anything better?
Hi Klaus and all,
I think, for most of the time, we are talking about two different things. Since the end of the 1970s until 1981 I worked part time as a music presenter and consequently got involved in the recording of music. At that time I was also a in DIY – not a fanatic but seriously involved designing my own systems from a scratch and these were active. In those times almost everything was discrete and, as it is today, speakers were the weakest link when reproduction of music was concerned.
One day we (I was not alone in this) decided to find out which speaker drivers available to us were most faithful in this respect. A panel of musicians was to tell us which are the most faithful reproducers. The reason for turning to musicians was obvious. Not because their hearing is the best (most young people have good hearing) but because they have well above the average musical memory and they can not only remember but also “produce” and “reproduce” music.
Very quickly we found out that we have to concentrate on improvised music in our tests. Reason for that was simple – only then the whole concentration was turned towards comparing live performance with reproduced sound rather than noting that this particular half note on C was not really …
The interesting part was that in some cases responses were inconsistent and that was leading to one conclusion, namely that there are notable differences between individual brain functionality when it comes to interpretation of what is heard through senses. In fact the same applies to interpreting info from all senses. Moreover, it does not apply only to interpreting music but everything.
Interestingly, there is also a great difference between the way female and male brains interpret exactly the same sentences and even words. When it comes to music women concentrate on the emotional associations and that is why they as customers (including hi-fi industry) are quite different than men. Anyway, the role of brain as final interpreter of what comes to it through senses and the way it prioritizes that information is generally not given proper attention by most.
Moreover, many brains which perceive differences between X and Y (and not all brains do) will not give a d… because their priorities (often subconscious) are somewhere else. So if we do something for ourselves than we (our brains) are the only judges of the result. If we work/produce for others we have to take into account not only their ability to tell apart X from Y or A from B but what of these constitute priorities for their brains. In that context it often appears that we can’t tell apart A from B.
To conclude, I think it is worth to notice sometimes that whatever comes to our consciousness is greatly influenced by working of our brains - and not only by signals from the outer world. And final very tricky question: “sounds great” or “most faithful reproduction”?
Cheers,
Hi Klaus and all,
I think, for most of the time, we are talking about two different things. Since the end of the 1970s until 1981 I worked part time as a music presenter and consequently got involved in the recording of music. At that time I was also a in DIY – not a fanatic but seriously involved designing my own systems from a scratch and these were active. In those times almost everything was discrete and, as it is today, speakers were the weakest link when reproduction of music was concerned.
One day we (I was not alone in this) decided to find out which speaker drivers available to us were most faithful in this respect. A panel of musicians was to tell us which are the most faithful reproducers. The reason for turning to musicians was obvious. Not because their hearing is the best (most young people have good hearing) but because they have well above the average musical memory and they can not only remember but also “produce” and “reproduce” music.
Very quickly we found out that we have to concentrate on improvised music in our tests. Reason for that was simple – only then the whole concentration was turned towards comparing live performance with reproduced sound rather than noting that this particular half note on C was not really …
The interesting part was that in some cases responses were inconsistent and that was leading to one conclusion, namely that there are notable differences between individual brain functionality when it comes to interpretation of what is heard through senses. In fact the same applies to interpreting info from all senses. Moreover, it does not apply only to interpreting music but everything.
Interestingly, there is also a great difference between the way female and male brains interpret exactly the same sentences and even words. When it comes to music women concentrate on the emotional associations and that is why they as customers (including hi-fi industry) are quite different than men. Anyway, the role of brain as final interpreter of what comes to it through senses and the way it prioritizes that information is generally not given proper attention by most.
Moreover, many brains which perceive differences between X and Y (and not all brains do) will not give a d… because their priorities (often subconscious) are somewhere else. So if we do something for ourselves than we (our brains) are the only judges of the result. If we work/produce for others we have to take into account not only their ability to tell apart X from Y or A from B but what of these constitute priorities for their brains. In that context it often appears that we can’t tell apart A from B.
