njm4556 works best with headphones over 150 ohms that is why you have a series resistor of 150 ohms .Two circuits in parallel(the whole circuit in parallel , not just the op-amps with only one set of resistors) might do well as you can put only 62 ohms on each op-amp output summed in series with the headphones..
My small review on a few op amp’s:
To review these op amp’s I have used self made DAC based on AK4495, fully modified Class A power amp Sony F770ES, self made speakers with Accuton midwoofers and beryllium tweeters.
My long time favourite was AD797BR, because is has an accurate-correct sound. It does not have any colorations or artifacts. The sound is clean and open.
Bass is deep and clean. Midrange is very neutral and transparent. All the instruments sound the way they originally are. Highs are one of the best you can have from a operational amplifier. Has that pleasant sparkle I like. Soundstage is wide. Background is black.
Muses 03 has a slower sound. There is less amount of sub bass and it is not as deep as it is on AD797. It is a little bit flat and boomy. Midbass lacks speed and energy.
Midrange sounds much more warmer and more beautiful, but at a cost of changing the layering of sounds. Voices are pushed forward and the instruments are pulled back. Definitely not a natural sound. I would describe it as a very “high end’ish” sound. It gives you that “wow” factor at the beginning, but later you understand that it is not a real sound.
Highs are a little recessed.
Overal sound is calm and lacking liveliness.
Sparkos Labs ss3602 compared to AD797 is a little bit more detailed and has more bass impact. But it has more “synthetic” and cold midrange, which really destroys music for me. But overall it is pretty similar to AD797.
For Burson single Vivid I think that the name “Vivid” really represents the sound signature of this op amp. I would say that it has a very developed and polished sound without any artifacts. It is also pretty similar to AD797, but it has more bass and midbass which gives a feeling of fuller sound. Midrange is cleaner, more sweet and lively, has more air. Highs are almost the same on both, which are very accurate.
I also want to mention that I don’t like most of the Burr Brown op amp’s because of their highly messed up sound signature with balance issues, incorrect layering and other imperfections. For me most of them are slow and not detailed enough. I would say that they suit only for a lower level audio gear…
To review these op amp’s I have used self made DAC based on AK4495, fully modified Class A power amp Sony F770ES, self made speakers with Accuton midwoofers and beryllium tweeters.
My long time favourite was AD797BR, because is has an accurate-correct sound. It does not have any colorations or artifacts. The sound is clean and open.
Bass is deep and clean. Midrange is very neutral and transparent. All the instruments sound the way they originally are. Highs are one of the best you can have from a operational amplifier. Has that pleasant sparkle I like. Soundstage is wide. Background is black.
Muses 03 has a slower sound. There is less amount of sub bass and it is not as deep as it is on AD797. It is a little bit flat and boomy. Midbass lacks speed and energy.
Midrange sounds much more warmer and more beautiful, but at a cost of changing the layering of sounds. Voices are pushed forward and the instruments are pulled back. Definitely not a natural sound. I would describe it as a very “high end’ish” sound. It gives you that “wow” factor at the beginning, but later you understand that it is not a real sound.
Highs are a little recessed.
Overal sound is calm and lacking liveliness.
Sparkos Labs ss3602 compared to AD797 is a little bit more detailed and has more bass impact. But it has more “synthetic” and cold midrange, which really destroys music for me. But overall it is pretty similar to AD797.
For Burson single Vivid I think that the name “Vivid” really represents the sound signature of this op amp. I would say that it has a very developed and polished sound without any artifacts. It is also pretty similar to AD797, but it has more bass and midbass which gives a feeling of fuller sound. Midrange is cleaner, more sweet and lively, has more air. Highs are almost the same on both, which are very accurate.
I also want to mention that I don’t like most of the Burr Brown op amp’s because of their highly messed up sound signature with balance issues, incorrect layering and other imperfections. For me most of them are slow and not detailed enough. I would say that they suit only for a lower level audio gear…
Could be from a production by Matsushita for Analog Devices. It is not uncommon in this industry to have basics like wafer´s made by another company.
Such a chip is nothing secret, you can open and copy it. If another company has free capacity to produce them, maybe even cheaper than AD, that is no problem, just a commercial decision.
Such a chip is nothing secret, you can open and copy it. If another company has free capacity to produce them, maybe even cheaper than AD, that is no problem, just a commercial decision.
