Well, a lot of people mistake the first order harmonic (here 100Hz) for the fundamental, when regarding low frequencies. Our ears work that way and a lot of speaker systems really distort at low frequencies, producing those first order harmonics…
I made this one that uses Dayton ND91-4. You can get 55Hz-60Hz from it - but it's ported. Size is 12cm x 12cm x 20cm.
I did test sealed with some EQ to get the same bass extension. The ported had much lower distortion, it was very audible. I tried to keep the port area as large as possible.
![DSC_0172[1].jpg](https://www.diyaudio.com/community/attachments/dsc_0172-1-jpg.1051468/ "DSC_0172[1].jpg")
![LBMII+DSP+Outside[1].png](https://www.diyaudio.com/community/attachments/lbmii-dsp-outside-1-png.1051469/ "LBMII+DSP+Outside[1].png")
This version has some DSP with about +4dB in the low end and a cut below that. But you could get close with passive, especially if the cabinet were a little bigger.
I did test sealed with some EQ to get the same bass extension. The ported had much lower distortion, it was very audible. I tried to keep the port area as large as possible.
This version has some DSP with about +4dB in the low end and a cut below that. But you could get close with passive, especially if the cabinet were a little bigger.
Many people have praised this simple, inexpensive, elegant (series crossover!) two-way.
https://www.diyaudio.com/community/threads/diy-2-way-with-4-woofer-needed.375444/post-6751157
https://www.diyaudio.com/community/threads/diy-2-way-with-4-woofer-needed.375444/post-6751157
Eh, crossovers are bst tailored in situ, speaker built first, measured, measurements into simulator and of we go. Plenty of topics for that from search Same procedure for both active and dsp.
I'm not interested in any one else’s designs, they have their taste I have mine, I would never push my own taste onto someone else. I went thru diy once with a bass guitar, bought sold many of them, some were very high-end modern, some were vintage, could never find one I liked but did learn lot on how does wood, construction, pick up design and placement effects tone.
When I built my own with a help of local wood shop, it was perfect, just the right shape, weight, sound.... I spend 6 months looking for specific wood with specific grain orientation, did not compromise on anything.
Part of it is luck you still don't know how it will turn out with natural wood, but part of it is knowledge in knowing what type of sound you can get from different specs.
At that time I did not need a forum, I learned by paying money, today I can’t do that, plus with speakers it's not the same, we are stuck with the drivers we have on the market, and listening to commercial desktop stuff is useless, they make decisions based on accounting and production manger input not based on their sound engineers.
I come from studio speaker world, their approach to sound and business decisions is different, more risky with active systems, you sink or swim with those decisions very quickly, so comparing it to Hi-Fi desktop stuff is not the same, it’s not better but it’s different.
Slowly active studio monitors are getting smaller and smaller each year, not there yet, but in 5 years we will get there on some type of 3" MTM or array design from well established brands. They do not care about aesthetics among studio industry so we’ll never see a compromise of sound vs. aesthetics.
So at this stage please stop wasting bandwidth with driver or kit suggestions, it does not fit my criteria at all.
Cheers.
When I built my own with a help of local wood shop, it was perfect, just the right shape, weight, sound.... I spend 6 months looking for specific wood with specific grain orientation, did not compromise on anything.
Part of it is luck you still don't know how it will turn out with natural wood, but part of it is knowledge in knowing what type of sound you can get from different specs.
At that time I did not need a forum, I learned by paying money, today I can’t do that, plus with speakers it's not the same, we are stuck with the drivers we have on the market, and listening to commercial desktop stuff is useless, they make decisions based on accounting and production manger input not based on their sound engineers.
I come from studio speaker world, their approach to sound and business decisions is different, more risky with active systems, you sink or swim with those decisions very quickly, so comparing it to Hi-Fi desktop stuff is not the same, it’s not better but it’s different.
