build it, you can (as long as it's not a commercial thing) but at your own risk, it's not verified in reality. This is a first draw.
So i thought i may do better by try to build something myself than those cheaper ones i can afford. And even if i fail, the journey to get there will learn me a lot. I did build quiet a few not so neutral but good sounding fullrange speakers (at least to my opinion) and did study the subject for years. I did hear some very good kits like the Tango MT (owned by a friend) that are more like what i try to reach. I'm also inspired by that one, but as that tweeter is unavaileble, i had to change the plan. And no, i don't want to build a kit, the designing is half the fun and learns me something, kit's don't do that anymore.
I'm going to keep that Dayton RS180-4 driver and pair it with the exellent SB26ADC tweeter in a 2 way reflex. A waveguide could give it a broader and flatter dispertion, but i don't need that as i'm mixing in the box and i'm always at the same spot (in my chair on my desk). So i need a speaker that is relative flat on axis an go low enough to fit most music without a sub. Adding a waveguide would complicate this build for me a lot as i don't have the tools nor the skills to make one.
The plan i made is a 30L reflex tuned to 32Hz F3 wit a front slot port. It will be build in 18mm birch plywood. Crossover will be passive for the moment as good dsp chips and so are out of stock or way to expensive at the moment. I may convert it to active later on when that issue is resolved. The crossover in the plan is a starting point, calculated and simmed with regards to the alignment of the drivers and the offset of the woofer and so but based on published graphs. I'm going to measure off course when the cabinet is build and the drivers are mounted and adjust the crossover (but i needed a starting point and a check if the drivers can meet). BSC is not included as the speakers will be against a stone wall (which is not perfect, but that is what i have to deal with) that will make up for that largely. I will line the cabinet with felt and maybe even damp it with bitumen sheets (i got some leftovers from other builds in stock).
But before i start, it's maybe time for a reality check on obvious mistakes i made within this goal. Full plan is in the pdf attached like i would make for a publishing (which i will when it's finished). So shoot...
And for those who maybe want to build it, you can (as long as it's not a commercial thing) but at your own risk, it's not verified in reality. This is a first draw.
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The waveguide is not only about flat off axis response, but also about acquiring better power response. Have a look at the Heißmann-site. You will find he offers affordable waveguide adaptor plates too. And I think you are referring to the metal cone Dayton, in that case you need a low X-over frequency: a waveguide helps relieving the load on the tweeter.
Secondly, I’d put the port on the rear plus flare both ends symmetrically. And thus take measures the port noise doesn’t ruin my good intentions. A slot port seems less optimal.
Secondly, I’d put the port on the rear plus flare both ends symmetrically. And thus take measures the port noise doesn’t ruin my good intentions. A slot port seems less optimal.
Hi,
Rear port seems not wise as the loudspeakers will be located near back wall.
I wonder about the slot port too. Could'nt be a more typical round one be implemented ( flared or not)?
Like Markbakk i would consider a waveguide too but it may be too much a departure from your initial design idea?
While at departure from your initial idea i'm surprised you didn't go Full Range WaW/Fast Waxx. There isn't smaller fr driver which meet your criteria?
Rear port seems not wise as the loudspeakers will be located near back wall.
I wonder about the slot port too. Could'nt be a more typical round one be implemented ( flared or not)?
Like Markbakk i would consider a waveguide too but it may be too much a departure from your initial design idea?
While at departure from your initial idea i'm surprised you didn't go Full Range WaW/Fast Waxx. There isn't smaller fr driver which meet your criteria?
I prefer slot ports to be honest, tube ports made of plastic are to flimsy and i can hear them ringing often and they tend to be longer than slots for the same tuning. The slot is calculated to have a very low air velocity (<17ms) at the volumes i will use it, and on max it's still at 17 which should not be hearable. Flaring the port will be done as much as possible with the roundings i do at the box. And the port must be at the front as the speaker will be against a wall. I also don't like backported speakers as you hardly can control the response of that port when it's not in the middle of the room (always loading something).
