Psyd wrote: If I understand all this correctly:
The GS3 (and others) allows you to open up the valve and allow line pressure in, and at some point engage the pump at high pressure.

From what I've read the GS3 uses a pump assisted pre infusion not line pressure. Below the Speedster price point the only machines offering line pressure P/I are the Vivaldi S1V2 & the Dalla Corte Super Mini.

The GS/3 Paddle uses line pressure for preinfusion: https://www.coffeegeek.com/forums/espre ... nes/426628

So how does that work in pourover mode or is the paddle version strictly a plumb in?

All I can speak to is that the Slayer can set the pre-brew (and post brew trail) pressure anywhere from 0 bars to pump pressure, it is independent of line pressure (Slayer has been run from a sump bucket and performed beautifully). I wish I could offer more info about the other systems, but nobody will let me near their machines for comparison.

Dan

I'm still trying figure why they use a mechanical needle valve for the group instead of a normal 3 way .6mm gicleured down? If the over revved rotary is activated at the first movement of the paddle(stage 1 regulated to say 3 bars), then move a little more and full pressure regulated to say 9 bars starts, seems to me the regulators are switched between with standard 2 way solenoids.
At what point in this pressure curve do you have needle fine adjustment and control?

From what I've seen, it doesn't look that different from a standard Synesso with line pressure(the pre-infuse pressure) regulated. I wonder what they set that one rotary pump pressure at to compensate for three groups going at once, 12 bar, 15bar?

@brokemusician771 - Sounds like you had a great experience. I really need to try a shot from the Slayer.

Thanks. It was a great experience, although I'm looking at my little Gaggia now and.......

Also, I made a mistake in my initial post. It was Jason Prefontaine who I spent time with. I called him Dan.

Not knowing Dan, but after e.mailing and meeting Jason at SCAA, he's a super nice guy. Very passionate about the Slayer, and rightly so.

Great machine, reeks of quality, and produced one of the best shots I've ever had. Twice.

I am trying to figure out why someone is referring to 2-way valves, mechanical needle valves to control the group and over-revved pumps? None of these are features of the slayer machine. Okay, we do use a 2 way valve to fill the steam boiler just like everyone else.

As for pump pressure, multiple group machines have been running on single pumps for decades without "over-revving" or dialing the pressure up to 12-15 bars.


Dan