cannonfodder wrote:How do the shots between the speedster and GS3 compare? Is there a noticeable difference in the cup or is the speedsters extra cost simply a matter of art and exclusivity? That is the only box I would trade my A3 in for.

It's been almost three years since I pulled shots on a GS/3. I know there are tasting savants who will give you detailed comparisons between shots they're pulling now and shots they pulled years ago. But as Bob Dylan said, "It ain't me babe."

So, after some weeks with the Speedster, what are your observations and experiences with the beauty? I have talked to another Speedster owner and he is more than pleased, while it is the same league with the GS3, he told me that the output is more gentle, round and smooth.

One practical question: I have setup direct water with an EVERPURE filter and the pressure is at 5 bar, which is quiet high and def. too high for a pre-infusion. Is the pre-infusion pressure identical to the line pressure (just opening the valves without activating the pump)?

Thanks,
- Malte

the_deal_maker wrote:So, after some weeks with the Speedster, what are your observations and experiences with the beauty? I have talked to another Speedster owner and he is more than pleased, while it is the same league with the GS3, he told me that the output is more gentle, round and smooth.

One practical question: I have setup direct water with an EVERPURE filter and the pressure is at 5 bar, which is quiet high and def. too high for a pre-infusion. Is the pre-infusion pressure identical to the line pressure (just opening the valves without activating the pump)?

Without both machines on the counter, I can't compare directly to a GS/3. I can say the Speedster produces beautiful, even extractions and often reveals mid- and bottom-range flavors that my Tricked-out Silvia does not. It sure looks great.

That said, I'm not sure the Speedster is a good machine for people who can taste the effect of 0.1F brew temperature variations -- it won't deliver that kind of performance. But what machine can? The early GS/3 prototype I tested wasn't nearly that accurate -- I don't know about current versions.

The Speedster's pre-infusion pressure is identical to the line pressure, except that with a small gicleur and the preinfusion expansion cylinder, it takes ~7-10 sec to reach line pressure. In your case you might have to install a pressure reducer to bring it down to ~3 bar.

The GS/3 running from its reservoir can do the /pump on/pump off/pump on/ preinfusion that is a cool gimmick but nobody seems to like. If I had a machine that could not be plumbed in, I would probably install a separate pump bypass line with a solenoid valve and pressure relief valve (set to 3 bar) in series. When you were preinfusing, the pump would be on, the solenoid valve would be open, and the bypass would limit pressure at the group to preinfusion level. You'd close the solenoid valve to begin the extraction proper. This sort of mod would be very easy to do but it might add $50 to machine cost, $250-400 to machine retail, and I think the manufacturers are loath to do that.

Hi Andy,

Is there any room in the chasis for insulating the steam boiler? If so, what thickness do you think? Hard to see from photos...

With the exposed group to radiate some heat, do you think that insulating the brew boiler also would still allow the PID enough room to move?

It gets to 33C here in summer (pretty much all day AND night) and I pump a huge amount of power into the aircon, if I can do anything to reduce the heat coming from the machine that would be a bonus.

Cheers, Chris

AndyS wrote:The Speedster's pre-infusion pressure is identical to the line pressure, except that with a small gicleur and the preinfusion expansion cylinder, it takes ~7-10 sec to reach line pressure. In your case you might have to install a pressure reducer to bring it down to ~3 bar.

The GS/3 running from its reservoir can do the /pump on/pump off/pump on/ preinfusion that is a cool gimmick but nobody seems to like. If I had a machine that could not be plumbed in, I would probably install a separate pump bypass line with a solenoid valve and pressure relief valve (set to 3 bar) in series. When you were preinfusing, the pump would be on, the solenoid valve would be open, and the bypass would limit pressure at the group to preinfusion level. You'd close the solenoid valve to begin the extraction proper. This sort of mod would be very easy to do but it might add $50 to machine cost, $250-400 to machine retail, and I think the manufacturers are loath to do that.