And a waw will be to big. I did try that with a lower crossover point, but it can't sit on a desk like that as it becomes to big. The fr also need space and can't be in the same space as the woofer. And as much as i like fullrange drivers, dome tweeters are still more neutral (as the resonance is way higher) and have a better dispertion even without waveguide. So if that is the goal, a dome tweeter was a better option.
On waveguides, i know the advantages, but i also know my building skills and the only one that would fit is the ovale one. Cutting a hole like that is beyond my woodworking skills and i don't have a 3d printer to print it nor have access to one (or the skills to use it). I may build other speakers later on with that, but this tweeter is used lower in good sounding speakers than i do cross it (at 1800Hz more or less). Troels did measure those and there you can see you can cross these way lower as the distortion is very low at that frequency. That's why i like this dome tweeter so much.
SBAcoustics-tweeters
But still thanks for the comments and thoughts, it's always interesting to hear feedback.
And a waw will be to big. I did try that with a lower crossover point, but it can't sit on a desk like that as it becomes to big. The fr also need space and can't be in the same space as the woofer. And as much as i like fullrange drivers, dome tweeters are still more neutral (as the resonance is way higher) and have a better dispertion even without waveguide. So if that is the goal, a dome tweeter was a better option.
On waveguides, i know the advantages, but i also know my building skills and the only one that would fit is the ovale one. Cutting a hole like that is beyond my woodworking skills and i don't have a 3d printer to print it nor have access to one (or the skills to use it). I may build other speakers later on with that, but this tweeter is used lower in good sounding speakers than i do cross it (at 1800Hz more or less). Troels did measure those and there you can see you can cross these way lower as the distortion is very low at that frequency. That's why i like this dome tweeter so much.
SBAcoustics-tweeters
But still thanks for the comments and thoughts, it's always interesting to hear feedback.
If it is nearfield listening the power response shouldn't matter as much. Certainly it wouldn't hurt if it was good though. There is at least one surface nearby, the desk, and maybe a wall behind the speakers.
While I haven't thought through what would make a good nearfield monitor I'm sure one would want the mid and tweeter very close together, coaxial would be best, in terms of stability of the sound if you move a little. If speakers are very close to the listener little movement puts you many degrees off-axis, especially the vertical axis can move a lot more than with farfield listening sitting down on a sofa. If you are not careful about the speaker positioning the sound could change a lot if you lean forward to see the text on the screen or lean back to chill out a bit.
I would make it three way and use very good drivers to further better typical cheap commercial nearfield monitors but at this point cost shoots up.
I suspect you cannot match quality of commercial offerings with less money unless very high price range. So be aware there is possibly no money savings available. Build something that you think you need, a tool for a specific job and the price shouldn't matter too much. If you don't know exactly what you need then it is purely a learning experience and you would get the job done cheaper by using commercial speakers.
My point was not to let you down but encourage to think the problem broadly to be able to set good design goal for your needs. If you then achieve the good goal, you should have a nice set of speakers that get lot of use. Have fun! 🙂
While I haven't thought through what would make a good nearfield monitor I'm sure one would want the mid and tweeter very close together, coaxial would be best, in terms of stability of the sound if you move a little. If speakers are very close to the listener little movement puts you many degrees off-axis, especially the vertical axis can move a lot more than with farfield listening sitting down on a sofa. If you are not careful about the speaker positioning the sound could change a lot if you lean forward to see the text on the screen or lean back to chill out a bit.
I would make it three way and use very good drivers to further better typical cheap commercial nearfield monitors but at this point cost shoots up.
I suspect you cannot match quality of commercial offerings with less money unless very high price range. So be aware there is possibly no money savings available. Build something that you think you need, a tool for a specific job and the price shouldn't matter too much. If you don't know exactly what you need then it is purely a learning experience and you would get the job done cheaper by using commercial speakers.
My point was not to let you down but encourage to think the problem broadly to be able to set good design goal for your needs. If you then achieve the good goal, you should have a nice set of speakers that get lot of use. Have fun! 🙂
Few things why I'd build a quick mono prototype first to measure the performance of your plan. Size of the box as well as the slot port.
