Is there a popular source for a chart or some other form of tabulation that lists currently in production op amps that are JFET?
I'm interested in single supply op amps in general and hoping to find an overview describing their actual performance characteristics. Which has more bass, which has a hollow sound, which is the best all around performer etc.
I'm assuming it exists and just as likely on a popular site or purchasing source, but search results today through the most known search engines produce too many dead ends. Might even just be how I have phrased the searches.
I was hoping to find a simple way to locate JFET, BJT etc. granted BJT are surely the easiest to find.
I don't want to say "cheap" but obviously I'm looking for some JEFT O.A.'s that are reasonably priced compared to their BJT counterpart.
I'm interested in single supply op amps in general and hoping to find an overview describing their actual performance characteristics. Which has more bass, which has a hollow sound, which is the best all around performer etc.
I'm assuming it exists and just as likely on a popular site or purchasing source, but search results today through the most known search engines produce too many dead ends. Might even just be how I have phrased the searches.
I was hoping to find a simple way to locate JFET, BJT etc. granted BJT are surely the easiest to find.
I don't want to say "cheap" but obviously I'm looking for some JEFT O.A.'s that are reasonably priced compared to their BJT counterpart.
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Those are not properties of an opamp.
The frequency response is determined by the feedback network, not the opamp - so all opamps have the same bass, given the same feedback network... That's the entire point of using them, the behaviour is determined by the passive components, normally to very high precision.
The properties that do vary are upper frequency, distortion, voltage noise, current noise, slew-rate, power consumption, input impedance, open-loop output impedance, load-driving ability, cost, supply voltage range, rail-to-rail/single supply, EMI-sensitivity, PSRR, CMRR, input bias current, input offset voltage, decoupling requirements.
To find lists of devices use the parametric search engines at the well known suppliers like Digi-key, you can search for many parameters, or at individual manufacturers' websites (often have more detailed search facilities). There are probably many 1000's of JFET opamps currently in production so a single chart isn't really the way to go, many of them are obscure and expensive, parametric search can really help find good options.
I'll take that nonsense as a no?
I'm asking about single supply and FET input as opposed to dual supply and BJT input.
What I listed are most certainly properties of op amps regarding performance traits.
I wasn't asking for a human data sheet.
The NE5532 BJT input is known for it's all around frequency evenness and good bass(I probably have 200 ATM.
The OPA2604 is known for having good bass(I have several of these and bundle on the way in the mail)
Some are known for being hollow, shrill(JRC4558), thin and ratty highs and so forth.
Believe it or not, I have a formal college education in electrical/electronics engineering.
I'm asking about single supply and FET input as opposed to dual supply and BJT input.
What I listed are most certainly properties of op amps regarding performance traits.
I wasn't asking for a human data sheet.
The NE5532 BJT input is known for it's all around frequency evenness and good bass(I probably have 200 ATM.
The OPA2604 is known for having good bass(I have several of these and bundle on the way in the mail)
Some are known for being hollow, shrill(JRC4558), thin and ratty highs and so forth.
Believe it or not, I have a formal college education in electrical/electronics engineering.
That's alas myth rather than fact. Many people don't understand what opamps do and imagine all sorts that's counter-factual as a result. Given a basic minimum specification able to handle the audio band accurately they can all behave the same for a signal, modulo small variations in distortion and noise-level, since its the circuit topology that determines the behaviour.
JFET opamps at Digi-key, 1800 hits:https://www.digikey.co.uk/en/produc...A2iAMywBMADLQOwgC6hADgC5QgDKHATgEsAdgHMQAXylA
Well Mark, you want to help a guy understand the facts and you get ridiculed.
No good deed goes unpunished.😎
Jan
No good deed goes unpunished.😎
Jan
It's not a myth, but this is the typical behavior here just like I recall going back as far as 20 years ago.
I have a formal, college education in electrical/electronics engineering and also recall those tend to be in very short supply on DIY forums, and this one is no exception.
This forum, like many design and engineering audio related forums, will be filled with posts talking about traits of popular op amps.
I have probably a few hundred sitting in my electronics lab.
Some I have had for ohhhh 20 years.
Some have better bass, hollow texture and so forth but it's not a drop it in and you miraculously have 6dB of boost in the lows.
There's no reason to be rude and condescending.
You assumed I'm a halfwit and seized an opportunity to be snobs.
Absolutely nothing about this forum has changed.
I have a formal, college education in electrical/electronics engineering and also recall those tend to be in very short supply on DIY forums, and this one is no exception.
This forum, like many design and engineering audio related forums, will be filled with posts talking about traits of popular op amps.