I'm coming very late to op-amps after building with tubes for many years. I looked for a solution to adding gain to a 2 stage DHT 300b amp and op-amps seem to be an excellent way to add gain for a low level signal. I can only offer some subjective impressions of the few 8 pin DIP duals I've tried so far. This is in a cheap chi-fi NE5532 board with single supply driven from my bench supply, but cheap as it is it seems to be well thought out and made. All SMD except the socketed op-amp.
NE5532 - baseline. Neutral, nothing special but generally good.
OPA2228 - around the same level of sound as NE5532. Smooth, low distortion, good vocal timbre, lacks ultra transparency. Musical. A bit down in extreme treble. Less detailed and airy than LM4562, less inner detail in orchestral textures, can sound a bit duller, not so involving, less punch.
LM4562
Very detailed, airy highs, transparent. Strings can be a little thin. Plenty of punch in the bass. Overall sound is similar to the OPA2134 and LM6172, which is to say more transparency and more involving than the OPA2228
OPA2134
FET input. Very neutral, does everything well, smooth, good voices, even frequency response, good tone. Overall very nice. Versus LM4562 maybe smoother, more balanced FR, less extreme highs and air, but highs nicely there. Could live with this one.
LM6172
Very similar sound to OPA2134 plus just a tiny bit more transparent. Neutral, does everything well, smooth, good voices, even frequency response, good tone. Not too different from LM4562. Maybe smoother, more balanced FR, less extreme highs and air, but highs nicely there. High slew rate and would need to be checked for oscillation (I don't have the means). If correctly implemented this could be very good, but more fussy than OPA2134.
The last three are very close. It would need more listening to decide between them. I just used 8 pin DIP devices here, and by using a SOIC adapter some of the latest op-amps may exceed the ones tried here. These are all duals, no singles tried yet. For the input section of a tube amp I'm very encouraged by what I'm hearing. Neutral, transparent sound with good instrumental tone.
My AK4490 DAC has a socketed NE5532 in the output and I've tried swapping in an OPA2134 there. More detail certainly, though the NE5532 was a rather fuller sound. I'm not quite sure how to mix the two stages to get a sound that has all the detail but also a full and smooth sound. It would be good if I could increase the gain in the DAC itself but it's all SMD and I have no experience at all with that. As a beginner in op-amps I'm surprised at how good they can be at lower signal amplification. Tube builders can be a bit sniffy about op-amps but I'm a convert.
NE5532 - baseline. Neutral, nothing special but generally good.
OPA2228 - around the same level of sound as NE5532. Smooth, low distortion, good vocal timbre, lacks ultra transparency. Musical. A bit down in extreme treble. Less detailed and airy than LM4562, less inner detail in orchestral textures, can sound a bit duller, not so involving, less punch.
LM4562
Very detailed, airy highs, transparent. Strings can be a little thin. Plenty of punch in the bass. Overall sound is similar to the OPA2134 and LM6172, which is to say more transparency and more involving than the OPA2228
OPA2134
FET input. Very neutral, does everything well, smooth, good voices, even frequency response, good tone. Overall very nice. Versus LM4562 maybe smoother, more balanced FR, less extreme highs and air, but highs nicely there. Could live with this one.
LM6172
Very similar sound to OPA2134 plus just a tiny bit more transparent. Neutral, does everything well, smooth, good voices, even frequency response, good tone. Not too different from LM4562. Maybe smoother, more balanced FR, less extreme highs and air, but highs nicely there. High slew rate and would need to be checked for oscillation (I don't have the means). If correctly implemented this could be very good, but more fussy than OPA2134.
The last three are very close. It would need more listening to decide between them. I just used 8 pin DIP devices here, and by using a SOIC adapter some of the latest op-amps may exceed the ones tried here. These are all duals, no singles tried yet. For the input section of a tube amp I'm very encouraged by what I'm hearing. Neutral, transparent sound with good instrumental tone.
My AK4490 DAC has a socketed NE5532 in the output and I've tried swapping in an OPA2134 there. More detail certainly, though the NE5532 was a rather fuller sound. I'm not quite sure how to mix the two stages to get a sound that has all the detail but also a full and smooth sound. It would be good if I could increase the gain in the DAC itself but it's all SMD and I have no experience at all with that. As a beginner in op-amps I'm surprised at how good they can be at lower signal amplification. Tube builders can be a bit sniffy about op-amps but I'm a convert.
