Low Current LEDs (and power saving)

[rullywowr]

Just curious if any of you use/used to use/swear by/dislike "Low Current LEDs?"  Mostly for LED indicators in pedals.  Also wondering if they may "sound" different to your ears when used in a clipping circuit?  The ones I came across here have a fV of about 1.9v.

These are about 0.20c a pop at Mouser and draw 2mA.  2mcd brightness (typ).
http://www.mouser.com/ProductDetail/Vishay/TLLR4401/?qs=%2fha2pyFaduhWRCNY2UVIVjQcNqusW51tP1yt1W7WiKc%3d

The bulk of vanilla LEDs I have come across in the past consume somewhere around 20mA.  My focus of the week is reducing power consumption with various methods and just stumbled across these.  It's not a huge deal when running off an adapter but I have been working on reducing power usage for battery powered circuits.  These may have their place...

[midwayfair]

That's neat. How do they compare in brightness? In the real world, not on a datasheet.

[davent]

I just use regular high brightness LED's, dare i say Tayda's, and they usually only require much less then 1ma to be bright enough for me, so 10k-18k for a current limiting resistor...  have some greens that were fine with ~50k. I only use led's for visual reference. I visually test each led for it's needed CLR.

dave

[rullywowr]

That's neat. How do they compare in brightness? In the real world, not on a datasheet.

That's what I was wondering!   

I just use regular high brightness LED's, dare i say Tayda's, and they usually only require much less then 1ma to be bright enough for me, so 10k-18k for a current limiting resistor...  have some greens that were fine with ~50k. I only use led's for visual reference. I visually test each led for it's needed CLR.

dave

That's good info Dave.  I always find myself taming the brightness of LEDs.  I wonder the difference between the "low current" and using "high brightness" with a larger CLR?  Also wondering how the low current versions sound in led clipping circuits like the Boneyard/Plexitone/Plexidrive etc...  Perhaps there is no difference, but only one way to find out!

[davent]

Mark Hammer's idea for an LED tester, switch puts another 10k resistor in series so 24 steps, pretty much covers them all.