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Awesome posts everyone. Especially the ones that were controversial, aggressive, but polite.

***Warning! Long post ahead***

It is interesting how people's experience varies in regards to their feelings of accuracy using the strip. One difficulty of this topic and discussions like it is that each person's idea of what constitutes an accurate tuning varies tremendously.

When Mark C. says he's still not happy with his accuracy in tuning ET, I don't interpret that to mean his tunings aren't accurate by professional standards. I think it reflects Mark's passion about fine tuning - and that he is still pushing himself to the limits of what is perceptible. I also take it for granted that Bill B. is a fine tuner and has also figured out a system that gets him the results he is after in the most efficient and stable way.

One of the most enlightening aspects of being involved in PTG tuning exams is to see the variety of results that working professionals can perform under fairly ideal circumstances. Some come into the exam room very nervous and humble and then nail it. Others come in strutting their stuff and barely make it, or even bomb. My point is, none of us can tell the quality of another's work unless we have the ability to sit down and analyze their work right after it is completed. In general, it is a rare opportunity.

When someone makes a claim that strip muting is faster and accurate, I have to take it with a grain of salt. I'd have to listen to the results myself before passing judgement.

Like Mark C, I used strip mutes for at least 10 years. Some of you might remember why I switched to using single mutes: The first time was because I had accidentally left my strips at a previous appointment! I had to perform a significant pitch raise and tuning with just rubber mutes for the first time, and I really hated it. But some little light went on in my mind. I remembered the words of Jim Coleman from a beginning tuning video where (as he is strip muting the piano) he says "some day you might only tune with a couple of mutes" (or something along those lines).

Looking back, my main frustration with the strips was that I would tune what I thought was an ideal temperament, but when I pulled in the unisons, I was no longer as happy with my beat progressions. Something drifted or changed. I have seen over and over again that two strings together can produce a slightly different pitch result than one string sounding alone. It doesn't matter whether you call it the Weinreich effect, compound harmonic shift, or tuning gremlins. Tuning unisons as you go, eliminates the problem. And tuning notes using two open strings also helps eliminate the problem.

In strip tuning, one string of the unison is the "master" and the other two notes are the slaves. With the open unison technique, two strings of the unison decide where to be "by committee". Once they agree, the third string seems to have negligible effect on what the other two decided.

Tuning unisons as you go forces you to be pickier about your unisons, since you are trying to use them as reference notes. Since I start in the middle and work my way outwards, I'm constantly referring back to the middle, and have the opportunity to catch any unisons that slip.

Tuning with open unisons also trains your ear to cope with more complexity in the sound. I think of it as the ability to "listen through junk". That's one of the reasons I think people have a hard time giving up the strips. The clarity for temperament tuning is very nice. But it is an illusion because once the unisons are brought to bear a certain amount of harmonic shift is unavoidable. You can either deal with it from the get go (no strip method) or later (as the strip is removed).

For pitch raises I regularly use the "pre-tensioning" technique of quickly bringing one string per note up very sharp in the section. Then, as I progress through the tuning I'm bringing two strings up and one string down which often cancels out any drift. I can pre-tension a section in about 30 seconds. There are a few variations of this technique that I use, and I no longer am intimidated about performing a 1/2 step pitch raise with single mutes only.

The claims that strips are faster and more accurate don't hold up to my experience having used both methods. I have a feeling that those who are dedicated to the strip are more tolerant of their ETs actually being mild WTs. For those who obsess with perfecting ET in their everyday work, the open unison approach is indispensable.

Hi Ryan (and All),

It is good to hear many different 'bells'.

Warning! This won't be a long post, as I have to be at work by 7:30am.

I like your incipit, Ryan, when you say "...One difficulty of this topic and discussions like it is that each person's idea of what constitutes an accurate tuning varies tremendously."

In fact, it is not only a question of 'time per se'; as you say, perhaps it should be time-in-accuracy.

In that sense, the whole issue can easly be understood better: let's provide some recordings and demonstrate our points, let's tune 24 notes and unisons, check some intervals and see what we come to, either in a 'given' time or in a 'free' time, along our preferences.

You wrote: ..."The claims that strips are faster and more accurate don't hold up to my experience having used both methods. I have a feeling that those who are dedicated to the strip are more tolerant of their ETs actually being mild WTs. For those who obsess with perfecting ET in their everyday work, the open unison approach is indispensable."

As you say, both "faster" and "more accurate" relate to our idea of what is "accurate"(?); about ETs and 'tolerance', I am not sure...

