http://cgi.ebay.co.uk/old-henry-potter-silver-flute-stamped-14-key_W0QQitemZ170039898578QQihZ007QQcategoryZ10183QQrdZ1QQcmdZViewItem chesk this out a simple system flute cylindrical by flute makers guild made for H Potter i have had a shot of one of these before very powerful and play all notes very clear.
David
Simple system flute 
Loren
Yes Loren a simple system flute usually has 6 holes and usually 6 keys sometimes 5 depending whether it has the long f natural. In this case this flute is simple fingering with all covered action each hole covered by a key but the same fingering.
David
Ok, I guess we just learned different definitions for “simple system flute” - that’s the way it goes sometimes with regards to these things.
Loren
“Old System”?
I can buy Brille keys on simple-system, but this is a bit further into the transitional systems, eh?
This was competition for the Bohem flute back in the later 19th century. Everyone wanted to get into the new “Improved” flute market! Kind of like watching this last “Star Wars movie”,I guess we know who one out… 
I’m not that fond of the expression “simple system” (sounds a bit derogatory), but it seems to work and I don’t know a better one. “Old system” might work, but these days people might think that means the Boehm! I get customers referring to their Boehm as the “traditional” or “normal” flute.
“Old system” was an expression used by Rudall & Carte to describe flutes that fingered on the 8-key system, and like the Potter David has pointed us to, that didn’t necessarily mean they looked simple. They worked simple though - although they had lots of keys, these were not interlocked as they are on the Boehm, for increased functionality. This flute gives the idea - normal 8-key in fingering:
(More at http://www.mcgee-flutes.com/BallBeavon.htm )
If anyone know who bought the Potter, I wouldn’t mind a better image of the keywork!
Terry
Ahh, so you’re a Dayton C. Milller Collection definition man then Terry.
I’m with Hammy
"Simple System Flute
1/ The head of the flute has a cylindrical bore, but the body tapers towards the foot.
2/ There are six open finger holes giving diatonic scalse in several keys. Other holes controled by keys give the semitones of these scales. (Although there are keyless flutes as well.( see below))
3/ The flute is always made of wood."
Rick Wilson The 19th century simple system flute, I (too long to repost here)
And more or less of the rest of early music crowd, who seem by and large to feel simple system flutes end somewhere before the point where all the tone holes of the flute are keyed, particularly when the flute is metal as well, and cylindrical as well.
But hey, like much of this stuff, viewpoints and opinions differ. Damn transitional instruments
Loren
So does my M+E polymer count?
Not sure if this is off topic, but i have heard in the dim and distant past, the term ‘Albert System’.
Was this the same as simple system?
I believe when Hammy wrote that, he was referring to historical flutes, of which the M&E is a modern, copy.
Loren
I kind of like it. It makes me want to call the others Rube Goldberg flutes.
I can see it now.
Rube Goldberg flutes are a marvel of modern science.
The parabolic head compresses the sound waves that travel down the
cylinder to a vent of almost equal diameter. A mechanism, manipulated
digitally, is used to open and close these vents changing the length that the
sound wave travels. By changing the velocity of the air stream, the standing
node of these sound waves can be altered in such a way that two or more
notes can be played with the same venting scheme. Indeed, this scientifically
designed mechanism allows the flute to play in all keys in near perfect pitch
in an equal tempered scale.Compare this to the appropriately named simple system flute that uses
holes covered by the fingers of the player to change pitch. This method
of changing the pitch has remained almost completely unchanged since
the times of the > Neanderthal> sounded a note from the hollowed out bones
of his prey. The holes of this simple flute are neither equal in size nor distance
and appear to be random as if a > mollusk > had made the holes resulting in
notes that are not equal in volume and colour. Indeed the key mechanism
is such an integral part of the modern flute, that some > scholars > do
not consider the unkeyed flute a flute at all. The bore of this instrument is equally
random in it’s dimensions.A sub-class of the simple system flute is a higher pitched instrument called a fife,
which many do not even consider a musical instrument.
Not according to that inward looking definition.
BTW, the oldest simple system flutes (as supported by textual and archaelogical evidence) are Chinese dizis , indic bansuris and middle eastern nays. Of these, only the first two are transverse flutes and even these are not covered by that “definition”.
