Hi Dirk
Was wondering about the capacitors you used.
Very nice job indeed!
Was wondering about the capacitors you used.
Very nice job indeed!
Thank you 😎 for this beautiful active crossover!!!
Dirk
to Eitan100 #761
Hello Eitan100,
you mean the white pp-caps? Those are Mundorf-caps.😉
Greets
Dirk
Hello Eitan100,
you mean the white pp-caps? Those are Mundorf-caps.😉
Greets
Dirk
I am just looking at their site, which kind are the best to use in this setting?
Thank you,
Eitan
Thank you,
Eitan
to Eitan100
Hello Eitan100,
I wouldn't worry too much about the caps. As lomg as they are from a well
reputated company.
I wanted to test the Mundorfs. It was their smallest value they offer (0,1µF).
It only made sense, because I have a crossover-frequency of 80Hz. So I needed a
pretty high µF - value.
In my other build of the 6-24XO I used WIMA-caps. They sound excellent.
Greets
Dirk
Hello Eitan100,
I wouldn't worry too much about the caps. As lomg as they are from a well
reputated company.
I wanted to test the Mundorfs. It was their smallest value they offer (0,1µF).
It only made sense, because I have a crossover-frequency of 80Hz. So I needed a
pretty high µF - value.
In my other build of the 6-24XO I used WIMA-caps. They sound excellent.
Greets
Dirk
Thanks Dirk, I was wondering about upgrading caps for my second build but seems wima is fine. Great build again btw😉
Hello everyone! I want to build Lxmini+2 system using 2 of these boards. Will it work? Is there a BOM for something like that?
PSU supply voltage
I’m partially through building a psu for this x-over similar to Dirks. I’m using an Antek AS-0515. 15v secondaries and using it with a eBay LT1084 rectifier/regulator. I’m only getting 20vdc out of it. Will this voltage work? NP’s write up only talks about not exceeding 30vdc.
I’m partially through building a psu for this x-over similar to Dirks. I’m using an Antek AS-0515. 15v secondaries and using it with a eBay LT1084 rectifier/regulator. I’m only getting 20vdc out of it. Will this voltage work? NP’s write up only talks about not exceeding 30vdc.
to TboneAK #769
Hello TboneAK,
if you have used a transformer with 15V AC secondaries, the n you will end up after rectifiers and crc- filter at around 15V AC x 1.3 = 19,5V DC.
This is to low to regulate it down to 24V DC.
You have dual secondaries at your 2 x 15 V - transformer. So, if you use both secondaries ( connected inline) you get 30 V AC out. After rectifier and filter
you would 'land' anywhere around 39 V DC. I think this is a too high inputvoltage for the LT1084/1085.
If I use only one of the secondaries at the output of the transformer, then I choose secondary voltages of (2x20 V AC) better 2x22V ac or 2x24V AC.
2x22V AC will give you around 28.6 V DC (after rectifier and CRC- filter).
Then your LT1084/1085 would have to regulate 4.6 V down to 24V DC.
The regulator has 'something to do' but not too much, that you need a big heatsink.
Greets
Dirk
Hello TboneAK,
if you have used a transformer with 15V AC secondaries, the n you will end up after rectifiers and crc- filter at around 15V AC x 1.3 = 19,5V DC.
This is to low to regulate it down to 24V DC.
You have dual secondaries at your 2 x 15 V - transformer. So, if you use both secondaries ( connected inline) you get 30 V AC out. After rectifier and filter
you would 'land' anywhere around 39 V DC. I think this is a too high inputvoltage for the LT1084/1085.
If I use only one of the secondaries at the output of the transformer, then I choose secondary voltages of (2x20 V AC) better 2x22V ac or 2x24V AC.
2x22V AC will give you around 28.6 V DC (after rectifier and CRC- filter).
Then your LT1084/1085 would have to regulate 4.6 V down to 24V DC.
The regulator has 'something to do' but not too much, that you need a big heatsink.
Greets
Dirk
Hi Dirk,
How do you come up with your 1.3 multiplication factor? Rod Elliot's pages mention 1.414 as the factor, but I have no idea of the conditions that affect this number.
Thanks,
Alan
How do you come up with your 1.3 multiplication factor? Rod Elliot's pages mention 1.414 as the factor, but I have no idea of the conditions that affect this number.
Thanks,
Alan
to aljordan
Hello aljordan,
that is my rule of thumb. I often use the factor 1.3 to 1.4.
I often got different DC-values then estimated. If you use a CRC-filter in front of the regulator, it also depends on your R-value.
Greets
Dirk
Hello aljordan,
that is my rule of thumb. I often use the factor 1.3 to 1.4.
I often got different DC-values then estimated. If you use a CRC-filter in front of the regulator, it also depends on your R-value.
Greets
Dirk
Remember, that is the voltage under load, check the voltage under small loads. What i the maximum input voltage to the LT1084/1085? I have not found it in the data sheet.
