3-way - Tower Speaker Project with Seas Drivers

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#61
You could consider this series cross over. Especially if you don't intend to measure/simulate. You can't biwire etc., but crossover points tracks each other, and tweaking is quite easy (sorry it's in danish but I think you can understand anyway)

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#62
Kjeldsen said:
You could consider this series cross over. Especially if you don't intend to
measure/simulate. You can't biwire etc., but crossover points tracks each
other, and tweaking is quite easy (sorry it's in danish but I think you can
understand anyway)
Click to expand...


Hi,

That's dragging out something from the past. Its a 2.5 way not
a 3 way and it is not suitable for a 10" bass and 5" midrange.

rgds, sreten.
 
#64
no technicalitys at the moment. this is just a small update,
i have got my drivers and put them in test boxes for playing with. im having great fun just playing threw music and film figuring out little bits here and there about stuff, and some stuff you lot where saying.

i have to say even with my unknown 3way crossover these speakers sound fantastic as they are, so i will probubly use these in the initiul phase, while i work out other bits in my mind.

you are all right about alot of things, especially how small things are noticable. for example lining up all three cones in 3d space seems to match the drivers better. shame i carnt get all the sound comming from one point, oh well, i prefur 3 points whole spectrum over 1 point middle spectrum, anyday

i also have observed that for a balanced sound that doesnt tinker at the top i need to somehow atttuette the tweeter by 4-8db depending on varying factors, still not quite sure, with the drivers allinied so the start of there radiating area's(dustcaps and tw cone) aline,... i feel 6 db sound about perfect.

in an ideal world i would like to somehow have a varying volume for each of the 3 drivers, which brings me onto the topic of active crossovers

tell you what though, im hearing sounds that usally hide bettween drivers, like the rising modulation of vocals

i do not at all regret priotising the vocal/emotional range with a wide range mid, in my opinion even now this speaker sounds better than these ones with 8/6inch woofers at single twetters, (mtm), i find that w/e the price they muddy up as soon as the bass radiator moves to much, making them all regardless of price sound like junk in the mid rage at half decent volume levels. but thats just my opinion.

i will keep you updated on the building process, all i can say now is im relying on my feeling and going for a lower tuned box, just hope it doesnt run out of steam to fast in this alinement,

carnt wait to hear these, and then hear them again later with a proper deviding network. even now they overlap well, maybe im just lucky.. cos i tryed other random woofer/ tweeters with different crossovers and there was a definate Ho le in the s ound

so the atual drivers on baffle will look kinda like this

-----|>tweeter
----|>mid
---|>woofer

(left to right) this seems to make the waves fit in-to eachother better (waveform/front)(think u guys call it phase of summin)

im using 25mm mdf, cos 18 vibrates to much, and i carnt b bothered to cut complex braces when thicker wood with less braces will work just as well.

i have decided to use 12mm / 50mm or summin bolts for the feet instead of floor spikes. because these are cheeper and will work just as well....
 
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#65
after further listening and not factoring the proper crossover, i have found the sound is far more complete sounding with a larger baffle. imagane a church arch shape with tweeter at the top mid just down and woofer firther down, the current test baffle is 50cm wide on the horizontal to the mid, this is just a concept and the shape of the baffle probubly isnt too importent, its just the mid seemed to not fit to well, and with a larger baffle the sound fieald between all drivers sounds whole, where as with a narrow baffle it didnt

i think a wider baffle sounds this mid unit better than a narrow one so i will be going with the current design just with a oversised baffle in nice ply that fits over the rest, (like a 3 piece puzzle)


jpg upload

any views on this will be appreciated,

the baffle will simply be like a removable face plate, and i can play with different shapes and sizes
 
#66
here is a visual example.
i put the woofer in a 100ish liter sealed cab made of celotaping 2 old speaker boxes together and hacking a hole in the front. its full of leaks...

mid is in a box, baffle is card and other junk just to get a feel for the changes

all i can say is a wider bafle fills the space in the room better, and sounds more real somehow


image upload

🙂
 
#68
thanks! its a good job i dont have to factor in WAF atm

it should work like this. build speaker first find girl second, that way she carnt have a issue😀

its fun stuff though, for example try playing a 60hz tone really loud, u can mess it about with your voice and walk around and hear it comming in and out of phase, fasinating stuff

regarding the paint pic i just posted, immagine dragging the front 2 corners and moving them neerer, and then pinching the top, you would end up with a kinda horn that changed size dependent on each driver. that would be great fun if i had some way to do it.....