I’m not sure I like Hammy’s definition, and I’m not sure you totally buy it either Loren.
Any Delrin flute, Clinton’s flute for India, and 19th century ebonite flutes (along with Talasiga’s flutes which are made of dried grass) wouldn’t cut it. What was that polymer flute Hammy made…I’m thinking even he would describe it as simple system.
Eric
Yeah… I’d say simple system is just six holes, take 'em off one by one to get diatonic major scale. So that includes irish flutes, that thing up there, tinwhistles, the ones you listed, etc. Maybe with a thumbhole or pinkyhole possible, to include quenas or recorders for instance.
What about the Shakuhachi? It has one less hole.
The thing is (in my uneducated opinion) there is no need to refer to the others as simple system due to the fact that variations of those instruments seem less common than the “concert” flute. Although the others may be under a class of flutes that are referred to as simple system, they are usually referred to with their more precise names (except on Ebay where a whistle will often be called a “Whistle/Flute/Fife”).
Are Baroque flutes concidered simple system?
As a side note, while I was taking lessons from a baroque flute player, he called the “Irish flute” that he had with multiple keys a “modern” flute and only referred to the Boehm flute as a “Boehm flute”. I guess it may depend on the flute clade you belong to.
I’d say yeah, since if you take your whistle and tape off the missing hole it’s the same system (with a fingerhole instead of a thumbhole but still), and there are shakuhachi (what’s the plural? 
) around with the same fingering system as the tinwhistle (my girlfriend’s grandmother has one).
Yeah, I see what you mean. The distinction’s not as important there. But I like categorizing things 
Don’t know much about Baroque flutes. I remember they had some pretty bizarro fingerings 'cause of the tuning system of the times, but they seem simple system to me, maybe with wierd fingerings to temper it. But I don’t know much about 'em.
Oh, that’s interesting! Makes sense too. Cool!
I believe this is incorrect, as “Simple System” was a term coined to refer to flutes with one or more keys, of the type developed (primarily) in Europe between approx 1680 and the time when Boehm come up with his more complicated rig. Debate being whether some of the transitional systems of keying should be classified as “Simple System” or their own system.
So, just because a flute is simple, doesn’t make it a “Simple System” flute. “Simple System” refers primarily to the system of keywork, and secodarily to the other charictaristics common to this type of flute (conical bore, perhaps tuning slide, materials etc.)
So, Dizi, Ney, Shakuhachi, and the older prehistoric flutes, etc. do not qualify as Simple System flutes, they are their own instruments, which fall into a different classification.
With regards to modern “Irish” flutes, let’s remember they are very close copies of historical _keyed_flutes, often absent the keys - which is something that didn’t really exist in a historical context: Who out there has or has seen a Keyless R&R or Pratten’s? We refer to our modern reproductions of these, with or without keys, regardless of the materials, as “Simple System” flutes because that is what they are copied from, even if we choose to leave off the keys, or make them from materials that weren’t available at the time the originals were produced.
Loren
Your first paragraph argument is analogous to an argument that could go something like this (fictional sample):-
The term “car” was first used around the time that crankshafts became redundant. Therefore automobiles prior to that time cannot be called cars.
Noumenon does not precede phenomenon, other than in the gnostic sense.
Chinese dizis, indic bansuris, renaissance flutes, keyless irish flutes (whether conical, PVC, bamboo or wood) all share a common characteristic which overides their many differences. The term “simple-system” flutes categorises them according to this commonality. In the face to face world I have not known any musician or music academic to nit pick this issue.
OMG, I’m agreeing with talasiga.
If it uses 6 sequentially opened holes to produce a major scale, needing keys, half-holing or cross-fingerings to produce other pitches, I call it simple system. Siccama keys are a slight modification. Old Style is a modification. Clinton is a big modification. Skip Healy chromatics are not simple system. Shaks are not simple system. Recorders are not simple system. UP chanters are a cousin to simple system. Thumb holes and D+ holes are moot.
This is 6-hole theory
so simple and perfect
eternal
Dayton C. Miller disagrees, but P.T. Young and I are on the same track.