You say the smallest spare resistors you have on hand are 6 ohms? Try adding two of those in parallel to your "3.6", then listen...
Remember many speakers such as B&W at the store are too "hot" and it may take a little while to get used to a more natural sounding speaker
EDIT: sorry, yes, I meant to put "1011" not "1051" earlier...
What we are suggesting will lower the value to about 1.7 or so, if you lower "1011" to ~ 1 Ohm you should get at least a 2 db boost over your current setup w/the 3.6 Ohms resistor you have now.
Remember many speakers such as B&W at the store are too "hot" and it may take a little while to get used to a more natural sounding speaker
EDIT: sorry, yes, I meant to put "1011" not "1051" earlier...
What we are suggesting will lower the value to about 1.7 or so, if you lower "1011" to ~ 1 Ohm you should get at least a 2 db boost over your current setup w/the 3.6 Ohms resistor you have now.
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thanks guys for the massive reply.
first: for me myself i use a twisted pair cat5 cable (well cable is not the approriate word, cause it is more like a thin wire. i'm happy with it. my amp can only deliver 10 watts; plenty for me.
well me myself have never liked the b&w sound, and since my budget isn't that big, the only speakers i have are fullrangers, except the fonken 127, the fostex 167 and coral 8 do not produce that very bright sound , so i like it a lot
anyway, i'll try it immediatly. to exited not too.
thanks guys
i think that the tweeter xt25 is indeed very smooth, but i assure you, there are already 3 guys who think that the tweeter is a bit to low in volume. so i'm gonna try to put some resistor in parrallel and see what happens.
first: for me myself i use a twisted pair cat5 cable (well cable is not the approriate word, cause it is more like a thin wire. i'm happy with it. my amp can only deliver 10 watts; plenty for me.
well me myself have never liked the b&w sound, and since my budget isn't that big, the only speakers i have are fullrangers, except the fonken 127, the fostex 167 and coral 8 do not produce that very bright sound , so i like it a lot
anyway, i'll try it immediatly. to exited not too.
thanks guys
i think that the tweeter xt25 is indeed very smooth, but i assure you, there are already 3 guys who think that the tweeter is a bit to low in volume. so i'm gonna try to put some resistor in parrallel and see what happens.
i made some adjustments,
i soldered two wires (cat5) in parrallel with the resitor, pushed the wires out of the reflex hole, and now i can connect anything i want.
i have measured the original resistor and it was indeed 3.3 ohm (i guess i didn't pushed down the pins hard enough. i have put a 4.7 ohm parrallel, so i get 2 ohm. you can hear it but it is not a world of difference, maybe enough. i have connecte a 0.8 ohm extra parralel to it, making a total of 0.5 ohm and that is to bright, it remembers me of my fonken fe127. i'm gonna start listen to it with the 4.7 ohm,; i have also a 3.3 lying around, so i'll keep you updated, but this can take a week or so.
thanks guys
been listening to the 3.3+4.7 and i think it might even be a tad to bright. but you can hear the very nice integration. so that's super. tomorrow i'll repace the 4.7 with something bigger;
i soldered two wires (cat5) in parrallel with the resitor, pushed the wires out of the reflex hole, and now i can connect anything i want.
i have measured the original resistor and it was indeed 3.3 ohm (i guess i didn't pushed down the pins hard enough. i have put a 4.7 ohm parrallel, so i get 2 ohm. you can hear it but it is not a world of difference, maybe enough. i have connecte a 0.8 ohm extra parralel to it, making a total of 0.5 ohm and that is to bright, it remembers me of my fonken fe127. i'm gonna start listen to it with the 4.7 ohm,; i have also a 3.3 lying around, so i'll keep you updated, but this can take a week or so.
thanks guys
been listening to the 3.3+4.7 and i think it might even be a tad to bright. but you can hear the very nice integration. so that's super. tomorrow i'll repace the 4.7 with something bigger;
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well i'm back, but not really a solution.
i have tried a lot but never a satisfying result.
in the standard version, i like the lows and i like the higs. that is not the problem, but the woofer sounds very dull, i thought it was by the lack of highs, but after trying all kinds of resistors, even no resistor, i never got the sound right, now i have 0.82 resistor is serie with the woofer and that doesn't cut it either. I guess the woofer has to set in, that can be the only explanation i got. cause at this time the speaker is quite dreadfull.
i gotta run it in. a day of 20-100hz sweeps will do the trick i guess.
thanks
i have tried a lot but never a satisfying result.
in the standard version, i like the lows and i like the higs. that is not the problem, but the woofer sounds very dull, i thought it was by the lack of highs, but after trying all kinds of resistors, even no resistor, i never got the sound right, now i have 0.82 resistor is serie with the woofer and that doesn't cut it either. I guess the woofer has to set in, that can be the only explanation i got. cause at this time the speaker is quite dreadfull.
i gotta run it in. a day of 20-100hz sweeps will do the trick i guess.
thanks
i wanted to edit my post, but it seems that you can only do that 30min later that the post.
anyway: what i wanted to report is: i couldn't believe the dull sound the speaker produces, just right out of the box. i looked at evertyhing and it seemed that the port doesn't have the right dimensions, it is 3.8cm wide in stead of 4 and 9cm long in stead of 7. I have cut the port and the speakers sounds much better. i will buy a decent port and let it run in for 200h.