Hi Andy, love the new machine. I had a little look at Kees' stand in Copenhagen and it was a very well made machine. Good on him for producing his own group and boilers. The pre-infusion options he has provided make a lot of sense, I tend to lean towards a built-in consistent preinfusion rather than a manual one to keep things simple. For a single user sure a manual one would be fun but for retail operations a chamber or cylinder would be necessary for consistency. On the really manual machines I have I tend to PI by counting seconds rather than doing it on the fly.

I agree the electronic pump pause is not that useful, but your point about some sort of bypass system is in the works. I won't hijack this thread now but maybe leave it for another time, but this system you describe is exactly what the new LM paddle does, but the bypass is at the group head. I've been playing on the new paddle I have and you can control the pressure manually from line to 9.

gyro wrote:Is there any room in the chasis for insulating the steam boiler? If so, what thickness do you think? Hard to see from photos...

With the exposed group to radiate some heat, do you think that insulating the brew boiler also would still allow the PID enough room to move?

It gets to 33C here in summer (pretty much all day AND night) and I pump a huge amount of power into the aircon, if I can do anything to reduce the heat coming from the machine that would be a bonus.

Cheers, Chris

Any news on the arrival yet Chris? I bought some thermal insulation wool in HK before, it was around 8mm thick.

Paul

Paul_Pratt wrote:I've been playing on the new paddle I have and you can control the pressure manually from line to 9.

Hey Paul,

does it mean that you are able to "step-less" increase the pressure from line pressure (3 bar) to brew pressure (9.x bar). In other words manual pressure profiling is possible? I wasn't aware of that, thought the paddle version can be operated in three modes: off/infuse/brew.

Thanks,
-Malte

Hi Paul, hopefully arriving before the end of the month. Thanks for those bits and pieces for the Elektra MCaL, they worked a treat... I might have to ring you sometime to see where you got the thermal insulation wool from!

Cheers, Chris

Hi Malte,

I didn't mean to get your hopes up because it really is off/infuse/brew in the 1 group config. But today I was playing and was able to get it so I can increase brew pressure as I slide the paddle. If I have time tomorrow I shall take some pics and maybe start a new thread.

Paul

Now we are talking

Maybe this thread would be better? Preinfusion on the La Marzocco GS3

Paul_Pratt wrote:I had a little look at Kees' stand in Copenhagen and it was a very well made machine.

I agree. It obviously is a striking design, but it is really beautifully made, too.

Paul_Pratt wrote:Good on him for producing his own group and boilers. The pre-infusion options he has provided make a lot of sense, I tend to lean towards a built-in consistent preinfusion rather than a manual one to keep things simple. For a single user sure a manual one would be fun but for retail operations a chamber or cylinder would be necessary for consistency. On the really manual machines I have I tend to PI by counting seconds rather than doing it on the fly.

I think you're right. People seem to get excited about manually controlling brew pressure, but to me that's a PITA. I'd much rather program a profiling pump and let the electronics repeat the profile without my input. Or just go with a decent preinfusion setup and a standard pump.

Paul_Pratt wrote:I agree the electronic pump pause is not that useful, but your point about some sort of bypass system is in the works. I won't hijack this thread now but maybe leave it for another time, but this system you describe is exactly what the new LM paddle does, but the bypass is at the group head.

So it bypasses HOT water? Back to where? The drain?

gyro wrote:Is there any room in the chasis for insulating the steam boiler? If so, what thickness do you think? Hard to see from photos...

With the exposed group to radiate some heat, do you think that insulating the brew boiler also would still allow the PID enough room to move?

Hi Chris:

I think there's some room, not a lot. Actually I believe Kees is experimenting with boiler insulation for the Speedster, but as you can see from the pictures, mine isn't insulated.

I don't know how insulating the brew boiler would affect thermal accuracy, but it would be simple enough to test.

AndyS wrote:I think you're right. People seem to get excited about manually controlling brew pressure, but to me that's a PITA. I'd much rather program a profiling pump and let the electronics repeat the profile without my input. Or just go with a decent preinfusion setup and a standard pump.

It's amazing how much trouble people will go to . . . . . to try to get a rotary pump to mimic a $30 vibe pump.

ken

AndyS wrote:So it bypasses HOT water? Back to where? The drain?

