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Detailed Test Procedures

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About the data collection
To obtain a broad and compelling collection of data and test results we will use:
1 - different test methods
2 - different guitars
3 - various guitarists who do the same tests

Data collection / Methodology
The research methodology will use both 'closed' and 'open questions ' .
In an open question , the respondent is completely free to fill out a response .
In a closed question the respondent can only choose one answer from a pre-given list.
There will also be a mixed format where the respondent must choose from a pre-given list, but also have the ability to add free comments. 
There are advantages and disadvantages to both types of questions:-
Closed questions : can have problems of interpretation , subjectivity , misunderstandings , concepts irrelevant to
respondent , not always reliable , .... However, they have the advantage of fast data processing
Open questions : offer best guarantee of relevance, and describe exactly what the respondent thinks. The disadvantage is that the data are not uniform and more difficult and time consuming to process (also in time). 
In our tests , we will use both closed and open questions.



Preparation guitarist (Test A)
- The guitarist gets in advance a letter with the test procedures.
- He/she is asked if they would like to bring a friend along who has a 'good set of ears' as a good listener!
- The idea is that the friend will also provide his/her judgment on ( nearly all ) the same tests as a listener. 



Communication to the guitarist  (Test A)

Dear,
- We want to run a testing program with 3 guitarists (and listeners) for the Steel-string guitars,
   and a similar number for the classical guitars.

- When publishing the study, test results will not be linked to the name of the guitarist or  listener.
   We will refer only to guitarist Y and X. ... or listener Z ...
- We do plan to mention in the publication and on the site that you cooperated in the assessments (if you agree) as a 
   guitarist or listener.
- In addition to the tests described above , we will during Cordefactum Festival ( www.cordefactum.be )
   
also do a listening test of the guitars for an audience ( 30 to 50 listeners )
 It will be (1) a blind test as the public audience
   will not be able to see the guitarist or the guitar and (2) an non-blind test. Read more about this test in the B section on
   this page. 
   We would appreciate it if you could also take part in this public test as part of the listening audience.
   This would allow you to judge the same guitars from a different angle. We will separately contact you to agree on the
   dates and times of the tests.
   Note: The B/test for steel-string guitar will be on sunday, may 31, 2013 during the cordefactum festival.
   The guitarist will be Jacques Stotzem

Detailed test procedures - Test A
A/Part 1,  PAIR TESTING,  BLIND, assessment of the guitar’s sound (for the guitarist and the listener).
- You will be blindfolded ( welding goggles ). The listener can not see you neither the guitar.. 
- You get to play two guitars in succession (pair) .
- Time Limit: 1 minute effective playing of the pair . ( half a minute per guitar or 
30 seconds)
- You give a rating per pair :  which of the 2 is the best  ? No. 1 or No. 2 ?
   
"No specific preference " is also possible as answer.
- First, the listener gives a written assessment (cross put on 
scorecard) .
- After this you give an oral evaluation to our test administrator who fills the scorecard for you.
- Each guitar is shown and taken away by an administrator.   You should avoid touching the body of the guitar, with the
   exception of the strings/neck as we want you just to play at this stage.

- Test Music: You will prepare your own piece of music for the test of duration ± 1/2 minute.
   You are free to choose anything you like (high to low , solo riffs , chord sequences , loud/quiet.
   Test music can also consist of ' loose' pieces  that are played in succession . Your objective is that your test music will
   allow you to assess as broad a range of sounds as possible within the 30 seconds.
   Keep it simple so you can concentrate on the sound. Test your playing under blind conditions. You should feel
   comfortable with it...

- In total we ask you to assess about 11 to 16 guitar pairs.
- In the pair testing for the steel-string guitars there will be 3 groups of different models. We will inform you each time
   we change the group/model 
( this is only applicable for the steel-string guitar testing. For the testing of the  classical 
   guitars we work with only one model).


- Taking a short break between the pairs is possible. We want the testing to go as smoothly and stress free as possible.

 
Between Part 1 and Part 2 there will be a longer break planned. 