Sorry guys for the post, but since i didn't build the speaker i thought that the build would be good. not so...
thanks
greetz
anyway: what i wanted to report is: i couldn't believe the dull sound the speaker produces, just right out of the box. i looked at evertyhing and it seemed that the port doesn't have the right dimensions, it is 3.8cm wide in stead of 4 and 9cm long in stead of 7. I have cut the port and the speakers sounds much better. i will buy a decent port and let it run in for 200h.
Sorry guys for the post, but since i didn't build the speaker i thought that the build would be good. not so...
thanks
greetz
since i can't find any ports with the right inner diameter.
i looked around on the net, and found some nice port calculators.
when i look at troels page, i see that he designs the port for 55-60hz, and the fs of the driver is 56hz.
when you put in the data in the calculator, 7cm long, 4cm inner diameter, you are closer to 70hz tuning port. maybe my pair of peerless 830860 have an fs that is higher then 56hz and that resort in some serious boominess.
oh yes, the site: http://www.mh-audio.nl/PortLength.asp
voila
i looked around on the net, and found some nice port calculators.
when i look at troels page, i see that he designs the port for 55-60hz, and the fs of the driver is 56hz.
when you put in the data in the calculator, 7cm long, 4cm inner diameter, you are closer to 70hz tuning port. maybe my pair of peerless 830860 have an fs that is higher then 56hz and that resort in some serious boominess.
oh yes, the site: http://www.mh-audio.nl/PortLength.asp
voila
It is quite difficult because to describe things you use a language used by audiophiles, while actually you may mean different things. This is what you need to know:
1) Your 3 other drivers are fullrange, they are indeed sound different than this speaker. Two resistors 3.3 + 4.7 ohm in series with the tweeter really ROB the sensitivity of the tweeter (not my recommendation). This is a speaker for high power solid state amp, not 10 watt amp like yours. Your 10-Watt amp may have not low enough output impedance and the sound will usually became dull, lifeless.
2) You can reduce the series resistance (the 3.3 and 4.7) to get more treble. But that will usually change the design and the sound should become even worse! If you change the resistors in the tweeter network, you usually will have to also change the woofer network.
3) No "setting-in" required from the woofer. It sounds bad because of bad crossover. And your other systems (such as amplifier) might not be able to help, or simply not suitable.
4) Ups. I'm 100% sure that the dull sound come from the notch on the woofer
thanks jay
but the 3.3 and the 4.7 are in parrallel , so i get 2 ohm. i even played with a short circuit on the 3.3 resistor;
my amp is a tripath ta2020 (heavy modded) and plays quite well with the other fullrangers, much bigger coils, a lot of bass and with good control.
i have looked a bit further, and saw that my friend build the box a little bit bigger: 8.6L and with some felt in it; from troels site: felt adds 6% to the volume: 9.3 liter. when i calculate the original port length that was in there it was right at 56hz, so on the FS; now the tuning is at 62hz, and all is good. sometimes 1.5cm port lengt makes all the difference.
but the 3.3 and the 4.7 are in parrallel , so i get 2 ohm. i even played with a short circuit on the 3.3 resistor;
my amp is a tripath ta2020 (heavy modded) and plays quite well with the other fullrangers, much bigger coils, a lot of bass and with good control.
i have looked a bit further, and saw that my friend build the box a little bit bigger: 8.6L and with some felt in it; from troels site: felt adds 6% to the volume: 9.3 liter. when i calculate the original port length that was in there it was right at 56hz, so on the FS; now the tuning is at 62hz, and all is good. sometimes 1.5cm port lengt makes all the difference.
Well of course, it can make the whole thing up side down
The original design does have 3.3 and 4.7 in series with the tweeter. This takes away too many sensitivity out of the tweeter.
The original design uses notch filter around 800-900Hz on the woofer. This kills the woofer dynamics (make it sound dull and lifeless).
No I haven't built the speaker. But those 2 points I made are true. Resistor in series with the tweeter will kill the tweeter dynamic. Putting one in front of the filter is a good idea. The other one near the tweeter is dictated by the design (usually to match with the woofer). If the second resistor cannot be avoided, usually it can still be put before the second capacitor. But this is not important
There are two ways to avoid the dynamics-killer notch filter on the woofer.
1) First, you add more filter. So become 3rd order, with first filter (inductor) be big enough to pull down the response around 800-900Hz.
2) IF the effect of resonance/peak cannot be tamed with the first approach, there is a way to make a "smart" notch filter. But I'm not going to discuss this one.
I can make a working 3-way speaker using drivers with NO data at all, only by listening, because I know what happen when I increase or reduce component values.
