LX-mini Crossover Article

[Nelson Pass]

I think what you will like about this one is the +/- 1 octave adjustment range
of each of the 1 - 4 poles per filter. Gives some adjustment wiggle room you don't
normally get.

 

[JuleZ3C]

Yeaaahhh, bring it on baby! hmm Sir!


Getting tired of my low humming, 'did-it-myself' POS proto board(s)



Adjustment range sounds very cool indeed!

 

[Nelson Pass]

BTW, I am bringing a few LXmini crossover kits - board, semis, resistors, caps
to distribute at BAf tomorrow.

 

[cubicincher]

to Nelson Pass #621

Hello Mr. Pass,


this will become a very nice active crossover!


One octave adjustment per pole sounds very good.



Thanks for your efforts on this project. I think you are extremely busy before BAF....


Greets
Dirk

 

[signalbeach]

I think what you will like about this one is the +/- 1 octave adjustment range
of each of the 1 - 4 poles per filter. Gives some adjustment wiggle room you don't
normally get.

Hi Nelson,
Will it be possible to use the new crossover in a balanced configuration with 2 poles per filter ? If so, do you recommend any component matching between the + and - phases if operating balanced ?

BTW, I'm using a Pass Int 250 integrated amplifier. Is there any easy way to bypass the preamp section of my Int 250 ? I probably need to implement a master volume control and input switching separately.

I'm excited to see the crossover. Thanks for all your efforts for the DIY community !

 

[chromenuts]

Ignore me...did some back reading. Thanks for this Pa.

 

[Nelson Pass]

Hi Nelson,
Will it be possible to use the new crossover in a balanced configuration with 2 poles per filter ? If so, do you recommend any component matching between the + and - phases if operating balanced ?

BTW, I'm using a Pass Int 250 integrated amplifier. Is there any easy way to bypass the preamp section of my Int 250 ? I probably need to implement a master volume control and input switching separately.

You can tap into the points on the existing board, and may have to cut
some traces, but it can be done. Easier just to get two of them and use
one board for each balanced channel.

I don't know about the bypass of the INT250 preamp. We will have to
ask Wayne.

 

[DUC985]

Can somebody enlighten me how the EQ works and how to calculate the values. I did try to modify the values to reflects a 250Hz Crossover with a 40HZ bump for an open baffle.
My initial thoughts are to leave the EQ out ...

 

[Nelson Pass]

It's not a "standard" circuit, but is easily simulated. The schematic you see can
be entered into MicroCap (free from spectrum software) and you can play with it
until the cows come home....

 

[DUC985]

thx Nelsom, i understand what it does, sounds like a specific requirement for the LXMini so speaker specific ..

 

[tamra]

Hello.
I have started diyaudio few years ago so
I apologize for my noob questions.
I have ordered 2 basic pcb for analog
crossover.
I am planning to cross over sb acoustics satori 2 way.
Now I have a hypex ucd180 amp and
300B tube amp.
I also interested in building firstwatt amp.
My DAC is topping D70.
This DAC have xlr and rca output together same time.
So my question is if I can biamp xlr and rca amp together.
Or I should make another hypex amp then biamp same
amp.
I also interested in building firstwatt amp.
I have bought 3 pairs of 2sj74bl/2sk170bl because sounds like running out...
But my plan takes few years though.
So many things to learn.

 

[Nelson Pass]

Of course you can bi-amp with xlr and rca together.

 

[tamra]

Thank you.
I am looking forward to receive
cross over kit ��

 

[comickitkit]

Lxmini with Subwoofer

is it tailor-made for LXmini? Or it can change some parts value to be used in Lxmini with Subwoofer?
Thanks

and the first version of the board

 

[Nelson Pass]

It can be adjusted for the Lxmini with subs, and you have to add an external
low pass filter for the subs. Probably worth a small article.

 

[Variac]

This might be a logical way to go. Giving LXmini 2way crossover owners a way to upgrade to the subs in the future. If designed with the correct size and shape, an add-on low pass filter board would probably fit into the existing chassis, which already has connectors for the 3-way crossover

 

[Zen Mod]

Yo, Iguana Mate

where is Da Porn of bribe , you got to move Mighty ZM , before full occupation of SR Workshop ?

 

[Variac]

You mean the incredibly cool gift Papa gave me as a bribe to take you away from his house and make sure you were gone on the plane? (for everyone else: it was a B1 buffer with the addition of some “iron supplements” (transformers) to give it a touch of gain!. Still, it won’t drive an F4 loud!) Actually I volunteered to take ZM to the airport and no bribe was necesssary but Papa is crazy generous....

The sad truth is I had so much loot to take to Costa Rica, speaker parts and bicycle parts, and an oscilloscope ..that I had to leave it for Dana in Santa Rosa to play with. I made sure he knew he has to give it back! He was curious how his F5’s would sound with a little more “push” I should make him take a photo.

Thanks Nelson!

 

[Zen Mod]

B1T , as far as I remember it's called
blatant, and Poor Man's iteration of Iron Pre ........

Funny Pa!

 

[comickitkit]

Thanks so much, Nelson Pass.
If possible, I would like to work on 2 of your crossover boards and only 3 channels are used for one side of lxmini. If you can kindly furnish which components have to be change on its value for using on the subwoofer, it will be very helpful for me to complete my little project

It can be adjusted for the Lxmini with subs, and you have to add an external
low pass filter for the subs. Probably worth a small article.