I have Koss DJPro100, 38 ohm, 99dB SPL, and that is the only specs I have.
If I want to build a small amplifier, how do I know what the max AC current is?
If I put 38V on 'em, drawing 1 amp, that would be 38 watts, but I'm pretty sure that would fry 'em.
If I want to build a small amplifier, how do I know what the max AC current is?
If I put 38V on 'em, drawing 1 amp, that would be 38 watts, but I'm pretty sure that would fry 'em.
If they give 99dBSPL at 1VRMS the AC current for that level is 1V/38Ω=0.0263Α or 26.3mA. Power is 1V*26.3mA=26.3mW.
Say you want 117dB SPL peak before breaking something. That's 18dB higher than 99dB. Each voltage doubling is plus 6dB. Thus with 2VRMS they will go 105dB, 4V 111dB, 8V 117dB. Power for 117dB is (8V*8V)/38Ω=1.68W. Current is 1.68W/8V=0.21A or 210mA RMS.
Say you want 117dB SPL peak before breaking something. That's 18dB higher than 99dB. Each voltage doubling is plus 6dB. Thus with 2VRMS they will go 105dB, 4V 111dB, 8V 117dB. Power for 117dB is (8V*8V)/38Ω=1.68W. Current is 1.68W/8V=0.21A or 210mA RMS.
your ear drums will give up much sooner than headphones
besides, headphones can be replaced, but those cillia hair cells do not grow back once damaged
take it easy!
Noise-Induced Hearing Loss (NIHL) | NIDCD
besides, headphones can be replaced, but those cillia hair cells do not grow back once damaged
take it easy!
Noise-Induced Hearing Loss (NIHL) | NIDCD
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True.
Headphones are designed to provide comfortable volume out of cellphones and alike, so 200 to 400mV RMS *tops*
Headphones are designed to provide comfortable volume out of cellphones and alike, so 200 to 400mV RMS *tops*
> 38 ohm, 99dB SPL
The DJPro100 are remarkably under-specced.
In headphones, dBSPL is "normally" re:1mW. Which in 38 Ohms is 0.2V. You should *Never!* need over 120dB SPL. Which is 2.2V rms, 6V peak-peak, or 81mA peak.
Both sections of a '5532, semi-parallel, and a fresh 9V battery, ought to be a heap of drive. (In fact this is kinda what you find in DJ consoles.)
The DJPro100 are remarkably under-specced.
In headphones, dBSPL is "normally" re:1mW. Which in 38 Ohms is 0.2V. You should *Never!* need over 120dB SPL. Which is 2.2V rms, 6V peak-peak, or 81mA peak.
Both sections of a '5532, semi-parallel, and a fresh 9V battery, ought to be a heap of drive. (In fact this is kinda what you find in DJ consoles.)
Not clarified if referenced to 1V or 1mW. If it is 99dBSPL/1mW then for my 117dB example it would take 63mW 1.55V 40.7mA (RMS)
Thanks for the answers
Thank you all for the answers.
I'm not planning on blowing out my eardrums, but when connected to my laptop at 100% volume they are moderate at best.
I'll just build a current monitor circuit and measure what my laptop produces at 100%
Thank you all for the answers.
I'm not planning on blowing out my eardrums, but when connected to my laptop at 100% volume they are moderate at best.
I'll just build a current monitor circuit and measure what my laptop produces at 100%
Is it possible that while you believe you are at 100% output, its just one app, your real level is limited by some other app? I experience that all the time, when watching movie from hard drive, I set to 100% volume, but that is just VLC player, my b&o app which controls total audio is set at 25%.
Any laptop should be able to burn your headphones or ear drums to charcoal. Or you have crappy laptop?
My work dell is painfully loud on skype or zoom if I exceed 20%, on jvc earbuds.
Any laptop should be able to burn your headphones or ear drums to charcoal. Or you have crappy laptop?
My work dell is painfully loud on skype or zoom if I exceed 20%, on jvc earbuds.
You may be correct adason. I tried an online tone generator and the sound was painfully load at 60% volume. That was a single frequency sine wave and not a youtube video. I suspect the videos on you tube and some of my videos that I play with VLC just don't have a high level of volume. Whatever the reason, I would rather set my laptop volume at 50% and adjust an amplifier to the desired listening level.
All of this has nothing to do with my original question though. I was just curious what amount of current would "burn out" the ear pieces in my headphones. The manufacturers don't specify a max watts or current the ear coils can handle.
All of this has nothing to do with my original question though. I was just curious what amount of current would "burn out" the ear pieces in my headphones. The manufacturers don't specify a max watts or current the ear coils can handle.