Subject: Re: measuring output volume from headphones From: =?iso-8859-1?Q?Herv=E9_Lissek?= <herve.lissek@xxxxxxxx> Date: Thu, 7 Sep 2006 10:39:14 +0200Dear 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@xxxxxxxx -----Original Message----- From: AUDITORY Research in Auditory Perception [mailto:AUDITORY@xxxxxxxx On Behalf Of Stefan Kerber Sent: jeudi, 7. septembre 2006 09:53 To: AUDITORY@xxxxxxxx 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@xxxxxxxx Auftrag von Robbin Miranda Gesendet: Mittwoch, 6. September 2006 21:11 An: AUDITORY@xxxxxxxx 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