CAUT

Expand all | Collapse all

sustain pedal engagement issue

  • 1.  sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-09-2021 08:23

    Greetings Lists,

    A client with hyper-sensitivities is complaining that the sustain pedal on her Boston grand engages and disengages too abruptly. She would prefer that it more gradually transition from off to on, and on to off. If not for her extreme sensitivities, I might alter the efficiency of the damper cut-off by changing the "fore/aft" orientation of the damper heads. But because she so easily becomes preoccupied with extraneous sounds (the present complaint notwithstanding), that would likely be swapping one issue for another.

    Any thoughts about how to thread this needle? Some ideas so far include (as usual, in order from least to most invasive/costly):

    1) altering the angle at which her foot address the pedal (which would be simple, and readily reversible, and in which case the next question would be whether to raise the pedals--and the rest of the piano--relative to her heel, or effectively lower them by raising her heel, which would be my inclination), or;

    2) someone not on these lists suggested shortening the length of the pedal rod, which would increase the amount of lost motion (which would both increase the amount of pedal movement before lifting the under levers, and make it so the foot is closer to horizontal at the moment of engagement), or;

    3) altering the timing of the bass dampers vis a vis the tenor and lower treble dampers (in which case the question would be should the bass dampers lift sooner or later than the rest, and therefore come to rest before or after the rest?), or;

    4) modifying the leverage of the trap work so there is more pedal movement in proportion to damper lift (in which case the questions would be how much and in which direction?) This would be the most invasive of these options, yet still reversible.

    "Scars of experience" responses preferred, but sound speculation also welcome.

    Thanks,

    Alan

    P. S.Please forgive me if this winds up posting twice. My first attempt appeared to be unsuccessful, so I reposted.



    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 2.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-09-2021 10:19
    I would alter the bends at the heads, so that one side (fore or aft) touches down a bit before the other. Which of the two options? Choose by experimentation. A subtle change will create a subtle change. Touchy to make it consistent.

    BTW, the best solution would be a 19th century piano, where the cutoff is less abrupt by design. Different felts, different general design. I was puzzled when I found that Montal (and various famous makers like Blüthner) continued to make over damper uprights into the mid and late 19th century. Designs to shut off very rapidly and completely had been developed since very early on, and Montal proudly exhibited one in the 1840s in which there were dampers fore and aft of the strings. So why did he make the over damper pianino I acquired as late as 1851, and continued to make them beyond? Why did Chickering make an over damper upright around 1859 (see the "Lincoln" piano in the PTGF Museum)?

    The answer lies in the dichotomy between wanting a sharp staccato AND a connectivity, at will. In playing my Montal pianino, once I got it up and working I found that it was much easier to play music of the period (eg Mendelssohn) so it "sounded right." All of those staccato marks for the low bass note, when followed by a leap to a chord, made sense: it didn't sound staccato, it rang. Trying to get a smooth and natural cutoff od sound on a modern piano requires tremendously sensitive pedaling technique, a kind of quiver and bounce to remove a little, then a little more, then shut off. (And then we get into the oink issue as well).

    OTOH, the early German pianos like the Stein, and the early Stodart and Broadwood had very efficient wedge dampers between bichords. Far better for music where articulation and phrasing are prominent. 






  • 3.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-10-2021 09:39
    Hi Fred,

    Apologies for this belated response to your post, which somehow eluded me until now.

    This client has already proved that she can sniff out inefficiencies in damping like an avalanche rescue dog can smell humans through yards of snow. So I am wary of mucking around with the fore/aft regulation of the damper heads in this particular situation (as mentioned in my OP), although it may be just the thing with another client.

    Your point about the relative desirability of efficient damper cut-off is well-taken. Somehow, to me this subject seems like the yang to the ying of the quest for ever louder louds, and increased sustain. But I digress...

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 4.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-10-2021 11:40
    A slight fore aft (or aft fore) progression can be very subtle, and is standard practice for many concert techs. It doesn't need to affect actual damper efficiency in terms of full shut off. It does, however, make the transition less abrupt, and makes "half/quarter/eighth" pedaling easier to do. 

    The main point of what is referred to as half pedaling is to clear a portion of the overall ring while still retaining a portion (as, for example, clearing treble and keeping some bass). If you can just touch down (graze the strings) with one of the two damper pads in a controlled way, this gives additional space between full and partial damping.

    Controlled and subtle are the key words here, and everywhere when it comes to grand damping. Another factor might be just exactly how soft the surfaces of the damper felts are, which can be subltely increased with sandpaper and the like, again making the shut off a wee bit less abrupt.
    Regards,
    Fred Sturm
    "A mind is not a vessel to be filled, but a fire to be kindled." Plutarch













  • 5.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-10-2021 13:45
    Fred,

    Point taken about subtle fore/aft damper head stagger.

