Hi all.
I don’t have knowledge to design electrical schemes… I can build very accurately circuits designed by professionals, can change some values which designer suggest to play with.. Probably many DIYers here have same (+/-) skills. In Microcap there is simplified schematics of XO with about 20 passives. Which values should I play with and how? Members like me need simple instruction, something like: increase value of R10 and reduce value of C15 to change high pass, change XX for second pass and so on – just very simple instruction..
I don’t have knowledge to design electrical schemes… I can build very accurately circuits designed by professionals, can change some values which designer suggest to play with.. Probably many DIYers here have same (+/-) skills. In Microcap there is simplified schematics of XO with about 20 passives. Which values should I play with and how? Members like me need simple instruction, something like: increase value of R10 and reduce value of C15 to change high pass, change XX for second pass and so on – just very simple instruction..
Georgeged, my brother...the same boat, the same boat!! Maybe a good soul can help us! I don't need the instructions to be very precise....maybe just point me to where i must start to read about this subject.
Ex:
How do i know where in the frequency range i must cross my full-range speaker? In this case, Markaudio 10.3
If the frequency response curve must be ideally flat, shouldn't i measure the result with a dedicated micro?
Tks
Ex:
How do i know where in the frequency range i must cross my full-range speaker? In this case, Markaudio 10.3
If the frequency response curve must be ideally flat, shouldn't i measure the result with a dedicated micro?
Tks
Georgeged, my brother...the same boat, the same boat!!
yes we are 🙂 we all are diyaudio brothers here ))
I'm googling time after time, reading about active XO's for OB's. if will find something that might help, will share
6L6-
Thanks for guide, and discussion to follow. Cross-overs new subject to learn for me. N78FR, et al much easier!
Thanks for guide, and discussion to follow. Cross-overs new subject to learn for me. N78FR, et al much easier!
Is the minus pole of the barrel, and hence the external power supply, connected to the chassis at the entrance, or is the chassis floating?
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I want to teardown an iPhone for some reason....
2nd order, the LXmini board will do it fine. Adds option for EQ.
You can check out the MicroCap sim if you want to model it.
Thanks Mr Pass
There are plans for a more general crossover.
The LXmini crossover can be stuffed for a variety of loudspeakers.
You have the board and existing schematic, and I have posted a
MicroCap sim file:
www.firstwatt.com/sims/LX_MINI_V1R0.CIR for you to play with.
You can download the Windows demo version of MicroCap from:
Spectrum Software - Micro-Cap 12. Analog simulation, mixed mode simulation, and digital simulation software. SPICE and PSpice(R) compatible circuit simulator.
and alter the values to see the resulting curves.
After installing MicroCap demo, you click on the file and it launches you
into the screen showing the schematic. On the top bar, click on
Analysis, then AC, then Run, and see the result. You can edit the values
right on the screen, and after a little practice you can be doing this on
your own.
Note that the active elements in this sim are VCVS, voltage controlled
voltage sources whose value (gain) is set up as a buffer.
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Dear Mr. Pass, 6L6, ZM, and others
Thank you for offering the LXmini kit to us and the schematic and the SIM software. I already ordered mine it's on the way 🙂
I quickly ran the SIM and it shows that the LXmini Xover circuitry is designed to be at 600 Hz Xover point. I do not see any jumper on the board to switch b/w different Xover frequency.
Please let me know if my assumption is not correct, for a user to select a different Xover frequency i.e 300 hz, or 200 Hz, one has to either play around with the R,C value in the circuit to get to a desired frequency or recalculate the R, and C value and manually solder it onto the Lxmini board ?
In order word, people have to know exactly what specific Xover frequency they want for their stereo system in advance, then play around with the R,C value to get it to that frequency, then finally put together the kit since there's no jumper to switch to different frequencies on the fly as in B4 or B5.
To calculate R,C for Xover LR2 frequency of the Lx-min, do we use formula f-3db = 1/(2pi*RC) ?
Thanks,
Tom

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5 inches by 5 inches.Ready to include this with Whammy as a preamp but can not find dimensions for active x-over board. Anyone?
Answers appreciated. I was planning for two separate power supplies.
However size of board allows for use of 2nd Hammond case to match Whammy. May provide more flexibility and side by side or stacking - may look cool.
However size of board allows for use of 2nd Hammond case to match Whammy. May provide more flexibility and side by side or stacking - may look cool.
Jim, what about the flexibility of changing Xover frequency of the kit as I mentioned earlier. Was my assumption correct?
In terms of You have to change the capacitor and resistor network in order to change the crossover frequency? Yes that is how it works on this board, the easiest thing to do will be get a $100 mini DSP, play with that until you find the crossover points that you like it, and then make the analog crossover at the points you found worked best.
In terms of You have to change the capacitor and resistor network in order to change the crossover frequency? Yes that is how it works on this board, the easiest thing to do will be get a $100 mini DSP, play with that until you find the crossover points that you like it, and then make the analog crossover at the points you found worked best.
Thank you Jim. Appreciate the inputs. I thought so too!
miniDSP in a BOX : miniDSP 2x4
Of course, different units will have more flexibility, but this will get the job done. They also have a mic option for local measurements.
Of course, different units will have more flexibility, but this will get the job done. They also have a mic option for local measurements.
Thanks for the build guide 6L6. My LX-mini ASP kit is on it's way.
Upon reading the documentation I have a question: There is a C29 on the PCB, and referred to in the build guide as a coupling capacitor. But I cannot find this on the circuit diagram. Have I missed something? What does this 10uf capacitor do?
Thanks,
Graham.
Upon reading the documentation I have a question: There is a C29 on the PCB, and referred to in the build guide as a coupling capacitor. But I cannot find this on the circuit diagram. Have I missed something? What does this 10uf capacitor do?
Thanks,
Graham.
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