So I'm interested in building HiFiSonix's KX design, but I want to do something a little different and I'm hoping to get a little guidance on my options.
I want to turn them into monoblocks that I locate near the speakers that they are powering. I also want to run the power supplies in separate chassis.
the whole idea stemmed from my desire to build the base schematic, then make an additional mono one for a sub, but then I got to thinking why not make them all monoblocks, further signal separation should be somewhat beneficial or at the least not harmful.
The part I'm going to need a little help with is the power supplies. I'm sure I can just go with some off the shelf ones if I want, but I'm not sure what specs I need for them. I see that it's 26-28VDC or 35VDC in AAB mode, but at how many amps? I would like to build my own PSUs eventually but for now I want to get the amps built and working quickly and somewhat cheaply. Any advice?
I want to turn them into monoblocks that I locate near the speakers that they are powering. I also want to run the power supplies in separate chassis.
the whole idea stemmed from my desire to build the base schematic, then make an additional mono one for a sub, but then I got to thinking why not make them all monoblocks, further signal separation should be somewhat beneficial or at the least not harmful.
The part I'm going to need a little help with is the power supplies. I'm sure I can just go with some off the shelf ones if I want, but I'm not sure what specs I need for them. I see that it's 26-28VDC or 35VDC in AAB mode, but at how many amps? I would like to build my own PSUs eventually but for now I want to get the amps built and working quickly and somewhat cheaply. Any advice?
I hope Andrew will answer to give you the details. But I can say that it depends on the idle current. I would assume you are not going to run the sub amp in high bias mode? In that case you could run the higher voltage and get some more power to your sub. I think if you go 200VA per amp you're ok. I built a dual mono and got 250VA 22V (a bit high voltage for high bias) toroids from Toroidy, since the price difference was very small from 200VA.
However, I think it might be wiser to get another amp for your sub, a good class D maybe? LF needs a lot of power compared to higher frequencies.
However, I think it might be wiser to get another amp for your sub, a good class D maybe? LF needs a lot of power compared to higher frequencies.
For full class A mode on +-28-29 VDC supply rails you will need 1.2 Amps per channel so 75W constant draw. For class A the general guidance if you are using a standard linear PSU (transformer, rectifier and smoothing caps) is to go for 3x the constant power draw so a 200 VA transformer minimum in a single channel monobloc as Sam says. I strongly recommend if you are getting them custom made you get an interwinding screen and a GOSS band, even if you keep the PSU separate.
I heard Torroidy transformers from Poland make very good audio grade transformers.
I don’t recommend class A for sub duty. A good option here are hypex class D modules.
I heard Torroidy transformers from Poland make very good audio grade transformers.
I don’t recommend class A for sub duty. A good option here are hypex class D modules.