One-liners are fun, but not much of a discussion: 😛 When I think about adjusting phase I think about FIR filters, and Dirac Live, etc.
don't think that Papa doesn't know about that stuff; if he didn't cover that in article, it was not his intention within projected scope, which is - as I understood it, to make nice and handy small Swiss Knife, not The Biggest One
go to FW articles and find this fill-in : http://www.firstwatt.com/pdf/art_coherent_xvr.pdf
you can even use it as one of base articles for dedicated thread .... I would follow it for some time, but not for long, as soon presented goes above my head ..... 🙂
go to FW articles and find this fill-in : http://www.firstwatt.com/pdf/art_coherent_xvr.pdf
you can even use it as one of base articles for dedicated thread .... I would follow it for some time, but not for long, as soon presented goes above my head ..... 🙂
If you want an arbitrary phase character independent of frequency response
then you would go with dsp. Otherwise you would adjust the poles of the
analog filters for best fit and be happy.
then you would go with dsp. Otherwise you would adjust the poles of the
analog filters for best fit and be happy.
I guess people will start to replace/bypass the DC blocking capacitors of this nice construction. If one has a highish crossover frequency, the HP output 10uF capacitor could be substituted by e.g. 1uF or even 100nF. Say, the input impedance of the following power amplifier is ~10kOhms this will give 16Hz and 160Hz respectively.
Indeed you can, and SL's earlier crossovers are examples. However I
have found that individually tweaking pole values can do a good job,
as was the case of the Lx-Mini.
I do think I will have to get myself a better A/D converter to explore the
DSP approach further.
Re: substituting 2SK170 for J113
You could end up with lower distortion and noise by replacing the J113 with 2SK170 (at least on the buffer transistors). Leaving the J113 in for the current sources probably makes sense (per Nelson's article), and would leave some more LSK170s in stock for everyone else in the process!
Be advised that the pinout will absolutely require some tweaking, as the J113 and 2SK170/LSK170 definitely do have different pin ordering, and you'll need to replace the biasing resistors when you make the swap.
My plan is to build it with the J113 first, and then experiment with replacing the transistors later.
Similar to you, @soleboy, I have a B4 in play currently with a pair of JBL 4344 - fantastic combo! Looking forward to the added possibilities with another active crossover.
You could end up with lower distortion and noise by replacing the J113 with 2SK170 (at least on the buffer transistors). Leaving the J113 in for the current sources probably makes sense (per Nelson's article), and would leave some more LSK170s in stock for everyone else in the process!
Be advised that the pinout will absolutely require some tweaking, as the J113 and 2SK170/LSK170 definitely do have different pin ordering, and you'll need to replace the biasing resistors when you make the swap.
My plan is to build it with the J113 first, and then experiment with replacing the transistors later.
Similar to you, @soleboy, I have a B4 in play currently with a pair of JBL 4344 - fantastic combo! Looking forward to the added possibilities with another active crossover.
Attachments
...I do think I will have to get myself a better A/D converter to explore the
DSP approach further.
I’ll happily buy that Pass D1 when you’re through with it 😀
Indeed you can, and SL's earlier crossovers are examples. However I
have found that individually tweaking pole values can do a good job,
as was the case of the Lx-Mini.
I do think I will have to get myself a better A/D converter to explore the
DSP approach further.
naah
that's boring
except if you wanna use it as tool, when making your passive and line-level xovers
🙂