To conclude, I think it is worth to notice sometimes that whatever comes to our consciousness is greatly influenced by working of our brains - and not only by signals from the outer world. And final very tricky question: “sounds great” or “most faithful reproduction”?
Cheers,
Hi janusz ,
Your explanation is great.
It is absolutely clear , that if our brain "believies" it should be so , sometimes it can even modify our senses.I have seen more than one example.One was the picture of face with inverted eyes.When you look at it , eyes look normal , because the brain detects an error and fixes it ... This does not work , if you reverse the picture.
It maight be much more common than we think.
Your explanation is great.
It is absolutely clear , that if our brain "believies" it should be so , sometimes it can even modify our senses.I have seen more than one example.One was the picture of face with inverted eyes.When you look at it , eyes look normal , because the brain detects an error and fixes it ... This does not work , if you reverse the picture.
It maight be much more common than we think.
I have done a brief (couple of hours) direct comparison of: NE5534, BE4558, TL072, OPA2228, OPA2134, OPA2604, OP275, module with 2x AD825 and THS4032 with pins to DIP8+tantal 1uF from pins 8 to 4. I was swapping them in analog part of modified Denon DCD-735.
If I would give 1 to 10 points regarding overall soud quality, the results would be like here:
NE5534, BE4558, TL072, OPA2228, OPA2134, OPA2604, OP275
- each of them less than 5 points 😱
AD825 - 6 points
... and the unsurpassable winner is: THS4032 - 9 or 10 points
It might be my own personal preference (but an other pair of ears said that it is surpassingly clear and wonderful sound as well) with 4032. It completely removes any harshness, violence, technically sounding higher middle tones, and giving perfectly clean sound.
You might be shocked by finding certain instruments and sounds you did not hear before from your discs, being unsure whether that is some kind of distortion, or a real sound that you weren't able to hear due to imperfect opamps before.
4032 brings so much natural sound that be prepared for immediate addiction !!!
P.S. author is with no relationship with TI.
P.S.2 if you are considering similar test, be aware that OPA2604 does not survive reversing for more than 3 seconds on +/- 5 Volts
If I would give 1 to 10 points regarding overall soud quality, the results would be like here:
NE5534, BE4558, TL072, OPA2228, OPA2134, OPA2604, OP275
- each of them less than 5 points 😱
AD825 - 6 points
... and the unsurpassable winner is: THS4032 - 9 or 10 points
It might be my own personal preference (but an other pair of ears said that it is surpassingly clear and wonderful sound as well) with 4032. It completely removes any harshness, violence, technically sounding higher middle tones, and giving perfectly clean sound.
You might be shocked by finding certain instruments and sounds you did not hear before from your discs, being unsure whether that is some kind of distortion, or a real sound that you weren't able to hear due to imperfect opamps before.
4032 brings so much natural sound that be prepared for immediate addiction !!!
P.S. author is with no relationship with TI.
P.S.2 if you are considering similar test, be aware that OPA2604 does not survive reversing for more than 3 seconds on +/- 5 Volts
Attachments
Hi Celestian,
so you only have one 2604 left then!
Is there any chance that the circuit you have inserted the opamps into has been optimised for the 4032?
Could the other opamps require different compensation and/or different decoupling and/or different pin connections and/or rail to rail incompatibility and/or different something else that your circuit is not providing.
I am VERY surprised that all others seem to perform so badly in comparison to 4032, suggesting that the comparison is not a true comparison at all.
so you only have one 2604 left then!
Is there any chance that the circuit you have inserted the opamps into has been optimised for the 4032?
Could the other opamps require different compensation and/or different decoupling and/or different pin connections and/or rail to rail incompatibility and/or different something else that your circuit is not providing.
I am VERY surprised that all others seem to perform so badly in comparison to 4032, suggesting that the comparison is not a true comparison at all.
Hi Celestian,
What supply voltage did you use for ths4032?