30 litres is so big it will have lots of standing waves inside and a slot port, if the inner opening is at the boundary of the enclosure, will leak most of that stuff out. Another from the big volume: it usually means big baffle as well (big in relation to the drivers). This means lots of diffraction related ripple on axis as big as many decibels which prevents you to get the on-axis performance anywhere near flat. Plan in extensive slants/roundovers to minimize.
Anyway, buildin a one night quick and dirty prototype will tell if any of this is a concern or not before it is too late 😉 If these kind of basic issues are left in the system it is no better than the cheap commercial offerings in my opinion.
30 litres is so big it will have lots of standing waves inside and a slot port, if the inner opening is at the boundary of the enclosure, will leak most of that stuff out. Another from the big volume: it usually means big baffle as well (big in relation to the drivers). This means lots of diffraction related ripple on axis as big as many decibels which prevents you to get the on-axis performance anywhere near flat. Plan in extensive slants/roundovers to minimize.
Anyway, buildin a one night quick and dirty prototype will tell if any of this is a concern or not before it is too late 😉 If these kind of basic issues are left in the system it is no better than the cheap commercial offerings in my opinion.
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Waxx, your analysis/choices make sense.
The loudspeakers you talked about are Humbledeer's one isn't it? I can't remember which one they are. A Bagby's design?
The loudspeakers you talked about are Humbledeer's one isn't it? I can't remember which one they are. A Bagby's design?
It's Humbledeer's loudspeaker and it's indeed a Jef Bagby design. It uses the obsolete Dayton RS28A tweeter. I've heared it quiet a few times and it's a very good speaker, better than i heared commercially below a grand.
And tmuikku, the only monitor that is a bit good for that price is the JBL Studio 530. For the rest each one has issues with resonance and distortion peaks. I did not measure them all (some i did), but i heared it. Most cabinets are also not braced decent and resonate a lot when you tap them as they are build out of plastic or thin mdf. Even Genelec has it on some cheaper models. The only other one that was a bit ok was a dual concentric, the Tannoy Gold 8. But that cabinet resonates like hell...
I know the cabinet is big, that's why i want to use quality 18mm plywood, put bracing and plan lining with 8mm felt to conquer standing waves. I probally also going to ad some filling for that also in the upper part (after the tweeter but that will be trial & error. And i used that kind of slot ports before in other builds without issues or resonances. I know that works but you need to line the speaker enough. Rounding the cabinet corners is planned (if you saw the plan, you would have seen that). A round port would be about 4cm longer, and have a lower resonance frequency i calculated.
Btw: i plan it to look like this, which i think is not to wide for the drivers.
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I haven’t got a clue how one can use monitors against the front wall. The result will invariably be a very coloured sound. Do you have any acoustic measures against that in your plans?
Off course it wil, the room is not treated. But that does not mean you can try to build a more neutral speaker. It's not a pro audio setting, it's a home setup where i make radio broadcasts and do some mixing of own work or friends on a low budget. But that the room will be in play is sure, i realise that.
And i have some id's how to make the room better acousticly, but it will never be a pro studio or even close. That is not the goal and if it was, i would not assume i can do better than people who make a living of it and invest in decent monitoring and acoustics. But i got to do with what i have, a room in the old stone farm where i live that doubles as my office. And i know cheap monitors that i can buy don't do it, i'm rather sure that with my budget i can do better.
Good monitors exist..
What brand & type do you consider such a good monitor and why is that? (other than the fact they cost an arm and a leg?
What brand & type do you consider such a good monitor and why is that? (other than the fact they cost an arm and a leg?
I agree with you Waxx, you can make better than entry level monitors ( despite some being acceptable, i liked the Tannoy too or Cali in8 but have same concern about box).
But it'll cost more than the commercial offer: almost all of them are active and once you take into account amp and active filtering it is difficult to be competitive. Of course if you already have amp it wont be an issue but as the box is usually what cost the most in a loudspeaker, diy is still interesting within your budget and approach imho.
Boden: Genelecs 8531 and 8361 are very goods to me ( this is debatable as all preferences of course), and blameless specs. But they are not cheap ( even less with the subs).
