Hi,
Looking for some guidance to replace the Red power indicator lamp on the front panel of a late grey model Quad 405-2 with a Blue one, possibly an LED. Having searched for component values and/or a wiring diagram of installation to modify to Blue there appears to be little information. Maybe other 405-2 owners have successfully fitted different coloured lamps and could offer their advice.
Many thanks,
David.
Looking for some guidance to replace the Red power indicator lamp on the front panel of a late grey model Quad 405-2 with a Blue one, possibly an LED. Having searched for component values and/or a wiring diagram of installation to modify to Blue there appears to be little information. Maybe other 405-2 owners have successfully fitted different coloured lamps and could offer their advice.
Many thanks,
David.
You can sub a blue LED for the red LED with no other changes. Be sure to observe polarity.
The intensity may not be the same, and then you can change the value of the series 2.7k
resistor to suit, with a higher value = dimmer.
The intensity may not be the same, and then you can change the value of the series 2.7k
resistor to suit, with a higher value = dimmer.
Seems this subject has part of a website all to itself.
Yellow LED,S were tried but did not look good ,a white LED was chosen but they are usually for illumination so at about 4V the current had to be reduced to 2V at 0,5ma to dim it down.
Its all about the series resistor Pioneer and the article was all about your late version -grey.
Yellow LED,S were tried but did not look good ,a white LED was chosen but they are usually for illumination so at about 4V the current had to be reduced to 2V at 0,5ma to dim it down.
Its all about the series resistor Pioneer and the article was all about your late version -grey.
Exactly what rayma said.
You might want to start with 10K or even 22K for the resistor though - modern LEDs are considerably more efficient (lm/w) than the 35+yr old part in there, and blue is garish anyway. You only want to know the amp is powered up, not read a newspaper by it at night (says the guy who did exactly this with a nice violet-hued led about 20yrs ago...)
You might want to start with 10K or even 22K for the resistor though - modern LEDs are considerably more efficient (lm/w) than the 35+yr old part in there, and blue is garish anyway. You only want to know the amp is powered up, not read a newspaper by it at night (says the guy who did exactly this with a nice violet-hued led about 20yrs ago...)
Thanks for all the responses. I`ve not seen the part of a website dedicated to Quad 405-2 LED sustitution, would you perhaps have a link to it ?
The 2.7K resistor can be changed to a 10 or 22K to find a suitably subtle Blue glow, I`m not looking to be able to read LP covers in the dark
.
The 2.7K resistor can be changed to a 10 or 22K to find a suitably subtle Blue glow, I`m not looking to be able to read LP covers in the dark
.
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Try 22k. As mentioned by others, modern LED are very, very bright by comparison. They need micro amps to look normal.
The phono stage on this pre-amp appears to be under the DISC selection. I'm cheating a little bit here by running a behringer pp400 into the AUX selection on this amp. This is since the phono stage sounds pretty dull/nasty to be honest. I think the module doesn't suit my cartridge properly. The quad pre-amps supposedly came with 3 modules for certain input sensitivities. The one I was given is unfortunately not a great match, but all in due time I will have that sorted!