It draws quite large current and should be quite hot under +/-15V supply. And it's not unit gain stable.
What supply voltage did you use for ths4032?
It draws quite large current and should be quite hot under +/-15V supply. And it's not unit gain stable.
> ... and the unsurpassable winner is: THS4032 - 9 or 10 points
Suggest you try OPA1632.
Regards,
Patrick
Suggest you try OPA1632.
Regards,
Patrick
AndrewT: exactly, no more tests with 2604 for both channels simultaneously. I was also surprised with my results, believe me.
One thing i can think of as and "unfair" against others is that THS had the capacitor soldered directly on rail voltage pins.
I do not have schematic of Denon DCD-735, but output of the first opamp in the socket (they are all double opamps) is going directly (through some elyts though) to output cinch connectors while output of second opamp in the package is going to pins of DA converter (some kind of feedback ?).
Banana: supply voltage is +/- 5 Volts, I did not change anything else in analog circuits.
One thing i can think of as and "unfair" against others is that THS had the capacitor soldered directly on rail voltage pins.
I do not have schematic of Denon DCD-735, but output of the first opamp in the socket (they are all double opamps) is going directly (through some elyts though) to output cinch connectors while output of second opamp in the package is going to pins of DA converter (some kind of feedback ?).
Banana: supply voltage is +/- 5 Volts, I did not change anything else in analog circuits.
THS4032
Hi Celestian,
Good to see that others come to the conclusion that the THS4032 is an outstanding OpAmp.
But I would give it a more optimized circuit. You have to put 0,1 uf film cap very close from both supply pins to ground and also 100 - 200uf high quality lytics (Panasonic FC or better Rubycon ZL) also as close as possible from every supply pin to ground. Best is to do all this on a seperate little board, then you have the space to fit the extra resistors to give it the riquired gain. I have not tried to force the 4032 into class A, but it would be worth trying.
As a guide you can download the PDF of the evaluation board for the 4032.
With the proper implemantation it walks all over the OPA627.
Klaus
Hi Celestian,
Good to see that others come to the conclusion that the THS4032 is an outstanding OpAmp.
But I would give it a more optimized circuit. You have to put 0,1 uf film cap very close from both supply pins to ground and also 100 - 200uf high quality lytics (Panasonic FC or better Rubycon ZL) also as close as possible from every supply pin to ground. Best is to do all this on a seperate little board, then you have the space to fit the extra resistors to give it the riquired gain. I have not tried to force the 4032 into class A, but it would be worth trying.
As a guide you can download the PDF of the evaluation board for the 4032.
With the proper implemantation it walks all over the OPA627.
Klaus
Some time ago Bechmark Auio as interviewed in TAA about opamps and they disclosed many myths.
Most diyers do not apply opamps correctly particulary with respect to open and closed loop gain.
In another TAA series of articles Paul Stammer discussed many opamps types for audio mixer applications incl some discrete opamps. He concluded nearly all of them performed bette rbiased into class A and also that epower supply was critical for best chip opamp peformance. Stammer regarded the Borbely discrete opamps so superior that he specified them in his article and the 5532 while quiet as poor with a reputation it deserved..
Opamps are just not plug and play and the specs do not necessarily relate to happy listening.
However I would say that the Moamps discrete Opamp published in Moamps crossover is a cut above everything else compared to most typical fet input based chip amps and it uses only a handful of parts.
Comparing a crossover using TL074's and NE 5532 while sounding clean, its sounds sanitized and has an electronic glare which makes the electronics quite audible. On the other hand the simple discrete opamp is far less pronounced but its rendition of musical instruments is quite outstanding.
Moamps is a professional practising audio engineer who's ears I trust!
Most diyers do not apply opamps correctly particulary with respect to open and closed loop gain.
In another TAA series of articles Paul Stammer discussed many opamps types for audio mixer applications incl some discrete opamps. He concluded nearly all of them performed bette rbiased into class A and also that epower supply was critical for best chip opamp peformance. Stammer regarded the Borbely discrete opamps so superior that he specified them in his article and the 5532 while quiet as poor with a reputation it deserved..