    Also appreciate your consideration of the condition of the damper felt, and using sandpaper ("and the like...") to soften. If it comes to removing dampers, I'll definitely give this approach a go.

    Two questions about that:

    1) Would this work on relatively new, clean damper felt?

    2) Please elaborate about what you mean by, "..and the like..."

    Thanks for pursuing this further!

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 6.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-10-2021 17:21
    The question is how hard the existing felt is, and that can be somewhat unpredictable, depending what it was like when new and what the environmental conditions have been. Dampers are something like hammers, in that the actual surface matters a lot to performance. Sometimes they start out fairly hard, sometimes moisture plays a role.

    "The like" can include needling. I like to use thin needles close together, like in the 5 needle tool from Jahn/Pianoforte Supply, for the mono, bi and trichord in the "grooves" (where the strings have compacted), either along with sanding or as a substitute. For flats, it can include peeling - grab a very thin layer, as thin as you can manage to get old of, and pull it off. In the realm of 1 mm. That is for when the surface seems very smooth, like it has been ironed.

    These are things I am more apt to do with older dampers, but there are times when they are appropriate for newer ones.
    Regards,
    Fred Sturm
    University of New Mexico






  • 7.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-10-2021 19:38
    Thanks for sharing your methods, Fred. I got one of those five needle tools from Jurgen a while back, on your recommendation. Great voicing tool. And now this!

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 8.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-09-2021 11:14
    Alan-
    Are the dampers super well timed with the pedal? This sounds counter intuitive, but a pianist with good pedal technique ( which may be part of the issue here...) will be able to half and quarter pedal so much more easily if pedal timing is very good. This can increase some thump on shut off, but makes getting a sheen in between on and off easier to execute. I never underestimate how important it is. If the player uses the pedal like clutching a 56 Dodge, no amount of finesse will work.

    My 0.02

    ------------------------------
    David C. Brown RPT
    Garland TX
    tunermandb88.com
    ------------------------------



  • 9.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-09-2021 13:39
    Hi David,

    The damper timing on this piano is really pretty darn good. You are right that your suggestion does seem counter-intuitive, but I will meditate upon it just the same.

    Thanks,

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 10.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-10-2021 20:27

    Alan,

     

    Well, you could suggest that she do the upgrade path and trade in for a Steinway.  Or better yet, a Shigeru . . .  ��

     

    The unmatched lift rotation of the damper tray vs. the damper levers does 'soften' the lift, making ½ pedaling more sensitive. 

     

    I don't know of any way to convert a standard Kawai / Boston system to the other besides installing a full new damper action.  You could order a Renner action kit and intentionally misalign the pivot points like a Steinway.

     

    Otherwise, the fore-aft tilt is the only real option. For Kawai pianos we make it so there is a very slight lift at the rear (distal end) of the damper head.  But it must be exceptionally small, or you get a high partial leak at shut-off.  If the front lifts first, usually there is a lower frequency leak when the dampers come down which tends to leak longer and be more annoying than the high one at the rear (if any).

     

    Don Mannino

    Sent from Mail for Windows 10

     






  • 11.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-10-2021 21:34
    About executing the aft/fore rise:

    The actual bend is made by placing thumb one end, finger (index or third) on the other, and rotating a wee bit. It's a very subtle bend, and is kind of like back checks in learning to feel when the wire has been flexed just enough to do a permanent bend.

    The other side of the process is focusing on the interface between the pedal and the dampers, honing in on area between the spot where the tray felt begins to compress and the spot where the damper levers begin to move. You want to see a bit of wink of the aft side (toward the bridge) of the damper lifting, slightly before the whole damper head starts to rise. Move the pedal in that tiny range to observe, and see how high the back of each damper rises before the front - comparing each with its neighbors.

    It's touchy stuff, but doable, and with some practice it doesn't take that long. 

    It is conceivable that in some cases the fore side needs to lift first, if the alignment of the damper system (especially the precise spot of the fore edge of the front damper pad and the aft edge of the back damper pad relative to nodes) tells you there is bleed of a particular partial. I've run into the need to make the fore lift slightly ahead of the aft on a few occasions over the years by experimentation, and wasn't attentive enough to remember whether perhaps the damper felts were badly replaced or something along those lines, or perhaps the piano was a fairly small one of low quality and the scaling (position of the dampers relative to the strings) was badly designed. This was more a matter of experimenting to get rid of a noticeable after ring rather than working towards ability to do subtle pedaling. 

    Aft rising first is what I almost always see in well-prepped fine concert instruments. In Steinway it is partly a matter of the design of the tray, but I've seen it in other makes as well. With Steinway, the damper moves along the string very slightly in the fore/aft axis as it rises from and settles on the strings, which probably helps subtle pedaling.

