Maximise the sound output(dB) of headphones

1
Hi,

I am currently working on a program that outputs white noise using the PsychPortAudio function. The white noise has been created successfully and the output of the white noise is successful as well.

The desired output is to be 99dB. I understand that dB values can be changed via configuration of hardware. I used a headphone as the output source for the white noise. And, a decibel meter app via smartphone was used to measure the decibel value of the headphone upon noise output.
This was done by placing the sound input area of my smartphone(with the decibel meter app running) in between the cupped mufflers of the headphone. It was observed that a maximum of 90dB was achieved. I could not make it any louder. The specifications of the headphone says it is 109dB and the volume of the computer has already been maxed out.

Is there anyway I could increase the decibel value/ volume of the noise being output?

Thanks
Regards
Prasad
2
--- In psychtoolbox@yahoogroups.com, "Diederick C. Niehorster" <dcnieho@...> wrote:
>
> Not being knowledgeble in this area, it still seems like you would need an
> amplifier in between...
> On Wed, Aug 7, 2013 at 6:02 PM, remo3163 <ramhenry@...> wrote:
>
> > Is there anyway I could increase the decibel value/ volume of the noise
> > being output?
> >
>

Hi Diederick,

Sorry for the late one.
I agree, I am currently considering that too as I have a feeling that my hardware's maximum has already been reached and an amplifier is much needed. Thanks.

Regards
Prasad
3
--- In psychtoolbox@yahoogroups.com, Alan Robinson <arcogsci@...> wrote:
>
> 99 db is pretty loud for human ears. Are you sure you need that volume
> level?
>
> I wouldn't trust my smart phone as loudness meter. A low end meter isn't
> that expensive.
> On Aug 7, 2013 3:03 AM, "remo3163" <ramhenry@...> wrote:
>
> > **
> >
> >
> > Hi,
> >
> > I am currently working on a program that outputs white noise using the
> > PsychPortAudio function. The white noise has been created successfully and
> > the output of the white noise is successful as well.
> >
> > The desired output is to be 99dB. I understand that dB values can be
> > changed via configuration of hardware. I used a headphone as the output
> > source for the white noise. And, a decibel meter app via smartphone was
> > used to measure the decibel value of the headphone upon noise output.
> > This was done by placing the sound input area of my smartphone(with the
> > decibel meter app running) in between the cupped mufflers of the headphone.
> > It was observed that a maximum of 90dB was achieved. I could not make it
> > any louder. The specifications of the headphone says it is 109dB and the
> > volume of the computer has already been maxed out.
> >
> > Is there anyway I could increase the decibel value/ volume of the noise
> > being output?
> >
> > Thanks
> > Regards
> > Prasad
> >
> >
> >
>

Hi, sorry for the late one.
Well, we do need it as we would like to create sounds to shock our participants momentarily.
I agree, would you know where to find the cheapest low-end efficient sound meter?

Thanks
Prasad
4
shocking your participants by damaging their hearing isn't a good idea. do you need ethics approval for this study?

it is a very bad idea to have an experiment that uses damaging audio signals, especially using headphones, which pump sound straight into the ear canal. also, since your desired SPL level is already at a dangerous level, any mistakes when running the experiment risk quickly and permanently damaging a participant's hearing.

this is especially worrying since you are an audio novice...


--- In psychtoolbox@yahoogroups.com, "remo3163" <ramhenry@...> wrote:
>
>
>
> --- In psychtoolbox@yahoogroups.com, Alan Robinson <arcogsci@> wrote:
> >
> > 99 db is pretty loud for human ears. Are you sure you need that volume
> > level?
> >
> > I wouldn't trust my smart phone as loudness meter. A low end meter isn't
> > that expensive.
> > On Aug 7, 2013 3:03 AM, "remo3163" <ramhenry@> wrote:
> >
> > > **
> > >
> > >
> > > Hi,
> > >
> > > I am currently working on a program that outputs white noise using the
> > > PsychPortAudio function. The white noise has been created successfully and
> > > the output of the white noise is successful as well.
> > >
> > > The desired output is to be 99dB. I understand that dB values can be
> > > changed via configuration of hardware. I used a headphone as the output
> > > source for the white noise. And, a decibel meter app via smartphone was
> > > used to measure the decibel value of the headphone upon noise output.
> > > This was done by placing the sound input area of my smartphone(with the
> > > decibel meter app running) in between the cupped mufflers of the headphone.
> > > It was observed that a maximum of 90dB was achieved. I could not make it
> > > any louder. The specifications of the headphone says it is 109dB and the
> > > volume of the computer has already been maxed out.
> > >
> > > Is there anyway I could increase the decibel value/ volume of the noise
> > > being output?
> > >
> > > Thanks
> > > Regards
> > > Prasad
> > >
> > >
> > >
> >
>
> Hi, sorry for the late one.
> Well, we do need it as we would like to create sounds to shock our participants momentarily.
> I agree, would you know where to find the cheapest low-end efficient sound meter?
>
> Thanks
> Prasad
>
5
Hi, sorry for the late one,

well, we are performing an experiment which momentarily plays loud sounds at 2 seconds intervals to shock participants.