Where do you get that feeling?

Does your way make you less tolerant of your actual WTs?

No need to say, (edit: if I am given more than 10 minutes) I use a strip and mute from the tenor to the trebles brake. I will post what my experience is, although much of it has already been mentioned by other collegues.

In the mean time, you may try this out: tune three octaves in the mid-range as usual and refine your job (as usual); put the strip down, (edit: check again) and see how happy you are. Please, let me know about your own examination.

Regards, a.c.

This was exactly my experience. I had substantial experience and my capabilities were recognized by others (offered National Technical Services Manager with a major piano manufacturer). But I was never happy with my own tunings. I would tune as carefully as I could, pull the temperament strip and it seemed wobbly to me. So, I figured I just wasn't doing it good enough or I needed another pass or . . .
So, I'd put the strip back in and re-do the tuning -- only to find the same wobbliness upon completion.

Once I started using the method I'd learned from Virgil, my tunings were "locked-in" without that wobbliness.

It made sense to me because I had already been aware of the Scientific American article that dealt with the issue of string coupling. The phenomenon exists -- it's not a matter of opinion or debate. It can be demonstrated and observed easily on any piano 6' or over. This was as practical way to deal with that issue. If you aren't dealing with the string coupling issue, then it's not dealt with and will do whatever it's going to do.

The whole idea of what is an accurate ET and can we get it has also been alluding me. Since I started tuning, I know I've gotten better. I must have, right? Then why do I feel like I am getting worse?

During my research I have been tuning using a beat speed window temperament sequence. If you are happy with the assumptions like G3B3 = F3D4 and F3G#3 = G#3F4 for pure 6:3 temperament octaves A3A4 and F3F4, then my sequence is rock solid. The math is there. There no doubting it. Using this system means your notes will be bang on the first time you set them, provided there is no drift, which is minimized by open unison and double string unison, and provided that your ability to hear small beat speed differences is good, which my research has shown is a piece of cake; everyone who took my test got 3% or better for 5bps.

However, during this research period, I have been recording my sequences at every step of the way. Each step involves setting one interval exactly between two others. Intervals get used multiple times, and each time I have measured them.

The result is that I get a map of each interval's beat speed at different times during the procedure.

The result? I don't want to say, but I will. Some intervals were off the map. Not just dropping, as some would expect, but rising, then falling, then rising again. And yet, most were very steady.

The reasons? I can only postulate:
1) Error in measurements. Frequencies, and hence beat speeds can vary during sustain, so where I measured the waveform could affect the answer. I need to do some calculations to determine the average error possible.

2) After that, I don't know. Slippage? Why up and down, only on some, not others? Board/bridge movement? Again, why the uneven swings.

I have posted the results of my first analysis on the following google docs website. I hope you find it interesting. It also plainly shows my bisecting beat speed window temperament sequence for pure 4:2/6:3 temperament octaves.

Note the following:
Most intervals are fairly constant except C#4F4 and B3D#4, which are completely squirrelly.

Since analyzing my tunings in this way, I am convinced my ability to hear small beat speed differences, and hence my ability to fix some of those errors you see in that temperament, early on, when they are obvious, has improved. I am measuring more recent temperaments now to see if they have improved.

Here's the link:
https://docs.google.com/spreadsheets/d/1AJySQjhpBNDI93robX6m_H1jqOpOOUrG2ss3m8JDK1g/edit?usp=sharing

BTW, there is no way I could tweak the small changes needed to correct these speed ratios without DSU and NSL analysis. As someone said, I would just be wiggling around all over the place.

What were you using to measure the frequencies? Not, I hope, an ETD . . .

The unison is a most important aspect of tuning. I can't understand relegating all of them to a position of almost an afterthought, one last chore to be completed long after the clean breezes of freshness have departed and immediately before leaving the piano.

As a human, I am fallible. I much prefer to have to constantly recheck each and every unison (among other intervals) as I use them as reference notes to tune other notes. I can leave a tuning knowing, not guessing nor assuming that I have done the best I can do in the time given.

I find myself sometimes altering a perfectly still unison when I use it to tune a note a couple of octaves away. Whether there was a miniscule amount of drift or whether I want to change or because I am listening to it differently from the perspective of my ears being focused higher or lower than they were when I originally tuned it is of no consequence, the point is that I spotted a possible improvement among the notes most used. An interval can be given a whole different complexion with an otherwise unnoticeable change made in one of the unisons.