Slowly active studio monitors are getting smaller and smaller each year, not there yet, but in 5 years we will get there on some type of 3" MTM or array design from well established brands. They do not care about aesthetics among studio industry so we’ll never see a compromise of sound vs. aesthetics.
So at this stage please stop wasting bandwidth with driver or kit suggestions, it does not fit my criteria at all.
Cheers.
How do you want to learn if you don't want to get into technical details for a deeper understanding but also don't use knowledge of what already has been done?
Of course there is a third way - learning by doing it all on your own. Maybe not the worst method, but it takes time (and some money).
So, I encourage you to build your small two driver box and work on it. It can be very much fun and does not cost too much to start!
Of course there is a third way - learning by doing it all on your own. Maybe not the worst method, but it takes time (and some money).
So, I encourage you to build your small two driver box and work on it. It can be very much fun and does not cost too much to start!
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Is that comment for me? It looks like a lovely speaker!
It has design compromise like every speaker. In a very near field desktop speaker I choose driver integration over +6dB SPL.
It has design compromise like every speaker. In a very near field desktop speaker I choose driver integration over +6dB SPL.
That’s too bad, because many of these other designs have been done by people who have the knowledge and experience to create small speakers with great performance at very reasonable costs.
You have neither the knowledge nor experience, but think that somehow you can get the necessary advice, or perhaps hire someone, to create a design that defies the generally accepted principles of good speaker design. All because you arbitrarily have decided that a 3 inch woofer, or perhaps two of them, can deliver the low end you want without requiring any compromise to the overall sound performance.
And now you have predicted that if you don’t do it someone else within 5 years will. Considering your freely admitted lack of experience in speaker design, that is quite a bold statement. But please don’t be offended if many here discount your prediction as being entirely meaningless. You aren’t the first one to come to this forum and present ideas for speakers that are far off the well proven path for success.
That is a darn good suggestion.
I was going to suggest:
https://www.devialet.com/en-us/phantom-speaker/phantom-ii/
It is not an MTM but it is small.
...
If the OP wants to go the DIY route: Get some pink foam and a small box from parts express. Put the 3" woofers in that and give it a test. Foam test boxes are great to explore ideas before dropping tons of bucks. I use masking tape to seal the inside of the box and tape the outside. No glue is needed.
Listening in mono can answer many questions plus save the cost of buying 4 drivers. I find mono more critical than stereo.
Ok,
First of all I’m not offended by anyone’s comments, so please critic as much as you like, I like it, the more critique the better… pro athletes do not get better by encouragement they get better by critiquing their existing performance.
I do not want to learn to the extent that you want me to learn; if I did this forum would not exist.
Every forum on this planet on any subject matter has only two objective, one is to show off what you can do better then your fellow man, the other is for people like me with no time on their hands to learn, we come in ask questions and you solve it for us. You solve it with least amount of technical lingo and you get a rush out of it helping you fellow man.
I do the same on different forum on different subject matter if or when I have the time.
Learning via trial and error makes this forum absolute to leave it only to those that want to show off and that’s it, why would I need a forum at all if I can experiment on my own and learn slowly. I want to get to finish line fast, the same way if I go to a dentist I don’t want to learn how to do ra oot canal, he does it for me and within short time frame.
So far the only solution I got is I need to raise the low end by 20db to get what I want based on my uncompromising criteria.
Ok, next question was, what is the cleanest way to do that, either cut everything to lowest point then raise as a whole or raise the low end only.
Do I raise the low end at a fixed frequency of 50hz, or a range from 50 to 120hz?
Do I raise it via Tri-amp with more wattage on one of the drivers till it’s x-max pops off or burn the coil that will be crossed at 120hz by 6db or 12db slope, or do I raise it with a tone control, which might be the same thing.
Is there a difference in how to raise the low it sonic quality, or is it all the same, voltage is voltage no matter how you do it.
Maybe I need to move this into an Amp section to find the answers, so I’ll wait to see if anyone can answer these here, if not I’ll move on to another section.