but i dont, and wouldnt know how to begin simulating such a far out design. so i will stick to working on 2 dimentions
 
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#72
Kjeldsen said:
The baffle dont really add gain, only horn moutning wil add gain. But center placement will add som fluctuations in the frequency response, so linear tweeter suddenly will look anything but linear. So for tweeter and midrange the optimal placement is off center (no distance to sides should be equal)

The baffle width is the key element, and also placement of woofer. The narrower the baffle the higher the frequency where baffle loss begins. Typically you will begin to have a loss around 300 Hz. Passively you can only compensate by losing some efficiency above 300 Hz. So your 90,5 dB woofer will now be a 87 dB woofer or even lower.

You can also compensate by making the baffle wider or place the woofer close to the floor. Any reflector (floor and walls) will give you a 3 dB gain. Tha's why a woofer in the corner will have modt output.

A fully compensated woofer will sound boomy in the corner, but a non compensated woofer will sound fine.

You could also add another woofer to compensate for the baffle loss. You now have e 3½ way system since both woofer plays lowest freq's but only one play up to the midrange.
Click to expand...

Think there are some very interesting comments in this post, but trying to make sure I have interpreted their meaning correctly.

“But center placement will add some fluctuations in the frequency response, so linear tweeter suddenly will look anything but linear. So for tweeter and midrange the optimal placement is off center (no distance to sides should be equal)”

So if you had MTM would you keep them all vertically in line but shift them off centre of the baffle?

“The baffle width is the key element, and also placement of woofer. The narrower the baffle the higher the frequency where baffle loss begins.”

This seems to be a two edge sword… keep the baffle narrow and get less BSC, but increase echo from comb filtering (echo from the back wall)… Go wide and it appears to give better sound projection, but then face potential SPL drop off.

Currently building a new set of speakers myself and was wondering how wide to make the baffle… very interesting.
 
#74
Already have the design nearly finalised but I could easily make the top cabinet wider to equal the width at the bottom cabinet, without adding very much volume to a closed cabinet if there is an advantage to going wider.

While researching the Raal tweeters I came across this website that uses a flat baffle to mount the tweeter and wondered why he chose such a wide baffle...

Edit:
More recent version with centre section more rigid and reduced volume...
 

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#75
Silent Screamer said:
This seems to be a two edge sword… keep the baffle narrow and get less BSC, but increase echo from comb filtering (echo from the back wall)… Go wide and it appears to give better sound projection, but then face potential SPL drop off.
Click to expand...


No not correct. Since the narrow baffle have e BSC that should begin at higher frequency that a wider baffle. The loss from the BSC is more that from the wide baffle. A wide baffle will eliminate the need for BSC, and therefore give more SPL.

Thw downside of the wide baffle is that you will have more direct reflecting sound from the baffle, but that is mostly a problem in high midrange and tweeter and can be eliminated with proper use of felt (if you feel it's a problem).
 
#76
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#77
Kjeldsen said:
No not correct. Since the narrow baffle have e BSC that should begin at higher frequency that a wider baffle. The loss from the BSC is more that from the wide baffle. A wide baffle will eliminate the need for BSC, and therefore give more SPL.

Thw downside of the wide baffle is that you will have more direct reflecting sound from the baffle, but that is mostly a problem in high midrange and tweeter and can be eliminated with proper use of felt (if you feel it's a problem).
Click to expand...

Still sounds like a two edge sword to me... maybe not the same one as I said, but a compromise either way 🙂

So what would be your suggestion for mid and tweeter be... wide or narrow baffle?
 
#79
Ok I was going to ask if you meant to offset the drivers for the sound or the cabinet. I was almost envisaging something like this...
Offset in the cabinet but still horizontally lined up.

So what are you are trying to achieve by offsetting the drivers???

1) To help distribute sound reflection inside the cabinet, by causing uneven pressure waves?
or
2) Helping break up a linear sound from the driver output?

Guessing from the examples you just posted number 2???
 

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