Who else besides me would like to see a push pull MOSFET final in the JAT EZ? Hmm, So, John, how many up votes will it take to make a MOSFET final happen?
When uA709 needed some diode addition to protect it against latch-up and when uA741 corrected that plus added internal frequency compensation, I found that both specified a minimum load resistance of 2 kilo-ohm. That was the "industry standard" for years after. Also, it was not only the output, the input common mode range was a limiting factor. Eventually we got rail-rail input or rail-rail output chips and finally chips that combined both features. However, most of them continued for quite some time to be limited to supply voltages good for 5 V use. But the chip prices have gone precipitously down since the uA741 introduction while various performance numbers have improved. In the old days, magazine articles used to publish their own evaluations including such as Price per Performance. As to voltage -- I still worry about my op amp characteristics and occasionally need to go back to my stash of (obsolete) LM343 that offers +/- 30 V power supply rating. In most other situations, and especially audio or other low noise requirements.my favorites have been and continue to be the OP27 or OP37 genre, available from multiple manufacturers due to wide cross licensing.
I am impressed of the NJM4556. I think it is another good candidate for a 30 Ohm stereo headphone amplifer delivering 0.5 V output voltage allready at a power supply voltage of +/- 3 V. It consumes a relatively high quiescent current of 9 to 12 mA and it has twice the input noise of the LM4562, so it is not well suited for phono preamps. The NJM is also capable to operate 30 Ohm headphones in class A mode up to a quiescent current of about 50 mA (with a suitable JFET between the output and the negativ power rail). The power supply voltage should be limited to +/- 6 V in this case, especially if it operates in stereo mode with both internal opamps.
Hello John, I see you check out Cool Dude Clem, like your channel, one of my oldest subscriptions. Great information as always. I hope you and your family, Brother, are all doing well. The voltage divider to the Non-Inverting input, with filter cap from 4.7 to 10 mF works good to power op-amp from a single supply rail. Voltage divider resistors from 10 to 100K. Glad your still doing videos, I have learned a great deal. After 9 days of forest fire smoke starting Labor Day, Sept 7th, the air has been clear and have had some welcome rain. Closest fire to me was 10-15 miles, nothing in immediate area. All the best from Oregon, Cass.
Hi John, thanks for the comparison of OPamps under load. I would say, that the most OPamps dont like a load under 600 ohm (resistive) due to the limited thermal conditions in the chip, especially when used with a higher supplyvoltage. The data sheet tells that the duration of output shortcut is unlimited, but there is no protection of overheat in regular chips.
It is like those who use a 5 volt regulator IC with a 25v input voltage and complain why the chip gets so hot even with small loads. Thermal design must be considered.
Cool vid! I'm always swapping Op-Amps in and out of my audio gear, just for curiosity mainly. I'm sure you know this but, those Op-Amps are garbage by today's standards. Just from Ti alone you have: the OPA627, OPA827, OPA1612, OPA1620, OPA1655, to say the least. Then if you want "high current"... you can have the dual channel LME49726 with 350 mA or the single channel LME49600 with 250 mA!
what is your best for audio in a dac? i want perfect square wav rendering (band limited to 20-25khz).. no crosstalk, low noise, low distortion etc.. maybe stable with some small DC offset (can it clean DC or you need cap to clean it?)
I really like pcb-rnd for doing pcb layout and was using geda for schematic capture but I moved to lepton-eda which is more stable but file format compatible.
strange... For my ears TL072 on high pass filter sound better than more chips i tested( TL082, NE5532P, YG4558, JRC4558D, RC4558, BA4560, JRC4565D)...And for subwoofer/ low frequency JRC4558D and TL082
Idk what 4.5 mhz means on an rca ca3240e. Would these chips work properly in a distortion pedal I have compared to other non 4.5 mhz op amps in the same class?
Thanks for the video - very educative! :) But I am not sure about the current calculations at the end? Should you take the RMS voltage, e.g. for the NE5532 10.8Vpp => 3.82Vrms => 38.2mA with 100Ohm load? That will also make the NJM4556 79.9mA which fits a bit more the datasheet :)
Yes that would make sense but the signal was not a sine wave due to the clipped tops. Current limit circuits will limit on some max level and I wanted to see what that was. Outside of audio, opamps are used for DC and non sinusoidal waveforms so it is useful to see where current limit kicks in.
No, John is quite right. If your opamp is clipping solidly at 10.8Vpp, then it is almost certainly swinging 5.4V each side of ground. Into a 100R load, that is exactly 54mA, which is clearly the current limit built-in to the output stage.
I was using the LME49710 but when they discontinued it I had to switch to the much more expensive LT1037 and now I am on the OPA1611. I know a lot of people like the ADA797 but some of it's other limitations made it less attractive to me.
The OPA1611 is fine if you have a low source impedance. The AD797 also, but it needs a compex compensation compensationnetwork. I also use the OPA627 or the OPA827 depending on the application.
