Every musical effect in a piano must originate in the strings. The soundboard, no matter how perfect, can only amplify the sound produced by the strings. Pianos have from 215 to 230 steel strings graduated in length and thickness to produce the 88 notes of a piano's scale design. The shortest string is about 2", the longest string may be 84" or longer.
The bass strings should be pure copper wound, not plated.
 Examine the spacing of the strings in relation to other strings, spaced evenly without touching another string.
 Depressing a key slowly, check damper alignment. At the same time, check as  hammer strikes the strings.
Check to see if hammers strike all of the strings of all notes.
Inspect the strings for even spacing (not touching another string) and proper alignment with the dampers.
Listen to the piano - Is the tonal output powerful enough, at least impressive enough that you should expect from a "classic" piano, but capable, nevertheless, of filling a room no larger than 15 square feet or of a volume not more than say, 2500 cubic feet ?
Is the tonal output reasonably mellow?
 (very bright indicates hardened hammers from age or dry climatic conditions).
Is the tone even and with a fair singing quality ? Is the action satisfactory, that is, does it give a fairly elastic response to your touch ?

The proper weight for key depression is between 2 and three ounces in general. Simply take a scale such as weight watchers, or the postage scale at the post office. Get a few weights (fishing tackle ok) and find a small weight that weighs around 2 1/2 to 3 ounces.. place that weight on any piano keyboard where the fingers play and the key should depress. This is an accurate, but simple way to test for touch, the average touch is around 2 ounces. Get a weight watchers scale and weigh out several coins to make up 2 ounces. Place them where the fingers would be.


Copyright  2011 The "Original Bluebook of Pianos All Rights Reserved