tremulus lune with tl074

[vacuumdust]

    I've built a few of these but not for years.  I'm going through my parts and i have everything to build one but no dual op amps.  Only some quads (tlo74).  I did a layout with the tl074 before i asked myself why this circuit wasn't designed with a single quad in the first place.  Am i asking for trouble with the whole ticking problem?  My guess is the two duals were chosen to keep the lfo away from the gain stage??  Anybody else tried this?  I could use use two tl074s i suppose and just leave half of each unused...I would have to tie the noninverting ins to outputs and ground the inverting ins on the unused sections correct?  sorry for the rambling question.  I realise I could just buy two duals but i want this finished soon.  THANKS

[pinkjimiphoton]

i'm not sure, but i BELIEVE you need to keep them separate so they are decoupled and don't tick.

[darron]

different opamps for different jobs.

the LFO opamp should ideally be a low current power amplifier such as a lm358. low current helps out (less draw, less tick to pull down the line). don't forget the LFO opamp is also actually POWERING the LED (and maybe a seconds rate LED). i think i read that with this much current draw and using opamps this way can sometimes latch them up (decades?) down the track. you could also use an emitter follower stage i guess to take the output of the LFO and power the LED.

the TL07x is just for hifi signal processing.




then finally, as said, having them in the same chip MAY encourage the LFO ticking to bleed through.