Down the drain. It will divert pump pressurized water away from the coffee down the 3 way, the more you move the paddle to brew the less down the 3 way and more onto the coffee.

Ken Fox wrote:It's amazing how much trouble people will go to . . . . . to try to get a rotary pump to mimic a $30 vibe pump.

Now now Ken

Ken Fox wrote:It's amazing how much trouble people will go to . . . . . to try to get a rotary pump to mimic a $30 vibe pump.

Although vibe pump do come up to pressure more slowly than rotaries, many people (even Ken Fox, IIRC), report that some sort of pump-delay preinfusion is still necessary for best results.

Once you start modifying your machine with aftermarket pump delay relays, you no longer are dealing with a "$30 vibe pump." Profiling pumps can do what your delay relay does and more.

Not to mention the fact that if I had to listen to a stupid vibe pump rattling the glasses in my kitchen cabinets every morning, I'd probably give up espresso and stick with drip.

Paul_Pratt wrote:Down the drain. It will divert pump pressurized water away from the coffee down the 3 way, the more you move the paddle to brew the less down the 3 way and more onto the coffee.

Makes sense, although obviously it wastes hot water (not a "green" machine).

AndyS wrote:Although vibe pump do come up to pressure more slowly than rotaries, many people (even Ken Fox, IIRC), report that some sort of pump-delay preinfusion is still necessary for best results.

Where did I say that? I do believe that pump-delay preinfusion is helpful in rotary machines that would otherwise go directly to 9 bar without any sort of pressure ramp up, especially if one updoses. I never advocated any sort of pump delay on vibe machines. It was when I bought a new rotary machine that I noticed that it was not forgiving of updosed baskets (I had been updosing for years without even realizing it) whereas the vibe pump machine never gave me any problems with that, presumably due to its "built in preinfusion."

AndyS wrote: Once you start modifying your machine with aftermarket pump delay relays, you no longer are dealing with a "$30 vibe pump."

why would anyone do THAT?

AndyS wrote:Profiling pumps can do what your delay relay does and more.

the only thing missing is any sort of proof that this sort of modification produces "better" shots than does an unmodified vibe pump.

AndyS wrote:Not to mention the fact that if I had to listen to a stupid vibe pump rattling the glasses in my kitchen cabinets every morning, I'd probably give up espresso and stick with drip.

If I am not incorrect, the rotary pump in the Speedster is "outboarded." Dan has previously illustrated, in another thread, that "outboarding" a vibe pump eliminates most or all of the noise that comes from this sort of pump.

ken

Ken Fox wrote:I never advocated any sort of pump delay on vibe machines.

Oops, I could have sworn I read that in a recent thread.

Ken Fox wrote:the only thing missing is any sort of proof that this sort of modification produces "better" shots than does an unmodified vibe pump.

True, but espresso is an aesthetic experience, and the vibe pump ruins my mood.

Ken Fox wrote: Dan has previously illustrated, in another thread, that "outboarding" a vibe pump eliminates most or all of the noise that comes from this sort of pump.

Hey Dan, you still using that outboard motor?

Ken Fox wrote:It's amazing how much trouble people will go to . . . . . to try to get a rotary pump to mimic a $30 vibe pump.

ken

Maybe it would be more accurate to say it is amazing how much trouble people will go through to try to get a rotary pump to mimic your arm and a lever. Might be why I just can't cut the cord on having a manual lever machine around for occasional use.

cannonfodder wrote:Maybe it would be more accurate to say it is amazing how much trouble people will go through to try to get a rotary pump to mimic your arm and a lever. Might be why I just can't cut the cord on having a manual lever machine around for occasional use.

Lever machines don't get anywhere close to 9 bars of extraction pressure . . . .vibe pumps came after levers, but they preceded the widespread use of rotary pumps by decades. Vibe pumps by design have a slow pressure ramp up, and when unregulated can go up considerably above 9 bar (which we address with OPVs).

So, I think actually that my statement was more reflective of what has been attempted with rotary pumps, in order to get "preinfusion," otherwise known as a slow pressure ramp up at the first part of the extraction. The thought could perhaps be clarified by changing it to reflect the pressure curve of a vibe pump operating with an adjusted OPV.

ken