DIY biamp 6-24 crossover

[Kreisky]

I put this together as part of a revised power supply filter for the diy Sony Vfet and similar amps
to go in the diyAudio store and I have a nice pile of them ready to ship.

This circuit delays power to a relay (or relays in the case of the crossover) which connects the
audio output either to the active circuit (on state) or to ground (off state) by the Q2, R8, C7
portion of the circuit so as to avoid turn-on thump. It also will immediately turn off the output
when the voltage falls below a value set by P1.

P1 is adjusted to where this happens just below the normal operating voltage. The relay(s) have
a flyback diode, and are chosen for the supply voltage. You can parallel or series more than one
relay. The transistors are generic. In this schematic the intended supply 36 volts, but for 24 volts
you would simply reduce R7 to something like 18K.

Works like glue....

The full supply filter board will be posted more generally later.

Hi,

I'm planning to build an LXmini XO with a linear regulated PSU, and I would like to add a soft start to protect the speakers.

This one from NP seems to be perfect for this project, but I have some doubts about the number of filters. A regulated power supply has its own filters, as does the LXmini, if I'm not mistaken.

Could someone with more knowledge tell me if this is a good idea?

Cheers

 

[Kreisky]

Hello,

... Perhaps my question is not clear or it's a dumb question, can I use a linear regulated power supply (sigma 11) + Power supply filter + LXmini crossover?

Sorry for the beginner's question !

 

[R-K Rønningstad]

I am using a linear power supply on one of my 6-24 crossovers. Not problematic at all.
I keep it always on.
And I use the double PI filter with three 1000 uF capacitors and two 10 ohms resistors.
I think the soft start belongs in the power amplifier.
But of course, you could implement a relay and the crossovers output, disconnecting for a few second at power on.

 

[Kreisky]

Hi,

Thanks for the reply! I will keep it simple, I'm looking for 1A linear power supply... If at the end I will need some more filters or relays I will add them. First crossover, slopes and speakers measurement.

Cheers

 

[NewbieAudio]

R-K Ronningstad:
"As long as you keep the coupling capacitors it should be fine"

Thanks for the advice.

Dave

 

[R-K Rønningstad]

if you completely roll your own you could use the B1 Rev 1 topology for the low pass and the B1 Rev 2 topology for the high pass. Use the Toshibas for the Rev 2 and the other JFETs at the bottom end.
The low pass will send the signal through capacitors anyway.
You will ned +/-12 V for the high pass and +24 V for the low pass.
Just an idea that floated in…