malachi wrote:I need another tasting volunteer.

Andy,

Do YOU need any volunteers????

Keith

espressobsessed wrote:Chris, have you messed around with different temps at same extraction ratios?

Yup.
The "temp increment" tests were all using fixed dose, distribution and extraction.

(for mike's benefit) in other words, you grinded differently at each temp to compensate for extraction rates which naturally change at different temps.

Day 11:

So, why is the GS3 worth $4500?

Is it because of the temp stability?
The La Marzocco name?
The cool tricks and tweaks?

Yeah - all of that counts, but fundamentally it is worth $4500 for two reasons.

First - it's built like a tank and it's state of the art and together this means that you could own and use this machine with pleasure and ease for at least 10 years.

Second - it's so damn easy to make great espresso with it.

The latter was made very clear to me today.
I mean, I've noticed already how easy to use it is. And Andy has commented on this to me as well. Greg noticed it as well. But it had not really sunk in until today.

The following are photos of a first-go shot pulled by someone who has pulled less than a half-dozen shots in their life (all on home machines).




A bit tight, a bit slow - the grind needed to be loosened up a tiny amount. But this was a shot that I would have been happy with if served at almost any good coffee bar in the US. First try.
And the second shot... really nearly perfect.

Yeah - so this is someone I've trained in the process of grind/dose/distribute/tamp.
But none the less... the shots were amazing.
Right off the couch - amazing.

And the comment?
"So I don't need to flush or count or anything? This thing is great!"

malachi wrote:Day 11:

So, why is the GS3 worth $4500?

I agree with you whether I get one or not. It has the capacity of any 1 group machine on the market; it is as small as any semi-commercial HX; it is technologically the most, or one of the most advanced machines out there, it's massively well built and drop-dead gorgeous. This is a combination that before this machine came out, I would have regarded as impossible. I'm sure most mavens would have agreed with me. Bill Crossland basically designed something beyond the current envelope of sweet and perfect.

My feeling is that like an original E61 or GS1, buyers of this machine will be able to use it, and if they keep it in good condition, get the price they paid for it any time in the future.

All this remains true whether it improves on the espresso state of the art or not. Given that there are now several manufacturers interested in this goal, an answer to this question will be difficult to give until there's a few years hindsight. Dual boilers have been around since the 80s, PID controls could have been around longer, but were being installed for the last five years. Experience with the combination has made it obvious that the "perfect marriage" of dual boiler design and precise control requires a number of engineering refinements in preheat, head design, water path design, etc. Which machine will end up getting the credit for putting it all together first seems uncertain to me right now. Certainly the GS3 is in the running though.

Abe Carmeli wrote:1) Can you program the preinfusion length, if so, what are the limits? 0.6 secs is very short for preinfusion, as compared to a vibe on most E61 machines doing 4-5 secs.

A clarification.
Total pre-infusion is set, right now, to 3.3 seconds.
0.9 seconds water on; 2.4 seconds water off; then infusion.

espressobsessed wrote:(for mike's benefit) in other words, you grinded differently at each temp to compensate for extraction rates which naturally change at different temps.

Actually... I'm starting to wonder about the idea that there is a direct correlation between brew temp and grind.
I did, of course, have to make many small grind adjustment during the course of each test and each session - but I cannot conclusively say that these were related to changes in brew temp.

It's hard to know for sure because the temp increments were so small - but there were times where I was making micro adjustments to make the grind finer while brew temp was going up and other times where I was going coarser as brew temp increased.

There are just so many variables (grinder heat, environmental factors, burr sharpness) that can go into this... It's hard for me to conclusively say that grind changes in a predictable fashion and brew temp increases (or decreases).

I suppose this is yet another experiment to undertake.

MOSFET wrote:
Andy,

Do YOU need any volunteers????

Keith

Sure.

malachi wrote:Nick nick nick...
Unless someone has done a poor job with their cupping and sourcing, the odds of you having discernable variance in a group of shots of an SO espresso are really low (statistically relevant, yes, but very low).

(emphasis mine)

When you're talking about 2/10ths of a degree Fahrenheit brew water temp change... I dunno... when you're delving into minutiae... can you accuse me of delving into minutiae?

That's where I'm trying to imagine the espresso grounds having a conversation among themselves: "Wow! This water is TEMP STABLE baybee!!! I'm loving this 200.2*F... WAIT... it just changed to 200.4*F!!! EFF THAT!!! Let's give 'em SH*T!!! WHAT KIND OF B.S. IS THIS?!?!"

espressobsessed wrote:Chris, have you messed around with different temps at same extraction ratios?

Hey Schecter!!! Did you see that? He said "extraction ratios!!!"

Nick wrote:That's where I'm trying to imagine the espresso grounds having a conversation among themselves: "Wow! This water is TEMP STABLE baybee!!! I'm loving this 200.2*F... WAIT... it just changed to 200.4*F!!!

I've been thinking the same thing recently, though not with as colorful a metaphor. Specifically in Scace Thermofilter Temperature Device:

HB wrote:

gscace wrote:What about all of those other profiles that you haven't measured? Bury the thermocouple 5mm down inside the cake and you'll get a completely different profile. What is the correct profile there?

To give readers a perspective on just how much placement makes a difference, see the chart below:


Cimbali Junior - puck top and bottom temperatures

That's one thing that really drives me batty about temperature discussions. Someone will say temperature X is THEE correct brew temperature for espresso Y. In reality the coffee is subjected to a wide spectrum of temperatures throughout the extraction.

On one hand, I want to accept what Chris' taste says at face value without the urge to correlate with measurements. On the other hand, I ask myself: This 0.2F degree difference, would it also exist at the mid-point of the puck with such precision, not just the surface? I doubt it; things in nature are rarely so conveniently uniform.