Thanks Dirk! It's all making sense now. I was thinking the regulator could boost the voltage. I did some more reading on the ebay boards I'm using and I think that I was worried if the supplies were to high I'd smoke stuff.
I swapped out the 2x15v with a 2x20v. I get 27.6v after the rectifiers. The LT1084 board output is now set at 24.1v, no load. So I think that will do it for the 6-24.
I'm using the other 20v output from the transfo to power a RPi/DAC. Ebay retifier board feeding a CapMX PSU with a TPS7A4000 regulator for 5v output. I didn't want the input voltage to high. I miss read the input limit as 20v. Looks like it will work. When I get it finished I'll post pics.
TPS7A4700 DC3~35V To DC1.4~20V Low Noise LDO Regulator RF Power Supply Module | eBay
Thanks as always for all the help!
Best Regards, Tbone
I swapped out the 2x15v with a 2x20v. I get 27.6v after the rectifiers. The LT1084 board output is now set at 24.1v, no load. So I think that will do it for the 6-24.
I'm using the other 20v output from the transfo to power a RPi/DAC. Ebay retifier board feeding a CapMX PSU with a TPS7A4000 regulator for 5v output. I didn't want the input voltage to high. I miss read the input limit as 20v. Looks like it will work. When I get it finished I'll post pics.
TPS7A4700 DC3~35V To DC1.4~20V Low Noise LDO Regulator RF Power Supply Module | eBay
Thanks as always for all the help!
Best Regards, Tbone
to TboneAK #774
Hello Tbone,
sounds good! You can measure the outputvoltage of your PSU if the 6-24XO is
hangin' on it.
Enjoy the sound of your 6-24XO!
Cheers
Dirk
Hello Tbone,
sounds good! You can measure the outputvoltage of your PSU if the 6-24XO is
hangin' on it.
Enjoy the sound of your 6-24XO!
Cheers
Dirk
The board is pretty tolerant of voltage range, although it should not exceed voltages
of power supply filter caps or about 30V, whichever is lowest...
of power supply filter caps or about 30V, whichever is lowest...
Did you use the unit with a wall wart or laptop supply previousy....? If so...how much is gained ?? I'm running out of projects ....
Beyond all hope... it actually works! And not only does it work, it's magic. It managed to transform the cheapest speakers I own, a pair of Sony bookshelf speakers, into some very respectable sounding speakers. I was amazed. Now the existing crossover in the speaker consisted of a single very small cap on the tweeter, so this was a big change in components. But the change in sound is quite dramatic. Thanks Mr. Pass!
I am now going to buy another board and expand mine to a three-way system. I may attempt to use it with an LX-521 build. I'll move the PS externally and the second board will fit on the right side. I already have the output jacks for the woofer output. And who knows. Maybe I'll go crazy and put an off-on switch on it somewhere too.
I am now going to buy another board and expand mine to a three-way system. I may attempt to use it with an LX-521 build. I'll move the PS externally and the second board will fit on the right side. I already have the output jacks for the woofer output. And who knows. Maybe I'll go crazy and put an off-on switch on it somewhere too.
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Congrats on the build!
I would not be able to resist the tempation to move the PSU as far away in the box from the x-over as possible though, to minimize the risk of inducing extra switching noise into the board.
I just finished a set of mini's so the LXmini boards I had bought for my other OB project(s) are now in progress of being assembled in the standard configuration, I did not see that coming when I bought the boards.
The mini's are such a nice and easy build they just slipped in in the end of my LX521.4 build - which has also been quite a long journey...
Interesting thought to use the 6-24 boards for LX-Mini +2's - or even LX521.4
Any thoughts and updates on that would be highly appreciated
I would not be able to resist the tempation to move the PSU as far away in the box from the x-over as possible though, to minimize the risk of inducing extra switching noise into the board.
I just finished a set of mini's so the LXmini boards I had bought for my other OB project(s) are now in progress of being assembled in the standard configuration, I did not see that coming when I bought the boards.
The mini's are such a nice and easy build they just slipped in in the end of my LX521.4 build - which has also been quite a long journey...
Interesting thought to use the 6-24 boards for LX-Mini +2's - or even LX521.4
Any thoughts and updates on that would be highly appreciated
to Noorgard #779
Hello Noorgard,
I think you know that possibilities....😉
ASP LXmini(R)+2 Nelson Pass - LINKWITZ.store
ASP Leiterkarte LX521(R).3 & ORION - LINKWITZ.store
precision ASP LX521(R).4 - LINKWITZ.store
Specially made for use with the LXmini or LX521-speakers.....
Greets
Dirk 😀
Hello Noorgard,
I think you know that possibilities....😉
ASP LXmini(R)+2 Nelson Pass - LINKWITZ.store
ASP Leiterkarte LX521(R).3 & ORION - LINKWITZ.store
precision ASP LX521(R).4 - LINKWITZ.store
Specially made for use with the LXmini or LX521-speakers.....
Greets
Dirk 😀