Tara:
I saw your post on vib vs. rotary and wanted to provide my two cents worth
on the issue.  There are many factors that directly impact the quality of
espresso.  You might consider all of the variables before you prioritize a
single attribute such as pump type.  My primary reason for upgrading from a
Silvia was its relatively unstable brew temperature.  I tried the various
count down and the count up methods and was left dissatisfied with both.
Comments on various threads indicate I'm not alone on this issue.
As such, mastering cooling flushes and countdowns left me more than a little
skeptical.   Having to choose between PID'ing the Silvia and purchasing a
new machine I opted for a new machine, a Brewtus II. Having recently
finished Intelligentsia's one-day barista class I'm able to leverage a
variaty of attrobutes, great beans, a favorite roast and a machine that
complements my reasonable barista skills into a pleasing shot.  I'm not
qualified to debate the merits of one type of pump over the other, but I am
sure that pumps are not the single key attribute to great espresso.
Rob Combs

This is a multi-part message in MIME format.
I chose to upgrade because I could... However, I can tune the pressure
on a rotary far better than I could a vibe pump.
To tune a vibe pump, you have to disassemble the machine and the
pressure valve.
To tune the rotary, you just need access to the pump, and it can be
adjusted in real time.
Do you need a rotary? Nope, but pressure and temperature both contribute
to the qualities of an espresso.
 
For me, I'm pretty convinced that my Giotto has been running both temp
and pressure too high.
Changing to the rotary has given me the motivation to understand the
entire machine and get it dialed in.
 
Oh, if you just want it quieter, I hear that the higher wattage ulka
pump is a bit quieter than the smaller version.
More on my rotary conversion and the results to come.
 
Will
From: homeroast-admin
[mailto:homeroast-admin] On Behalf Of Rob Combs
Sent: Tuesday, August 01, 2006 12:49 PM
To: homeroast
Subject: +Vib vs. rotary
 
Tara:
I saw your post on vib vs. rotary and wanted to provide my two cents
worth on the issue.  There are many factors that directly impact the
quality of espresso.  You might consider all of the variables before you
prioritize a single attribute such as pump type.  My primary reason for
upgrading from a Silvia was its relatively unstable brew temperature.  I
tried the various count down and the count up methods and was left
dissatisfied with both.  Comments on various threads indicate I'm not
alone on this issue. 
As such, mastering cooling flushes and countdowns left me more than a
little skeptical.   Having to choose between PID'ing the Silvia and
purchasing a new machine I opted for a new machine, a Brewtus II. Having
recently finished Intelligentsia's one-day barista class I'm able to
leverage a variaty of attrobutes, great beans, a favorite roast and a
machine that complements my reasonable barista skills into a pleasing
shot.  I'm not qualified to debate the merits of one type of pump over
the other, but I am sure that pumps are not the single key attribute to
great espresso. 
Rob Combs

I don't believe anyone said or implied the pump, whether rotary or vibe, was
"the single key attribute to great espresso". Is there a difference in the
cup between two otherwise identical machines all the rest of the Four Ms
being equal? (Like Andreja versus Vetrano or rotary Bricoletta versus tank
vibe Bricoletta) Some say yes some say no and there seems no real consensus
with blind tasting data to back it up. I've never had an opportunity to do a
blind flight of direct comparison shots from identical machines with the
only difference being the pumps. I do know a rotary Bricoletta is capable of
far better shots than vibe Miss Silvia (with boiler PID). Smoother shots
with more distinct taste characteristics or clariy. But the pump is but one
difference between the machines. Different intra-shot temp profiles, Bric'
more intra-shot temp stable (whether linear intra-shot stability is as
important in the cup as some have proposed is another area of debate and
investigation), Bric' has E61 with pre-infusion etc. 
That said given a choice, I'd never go back to a vibe pump.
Great espresso has many variables beyond a good fresh roasted quality bean
and good quality qrinder and whatever espresso machine with either vibe or
rotary pump or no pump at all(ie manual lever). Loved a recent quote found
on HB that is so true: "In espresso, people tend to focus on tamping,
leveling, and dosing, in descending order of importance. The better focus is
on dosing, leveling, and tamping... in descending order of importance. --
Nick Cho"
Kona Konnaisseur miKe mcKoffee
URL to Rosto mods, FrankenFormer, some recipes etc:http://mdmint.home.comcast.net/coffee/Rosto_mod.htmUltimately the quest for Koffee Nirvana is a solitary path. To know I must
first not know. And in knowing know I know not. Each Personal enlightenment
found exploring the many divergent foot steps of Those who have gone before.
	From: homeroast-admin
[mailto:homeroast-admin] On Behalf Of Rob Combs
	Sent: Tuesday, August 01, 2006 10:49 AM
	
<Snip>
	I saw your post on vib vs. rotary and wanted to provide my two cents
worth on the issue.  There are many factors that directly impact the quality
of espresso.  You might consider all of the variables before you prioritize
a single attribute such as pump type.  My primary reason for upgrading from
a Silvia was its relatively unstable brew temperature.  I tried the various
count down and the count up methods and was left dissatisfied with both.
Comments on various threads indicate I'm not alone on this issue. 
	
	As such, mastering cooling flushes and countdowns left me more than
a little skeptical.   Having to choose between PID'ing the Silvia and
purchasing a new machine I opted for a new machine, a Brewtus II. Having
recently finished Intelligentsia's one-day barista class I'm able to
leverage a variaty of attrobutes, great beans, a favorite roast and a
machine that complements my reasonable barista skills into a pleasing shot.
I'm not qualified to debate the merits of one type of pump over the other,
but I am sure that pumps are not the single key attribute to great espresso.
<Snip>

Thanks for the insights Mike.  I would strongly agree with the last
statement.  Too many people try to cram too much coffee into the PF.
The thinking is "more is better."  Poor Alfred with his single spout
had some of the most unlevel pucks I have ever seen and boy did it
come out in his shots!  Getting him to understand the need for a nice
level basket was a major break through.  An last of all a nice even
tamp!
Les
On 8/1/06, miKe mcKoffee  wrote:
<Snip>