Re: [Harp-L] SPAH Workshop - The Great Comb Debate

[Vern <jevern@xxxxxxx>]

I regret that I will not be able to attend SPAH this year and so will miss your "Great Comb Debate."  I have an intense interest because I claim to have started it about 17 years ago by challenging statements like "wood sounds warm", "metal sounds bright", and "plastic sounds plasticky".  In three public tests, (two at SPAH and one at Buckeye) no expert or ordinary listener or player has yet demonstrated the ability to distinguish one material from another under controlled conditions.  

However, there have been after-the-test complaints about too much noise from the hallway, too much time between plays, too many materials, test harps too leaky, etc. 

 
On Aug 6, 2013, at 9:15 AM, "Tom Halchak" <thalchak@xxxxxxxxxxxxxxx> wrote:
> 
> 
> Each celebrity guest will each demonstrate five identical harmonicas built
> with combs made from different materials.   Four celebrities - five harps
> each - 20 harmonicas in all.  They will offer expert opinions, thoughts and
> comments as they take their turns testing and playing each harp that has
> been specifically prepared for them.

Are we to understand that this will be a preliminary activity to "focus on the intimate relationship between the
> harmonica and the player and between the player and the listener." ?  Sounds like fun and I'm all for it.

>  Afterwards, those in attendance can
> test their listening skills and compete for the coveted Golden Ear Award by
> participating in a random blind test to see if they can correctly identify
> each harp that is being played.

I assume that this part of the program is when listeners can demonstrate their ability to discern comb materials differences.
> 
> No - It's not very scientific.  It is not meant to be a laboratory
> experiment.

Without being extremely "scientific"  or using laboratory equipment, there are some easily-implemented precautions that can be taken to avoid extraneous variables.  I suggest the following:

- Use only one player for this part of the program. Differences between players can mask subtle materials differences.  This will also speed things up.

- Use all 20 harps.  This will prevent the listeners from mistaking differences in tuning and setup for differences in materials.

- Play the harps briefly but a large number of times in random order.   With five materials played once, random guessing can be correct 20% of the time.  The more plays the less chance of an accidental conclusion.  Nothing is as revealing as listeners who hear differences between successive plays of the same material or even the same harp.

- Keep the harps out of the listeners' sight.  They need to recognize sounds, not sights.

- Blindfold the player.  This will prevent knowledge of the material from unconsciously influencing tone.

- Play the harps on a neck rack.  This will prevent variations of cupping from masking the more subtle differences attributable to material differences. 

- Have a person other than the player place and remove the harp in the rack.  This will keep the player from identifying metal combs by their extra weight.

The better you control for extraneous variables, the more reliable your conclusions can be.

You are wise to start the activities at 3:30 pm.  In the past, this type of program has run longer than an hour.  Presumably you can go until your planned program is finished.

Q. What type of harps and what different materials will you use?

Have fun,

Vern