I can give you a hint how to modify the crossover, but the problem is you have to tweak and listen it by yourself
In the above crossover:
1) I have removed 4.7 ohm in series with the tweeter. This will elevate the treble response. This is what you want. The 0.27 inductor has been changed to 0.24. This will reduce the peak/resonance from the tweeter.
2) I have removed the notch filter from the woofer. This will improve the dynamics of the woofer, close to dynamic quality of a fullrange driver. This is also what you want.
3) These mods should not change the overall group delay. Of course you need to tweak it to get precise similar performance. But it is close. If you can rely on your ears, you can find it.
1) I have removed 4.7 ohm in series with the tweeter. This will elevate the treble response. This is what you want. The 0.27 inductor has been changed to 0.24. This will reduce the peak/resonance from the tweeter.
2) I have removed the notch filter from the woofer. This will improve the dynamics of the woofer, close to dynamic quality of a fullrange driver. This is also what you want.
3) These mods should not change the overall group delay. Of course you need to tweak it to get precise similar performance. But it is close. If you can rely on your ears, you can find it.
thanks jay,
i was already reading about filters, i used to be able to calculate some standard things, so i need to pick it up again. any advice on a good book ?
second: thanks for the scheme. i'm looking at it right now.
i'm in need of some confirmation
troels design
the tweeter is a 3rd order filter
the woofer is a 2nd order filter with a band or notch filter:
thanks i see that you tried to develop a filter which could be easily build with the parts i have. i guess you are trying to get the resistors out of serie with the speaker., also like you said, you are making it into a 3rd filter for the woofer.
what is actually the crossover frequency ?
thanks a lot
greetz
ps: this mod is gonna take some time, i'm gonna ask my friend if he is willing to mod his driver, cause he glued everything in, i might to trash his speaker, or connect everthing with long wires...
keep you update
thanks
i was already reading about filters, i used to be able to calculate some standard things, so i need to pick it up again. any advice on a good book ?
second: thanks for the scheme. i'm looking at it right now.
i'm in need of some confirmation
troels design
the tweeter is a 3rd order filter
the woofer is a 2nd order filter with a band or notch filter:
thanks i see that you tried to develop a filter which could be easily build with the parts i have. i guess you are trying to get the resistors out of serie with the speaker., also like you said, you are making it into a 3rd filter for the woofer.
what is actually the crossover frequency ?
thanks a lot
greetz
ps: this mod is gonna take some time, i'm gonna ask my friend if he is willing to mod his driver, cause he glued everything in, i might to trash his speaker, or connect everthing with long wires...
keep you update
thanks
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when drivers are mounted flat on the baffle with no tweeter offset, its often done that way to get some delay on the tweeter
well, you could try to just leave out the zobel on woofer, and keep the notch filter
not that I like notches either
or just try and adjust the zobel
then you might get away with 12db on tweeter
I never needed more than 12db on the XT25, with tweeter offset
but its very 'sensitive' to changes
especially the resistor value in series with paralel inductor is exstemely important to get right
mind you, such small woofers have little lowend, and with more midrange it might sound very thin
and if you are using subs much of this may be different
not that I like notches either
or just try and adjust the zobel
then you might get away with 12db on tweeter
I never needed more than 12db on the XT25, with tweeter offset
but its very 'sensitive' to changes
especially the resistor value in series with paralel inductor is exstemely important to get right
mind you, such small woofers have little lowend, and with more midrange it might sound very thin
and if you are using subs much of this may be different
thanks tinitus.
my friend is not gonna use subs, but he will hang them in a corner on the ceiling, so i guess there is gonna be a hughe bump in the lows. not something what i like, (bumping the lows by cornering the speakers);
i need to know more myself, i have already downloade spice, (i worked with it years ago)
but a good book would be great.
indeed the small woofers don't bring big bass, but the boominess is gone with the correct port. i'm just curious what is gonna happen with jay scheme.
the 2 vs 3 order question: i guess you don't like 3 or 18db because of the sharp decay and rise of the drivers ?
thanks
my friend is not gonna use subs, but he will hang them in a corner on the ceiling, so i guess there is gonna be a hughe bump in the lows. not something what i like, (bumping the lows by cornering the speakers);
i need to know more myself, i have already downloade spice, (i worked with it years ago)
but a good book would be great.
indeed the small woofers don't bring big bass, but the boominess is gone with the correct port. i'm just curious what is gonna happen with jay scheme.
the 2 vs 3 order question: i guess you don't like 3 or 18db because of the sharp decay and rise of the drivers ?
thanks
What matters is the acoustical slope, not electrical. Driver natural roll-off might be first order in nature. So when you cross the driver near its natural roll-off, you need only 2nd order of electrical slope to get 3rd order of acoustical slope.
No you cannot. Midwoofers like this have peak before roll-off at around 4-5kHz. The "zobel" is the second low pass filter. Without this, the peak around 4-5kHz cannot be tamed. Unless you create a new zobel around that frequency. Not the one at 800-900Hz
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