We usually never listen to a unison as closely as when we try to tune another note from it. Certainly not after removing the strip and assuming we infallibly tuned unisons that will stay there.

I am not a control freak but I do like to have as much control over my tunings as possible, even when not much is riding on my skills.

The experienced gained from examination of unisons this closely is cumulative and I find it a lifetimes study in itself. So much depends on good unisons. There is a difference whether a perfectly still unison will start to beat after it has become inaudible and further, whether it would have beat one second or three seconds after it has become inaudible. This kind of attention makes a big difference in sustain and consequently tone colour.

To spot these subtleties would take rechecking the whole tuning in its entirety after a strip has been taken out and making the changes that will certainly become apparent. I have all the time a tuning takes to scrutinise each unison on this way. It takes no longer (unless I make an occasional alteration), since I have to use them anyway in tuning other notes.

In less demanding circumstances, (yes, it could be said I am putting the demands on myself) I have often put in a strip and found the piano to be almost perfectly in tune with the centre strings only and I can refine it and just put in unisons and leave.
I don't do that now because this whole dimension with the unisons remains an open fascination to me and is one of the things that is still keeping me interested and tuning long after my retirement age. Constantly learning and gaining experience.

Putting in the finest of unisons separately is one thing but how do those unisons interact with each other in the finished result? No unison, however beautiful can be heard as a separate entity from the rest of the piano.

Tuning good unisons is the focal point of my work. I tune for the "sweet spot" in the fundamental. I theorized that it has a narrower band of tolerance than the conventional method of listening for the highest possible coinciding partial, because in order for the tambre of the fundamental to change, the complete harmonic progression has to be in alignment. Having been unable to find anything authoritative to back up my theory, I ran it by Randy Potter and Bill Schull. Randy proceeded to diagram how my conclusion was correct; that when the fundamental changes, it is because all of the harmonics are synched, including those we can't hear for whatever reason.

So, I feel that I tune exceptionally clean unisons, and the feedback I get from my customers confirms it.

And I do it with a mute strip.

I don't want to get sucked into this debate on either side. But I just want to say that it is very easy, even for me as an amateur, to observe with TuneLab that I can

1) tune one string spot on
2) then tune the second string to the first as a clean unison
3) mute the first string and measure only the second string with TuneLab and observe that it too is spot on
4) remove the mute and observe that the combination of the two strings is flat according to TuneLab

Weinreich effect or not, it is easy to demonstrate. It doesn't happen always on every pair (or triplet) of strings, and on some pairs it gets more flat than on others. But it is a very real and easily demonstrated effect.

More flat? Not always!

The fact is, confirmed by Weinreich himself, that this phenomenom is not consistent. In some cases the two strings have a higher frequency, in some cases a lower frequency and in some cases they have the same frequency than the one string alone. It can't be predicted. And it can't be quantified. This phenomenom is due to the coupling effect between two strings that when sounded alone vibrate at near but not exactly the same frequency. And when sounded together they couple with each other and vibrate in unison. The frequency of this unison may be higher or lower than the frequency of one string alone depending on the tuning of the second string.

You can read the Weinreich document here:

Gabriel Weinreich: Mistuned Strings

Sorry, I was being inaccurate. I didn't mean to say that coupled strings always go flat. It might as well be sharp. I have mostly observed flatness though. My point was that coupled strings very often does not have the same pitch (on either partial) as either string alone. And that it is easy to demonstrate. Not just esoteric theory.

That being the case, it seems reasonable to tune by the resulting unisons, whether flatter or sharper than the individual strings. Tuning just one string of each not very precisely and then pull in the other strings of the unisons after that will result in pitches not being exactly what you tuned the individual strings to.

As you can read at the end of the Weinreich document, there is a chance that a skilled tuner can reliably control the frequency of the two or three strings unison.

It all depends on our tuning technique and how we tune unisons.

For some of us strip muting works best. The Weinreich effect has also to do with tone and attack/decay times as you can read in other sections of his document.

Which leads us to the quality/color of the unisons.

Weinreich is a very strong reason for me to use DSU, because at the level I am trying to tune ET, the drifting is a problem, especially around octave 6 and 7.

Not sure if you were mentioning Weinreich as a possible reason for the shifting C#4F4 and B3D#4 in my sequence, but it can't be an issue. DSU takes Weinreich out of the equation.


