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Any suggestions for maximizing Tune-Lab's ability to get an accurate stretch. Sometimes it just gives me gibberish and I have to try again and again to get a stretch that makes sense. Also, the bass usually comes out w/not enough stretch. Any suggestions on that?

Use manual settings of the tuning curve.

It's hard to say with the information that you've provided, but assuming that you've taken appropriate samples then try using different octave types in the bass and treble, noting how the tuning curve changes with each different type. For example, 6:3 octaves are the default bass octave type, but using 8:4 or 10:5 will give greater amounts of stretch. If you still feel that it's insufficient then go ahead and use the manual adjustment arrows to add more stretch.

I always take three sample on each "C" and hit the "Save +" each time which then averages all three together to create tuning curve. 6:3 in the bass and either 4:1 or 4:2 in the treble seem to work for most pianos to my ear. You also may want to check the level of your microphone. Sometimes if you play the note too loud, it will peak out and cause distortion.

The fool-proof way to accomplish this is to use your ears with the machine.. (hybrid tuning approach) Works with any ETD that allows for stretch options.

Easy mode: Pre-tune one string of A1, A2 A3 A4 A5 A6

Listen to the octave combinations - if it sounds ok, go ahead and tune the piano.

If you've got some beating in some singles doubles or triples, you've got to move some of the A's. Use the machine as a bookmark - start from the middle and move the offending A's to find a better spot. Then notate where how much sharp or flat the new spot is.. In tunelab you can alter the note and then lock it so it appears red on the graph view. Then use the arrows up and down to get the calculation curve to cross the red locked in notes.

Ron Koval

Thanks for that, Ron. I'll have to try that. One should never fully rely on an ETD - no matter what brand, without confirming by ear. The ETD is just a tool, not a crutch. A crutch results in generic, too perfect, boring tunings. A tool, when properly combined with a good ear, results in the piano coming alive.

Ryan's note about multiple measuring is a good idea, though I don't use the + function... I'll measure, remember the ih constant, toss it, and measure again. I don't want to average in an anomaly! If the two measurements are close, just use the second. If not, go for a third!

With any measuring ETD, take care during the measuring phase to give the machine the most accurate info. With the Verituner, that means taking enough time to let it hear one string first before just banging in the unison.

Ron Koval

I'll go Ron one farther - tune from the break up, then turn off the machine and tune the bass by ear.

I think I'll try lowering the mic volumne. I got a pretty accurate read on a Baldwin D, but couldn't get the program to repeat it. On a Baldwin L (for which I already had a good read on file) the program called for the bass to be made sharp but indicated no stretch in the treble. It's an interesting program and fun to tinker with. The location of the mic also can be important.

I just don't know what I'm doing wrong. I went in early today to tinker w/TuneLab on a Baldwin L. It repeatedly gave me a stretch that was an inverse curve (several cents sharp) in bass and a flat line at 0 for the rest of the piano. Last month on the same piano TuneLab gave me a very nice stretch that was exactly what you'd expect but I can't get it to do that again. Any suggestions? Also, does anyone have a stretch chart for a Baldwin L that they could share? I've settled on a stretch that is +35 for C8 and -13 for A0 but I'm wondering what others have encountered.

I must have 75 different types of pianos saved in Tunelab - maybe even 100. I can always use a saved file I know is good. I can tell if I've got a good measurement on a note. If not, I repeat the same note, or use a neighboring note. Always confirm things by ear for best results with any ETD.

This is what happens when the automatic tuning curve adjustment mode has been inadvertently disabled. You probably switched to manual mode. Switch back to automatic tuning curve adjustment mode and then tap on the tuning curve to trigger a calculated adjustment. Normally this automatic adjustment occurs after every inharmonicity measurement. But since you already did the inharmonicity measurements in this case you can force a recalculation that way.

Thanks Robert,
It took me awhile to figure out that I had to double tap the wrench icon to get to the adjustment modes, but I found it and that did the trick!