@@ralfstocker7742 Yea I work in a hearing research lab so we have PXI chassis with multiple 24bit delta sigma converters. Our engineering department shares one and we have a number of HP DSA's. (I actually have a pair of HP 35665A's in my apartment) The rest of the opamps are not "unsuitable" it's just that source impedance, input offset, and etc can be wrong for a given part.
@@johnyang799 I thought about that but honestly time had marched on. You are right the wording "had to switch" was rather over stating it but we wanted to see if we could get a lower noise floor with something newer.
@@christophschuermann6512 I was aware of the OPA627 and it's cousin the OPA637 which I had used in some high speed current sources. The OPA827 I had never seen before. How have you liked it and what were you doing with it?
Have you done a video on your pilot signal. I just learned to get my oscilloscope to measure fft but it's hard to interoperate without that pilot signal as a 1% reference
John, for FUTURE CHALLENGE I would like to suggest to you to try to build up and test a circlotron power amplifier. They are very simply designed and called super symmetric and highly linear with very low THD+N. The challenge of these amplifiers is their floating dual power supply (but this can be simulated by two Li-Ion batteries or well separated lab power supplies for the first tests). ibb.co/cFKb74q (I think the connecting points for the feedback resistors must be switched directly to the P1- and P2- points).
If you are still looking for a collaboration on the project you want to have boards made for you should talk to Paul over at Learnelectronics, he’s a great guy that has made boards for many projects.
![The Wall Song ร้องข้ามกำแพง | EP.213 | กรีน อัษฎาพร | 3 ต.ค. 67 [1/5]](http://i.ytimg.com/vi/3KrlLbCsadI/mqdefault.jpg)
Who else besides me would like to see a push pull MOSFET final in the JAT EZ?
Hmm, So, John, how many up votes will it take to make a MOSFET final happen?
Me 👍
Me, of course
Every video nice and addictive
As always - Great video John!
When uA709 needed some diode addition to protect it against latch-up and when uA741 corrected that plus added internal frequency compensation, I found that both specified a minimum load resistance of 2 kilo-ohm. That was the "industry standard" for years after. Also, it was not only the output, the input common mode range was a limiting factor. Eventually we got rail-rail input or rail-rail output chips and finally chips that combined both features. However, most of them continued for quite some time to be limited to supply voltages good for 5 V use. But the chip prices have gone precipitously down since the uA741 introduction while various performance numbers have improved. In the old days, magazine articles used to publish their own evaluations including such as Price per Performance. As to voltage -- I still worry about my op amp characteristics and occasionally need to go back to my stash of (obsolete) LM343 that offers +/- 30 V power supply rating. In most other situations, and especially audio or other low noise requirements.my favorites have been and continue to be the OP27 or OP37 genre, available from multiple manufacturers due to wide cross licensing.
You always bring me the video I want.. great work 🙏 Thank you
Very good ....tutorial ...... and ...i like your cat...very nice...
I am impressed of the NJM4556. I think it is another good candidate for a 30 Ohm stereo headphone amplifer delivering 0.5 V output voltage allready at a power supply voltage of +/- 3 V. It consumes a relatively high quiescent current of 9 to 12 mA and it has twice the input noise of the LM4562, so it is not well suited for phono preamps. The NJM is also capable to operate 30 Ohm headphones in class A mode up to a quiescent current of about 50 mA (with a suitable JFET between the output and the negativ power rail). The power supply voltage should be limited to +/- 6 V in this case, especially if it operates in stereo mode with both internal opamps.
NJM4556 has been used in Objective O2 HPA. Absolutely gorgeous, able to drive virtually every can.
Hello John, I see you check out Cool Dude Clem, like your channel, one of my oldest subscriptions. Great information as always. I hope you and your family, Brother, are all doing well. The voltage divider to the Non-Inverting input, with filter cap from 4.7 to 10 mF works good to power op-amp from a single supply rail. Voltage divider resistors from 10 to 100K. Glad your still doing videos, I have learned a great deal. After 9 days of forest fire smoke starting Labor Day, Sept 7th, the air has been clear and have had some welcome rain. Closest fire to me was 10-15 miles, nothing in immediate area. All the best from Oregon, Cass.
John knows what he's talking about, though
Very good video as always, keep up!
That cat is like "dude, you woke me up ... go away!"
Hi John, thanks for the comparison of OPamps under load. I would say, that the most OPamps dont like a load under 600 ohm (resistive) due to the limited thermal conditions in the chip, especially when used with a higher supplyvoltage. The data sheet tells that the duration of output shortcut is unlimited, but there is no protection of overheat in regular chips.
It is like those who use a 5 volt regulator IC with a 25v input voltage and complain why the chip gets so hot even with small loads. Thermal design must be considered.