Re:Unisons. After tuning F3A3 < F3D4 < A3C#4, for example, I check A3D4. I try to hear a certain cleaness (and appropriateness, approximately 1bps) of beat. If the unisons are not pure, the cleanliness won't be there. This is another strong reason I use DSU; it forces me to tune more pure beatless unisons. There are SBI available at every step. If you look at the sequence, you'll see.

Unison tuning: strip muting and none.

I may have left the impression that strip mutes are used for the duration. They are not. Only at the outset: Once, to get an overall snapshot, and again or more if a PR/change is called for or if the pitch is all over the place. I then go to wire-handled rubber mutes. Again, for those who learn this method well, it is fast and accurate.

It is not easy for me to condense this info into something that conveys the understandable (my fault not the reader's) but here goes:

I was taught old school with respect to aural tuning. All bi-chords and tri-chords are dressed. One string tuned, then pull mute out and, the other(s) tuned to it respectively. To even tension, each unison is stressed: Hard test blows (fff - it varies) followed by soft tuning key strokes. (Tuning technique is determined by how well or not strings render. Another subject entirely.)

In piano tuning, everything is important especially the unison - the latter if for no other reason than it's the most noticeable and objectionable by pianists when it's out.

If, for example, I spend 2 hours on a tuning (it will vary), around the last 30 minutes of it will be devoted wholly to a final checking of unisons, being certain these are clean, stable and precisely where they need to be pitch-wise as a complete unison. This final step is almost like a tuning unto itself. It's the part I look forward to most - like icing on the cake. At this juncture all strip mutes are gone. The whole instrument is stressed to around fff +/- (it depends). Each unison is given a final check with a single wire-handled rubber mute: string by string, as a whole, and once again in relation to the whole piano.

Such may seem like a tedious, maddening, back-and-forth and even superfluous step in the process, but can make all the difference between a stable tuning and a weak one.

Muteless Tuning?

Who ever heard of such a thing? Maybe some down yonder at the funny farm but certainly not here. Then, many years ago I read an article in the Piano Technicians Journal on tuning a piano without mutes of any kind. I do not recall the author of the piece. I thought the claim was rather exaggerated. Nevertheless, on occasion I would fiddle with the notion somewhere betwixt an octave or interval. Initially, discerning anything in such a cacophonous frenzied state seemed utterly futile. However, miracles still happen and I eventually learned how to focus on the one string out of the other one or two and I gained much respect for the author. (Whoever you are, if you're still amongst the living: Attaboy!)

I supposed that if I'd taken the time to pursue this muteless tuning idea, it might have worked just as well for me. I'll never know. In business it is hard to find time to try every newfangled idea. And when one is completely satisfied with current practice - time tested by respected techs - why bother? If I'd invested the time to test everything proposed in this forum alone, I'd most surely gone broke. Eventually you have to settle on what you know works and go with it.

(Mark, if it were possible, I'd attend your class. Best wishes.)

Working in the homes of private clients presents a situation where obsession can be a problem. You are an invited intruder, but an intruder none-the-less. I've learned to tune as cleanly and accurately as possible, and to do it as quickly as possible. It's a way of respecting the client's time and space.

I use strip muting because I can work faster that way while maintaining awareness of compensations and corrections needed.

The other advantage of using strip mutes is that they can be hung over the edge of the piano to keep interfering cats occupied.

=^.^=

Keep in mind that a tuning meter is not a frequency counter. Ears may be more accurate.

What size of piano are you making this test on? It is more apparent on a 6' plus piano.

You can just check by ear. Tune a perfectly clean octave with the reference note being single string (just to simplify things). Then compare with with the tuned unison muted/unmuted. In over 50% of such tests you will notice a slight miaow that wasn't there before and that disappears with muting. It's there and it's real.

This phenomenon ceases to be noticeable somewhere around a-49 and above

I check my unisons when I'm fininshed; who wouldn't?

But, I can hear a clunker very easily, so it doesn't take me a lot of time discern them. Whenever I hear one, then I get out the wedge and diagnose the problem. For an experienced tuner, unisons should be one of those things we can do in our sleep.

It doesn't take long, and as David says above, I try to respect the customer's time and get in and out as quickly and efficiently as possible, while doing the best job I can do.

I, personally have never found any difference in time taken between the strip method and tuning by completed unisons.

You're right. In trying to be brief I failed to emphasize that strip mute tuning is faster for ME. It's what I learned. I've worked with it enough that it's automatic. I actually tune birdcage pianos and small pianos with two string unisons with unisons-as-I-go. I honestly never saw any advantage in it, so stuck to the strip mute method for other pianos.