Opamps are just not plug and play and the specs do not necessarily relate to happy listening.
However I would say that the Moamps discrete Opamp published in Moamps crossover is a cut above everything else compared to most typical fet input based chip amps and it uses only a handful of parts.
Comparing a crossover using TL074's and NE 5532 while sounding clean, its sounds sanitized and has an electronic glare which makes the electronics quite audible. On the other hand the simple discrete opamp is far less pronounced but its rendition of musical instruments is quite outstanding.
Moamps is a professional practising audio engineer who's ears I trust!
Ths4032
The opamp directly after the (current-output) DAC chip does not have to be unity gain stable. It is converting current into voltage, not configured as a voltage amplifier. But it will oscillate when used as output buffer with 1x gain, but there are ways around that.
Glad to see that finally more people are finding this opamp sounding so good, almost 2 years after I wrote the results of my experiments on the "other' forum; surprised though that it took so long...
Rgds
Marcel
The opamp directly after the (current-output) DAC chip does not have to be unity gain stable. It is converting current into voltage, not configured as a voltage amplifier. But it will oscillate when used as output buffer with 1x gain, but there are ways around that.
Glad to see that finally more people are finding this opamp sounding so good, almost 2 years after I wrote the results of my experiments on the "other' forum; surprised though that it took so long...
Rgds
Marcel
Hello Marcel,
I am really fascinated by the sound of the THS4032 but my knowledge in electronics is not sufficient enough to implement it right in my DVD player. At the moment I have build exactly what you see in pic 1 for the DAC in pic 2 and it sounds already more detailed and clear than anything I had in my room, but I think that it is not ideal. Could you point me in the right direction or make a quick drawing on how to use it as I/V and buffer in my case?
Rgds
Klaus
I am really fascinated by the sound of the THS4032 but my knowledge in electronics is not sufficient enough to implement it right in my DVD player. At the moment I have build exactly what you see in pic 1 for the DAC in pic 2 and it sounds already more detailed and clear than anything I had in my room, but I think that it is not ideal. Could you point me in the right direction or make a quick drawing on how to use it as I/V and buffer in my case?
Rgds
Klaus
Attachments
Hi Radian,
the Vin1 is from ? Could it be the CS4360 is your source?
Why, then load the CS4360 with 50r to ground and 50r to virtual ground resulting in a combined loading of 25r when the datasheet says min load is 3k0?
The output impedance of the CS4360 is 100ohm. You would normally load that with about ten times this impedance say 1k0 but the datasheet over-rules this and says3k0 min.
What you have shown for load impedances is more akin to terminated transmission lines, with high current line drivers feeding them.
With the series resistor shown feeding into the virtual earth I do not think you also need the resistor to ground. Increase the feedback loop resistors to 10k and 3k3 to get your gain of -3.
If you do go with my lowest resistor values you will be limited to a maximum of 10pF stray capacitance. This may be difficult to achieve. Try higher value resistors to get you further of the capacitance scale.
the Vin1 is from ? Could it be the CS4360 is your source?
Why, then load the CS4360 with 50r to ground and 50r to virtual ground resulting in a combined loading of 25r when the datasheet says min load is 3k0?
The output impedance of the CS4360 is 100ohm. You would normally load that with about ten times this impedance say 1k0 but the datasheet over-rules this and says3k0 min.
What you have shown for load impedances is more akin to terminated transmission lines, with high current line drivers feeding them.
With the series resistor shown feeding into the virtual earth I do not think you also need the resistor to ground. Increase the feedback loop resistors to 10k and 3k3 to get your gain of -3.
If you do go with my lowest resistor values you will be limited to a maximum of 10pF stray capacitance. This may be difficult to achieve. Try higher value resistors to get you further of the capacitance scale.
Thanks Andrew for your reply,
Yes CS4360.
