Re: measuring output volume from headphones

[Hervé Lissek <herve.lissek@xxxxxxx>]

Dear Stefan,

The major problem doing this is that you don't take account of the charge
impedance of the human ear, which you would directly assess with a coupler
or an artificial ear. 
The method you suggest seems appropriate since you first assess the ear
cavity's charge impedance, but it won't be faster nor much easier than
measuring SPL at the acoustic output of the headphones with appropriate
coupler.

Kind regards,

Hervé

Dr. Hervé Lissek
Laboratoire d'Electromagnétisme et d'Acoustique
Head of the acoustic group
EPFL STI ITOP LEMA
ELB 040 
Station 11
CH-1015 Lausanne
Switzerland
 
Tel: +41 21 693 46 30
Fax: +41 21 693 26 73
herve.lissek@xxxxxxx
-----Original Message-----
From: AUDITORY Research in Auditory Perception
[mailto:AUDITORY@xxxxxxxxxxxxxxx] On Behalf Of Stefan Kerber
Sent: jeudi, 7. septembre 2006 09:53
To: AUDITORY@xxxxxxxxxxxxxxx
Subject: AW: measuring output volume from headphones

A simple way to measure output volume is to measure the voltage at the input
of the headphones (for a defined signal, like a 1kHz sine) and calculate
sound pressure level using the headphones' transfer function. Doing it this
way should also make it easy to change the headphones between different
locations.

Greetings
Stefan

-----Ursprungliche Nachricht-----
Von: AUDITORY Research in Auditory Perception
[mailto:AUDITORY@xxxxxxxxxxxxxxx]Im Auftrag von Robbin Miranda
Gesendet: Mittwoch, 6. September 2006 21:11
An: AUDITORY@xxxxxxxxxxxxxxx
Betreff: measuring output volume from headphones


Hello,
Can any of you recommend a way to measure the output volume/decibel level
from headphones?  We will be testing participants using auditory music and
speech stimuli on two different computers (depending on availability of the
two testing rooms) and would like to make sure that the output volume level
is equivalent at both locations.  We do have a decibel meter (from Radio
Shack), but this doesn't seem feasible to use with headphones.

Thanks,
Robbin

Robbin Miranda
Interdisciplinary Program in Neuroscience
Georgetown University
3900 Reservoir Rd., NW
Washington DC 20007
(202) 687-8449