    Regards,
    Fred Sturm
    "I am only interested in music that is better than it can be played." Schnabel






  • 12.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-11-2021 07:31
    Fred,

    Thanks for your elaboration on Don's point (and for confirming that great minds often DO think alike!).

    I will be sure to address whether or not we have the aft end of the dampers starting to rise first on this instrument.

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 13.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-11-2021 07:24
    Hi Don,

    "The unmatched lift rotation of the damper tray vs. the damper levers does 'soften' the lift, making ½ pedaling more sensitive."

    You were the first person, years ago, that I heard make this point. Surprised that Steinway hasn't touted it as a feature. (Makes me wonder if the pedaling advantage was a known, intentional aspect of the Steinway unmatched lift rotation design from the get-go.)

    You can bet that I am going to try everything on my list (starting with understanding the nature of her issue as thoroughly as possible) before proposing the we replace the damper system! Just the same, your point is well taken.

    Thanks also for the insight as to how Kawai regulates for the back of the damper head to lift just before the front, particularly since this piano was built by them.

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 14.  RE: sustain pedal engagement issue

    Member
    Posted 02-11-2021 15:00
    The unmatched lift rotation of the damper tray vs. the damper levers has one draw back or should I say 67 drawbacks. The underlever upstop rail has to be set higher for the tray lift than the key lift. This causes a slight thump on the back of the played key due to the u/l jumping too high.  If you set the upstop for a played key then when the pedal is depressed the u/l's bind.  This is because since the tray pivot is behind the u/l pivot, the tray lifts the u/l pivot higher and binds on the upstop rail. The tray lifts the area at the upstop rail higher than the key lift.

    Be careful when removing a spring from the tray. The strength of the damper assist springs can lift the front of the tray and slightly lift the dampers
    since the top flange is supported by the damper wire.  The spring works both ways.


    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------



  • 15.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-11-2021 16:35
    Jon,

    Thanks for reminding us all that discussion of the pros and cons of matched vs unmatched rotational centers (of the underlevers and the tray) includes trade-offs for the damper unstop rail.

    I'm not clear on your point about the tray spring. How is it that individual underlever assist springs can lift the front of the tray? And does the tray spring counter this?

    Alan

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------



  • 16.  RE: sustain pedal engagement issue

    Registered Piano Technician
    Posted 02-11-2021 18:14

    Jon,

     Yes, we all agree that this is the weak point.  But here is the best solution to minimize the excess upstop space:

    • Regulate the pedal lift so that when the pedal is held down firmly, the black key dampers just dance up a little when played. The white keys should not move the damper heads at all – only the black keys (it's kind of a good test of how even your lift at the key is!)
    • Regulate the upstop rail for about 1mm free motion above the maximum lift of the black keys with the pedal. The white keys will have just a little more motion.  
    • Regulate the sostenuto lift so that it just lifts above the key lift to eliminate the extra motion.  This extra lift with the sostenuto keeps the end of the key stroke from engaging the sostenuto tabs on the sostenuto rail.  If the tabs start being deflected on the sostenuto rail during play this will affect the pianists' ability to make sound.  So it can indirectly affect the tone of the piano.

     

    At least in the Shigeru pianos, this extra space in the upstop is not enough to be felt in the key during normal playing.  I am really bothered by extra damper motion, and I cannot feel it at all when it's set like this.

     

    When Kawai first introduced the Shigeru pianos at NAMM show, I had 2 different pianists comment that "The damper pedal function feels much more controllable than in normal Kawai pianos!"  I didn't think anyone would notice (it is quite subtle), but these unsolicited comments really proved it to me.

     

    Don Mannino



    ------------------------------
    Don Mannino RPT
    Kawai America Corporation
    ------------------------------



  • 17.  RE: sustain pedal engagement issue

    Member
    Posted 02-11-2021 20:01
    Don, thanks for that detail on the upstop rail.

    Alan, The damper assist springs not only help to press the u/l down; they also add lift to the tray. While all the u'l's are suspended by their wires, the springs are still in compression mode and are applying the force to the rail into which they are installed. This force causes the front of the tray to rise. The coil spring counters this but when installing more springs or higher tension, two coil springs are needed; one at the tenor/treble break another at the bass/tenor break. It's better to have the spring closer to the pitman which won't possibly induce a warp from a coil spring being further from the pitman, it doesn't always haooen but I've seen it on a few pianos.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------



  • 18.  RE: sustain pedal engagement issue

    Member
    Posted 02-11-2021 22:35
    This tray lift from the assist springs is stronger on tray/underlever flange rotation that is in-line or matched.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------