I have probably a few hundred sitting in my electronics lab.
Some I have had for ohhhh 20 years.
Some have better bass, hollow texture and so forth but it's not a drop it in and you miraculously have 6dB of boost in the lows.
There's no reason to be rude and condescending.
You assumed I'm a halfwit and seized an opportunity to be snobs.
Absolutely nothing about this forum has changed.
If you use DC coupling in the circuit, the bass response will be ruler flat down to DC.
You can change the opamp as much as you like but that will not change, it's a circuit property.
If you use AC coupling, it is the value of the coupling cap in combination with other circuit resistances
which determines at which frequency the bass response starts to roll of.
But also in this case, changing the opamp has no effect*.
Opamps cannot be used in audio without a feedback network.
It is the feedback network that determines the circuit behaviour.
A nice example is a RIAA preamp, where the required response shape is often created by modifying the feedback network,
not by changing the opamp, which would not work.
Opamps do differ of course, in noise performance, DC offset and drift, distortion, that sort of thing.
So it does pay to carefuly select your opamp for the intended purpose.
But modern opamps have so much loop gain up to high frequencies that even at the 20kHz audio frequency,
changing opamps has zero effect on the response shape at that end.
As far as frequency response is concerned, opamp changes don't do diddly.
Jan
* It is known that perception related issues may cause an apparent change in response to a listener.
But that is not based on any actual, physical changes in the reproduction response.
You can change the opamp as much as you like but that will not change, it's a circuit property.
If you use AC coupling, it is the value of the coupling cap in combination with other circuit resistances
which determines at which frequency the bass response starts to roll of.
But also in this case, changing the opamp has no effect*.
Opamps cannot be used in audio without a feedback network.
It is the feedback network that determines the circuit behaviour.
A nice example is a RIAA preamp, where the required response shape is often created by modifying the feedback network,
not by changing the opamp, which would not work.
Opamps do differ of course, in noise performance, DC offset and drift, distortion, that sort of thing.
So it does pay to carefuly select your opamp for the intended purpose.
But modern opamps have so much loop gain up to high frequencies that even at the 20kHz audio frequency,
changing opamps has zero effect on the response shape at that end.
As far as frequency response is concerned, opamp changes don't do diddly.
Jan
* It is known that perception related issues may cause an apparent change in response to a listener.
But that is not based on any actual, physical changes in the reproduction response.
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But Jan, they are talking about subjective impressions.
How can you (we) argue against that with objective parameters ?
😆
Patrick
How can you (we) argue against that with objective parameters ?
😆
Patrick
I don't know about you, but with a formal electronic engineering education I would not accept 'miraculously'.
I would get to the bottom of it.
Did you measure that 6dB change?
Jan
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Just to deescalate a little, Jmariner wrote he knows there are no miraculous changes of 6 dB in bass by changing the op amp.
Regarding single supply:
As long as you stay well away from the rails (which is advisable in audio) any op amp can be used with single supply, if i'm not mistaken.
You have received the best possible answers from a few of the most respected and knowledgeable people on this forum.
Don't dismiss that.
These people stick to facts, not to lip service or to what you would like to hear.
In addition here is a paper well worth reading that will fill a gap in your "formal, college education in electrical/electronics engineering".
Hugo
Don't dismiss that.
These people stick to facts, not to lip service or to what you would like to hear.
In addition here is a paper well worth reading that will fill a gap in your "formal, college education in electrical/electronics engineering".
Hugo
An engineer, especially with a formal education, does not describe electronic components in subjective terms, unless he has to describe the results of technical characteristics to someone with no understanding of electronics. The 4558 may result in "ratty highs", but here we say that it has a poor slew rate, and the output has cross-over distortion. If an op-amp lacks bass, it's because the circuit closed loop gain is too high, as might happen in a phono preamp. Most any op-amp will sound just fine if you understand it's limits and use it accordingly. These subjective sound characteristics are mostly about the circuit they are used in, and using a device suited for that application. And single supply op-amps are not generally audio op-amps. Audio op-amps operate in the middle of the supply rails because audio is an AC signal. Mixing ground and the negative rail is a cheap and nasty practice that results in noise and distortion problems. 20 years is nothing compared to the experts here at DIYA. I myself have about 50 years of experience.
Jan, yes, it's from ADI. Here is chapter 2:
There are more, search for "analogue devices chapter 3", 4, 5, ..
Hugo
There are more, search for "analogue devices chapter 3", 4, 5, ..
Hugo
@davidsrsb, you would think so, but at those high frequencies, the output voltages drop at the same rate, so that output current doesn't really increase.
Jan
Jan