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4580 Op-amp?

Started by MrStab, March 04, 2017, 09:26:41 AM

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MrStab

Hi guys,

I've been looking over the datasheet, but I'm just looking for some conjecture here: has anyone used the 4580 IC in a clean circuit and would you consider it fine for such purposes?

i ask because i need 4 dual op-amps in a SIP package, but forgot i'd run out of NJM072BL's (SIP version of TL072), and i can't source them locally for a reasonable price. also, the customer is very particular about their sound and in my own experience, the similar 4558's don't sound too great in filters compared to, say, the TL072 or 5532. i mean they do the job and a lot of the time people wouldn't notice with guitar work, but even though they both hover around the "transparency" line, i feel the TL0* series is a tiny bit closer to it on A/B comparison.

the circuit is 2x Multiple Feedback Loop filters added to the signal with differential amps. input to this is only 10k, so the BJT inputs of the 4580 shouldn't be a problem.

cheers for any opinions! or if anyone knows a decent UK source of NJM072BL (Mouser doesn't count), i'd love to know.
Recovered guitar player.
Electronics manufacturer.

anotherjim

Should be good. Don't Tech21 use the 4580 to drive XLR out in their D.I. pedals? And that from 9v, so headroom should be ok.
I've also found them in the audio path of consumer stuff like DVD players. I've got a few pulls from that source, but not got around to using them in anything.
I've a suspicion that like the NE5532, the 4580 is best with low source impedance - which you've already noticed.


J0K3RX

Wampler uses them in nearly all of his pedals that have opamps...
Doesn't matter what you did to get it... If it sounds good, then it is good!

MrStab

Thanks guys, if Wampler rely on em so much and Tech21 use it for balanced outputs then surely they must be decent enough.

I get the vague impression that they're purpose-built "upgrades" for the 4558, in the same way the TLE2072 is to the TL072, would I be correct with that assumption?

I can't find noise rating in the same nV/Hz format as the 4558, but that's something I'll have read up on to figure out. I'd imagine it's more than low enough.

Sent from my Vodafone Smart ultra 6 using Tapatalk

Recovered guitar player.
Electronics manufacturer.

MrStab

If the RC4580 datasheet is anything to go by then slightly less noise, slightly higher output swing, significantly faster slew rate and about double the supply current of the 4558. Seems not bad, then.

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Recovered guitar player.
Electronics manufacturer.

PRR

If you read the puff-sheet, 4580 is excellent for all audio!

It IS a very good audio chip for almost all purposes.

The only place I would fret (try both 4580 and TL072) is a guitar input. Very high-Z low-level nodes, the TL072 is known-good, the 4580 input current hiss is not specified and surely non-negligible. A rough guess says it may not be bad at guitar impedance, but only a guess.
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Elijah-Baley

Quote from: MrStab on March 05, 2017, 11:21:46 AM
If the RC4580 datasheet is anything to go by then slightly less noise, slightly higher output swing, significantly faster slew rate and about double the supply current of the 4558. Seems not bad, then.

Sent from my Vodafone Smart ultra 6 using Tapatalk

I have a question, please. I'm building a Wampler Triple Wreck, and the layout I'm following has a quad op-amp TL074 and a dual TL072.
I see that sometime the Triple Wreck hasn't much output, and I'm wondering if I can replace this two ICs and get more volume, just in case. In particular the TL072 with a 4580.
Thanks.
«There is something even higher than the justice which you have been filled with. There is a human impulse known as mercy, a human act known as forgiveness.»
Elijah Baley in Isaac Asimov's The Cave Of Steel

PRR

Op-amps give the gain set by EXternal parts (usually the resistors).

So opamp swap won't change gain.
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Elijah-Baley

Thank you. ;)
It makes sense, but you know, I read this thing somewhere.
«There is something even higher than the justice which you have been filled with. There is a human impulse known as mercy, a human act known as forgiveness.»
Elijah Baley in Isaac Asimov's The Cave Of Steel

anotherjim

Circuit I saw...
Starts out boosting then clipping/limiting with diodes -  so it's not a huge signal. Then a lossy tone stack. Then a fixed filter and then a lot of make up gain.
If you heard of low output level with some peoples builds, I suspect...

Someone made an error in their resistors values.

Trying to drive a line input - a lot of Wampler pedals seem to have fairly high output impedance, which will lose significant level driving a 10k input. Although it is a kind of "amp sound" box, they are, I think, made for driving a clean high impedance guitar amp channel - not as a complete amp sim/D.I. like a Sansamp or some ROG projects.



Elijah-Baley

Thank you, anotherjim.
I just built the whole circuit (no boost) of the Triple Wreck. It is out of the box and tested with clip, and the pots hasn't the knobs, so it is a bit difficult to see the "position" of the pots, but seems to me the amount of the volume is pretty ok.
In case I need help I'll write a new topic, but I am quite optimistic. ;)
«There is something even higher than the justice which you have been filled with. There is a human impulse known as mercy, a human act known as forgiveness.»
Elijah Baley in Isaac Asimov's The Cave Of Steel