A/Part 2, 
 GROUP TESTING, BLIND, assessment of the guitar’s sound (for the guitarist and the listener). 
Imagine :
- You're in a guitar shop and you want to buy a new guitar and you choose from five guitars.
- You test all five guitars with the same piece of music .
- Then you retake your preferred guitars to narrow down your selection and assessment : You can then rate them as
   follows:
- This guitar I absolutely have to own (very good)
- This is also a possibly buy (good)
- This I am not sure ( average )
- I do not want to own this (poor)
- This, I do not even want to see again (very poor)
  In the first part you will do this test blind and you'll give quotations on the sound.
  In the second part you will do this test NOT blind and you give quotations not only
  on the sound but also on the aesthetics of the guitars ( see procedures below )


2.1 / Blind (for the guitarist and the listener) 
- You will be blindfolded (welding goggles). The listener can not see you or the guitar.
- You get a group of five guitars to play .
- Each guitar is shown and taken away by an employee. You will be asked not to touch them more than is absolutely  
   needed to play them.
- Time limit : half a minute effective playtime per guitar.

After you played the first guitar the listener gives a written assessment (cross put on a scorecard)
   The possible scores are:   1. Very good / 2. Good / 3. Average / 4. Poor / 5. Very Poor /
- When the listener has given his assessment you give your's orally:
   
1. Very good / 2. Good / 3. Average / 4. Poor / 5. Very Poor /
- You both will do the same for the next four guitars.
- You can award different guitars the same rating.
- You should use the same test music for all guitars, as in test 1 but the selected test music may differ from that. 

2.2 / Blind  (only for the guitarist, not for the listener) 
- After having tested the first group of five guitars you replay one or more guitars to refine your opinions. 
- Test Music: You are free to choose the test music, depending on how the instrument inspires you.
- Time Limit: maximum 7 minutes per group of five guitars.
- You now tell the administrator ( verbally ) which guitar(s) you finally found the best, and in your own words you explain
   why. 

- In this way, there are 5 to 6 groups of 5 guitars to assess . ( = 25 to 30 guitars )
- Between the groups you can request to take a short break.

A/Part 3, 
AESTEHICS. Assessment of each guitar’s aesthetics 
3.1 (for the guitarist and the listener) 
- Each guitar is shown and taken away by the administrator. 
- You are now free to touch/feel and see the guitar close up .
Guitarist and friend give their own written assessment (scorecard for each:
   Very Beautiful / Nice / Plain / Not so beautiful 
- Time Limit: maximum 1 minute per guitar for rating aesthetics. 
3.2 (for the guitarist only, not for the listener) 
-explain your preference about the guitar(s) aesthetics in your own words (max 1 min/guitar)

A/Part 4 - PAIR TESTING, NON-BLIND  (same as A/ Part 1, but now NON-blind). (for the guitarist and the listener) 

Pairs of guitars (one T, one L),  are played under non-blind conditions.(30 sec/guitar). Scores are given after each pair. Question: which one sounds the best ? Same pairs as in A/Part 1, but now in a different order. 


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Detailed test procedures  - Test B 
tests for an audience ( blind and not blind )
30 to 50 people will be invited as audience.
Classical guitars and Steel-string guitars are audience-tested one different day's.
This tests will take place during the Cordefactum festival in a small concert hall. 
We will do the 'pair tests' like Part 1 of the A tests. First time the audience is blind, second time the audience can see the guitars and the player and we tell in which woods the guitars are made.

   B/ Part 1
   The guitarist, who is behind a kind of screen, will play (for a very short time) 2 guitars one after the other.
   Each person in the audience gives a written assessment (cross put on a scorecard) after hearing a pair of guitars.
   The question is: which of the 2 guitars sounds for you the best  ? No. 1 or No. 2  "No specific preference " is also possible as
   answer.
   In total we ask to assess about 11 to 16 guitar pairs.
   For the steel-string guitars there will be 3 groups of different models. We will inform the audience each time  we change the
   group/model. For the testing of the classical guitars we work with only one model.
   
Break between part 1 and 2

    B/ Part 2
    Same as Part 1 but now the audience can see the guitarist. 
    Before the guitarist starts playing we will inform the audience in which kind of woods the guitars are made. 
    The pairs will be offered in a different order as in part 1 but the 2 guitars per pair are staying together.



ARE YOU INTERESTED TO PARTICIPATE TO THIS AUDIENCE TEST ? let us know on leonardo.guitar.research@cmbpuurs.be
The B/test for steel-string guitar will be on sunday, may 31, 2013 during the Cordefactum festival. ( time not known yet )
The performing guitarist will be the famous Jacques Stotzem
The B/test for classical guitar... not known yet.


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 C/
physical tests on guitar parts (during construction) and on the stringed guitar

more about this later...




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