'Upgrading’ my tweeters (can I do this?)

AllenB

Moderator
Paid Member
2008-10-18 11:31 am
is this what you guys kinda do when designing a crossover?

choose drivers and then ‘ play ‘ with XSIM with component values that are reasonable ?
No, but it's a good exercise.
and to have the Impedance smooth?
No.
is that a really bad design cause the rolloffs are really shallow?
At this point see if you can get them even and complementary, like a LR filter. Enable phase for the separate ways and turn off system phase.
 

tone?

Member
2022-05-26 8:52 am
No, but it's a good exercise.

No.

At this point see if you can get them even and complementary, like a LR filter. Enable phase for the separate ways and turn off system phase.
Ok like this?

what do the phase dotted lines tell me for both the tweeter and drivers ?

thanks man. Pardon for all the questions


7698A41D-9EC9-4ECE-B4ED-A6A9085EC1ED.jpeg
 
Why are you switching to wattage specification? 2.83 volts is a whole lot easier to compare apples to apples.

With 2.83V the 4ohm tweeter is + 3dB more efficient than the same one with impedance of 8ohm. 2.83V is 1W at 8ohm and 2W at 4ohm. In order to realistically compare them in terms of efficiency, you reduce them all to 1W 1m. The power of the amplifier is declared in W at a certain impedance.
 
i thought the resistor doesn’t count as an order

The electrical order of the filter should be distinguished from the acoustic one. It is usually acoustically higher for the tweeter because the driver has its own slope. The final result is important, ie the acoustic slope obtained by summing the filter slope and the driver slope. The same is the case with the phase, the filter phase and the driver phase are added together.
 
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With 2.83V the 4ohm tweeter is + 3dB more efficient than the same one with impedance of 8ohm. 2.83V is 1W at 8ohm and 2W at 4ohm. In order to realistically compare them in terms of efficiency, you reduce them all to 1W 1m. The power of the amplifier is declared in W at a certain impedance.
With 2.83 volts as your input they are all rated at the same voltage. With the same output at the same voltage from the amplifier you have the variance right there in the Tweeter itself only. If you are comparing Apples to Apples you should measure at 2.83 volts and it doesn't matter what the impedance is because everything will be at the same voltage. Drivers are voltage sensitive devices, and watts don't mean diddley if you have to convert for impedance every time.

Please, just use 2.83vac and do it the easy way and save yourself some time.
 
With 2.83 volts as your input they are all rated at the same voltage. With the same output at the same voltage from the amplifier you have the variance right there in the Tweeter itself only. If you are comparing Apples to Apples you should measure at 2.83 volts and it doesn't matter what the impedance is because everything will be at the same voltage. Drivers are voltage sensitive devices, and watts don't mean diddley if you have to convert for impedance every time.

Please, just use 2.83vac and do it the easy way and save yourself some time.
I don't see what the problem is. Both ways of expressing sensitivity are relevant and easy to recalculate. You only need to pay attention to the impedance of the driver if the sensitivity is expressed by 2.83V / 1m. So that there are no wrong conclusions that a driver is more sensitive just because the impedance is lower.
 

tone?

Member
2022-05-26 8:52 am
No and no. It depends on which dispersion characteristic you want.

so obviously my speakers have a bit of a bbc dip most likely from now short they are

when the mic is placed lower the bbc dip goes away.

first pic is with the mic lower and the second is with the mic higher.

is there any way to compensate for that on the xo?

the one capacitor on the tweeter is 8uf
and on the woofer is 16uf

if I make them 10uf on the tweeter and 14uf on the woofer this will raise the dip a couple dbs I think. Off axis that is.

is this correct?


6D8FB7E2-6E91-48B1-8F88-2E0EE34B1909.png


EC6BF0BF-6851-477C-A6F7-E0259C96659E.png
 

tone?

Member
2022-05-26 8:52 am
yes.

if my listening distance was further away it would solve a lot.

right now my room sucks.
and my listening distance is only 8 feet

if I was back 3 more feet even it would be better.

if you start tiling the speakers back and raising the rake angle , things get a bit more ‘airy ‘
 
so obviously my speakers have a bit of a bbc dip most likely from now short they are

when the mic is placed lower the bbc dip goes away.

first pic is with the mic lower and the second is with the mic higher.

is there any way to compensate for that on the xo?

the one capacitor on the tweeter is 8uf
and on the woofer is 16uf

if I make them 10uf on the tweeter and 14uf on the woofer this will raise the dip a couple dbs I think. Off axis that is.

is this correct?
Any crossover setup will generate some form of vertical lobing. I'd have to sim the design to be able to predict the vertical polar response for this system. You could tilt the enclosures just a little bit backwards if the dip bothers you.
 
yes.

if my listening distance was further away it would solve a lot.

right now my room sucks.
and my listening distance is only 8 feet

if I was back 3 more feet even it would be better.

if you start tiling the speakers back and raising the rake angle , things get a bit more ‘airy ‘
your room acoustic suck...
but you want to add brace to your expensive commercial Proac speakers.

dont you think your car should at least have brakes before adding a turbo?
 
So you were try to dissuade me on my Bracing thread and now you jumped on to this thread of mine to do the same and continue to badger me.
lol

dude , are you ok?
concerned about you.

i don’t know , maybe you are just having a bad day.

hope all is well. Honestly.
your room acoustic is bad.
I think you would get 20 times better return in your investisment if you did work toward improving something that really, objectively speaking, makes tremendous measurable improvement

have fun with your spedometer and expensive tweeter! you will learn a thing or two.

as for me, couldnt be better: housing is unnafordable, lost my career due to covid. thx for asking :)
 
I don't see what the problem is. Both ways of expressing sensitivity are relevant and easy to recalculate. You only need to pay attention to the impedance of the driver if the sensitivity is expressed by 2.83V / 1m. So that there are no wrong conclusions that a driver is more sensitive just because the impedance is lower.
Expressing by wattage is not sensitivity but efficiency, and normally at a percentage. Efficiency is by wattage, sensitivity by voltage. You do not need to express the impedance when spec by voltage. You do at 1W or 2W as power varies into the load. At voltage, you get the output at the same voltage, no conversion necessary, and xover design is best done at voltage where no conversion needs to be done.

Efficiency does not take the doubling into account, so you only get +3dB as opposed to +6dB when using 2 drivers over one. If you mic-measure at one output level, and don't move the knob, then wattage will change with load difference whereas voltage remains consistent. You don't want to have to adjust for wattage in design on the fly, as it is changing.

If you have 2 drivers at 2.83V, and one is 89dB and the other is 91.5dB, you have 2.5dB delta. Plain and simple.

You are not the first person i've seen reference wattage over voltage, but it is just not as practical in use or during design of xovers with the way the drivers, amplifiers and microphones actually function.
 
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