Your author has several hobbies. Too many in fact. To name a few: video / photographic equipment, cars, gaming, computers and of course hi-fi and listening to music. And well: all hobbies are expensive if you take them seriously. A decent camera lens can cost up to €2000. If you go for a Zeiss cinema lens, you can just add a ‘0’. An Arri model sometimes goes with even an extra ‘0’ behind that. A serious race-sim gaming set-up will also cost 20,000 Euros. Cars and hi-fi we don’t really need to touch, we guess. The sky is the limit. And pc-audio? Well… a decent, linear ATX power supply you can also just smash 5250 Euros on. We take a look at the Jcat Optimo S ATX linear power supply.
Jcat is a Polish manufacturer of ultra-high-end computer audio products. Now opinions differ on the use of a PC for audio applications. And partly we agree with people who don’t like it. After all, a computer is complex, can crash, and has numerous sources of noise and HF-misery.
However, realize that every streamer is basically a computer. And that every streamer runs software that needs to be updated and can therefore fail. Even the high-end models of all well-known brands. We have experienced that a 20,000 euro streamer just breaks, crashes and practically has to be reanimated.
The greatest source of misery in an ordinary PC, however, is not so much the software – even Windows can run and sound great, believe us – but the power supply. A regular ATX power supply works great. But it throws back a gigantic amount of crap onto the mains. We show that in the measurements. That crap goes into your system; know that. Filters help there, of course. But better to address the source. And that’s the goal of the Jcat Optimo S ATX.
More complex than you think
Building an ATX power supply is basically not very difficult. Plenty of brands do it. However, building a completely linear ATX power supply is hard, so Jcat reports . In particular, the power-on speed and sequence of the power supply lines proved very challenging. Especially since this power supply is completely linear.
So what Jcat had to do was make a certain capacity already available, so that the peak can be delivered as soon as the microcontroller indicates that a certain supply line must be opened. We’re talking microseconds here.
Speaking of technology, under the hood are three custom toroidal power supplies. One toroidal transformer is for 12 volts, one is for 5 and 3.3 volts. And the third is for other voltages, think -12 volts and standby. All the power supply lines are insulated. So are the groundings for the power lines. All together, 400 watts is available, which is more than enough for a (very) powerful system.
To keep noise within limits, the tranformers are shielded and there is a large amount of capacitors built in to reduce noise. Both inwards and outwards. We can also see this in the measurements.
(Note: there was a warranty seal on the cap and our unit had to go through to another person, so we decided not to open this unit)
Installing the Jcat Optimo S ATX is not very complex. However, we do see an issue with our PC. We are using a Streacom cabinet for the Alpha Audio PC. It does not have a standard ATX power supply. It has a kind of pico-model, which makes the backplate different. And we can’t (yet) find that in the box. Anyway, we estimate that Jcat will be able to find a way around this.
For normal cabinets neat backplates are available, so all cables can be neatly looped. The cables are nicely sleeved, shielded and fit perfectly. On the back of the Jcat power supply, all outputs are named, so you can see which cable goes where on the motherboard. Just take your time and you will be just fine.
What’s nice is that the Jcat power supply automatically turns on the moment the PC turns on. And it automatically goes into standby the moment the PC turns off. Very nicely done.