Cheers
First of all I’m not offended by anyone’s comments, so please critic as much as you like, I like it, the more critique the better… pro athletes do not get better by encouragement they get better by critiquing their existing performance.
I do not want to learn to the extent that you want me to learn; if I did this forum would not exist.
Every forum on this planet on any subject matter has only two objective, one is to show off what you can do better then your fellow man, the other is for people like me with no time on their hands to learn, we come in ask questions and you solve it for us. You solve it with least amount of technical lingo and you get a rush out of it helping you fellow man.
I do the same on different forum on different subject matter if or when I have the time.
Learning via trial and error makes this forum absolute to leave it only to those that want to show off and that’s it, why would I need a forum at all if I can experiment on my own and learn slowly. I want to get to finish line fast, the same way if I go to a dentist I don’t want to learn how to do ra oot canal, he does it for me and within short time frame.
So far the only solution I got is I need to raise the low end by 20db to get what I want based on my uncompromising criteria.
Ok, next question was, what is the cleanest way to do that, either cut everything to lowest point then raise as a whole or raise the low end only.
Do I raise the low end at a fixed frequency of 50hz, or a range from 50 to 120hz?
Do I raise it via Tri-amp with more wattage on one of the drivers till it’s x-max pops off or burn the coil that will be crossed at 120hz by 6db or 12db slope, or do I raise it with a tone control, which might be the same thing.
Is there a difference in how to raise the low it sonic quality, or is it all the same, voltage is voltage no matter how you do it.
Maybe I need to move this into an Amp section to find the answers, so I’ll wait to see if anyone can answer these here, if not I’ll move on to another section.
Cheers
You're not getting answers that you like here because you keep ignoring the basic fact, which has been expressed by multiple people, that trying to get 50 Hz out of a 3-inch driver is going to result in excessive distortion regardless of how soft you run it.
If distortion is not an issue for you then go for it.
However, for most people that kind of distortion would send them off in a different direction to get a speaker that they are much more likely to enjoy.
And that direction would not include an MTM configuration for very close near field desktop listening. MTMs need distance to allow the sound fields from the multiple drivers to merge properly.
Bottom line: If you really want good sound at 50 Hz, then build speakers with larger drivers than 3 inch. Attempting to solve this problem by chasing amplifiers is not going to work, because it's not amplifier problem to begin with. It's a speaker driver size issue.
Ok, let try this as reference to establish what does 50hz sounds like and what db I can live with
This sound:
I can hear the bass up to about 110hz then it disappears, but the kick drum I can hear up to the end. Is this a frequency test or something else?
On this one:
I can hear it all of it, but it gets louder as it goes up in frequency first jump is around 85hz in loudness, then gets more loud, up to about 160hz then slight deep down then another jump, up at 190hz or so then another jump even higher at 210hz at 250hz another jump up
I suspect this is just octave by octave going up does that mean my speakers are not linear at all they simply start at one level of db. And progressively going up and up to 300hz.
Can we try this:
Can anyone with enough equipment take this sample?
Play it back at 70db, 75db and 80 db... record all three and upload, so I can hear how big of a drop is 5db. This will tell me some more info; maybe my target should be 70hz at 70 db vs. 50hz at 80db.
What confuses me is two drivers in parallel adding 6db, I can’t figure out how it would actually add to the low end. If we are limited by x-max on low end then even 5 x 3" drivers could never increase the db at 50hz, the surface area might increase but they are all still only moving by 2.5mm or so. Maybe looking at 2 drivers to gain 6db is a mistake and in real life it's not actually 6db, but slight bump of 1-2db.
Cheers.
This sound:
I can hear the bass up to about 110hz then it disappears, but the kick drum I can hear up to the end. Is this a frequency test or something else?
