the pedal steel guitar
… and its many peculiarities – #1.
Mechanical pitch-changing for individual strings and groups of strings, puts varying stress on the pedal steel guitar. Although by appearance and overall design and solutions most PSGs with All-Pull changers are more or less identical, how well the various makes and models hold up for optimal tone, stability and playability, varies greatly.
It is all in the details, and with an instrument that contains so many compromises it is hard to see how any builder can manage to get everything perfectly balanced. After more than 35 years search I have yet to run into the perfect pedal steel guitar, although some definitely are better than others.
I'll leave to others to “rank” makes and models according to individual preferences, while I focus on isolating and dissecting some of the problems players of pedal steel guitars may run into.
hysteresis on the changer
The “slip/hang on the changer” hysteresis phenomenon is caused by too low friction to hold the string steady on the changer during lower, causing it to slip as the tension is lowered and the string contracts, and too high friction to make it slip all the way back again when raised back to neutral. As a result it hangs and pitches too high in neutral after a lower, until it gets kicked/vibrated a little, or gets raised beyond neutral and then released.
It all happens in the area where the string clings to the changer by surface-friction alone - the stretch I have marked in red on the
picture. As lower-action on the changer-top for the forth string is only about 1/20 inch, good luck in seeing a 5-10 cents “slip”
and “hang” with your eyes alone. Easy to hear though…
This is a problem on some but not all PSGs, as it depends on many factors. Length of string from top of changer to hook-up
point, is one factor – the shorter the better.
Length of end-twisting on the string matters too, as the twisting alters the friction between string and changer. One brand of strings may slip while another stay stable, and the string-gauge matters.
What maybe isn't so obvious is that the friction between string and changer decreases when change goes towards lower, and increases when
released back towards neutral. That is why the string may slip at/near fully lowered note, but doesn't overcome the friction to slip back
Raising it beyond neutral after a lower will “over-tension” the string and make it slip back despite increased friction, but that extra raise-action does of course not always fit in with the music played.
In theory one can increase friction over the changer so the string won't slip at all, or reduce friction so it will slip back properly every time after a lower. Neither is practical the way most changers are made today, but it does explain why some changer-constructions show less tendency to slip/hang than others.
Locking the string down about two-tenth of an inch past the top of the changer, so it cannot slip at all, will solve the problem without affecting tone or how far one can lower the string. Not much space for such a locking mechanism on today's changers though.
The “O-ring bumpers” found on some PSGs, will, when set/adjusted right, bump and ease the lower-scissor back to neutral thus cover up and then eliminate the high-pitching effect of the "slip/hang on the changer" hysteresis. I regard it as a stop-gap solution, but it works.
a: Most players who experience hysteresis, seem to focus their attention on the nut-rollers. While hightened friction on badly maintained nut-rollers will tend to cause exactly the same slip/hang effect, regular maintenance will secure freewheeling rollers and eliminate the problem at that end.
b: There is a slight delay in how the strings themselves settle on pitch as they tension and stretch during a raise and contract during a lower. This delayed pitch-stabilisation is measurable on a pedal steel guitar, but any pitch-deviation is too small and righten itself too quickly to be of concern.
The “O-ring bumpers” mentioned earlier will reduce pitch deviation caused by string-settling.
a problem, or not…
Some will recognise the “slip/hang on the changer” hysteresis phenomenon as a genuine problem,
and some will not. To some it is a real dealbreaker, while others won't even notice.
Some who do notice the problem will falsely conclude that it is caused by failures anywhere but at the changer-top, and may end up hunting for it in all the wrong places. One can damage good instruments that way.
There are those who write the phenomenon off as inevitably linked to how pedal steel guitars traditionally have,
and always should, be made. Simply said: fixing such “idiosyncracies” would destroy the instrument's uniqueness.
This is of course total nonsense, but “traditionalists” with such believes do hamper healthy evolution of the instrument.
sheer luck, or…
As my main pedal steel guitars didn't exhibit this particular detuning problem “right out of the box”, it took me a while to recognize it as a problem.
It was only after I modified my “S10 E9” to “Extended E” with extra low-tuned strings (See: E major w/chromatics) that I noticed a slight slip/hang on the lowest string after a five half-note lower. Being an extreme change that I don't use much, I deal with it by varying bar pressure to control pitch until it corrects itself.
As it is as difficult to implement a perfect solution to this hysteresis phenomenon on my main PSGs as on other brands, I have so far not bothered fixing it for the extended low “E” string. If on the other hand they had exhibited the slip/hang problem on the fourth string “E” after lowers, I would have gone for a solution, or shopped for another brand/model that fared better.
While I listen for hysteresis whenever I test-play a pedal steel guitar that is new to me, I recognise that there are so many other inherent peculiarities with this instrument that each individual PSG deserves a “summing up” of all its strengths and weaknesses before concluding.
last rev: 29.apr.2018