It is interesting reading all your comments 
If you like experimenting with opamps then it can be a fun exercise to go really 'bad' and try something like (LM)1458 which is similar to a dual 741. The ever popular 4558 is a bit better and seen in countless commercial gear.
Although we would never use these today it is instructive to actually listen to these and set markers down as to how you think they compare to state of the art offerings.
A genuine favourite of mine when it is used correctly is the TL072 with its FET input stage. This was the darling of the audio world a couple of decades ago. Try one in your DAC
If you like experimenting with opamps then it can be a fun exercise to go really 'bad' and try something like (LM)1458 which is similar to a dual 741. The ever popular 4558 is a bit better and seen in countless commercial gear.
Although we would never use these today it is instructive to actually listen to these and set markers down as to how you think they compare to state of the art offerings.
A genuine favourite of mine when it is used correctly is the TL072 with its FET input stage. This was the darling of the audio world a couple of decades ago. Try one in your DAC
Yes - I've read a lot of your posts and I'll get hold of a TL072. Slew rate is same as 5534. Should I get the CP or ACP version?
I put a NE5532AP back in the DAC - it's a smoother and fuller sound. I have a few NE5532s and the AP version was the most expensive, don't know if that means better.
With the OPA2134 the DAC was more detailed but the sound lacked body. The OPA2228 didn't sound good in the DAC, and was the least good in the op-amp gain stage. In the gain stage it'll probably be LM4562 or OPA2134 for now. But in terms of single op-amps I have some to try - LT1028, OP27, AD845 and NE5534.
I put a NE5532AP back in the DAC - it's a smoother and fuller sound. I have a few NE5532s and the AP version was the most expensive, don't know if that means better.
With the OPA2134 the DAC was more detailed but the sound lacked body. The OPA2228 didn't sound good in the DAC, and was the least good in the op-amp gain stage. In the gain stage it'll probably be LM4562 or OPA2134 for now. But in terms of single op-amps I have some to try - LT1028, OP27, AD845 and NE5534.
Last edited:
There are so many versions such as lead free, ceramic, plastic, extended temperature range, package quantity etc but all are electrically the same for our purposes. Just make certain you get the outline you want such as DIL rather than an SMD and always buy from reputable suppliers.
I think the only difference between CP and ACP is that ACP is lead free. Its all in the full pdf data sheet on pages 37 and 38:
https://www.ti.com/product/TL072
When something uses the NE5534 you need to be very careful to check how it is used because the 5534 is not unity gain stable and so the application may include extra parts connected to pins 8 and 5. Also the offset null adjustment may or may not be used and the configuration and parts used for offset null (preset value and method of connection) vary between opamps.
I think the only difference between CP and ACP is that ACP is lead free. Its all in the full pdf data sheet on pages 37 and 38:
https://www.ti.com/product/TL072
When something uses the NE5534 you need to be very careful to check how it is used because the 5534 is not unity gain stable and so the application may include extra parts connected to pins 8 and 5. Also the offset null adjustment may or may not be used and the configuration and parts used for offset null (preset value and method of connection) vary between opamps.
VERY important to limit its use. It is NOT to be used in driving anything below ~10KΩ, or in any noise-critical circuit. Overall, the OPA1642 is a MUCH better choice. But it IS more expensive and SOIC only.A genuine favourite of mine when it is used correctly is the TL072 with its FET input stage. This was the darling of the audio world a couple of decades ago. Try one in your DAC
Thanks mooly and dotneck...
The NE5532 in the AK4490 DAC output is driving the following op-amp (the stage we're talking about), which at present is a LM4562. What's the impedance the NE5532 sees into the LM4562? That would help my choice of devices. The LM4562 is driving a 4P1L tube with 100K on the input to ground.
I'm open to swapping op-amps in the DAC output if you can give suggestions for duals, preferably in DIP.
The NE5532 in the AK4490 DAC output is driving the following op-amp (the stage we're talking about), which at present is a LM4562. What's the impedance the NE5532 sees into the LM4562? That would help my choice of devices. The LM4562 is driving a 4P1L tube with 100K on the input to ground.
I'm open to swapping op-amps in the DAC output if you can give suggestions for duals, preferably in DIP.