splitting a dual opamp to two discrete opamps....

Started by pinkjimiphoton, March 04, 2019, 10:57:38 AM

Previous topic - Next topic

pinkjimiphoton

is this worthy of exploring? i was thinking, if ya took a circuit that uses say, a 4558 and split it to two 741's you could probably add more tonal shaping elements, plus lets ya play with the feedback loop and tone more, wouldn't it? or is it a waste of time?

just wondering if being able to mess with the gain and tone of both stages individually could make for a more versatile kind of circuit.
  • SUPPORTER
"When the power of love overcomes the love of power the world will know peace."
Slava Ukraini!
"try whacking the bejesus outta it and see if it works again"....
~Jack Darr

Mark Hammer

#1
If the intent is to take advantage of the (potentially) unique properties of a given single op-amp, sure, why not.  But if not, then there is no real advantage.

For some things, though, it can be worthwhile to split, say, a quad op-amp into a pair of duals.  That lets you use a low-current dual for an LFO and do what is required for deticking, instead of having the entire 4 op-amps share the same power.

GibsonGM

Quote from: Mark Hammer on March 04, 2019, 11:44:25 AM
If the intent is to take advantage of the (potentially) unique properties of a given single op-amp, sure, why not.  But if not, then there is no real advantage.

For some things, though, it can be worthwhile to split, say, a quad op-amp into a pair of duals.  That lets you use a low-current dual for an LFO and do what is required for deticking, instead of having the entire 4 op-amps share the same power.

I found this to be THE way to build the Easyvibe.  ZERO ticking...the LFO is literally 3" away from the main PCB inside the wah shell!
  • SUPPORTER
MXR Dist +, TS9/808, Easyvibe, Big Muff Pi, Blues Breaker, Guv'nor.  MOSFace, MOS Boost,  BJT boosts - LPB-2, buffers, Phuncgnosis, FF, Orange Sunshine & others, Bazz Fuss, Tonemender, Little Gem, Orange Squeezer, Ruby Tuby, filters, octaves, trems...

amptramp

It is also worthwhile if you intend to use an offset null function because this is usually deleted in dual and quad op amps.  For AC amplification stages, this usually is not necessary unless you are using very high gains but if you have DC-coupled stages like precision rectifiers, this may be a worthwhile addition.

bluebunny

Other than the couple of bona fide examples mentioned above, the electrons aren't going to know whether they're whizzing around in one piece of black plastic or two.   ;)
  • SUPPORTER
Ohm's Law - much like Coles Law, but with less cabbage...

highwater

Unusual Applications for Op Amps (pdf)

There are a few things in there that won't work with a dual, not even the 14-pin ones that still have compensation and/or offset-null pins.
"I had an unfortunate combination of a very high-end medium-size system, with a "low price" phono preamp (external; this was the decade when phono was obsolete)."
- PRR

pinkjimiphoton

  • SUPPORTER
"When the power of love overcomes the love of power the world will know peace."
Slava Ukraini!
"try whacking the bejesus outta it and see if it works again"....
~Jack Darr