But it'll cost more than the commercial offer: almost all of them are active and once you take into account amp and active filtering it is difficult to be competitive. Of course if you already have amp it wont be an issue but as the box is usually what cost the most in a loudspeaker, diy is still interesting within your budget and approach imho.
Boden: Genelecs 8531 and 8361 are very goods to me ( this is debatable as all preferences of course), and blameless specs. But they are not cheap ( even less with the subs).
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Yes, but my question was directed to Waxx.
For a lot less money the Neumann KH 80 comes pretty darn close to the Genelecs , and so do the Heissman designs. You have to be a very seasoned designer to even approach this level of uniform directivity- perfection with diy.
For a lot less money the Neumann KH 80 comes pretty darn close to the Genelecs , and so do the Heissman designs. You have to be a very seasoned designer to even approach this level of uniform directivity- perfection with diy.
I like ATC (all i heared), Klein & Hummel O300 (now Neumann but i did not hear actual versions) and Genelec 8320a or 8351 for their neutral sound for monitoring. Idem with Kii audio BXT (only heared them once, but they were so convincing). There are more that are ok (Focal, PMC, Barefoot, ...) but those stand out for me. I did not hear them all off course.
The ones i did not like that are also kind of expensive are dynaudio BM5A, KRK (all), Yamaha (all), Tannoy reveal, Adam (i hate that tweeter for monitoring), ...
Link to datasheeet has deceased (on top of that it was only for the preliminary version) 😉
https://www.scan-speak.dk/datasheet/pdf/d3404-552000.pdf
Test Bench: The New Ellipticor D3404/552000 Tweeter from Scan-Speak | audioXpress
OTOH the cost of the D3404/5520-00 may vaporize waxx's project budget 😉.
https://www.scan-speak.dk/datasheet/pdf/d3404-552000.pdf
Test Bench: The New Ellipticor D3404/552000 Tweeter from Scan-Speak | audioXpress
OTOH the cost of the D3404/5520-00 may vaporize waxx's project budget 😉.
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Your attenuation on the SB26ADC tweeter is pretty shallow. You are down about 10 dB at 1000 Hz... Do you think this is enough?
I used the very similar SB26CDC, I like it a lot. I crossed it at 1800 Hz LR4 and harmonic distortion was not a problem, subjectively it sounded really great... but I was attenuated by 22 dB at 1000 Hz.
j.
I used the very similar SB26CDC, I like it a lot. I crossed it at 1800 Hz LR4 and harmonic distortion was not a problem, subjectively it sounded really great... but I was attenuated by 22 dB at 1000 Hz.
j.
I think that should be enough, especially as this tweeter has almost no distortion there as Troels measured. The CDC i never saw measurements of, but for most tweeters i would not do that as the distortion in that region is way to high. I think the SB26ADC is the cleanest tweeter i know down that low.
I don't think those scanspeak D3404/552000 mentioned are better (more expensive is not always better). At least not on published specs or tests i saw. That one i would only use above 2kHz, probally even only above 2.5Khz due to the distortion. And the price of a pair is like my whole budget for this project. I also need a woofer and crossover parts and wood and so... 😉
The volt is a good woofer, but above budget for this. But for the rest a good suggestion. I did look at it.
I don't think those scanspeak D3404/552000 mentioned are better (more expensive is not always better). At least not on published specs or tests i saw. That one i would only use above 2kHz, probally even only above 2.5Khz due to the distortion. And the price of a pair is like my whole budget for this project. I also need a woofer and crossover parts and wood and so... 😉
The volt is a good woofer, but above budget for this. But for the rest a good suggestion. I did look at it.
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I actually going to look at a higher order crossover also today with the graphs i have now. When overthinking this it may be a feasable thing to go higher for a speaker of this. I in general don't like steep slope crossovers, but for a monitor like speaker personal preference should not be an big argument i think. I should at least look at that. But the proof of the pudding is the eating they say, so the final crossover will be on measurements (and also listening, but mainly measurements) when i build the cabinet anyway...