Well, i used the standardized sound meter app which i think was pre-calibrated. I tried this out with many different sound meter apps and they all gave about the same value which made it seem as if my phone's input threshold was 90dB. Therefore, I guess i may need to get a better sound meter as mentioned???

The sound interface is RealHedTek audio, if thats what you're asking?
Its plugged into the headphone port of the cpu.
I'm not sure of the model, but, Its a phillips headphone with up to 109dB output capacity.

Do you think that the phone is not reliable as its max. input threshold seems to be like 90dB? Is there anyway I could recalibrate this? Or do you think I should just get an amplifier? If so, what type of amplifier am I exactly looking into?

Thanks so much:)
Regards
Prasad

--- In psychtoolbox@yahoogroups.com, "elladawu" <elladawu@...> wrote:
>
>
>
> what headphones are you using? and what audio interface are they plugged in to?
>
> if you are maxed out then you need a headphone amp with higher power output.
>
> and are you talking about dB SPL, or ??? decibels are ratios, they are not units of measurement. did you calibrate your phone's SPL meter?
>
> finally, why do you need a sound that loud, and are you intending to subject human participants to those sounds? noise that loud will damage human ears...
>
>
> --- In psychtoolbox@yahoogroups.com, "remo3163" <ramhenry@> wrote:
> >
> > Hi,
> >
> > I am currently working on a program that outputs white noise using the PsychPortAudio function. The white noise has been created successfully and the output of the white noise is successful as well.
> >
> > The desired output is to be 99dB. I understand that dB values can be changed via configuration of hardware. I used a headphone as the output source for the white noise. And, a decibel meter app via smartphone was used to measure the decibel value of the headphone upon noise output.
> > This was done by placing the sound input area of my smartphone(with the decibel meter app running) in between the cupped mufflers of the headphone. It was observed that a maximum of 90dB was achieved. I could not make it any louder. The specifications of the headphone says it is 109dB and the volume of the computer has already been maxed out.
> >
> > Is there anyway I could increase the decibel value/ volume of the noise being output?
> >
> > Thanks
> > Regards
> > Prasad
> >
>
6
Hi elladawu,

well, yes, we have approval and the participants are notified of the dangers and are told to report to us if they dont feel comfotable at any point of time.
Personally, I have maxed out and tried it on myself and It did'nt affect me, its just like a loud sound for 2 seconds and its gone, but, it truly induces a shock stimuli which is necessary for the experiment.
The participants are well aware of this:).

However, with that being said, since the phone's threshold seems to be of 90dB input, I feel that it is already above 90dB. But, am not sure how much it is.

Thanks Prasad

--- In psychtoolbox@yahoogroups.com, "elladawu" <elladawu@...> wrote:
>
> shocking your participants by damaging their hearing isn't a good idea. do you need ethics approval for this study?
>
> it is a very bad idea to have an experiment that uses damaging audio signals, especially using headphones, which pump sound straight into the ear canal. also, since your desired SPL level is already at a dangerous level, any mistakes when running the experiment risk quickly and permanently damaging a participant's hearing.
>
> this is especially worrying since you are an audio novice...
>
>
> --- In psychtoolbox@yahoogroups.com, "remo3163" <ramhenry@> wrote:
> >
> >
> >
> > --- In psychtoolbox@yahoogroups.com, Alan Robinson <arcogsci@> wrote:
> > >
> > > 99 db is pretty loud for human ears. Are you sure you need that volume
> > > level?
> > >
> > > I wouldn't trust my smart phone as loudness meter. A low end meter isn't
> > > that expensive.
> > > On Aug 7, 2013 3:03 AM, "remo3163" <ramhenry@> wrote:
> > >
> > > > **
> > > >
> > > >
> > > > Hi,
> > > >
> > > > I am currently working on a program that outputs white noise using the
> > > > PsychPortAudio function. The white noise has been created successfully and
> > > > the output of the white noise is successful as well.
> > > >
> > > > The desired output is to be 99dB. I understand that dB values can be
> > > > changed via configuration of hardware. I used a headphone as the output
> > > > source for the white noise. And, a decibel meter app via smartphone was
> > > > used to measure the decibel value of the headphone upon noise output.
> > > > This was done by placing the sound input area of my smartphone(with the
> > > > decibel meter app running) in between the cupped mufflers of the headphone.
> > > > It was observed that a maximum of 90dB was achieved. I could not make it
> > > > any louder. The specifications of the headphone says it is 109dB and the
> > > > volume of the computer has already been maxed out.
> > > >
> > > > Is there anyway I could increase the decibel value/ volume of the noise
> > > > being output?
> > > >
> > > > Thanks
> > > > Regards
> > > > Prasad
> > > >
> > > >
> > > >
> > >
> >
> > Hi, sorry for the late one.
> > Well, we do need it as we would like to create sounds to shock our participants momentarily.
> > I agree, would you know where to find the cheapest low-end efficient sound meter?
> >
> > Thanks
> > Prasad
> >
>
7
"well, yes, we have approval and the participants are notified of the dangers and are told to report to us if they dont feel comfotable at any point of time."

