I like to listen to music in the dark often, so I cant stand how popular it is these days to add bright blue LEDs to the front of every piece of hifi. My DIY amp simply has a dull red LED at the rear.
How can I electrically modify various hifi components to reduce the brightness of their LEDs?
Thanks
Hugo
How can I electrically modify various hifi components to reduce the brightness of their LEDs?
Thanks
Hugo
Easiest way would be to find the value of the resistor feeding the led and increase it. Try doubling it to halve the current as a starting point, you may need to go more. You might want to only clip the leads off at the body of the resistor initially and solder onto them to avoid too may solder/desolder iterations (which could lift the tracks on the pcb) until you find the value that works.
It it is surface mount that might be tricky.
if the led has flying leads to the pcb then it is easier just cut one of the leads and insert the resistor there.
edit: of course these suggestions would void any warranty! Another option would be to go to jaycar and buy the lowest output colour led of your choice and replace it, however you would need to check the max current which may necessitate replacing the resistor once again...
Tony.
It it is surface mount that might be tricky.
if the led has flying leads to the pcb then it is easier just cut one of the leads and insert the resistor there.
edit: of course these suggestions would void any warranty! Another option would be to go to jaycar and buy the lowest output colour led of your choice and replace it, however you would need to check the max current which may necessitate replacing the resistor once again...
Tony.
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Thanks very much 🙂 I wasn't sure if a series resistor would do it.. Fortunately my main priority is a very nice Chinese preamp with gorgeous point-to-point wiring. Should be easy 🙂
Most leds will happily run off 1 or 2 mA, measuring the voltage source the resistor would connect to and useing Ohms law can then find the resistor.
Lets say its a 24V line, you want say 2V for the LED at 2mA, So that leaves 22V to deal with (burn off in heat). So to get 2mA at 22V (currents in series are always equal), you take 22/.002= 11000ohms. So, if you connect an 11k resistor and LED in series from the 24V point to ground, 22V @ 2mA will flow through the resistor (dissipating 22 x 0.002= 0.044W) and 2V @ 0.002A will flow through the LED. 10 or 11k is thus a good resistor for supplies between say 15 and 24V... you can do calculation based on the voltage you find there. If you want to further improve things, hit an online catalog for low current LEDs.
Lets say its a 24V line, you want say 2V for the LED at 2mA, So that leaves 22V to deal with (burn off in heat). So to get 2mA at 22V (currents in series are always equal), you take 22/.002= 11000ohms. So, if you connect an 11k resistor and LED in series from the 24V point to ground, 22V @ 2mA will flow through the resistor (dissipating 22 x 0.002= 0.044W) and 2V @ 0.002A will flow through the LED. 10 or 11k is thus a good resistor for supplies between say 15 and 24V... you can do calculation based on the voltage you find there. If you want to further improve things, hit an online catalog for low current LEDs.
There definitely is a silly obsession will bright blue led's in any form of product, but especially audio stuff. I hope Temple Audio can hear this....
well its not extra, he just has to find the resistor in series with his led and replace it... I hate bright blue LEDs too.
The best option might be to avoid buying Chinese gear with blue LEDs. I always regard blue LEDs as a warning to keep away, whether on cars or on 'hi-fi'. In either case they suggest that good driving/good sound are not uppermost in the mind.
I agree!
I use an I pod dock- Blue LED in your face! Wire cutters come to mind every time I look at it. LOL. 🙂
I suppose it could be worse- they could flash!
Regards
M. Gregg
I use an I pod dock- Blue LED in your face! Wire cutters come to mind every time I look at it. LOL. 🙂
I suppose it could be worse- they could flash!
Regards
M. Gregg
Actually, there is something worse than a blue LED: using up the remaining supply of NOS magic eyes for 'level indicators' on new gear. Nobody is making them any more, so when they are gone they are gone. Old radio sets and tape recorders which need them will then become unrepairable.
I'd be happy to sell mine, but no-one ever seems interested. So... they're going to be level indicators for my next amp.
Yup over the years I've had so much gear with tape over the LEDs 🙂 Now that my system is almost DONE, I want to have it all done properly
I think that's a tad unfair.. A designer thinking "oh blue would look nice", rather than "oh, red would look nice" isn't a fair way to judge a product!
see: All Pass Labs gear
It suggests fashion-following, which is rarely a good thing. Also, why choose between blue and red when in most cases none is better still? If you need a LED (e.g. to indicate that the thing is powered) then green is most restful to the eyes, and leaves red for warnings which will normally be off.
Well, must I then discard my amplifier with nearly a hundred red LEDs? Green would compromise the performance.
Lamps used to be the indicators, and then came red leds, then green and amber, big time was blue and now hard white.
Prediction....leds that mimic yellow lamp spectrum will become the new 'blue'.
Eric.
Prediction....leds that mimic yellow lamp spectrum will become the new 'blue'.
Eric.
Red for appearance, or forward voltage? Nearly a hundred? I am intrigued.
My amp has three bicolour LEDs, only one of which is visible on the front panel. This shows green for on, and red for bias supply failure. The other two indicate output bias: red means too hot, green means too cold, off means just right.
My FM tuner uses green LEDs to illuminate the signal strength and tuning meters, and to indicate stereo.
I will admit that my CD player has a bright blue LED, which is slightly annoying.
My amp has three bicolour LEDs, only one of which is visible on the front panel. This shows green for on, and red for bias supply failure. The other two indicate output bias: red means too hot, green means too cold, off means just right.
My FM tuner uses green LEDs to illuminate the signal strength and tuning meters, and to indicate stereo.
I will admit that my CD player has a bright blue LED, which is slightly annoying.
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