I do not have the 100Ohm R1 resistor in place. I just replaced the 3,3 uf coupling cap with Black Gate N and taped the signal at the solder point of the cap, took out the original opamp and left the remainig circuitry in place. The original Rload resistor of the player should still be connected to ground.
Do I understand you right that you would make R6 10k and R4 3,3k?
Is this the only stage you would use or do you think that an additional buffer is beneficial.
Klaus
Yes CS4360.
I do not have the 100Ohm R1 resistor in place. I just replaced the 3,3 uf coupling cap with Black Gate N and taped the signal at the solder point of the cap, took out the original opamp and left the remainig circuitry in place. The original Rload resistor of the player should still be connected to ground.
Do I understand you right that you would make R6 10k and R4 3,3k?
Is this the only stage you would use or do you think that an additional buffer is beneficial.
Klaus
The CS4360 is voltage out, not current out. This means that you do not need an I/V converter, just a voltage follower with maybe a little gain to reach the desired output voltage. You better not use the THS4032 for that because this opamp is not stable at low gain settings. Better use AD797, but be sure to compensate it properly for parasitic capacitances, as suggested in the AD797 datasheet.
-Marcel
-Marcel
Hi Andrew,
I use the circuit as posted except for R1 that I left out since the player has a the 10k Rload resistor at that place.
Marcel,
I am running the THS4032 with the posted circuit for a few days in this player now and I can't hear any ill effects. On the contrary it just absolutely amazes me. It is flat out better than OPA 627. I hear things clearly distinct that I have not heart at all before. The spatial presentation is fantastic.
I think I will not try any other OpAmp in this place.
Klaus
I use the circuit as posted except for R1 that I left out since the player has a the 10k Rload resistor at that place.
Marcel,
I am running the THS4032 with the posted circuit for a few days in this player now and I can't hear any ill effects. On the contrary it just absolutely amazes me. It is flat out better than OPA 627. I hear things clearly distinct that I have not heart at all before. The spatial presentation is fantastic.
I think I will not try any other OpAmp in this place.
Klaus
Hi Klaus,
The THS4032 EVM circuit has 2 big problems:
1. it is inverting phase,
2. it has only 100 Ohms input impedance defined by R4, this loads the outputs of the CS way too much.
It is NOT suitable for voltage output DACs.
Solutions:
1. Use a normal non-inverting voltage amplifier circuit;
2. use higher value feedback resistors, like 22k and 10k for a voltage gain of 3. (in non-inverting opamp schemes the gain factor is 1+ the ratio of the 'series' R from output pin1 to inverting input pin2 and the 'parallel' R from pin 2 to ground).
Put a normal 10k resistor from non-inverting input pin1 to ground to define the ground reference for this input.
3 To increase stability at low gains check datasheets of NUGS opamps (NUGS = not-unity-gain-stable) for proper compensation techniques.
You will have even better sound from your work, because what you are doing now is certainly not OK.
Basic circuitry can be found anywhere on the net and in datasheets, like THS4032 page 24.
Grtz,
Marcel
The THS4032 EVM circuit has 2 big problems:
1. it is inverting phase,
2. it has only 100 Ohms input impedance defined by R4, this loads the outputs of the CS way too much.
It is NOT suitable for voltage output DACs.
Solutions:
1. Use a normal non-inverting voltage amplifier circuit;
2. use higher value feedback resistors, like 22k and 10k for a voltage gain of 3. (in non-inverting opamp schemes the gain factor is 1+ the ratio of the 'series' R from output pin1 to inverting input pin2 and the 'parallel' R from pin 2 to ground).
Put a normal 10k resistor from non-inverting input pin1 to ground to define the ground reference for this input.
3 To increase stability at low gains check datasheets of NUGS opamps (NUGS = not-unity-gain-stable) for proper compensation techniques.
You will have even better sound from your work, because what you are doing now is certainly not OK.
Basic circuitry can be found anywhere on the net and in datasheets, like THS4032 page 24.
Grtz,
Marcel
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