Cool vid! I'm always swapping Op-Amps in and out of my audio gear, just for curiosity mainly. I'm sure you know this but, those Op-Amps are garbage by today's standards. Just from Ti alone you have: the OPA627, OPA827, OPA1612, OPA1620, OPA1655, to say the least. Then if you want "high current"... you can have the
dual channel LME49726 with 350 mA or the
single channel LME49600 with 250 mA!
what is your best for audio in a dac? i want perfect square wav rendering (band limited to 20-25khz).. no crosstalk, low noise, low distortion etc..
maybe stable with some small DC offset (can it clean DC or you need cap to clean it?)
I really like pcb-rnd for doing pcb layout and was using geda for schematic capture but I moved to lepton-eda which is more stable but file format compatible.
5532 = 5nV/sqrt Hz. Nowadays I use OPA1678, the rail to rail is much better. Low noise opamp not supposed to load below 1k.
strange... For my ears TL072 on high pass filter sound better than more chips i tested( TL082, NE5532P, YG4558, JRC4558D, RC4558, BA4560, JRC4565D)...And for subwoofer/ low frequency JRC4558D and TL082
Idk what 4.5 mhz means on an rca ca3240e. Would these chips work properly in a distortion pedal I have compared to other non 4.5 mhz op amps in the same class?
problema é a resposta de frequencia - o TL 072 ganha quando temos 8 vac out - até 100khz responde melhor que o 4558/1458/5532
Thanks for the video - very educative! :)
But I am not sure about the current calculations at the end? Should you take the RMS voltage, e.g. for the NE5532 10.8Vpp => 3.82Vrms => 38.2mA with 100Ohm load? That will also make the NJM4556 79.9mA which fits a bit more the datasheet :)
Yes that would make sense but the signal was not a sine wave due to the clipped tops. Current limit circuits will limit on some max level and I wanted to see what that was. Outside of audio, opamps are used for DC and non sinusoidal waveforms so it is useful to see where current limit kicks in.
No, John is quite right. If your opamp is clipping solidly at 10.8Vpp, then it is almost certainly swinging 5.4V each side of ground. Into a 100R load, that is exactly 54mA, which is clearly the current limit built-in to the output stage.
lmfao i had to turn the captions on at the end of the video because i thought he called his sleeping cat the N-word
I was using the LME49710 but when they discontinued it I had to switch to the much more expensive LT1037 and now I am on the OPA1611. I know a lot of people like the ADA797 but some of it's other limitations made it less attractive to me.
Just use one side of lm4562.. And leave the other channel grounded input unity gain buffer.
The OPA1611 is fine if you have a low source impedance. The AD797 also, but it needs a compex compensation compensationnetwork. I also use the OPA627 or the OPA827 depending on the application.
@@ralfstocker7742 Yea I work in a hearing research lab so we have PXI chassis with multiple 24bit delta sigma converters. Our engineering department shares one and we have a number of HP DSA's. (I actually have a pair of HP 35665A's in my apartment) The rest of the opamps are not "unsuitable" it's just that source impedance, input offset, and etc can be wrong for a given part.
@@johnyang799 I thought about that but honestly time had marched on. You are right the wording "had to switch" was rather over stating it but we wanted to see if we could get a lower noise floor with something newer.
@@christophschuermann6512 I was aware of the OPA627 and it's cousin the OPA637 which I had used in some high speed current sources. The OPA827 I had never seen before. How have you liked it and what were you doing with it?
Would you consider replacing the 5532 in your preamp box with a 4556?
what about the NE5532A ???
@@garygranato9164 he has a 5532 in the preamp box already and I also built his box with a 5532, I was just looking at the current of the 4556
@@raymondheath7668
hi ray, i believe the NE5532 and the NE5532A are slightly different. but re- current, i wouldnt know because i'm noob to diy audio.
You don't need that much current. Just get ne5532 or lm4562.
4556 is meant for high current. 5532 is meant for low noise low thd.
Have you done a video on your pilot signal. I just learned to get my oscilloscope to measure fft but it's hard to interoperate without that pilot signal as a 1% reference
He has one.
@@AstrosElectronicsLab found it not under pilot signal. Ty
John, for FUTURE CHALLENGE I would like to suggest to you to try to build up and test a circlotron power amplifier. They are very simply designed and called super symmetric and highly linear with very low THD+N. The challenge of these amplifiers is their floating dual power supply (but this can be simulated by two Li-Ion batteries or well separated lab power supplies for the first tests). ibb.co/cFKb74q (I think the connecting points for the feedback resistors must be switched directly to the P1- and P2- points).
what's is ur opinion about Cmoybb headphone preamp/amp
If you are still looking for a collaboration on the project you want to have boards made for you should talk to Paul over at Learnelectronics, he’s a great guy that has made boards for many projects.
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what do you think about tl082 ?
I remember that's cheap version of tl072
@@springrollwang4441 Not necessarily. One is optimized for DC one is for AC.
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