On this one:
I can hear it all of it, but it gets louder as it goes up in frequency first jump is around 85hz in loudness, then gets more loud, up to about 160hz then slight deep down then another jump, up at 190hz or so then another jump even higher at 210hz at 250hz another jump up
I suspect this is just octave by octave going up does that mean my speakers are not linear at all they simply start at one level of db. And progressively going up and up to 300hz.
Can we try this:
Can anyone with enough equipment take this sample?
Play it back at 70db, 75db and 80 db... record all three and upload, so I can hear how big of a drop is 5db. This will tell me some more info; maybe my target should be 70hz at 70 db vs. 50hz at 80db.
What confuses me is two drivers in parallel adding 6db, I can’t figure out how it would actually add to the low end. If we are limited by x-max on low end then even 5 x 3" drivers could never increase the db at 50hz, the surface area might increase but they are all still only moving by 2.5mm or so. Maybe looking at 2 drivers to gain 6db is a mistake and in real life it's not actually 6db, but slight bump of 1-2db.
Cheers.
Your mental model needs to include the performance of a mid in-room and your gain is on top of that.
Here is a graph for a 3" driver. Adding +6db to bass that is dropping like a brick is meaningless. There is no power. It is like taking a moped on the highway.
It is totally possible as I described:
https://www.diyaudio.com/community/...khz-is-it-possible.385751/page-2#post-7010253 and my next post
but it does depend on your room
DSP is the easiest way to do it
I used Dynamic EQ to make a Linkwitz transform (bass boost), the dynamic part is that above a set level, it doesn’t boost as much and compresses the bass. This stops the bass being so high that it sounds bad and damages the speaker. It can be done analogue too, but that would not be easy
Brian
https://www.diyaudio.com/community/...khz-is-it-possible.385751/page-2#post-7010253 and my next post
but it does depend on your room
DSP is the easiest way to do it
I used Dynamic EQ to make a Linkwitz transform (bass boost), the dynamic part is that above a set level, it doesn’t boost as much and compresses the bass. This stops the bass being so high that it sounds bad and damages the speaker. It can be done analogue too, but that would not be easy
Brian
With loudspeakers some learning is mandatory, you have to measure the box and be able to judge the measurements somehow in order to get anything close to enjoyable audio wise. We can answer some if not most of your questions but at some point you have to provide data for further quidance. Otherwise it is asking the community to make you a kit and there is no point vecause there are plenty already. You really should buy a kit or finished product. I mean there is no point build something without thinking at all, waste of time, there is nothing in it then as the end product would probably be less than the investment. Most of people do DIY because they want to learn stuff, this is the return for time and money invested even if the end product wasn't that good. Or to have fun, to make something. Perhaps there is something for you as well but currently it is hard to see what it is what you are after? Spend time and currency units for nothing? You've said you want it fast. DIY path can take years in some cases, pace of learning and how much you can invest your time for the hobby.
The aesthetics you strive for is actually one of the few benefits in DIY, you can make them speakers to look like what you want. But the audio performance will not pop up there without learning how to do it. I'm failing to see why not just build them as decorations, give them to a shop/friend to put some drivers and electronics in? This would ve fastest and cheapest and good outcome. If you want better than this you have to be open to learning how to actually do it.
I suggest just build what is it that you want to build, put a small subwoofer element and a good fullrange element in, separate compartments. Perhaps tweeter if you want. DSP crossover, because with DSP you can boost the bass and experiment with it. Even without measurements you can experiment with the crossover if the sound doesn't feel right.
This post is not to let you down on the project, quite the reverse. Take a deep breath, think what you are doing.
Tone controls are not usually something that can tailor bass response, they are more like wide brushess, shelving filters affecting multiple octaves, tone controls. DSP usually has all kinds of filters and tone controls can usually be emulated as well if you wish to experiment. Any kind of boost or gain eventually increases power output from amp and the driver vibrates more. It is the size and quality and number of drivers that first and foremost limits the performance. You absolutely have to do some research on this.