Just because they are notified of the dangers doesn't mean they truly UNDERSTAND the dangers. Plus, there is generally an implicit trust by participants in a lab that it can't be THAT dangerous...

"Personally, I have maxed out and tried it on myself and It did'nt affect me, its just like a loud sound for 2 seconds and its gone, but, it truly induces a shock stimuli which is necessary for the experiment.
The participants are well aware of this:)."

According to the following, a 2 second sound at 96 dB is probably okay, but you need to be EXTREMELY careful that you don't accidentally blast people at something louder than that. Safe exposure times are cut in half for every 3 dB increase:
http://medicine.stonybrookmedicine.edu/surgery/blog/headphones-and-earphones-can-cause-permanent-hearing-loss-what-you-need-to-know

Also, see this: http://www.etymotic.com/pdf/guide_safe_listening_earphones.pdf




On Mon, Aug 12, 2013 at 12:55 AM, remo3163 <ramhenry@...> wrote:

Hi elladawu,

well, yes, we have approval and the participants are notified of the dangers and are told to report to us if they dont feel comfotable at any point of time.
Personally, I have maxed out and tried it on myself and It did'nt affect me, its just like a loud sound for 2 seconds and its gone, but, it truly induces a shock stimuli which is necessary for the experiment.
The participants are well aware of this:).

However, with that being said, since the phone's threshold seems to be of 90dB input, I feel that it is already above 90dB. But, am not sure how much it is.

Thanks Prasad



--- In psychtoolbox@yahoogroups.com, "elladawu" <elladawu@...> wrote:
>
> shocking your participants by damaging their hearing isn't a good idea. do you need ethics approval for this study?
>
> it is a very bad idea to have an experiment that uses damaging audio signals, especially using headphones, which pump sound straight into the ear canal. also, since your desired SPL level is already at a dangerous level, any mistakes when running the experiment risk quickly and permanently damaging a participant's hearing.
>
> this is especially worrying since you are an audio novice...
>
>
> --- In psychtoolbox@yahoogroups.com, "remo3163" <ramhenry@> wrote:
> >
> >
> >
> > --- In psychtoolbox@yahoogroups.com, Alan Robinson <arcogsci@> wrote:
> > >
> > > 99 db is pretty loud for human ears. Are you sure you need that volume
> > > level?
> > >
> > > I wouldn't trust my smart phone as loudness meter. A low end meter isn't
> > > that expensive.
> > > On Aug 7, 2013 3:03 AM, "remo3163" <ramhenry@> wrote:
> > >
> > > > **
> > > >
> > > >
> > > > Hi,
> > > >
> > > > I am currently working on a program that outputs white noise using the
> > > > PsychPortAudio function. The white noise has been created successfully and
> > > > the output of the white noise is successful as well.
> > > >
> > > > The desired output is to be 99dB. I understand that dB values can be
> > > > changed via configuration of hardware. I used a headphone as the output
> > > > source for the white noise. And, a decibel meter app via smartphone was
> > > > used to measure the decibel value of the headphone upon noise output.
> > > > This was done by placing the sound input area of my smartphone(with the
> > > > decibel meter app running) in between the cupped mufflers of the headphone.
> > > > It was observed that a maximum of 90dB was achieved. I could not make it
> > > > any louder. The specifications of the headphone says it is 109dB and the
> > > > volume of the computer has already been maxed out.
> > > >
> > > > Is there anyway I could increase the decibel value/ volume of the noise
> > > > being output?
> > > >
> > > > Thanks
> > > > Regards
> > > > Prasad
> > > >
> > > >
> > > >
> > >
> >
> > Hi, sorry for the late one.
> > Well, we do need it as we would like to create sounds to shock our participants momentarily.
> > I agree, would you know where to find the cheapest low-end efficient sound meter?
> >
> > Thanks
> > Prasad
> >
>