What about impedance and buffers? I read somewhere (can't find it again) that the buffer is needed for the filters to work properly.
Depends on the relative impedance. A source impedance much less than
the RC values of the filter will give very close results. A sim will give you
a clear picture of what the variation will be.
Thanks for taking the time to answer. 🙂
Not sure I will be able to make a sim. I have been trying to grasp what Impedance really is for a long time without succeeding. Now you tell me there is something called Relative Impedance? It could just as well have been the Relativity Theory.
Without a sim, which of these suggestions for a passband make-over would you recommend for a noobie?
Not sure I will be able to make a sim. I have been trying to grasp what Impedance really is for a long time without succeeding. Now you tell me there is something called Relative Impedance? It could just as well have been the Relativity Theory.
Without a sim, which of these suggestions for a passband make-over would you recommend for a noobie?
Look at your typical resistor values in the filter elements - if the source resistance
(impedance) is much less than those, then were will be minimal influence.
(impedance) is much less than those, then were will be minimal influence.
Hey all,
Quickly filling a shopping cart, and just wondering if 250mW resistors are fine? The BOM lists mainly .4W resistors - but not everything is in stock.
Quickly filling a shopping cart, and just wondering if 250mW resistors are fine? The BOM lists mainly .4W resistors - but not everything is in stock.
🙂
Aaaaand ...
What about 16V electrolytics on the outputs instead of 25? Do these caps see the full 24V, or half of it?
Aaaaand ...
What about 16V electrolytics on the outputs instead of 25? Do these caps see the full 24V, or half of it?
I got caps from Mouser, Rs from Digikey. No issues with standard BOM. Delivery to Melbourne 3-5 days
Could someone with experience of the 6-24XO calculate the best values for a 24db @1300Hz 2-way crossover.
I am matching a Pro-Ribbon and the Purifi PTT6.5w04.
The ribbon goes down to 1300Hz.
At the moment I am using the stock passive crossover but both speakers are firing evenly at about 1250Hz.
Many thanks in advance if anyone can help.
I am matching a Pro-Ribbon and the Purifi PTT6.5w04.
The ribbon goes down to 1300Hz.
At the moment I am using the stock passive crossover but both speakers are firing evenly at about 1250Hz.
Many thanks in advance if anyone can help.
You should not go for an "electrical" calculation, you need to include the frequency response of the drivers as they sit in your speakers. To calculate the electrical response of your crossover you can use this: https://sound-au.com/software/esp-lr13.exe But it will not give a flat response of the speakers.
In what way are you going to use your active crossover?
Are you adding a subwoofer to an existing speaker?
Are you to replace a passive crossover in an existing speaker?
Are you doing a speaker from scratch?
First of all you need to have a target curve for your crossover. If you have no idea of that, it will be difficult. Even if you have a target, it will be more or less difficult.
I dont understand the step from having the frequency response as they
sit in my speakers, to calculating the electrical response of my crossover. How would you include all this when choosing the parts for this crossover?
sit in my speakers, to calculating the electrical response of my crossover. How would you include all this when choosing the parts for this crossover?
You measure the responses without a crossover. Will not look very nice in many cases. If you have a software for simulation, you can import the responses and play with various slopes. You also need to look for lobing and off-axis response. It will be some work.
In order to use this active crossover, just buy the components missing. What is your supposed crossover frequency.
In order to use this active crossover, just buy the components missing. What is your supposed crossover frequency.
"In what way are you going to use your active crossover?"
3-way + active sub with its own crossover, with two bandpasses at approx. 80-450, and 450-2000, and one highpass at 2000Hz. But the vintage bass guitar woofer JBL K140 15" are pretty much everywhere, so I may have to cross them lower or EQ the hell out of them.
"Are you adding a subwoofer to an existing speaker?" Yes, active with its own crossover.
"Are you to replace a passive crossover in an existing speaker?" Yes, mid and highs are divided now by a passive speaker level crossover. Then I divide sub, midwoofers and mid+hi with a minidsp.
"Are you doing a speaker from scratch?" No, the speakers have been more or less done for a while now.
"First of all you need to have a target curve for your crossover. If you have no idea of that, it will be difficult. Even if you have a target, it will be more or less difficult." I have done some trials with Dirac Live and I prefer scooped eq, if that is what you are referring. But as this crossover is highly adjustable and has no EQ, I don't see a reason to worry. I can maybe add an EQ later. I would have to play with this EQ andbadjustable crossover for several years more to find a good setting.
3-way + active sub with its own crossover, with two bandpasses at approx. 80-450, and 450-2000, and one highpass at 2000Hz. But the vintage bass guitar woofer JBL K140 15" are pretty much everywhere, so I may have to cross them lower or EQ the hell out of them.
"Are you adding a subwoofer to an existing speaker?" Yes, active with its own crossover.
"Are you to replace a passive crossover in an existing speaker?" Yes, mid and highs are divided now by a passive speaker level crossover. Then I divide sub, midwoofers and mid+hi with a minidsp.
"Are you doing a speaker from scratch?" No, the speakers have been more or less done for a while now.
"First of all you need to have a target curve for your crossover. If you have no idea of that, it will be difficult. Even if you have a target, it will be more or less difficult." I have done some trials with Dirac Live and I prefer scooped eq, if that is what you are referring. But as this crossover is highly adjustable and has no EQ, I don't see a reason to worry. I can maybe add an EQ later. I would have to play with this EQ andbadjustable crossover for several years more to find a good setting.
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"two bandpasses at approx. 80-450, and 450-2000, and one highpass at 2000Hz"
That will be quite a long signal chain. As you may need to tilt your curve for some of your drivers. You have not concidered a DSP doing it all?
What is your passive speaker level crossover looking like? Do you have a schematic?
That will be quite a long signal chain. As you may need to tilt your curve for some of your drivers. You have not concidered a DSP doing it all?
What is your passive speaker level crossover looking like? Do you have a schematic?