So I've not been super active in the DIY space in a while. But this is what I been up to...
Finally a month or two back got the active XO boards that Murray produced into play. Built as a plankie because they'll not be visible too much. The plan is to eventually stick them inside my SRPP as I have two 9V taps free...reduce number of cables and bits.
Basic setup is source into SRPP (using one of Ian's "small signal controller" R2R selector/volume controls) into the active XO into 4x F5 channels. One on each side goes to woofer, one goes to a traditional passive XO to mid/tweeter in a mostly-finished-but-not-been-worked-on-in-five-years DIT speakers (Scanspeak Revelator/Illuminator)
The idea with the active XO is to be able to drive the woofer directly for more control, as well as easy ability to cross over at the Baffle Step frequency to allow for easy compensation. I was using a little passive component (2 cascaded capacitive filters) board, but it loaded the output of the SRPP a bit (output impedance only 4k or so). Then I put in a MiniDSP 2x4, which worked fine.
The Murray active XO was a LOT better, suddenly made the system come alive.
So I could replace this:
with this:
Yes, those LEDs are a bit bright...
Which lets me do this:
I really need to rebuild those speakers into a better enclosure, they're hacked into an old Klipsch box with a piece of CNCed wood bolted onto the top for the tweeter, filled with stones to make the volume right.
The F5s need to be looked at - rebuilt one with better diode bridge and FETs (the bridge cooked...), have to do the other. And the SRPP does make a fairly substantial, constant volume hiss (shot noise from the valves?).
Finally a month or two back got the active XO boards that Murray produced into play. Built as a plankie because they'll not be visible too much. The plan is to eventually stick them inside my SRPP as I have two 9V taps free...reduce number of cables and bits.
Basic setup is source into SRPP (using one of Ian's "small signal controller" R2R selector/volume controls) into the active XO into 4x F5 channels. One on each side goes to woofer, one goes to a traditional passive XO to mid/tweeter in a mostly-finished-but-not-been-worked-on-in-five-years DIT speakers (Scanspeak Revelator/Illuminator)
The idea with the active XO is to be able to drive the woofer directly for more control, as well as easy ability to cross over at the Baffle Step frequency to allow for easy compensation. I was using a little passive component (2 cascaded capacitive filters) board, but it loaded the output of the SRPP a bit (output impedance only 4k or so). Then I put in a MiniDSP 2x4, which worked fine.
The Murray active XO was a LOT better, suddenly made the system come alive.
So I could replace this:
with this:
Yes, those LEDs are a bit bright...
Which lets me do this:
I really need to rebuild those speakers into a better enclosure, they're hacked into an old Klipsch box with a piece of CNCed wood bolted onto the top for the tweeter, filled with stones to make the volume right.
The F5s need to be looked at - rebuilt one with better diode bridge and FETs (the bridge cooked...), have to do the other. And the SRPP does make a fairly substantial, constant volume hiss (shot noise from the valves?).
