Those op-amps may be purchased from Newark for less than $1.00.
Nearly US$1,000 for that player.
The full complement of Cirrus Logic DAC chips would cost about US$40 with shipping, onsie-twosie.
Not so sure it is worth all that.
Peter Wieck
Melrose Park, PA
Not sure which datasheet the OP is using, but the TI NE5532 one claims 5 nV perThanks for your response. I'm looking at Figure 1 page 6 Equivalent Input Noise Voltage vs Frequency https://www.ti.com/lit/ds/symlink/ne5532.pdf?ts=1665523375739&ref_url=https%253A%252F%252Fwww.google.com%252F. Table 7.6 page 5 gives the noise figure @ 30Hz of 8nV/reUHz and a noise figure @ 1kHz of 5nV/reUHz. 30Hz noise is more than a 50% increase over baseline1kHz. The increase in noise looks much worse in Figure 1 - and reading off noise at 30Hz gives a value of about 12 but the y axis labels this as nv - not a typical measure. Surprisingly the 5 nV/reUHz tabulated figure looks beliavable as an average over the audio frequency range in figure 1. converting 5 nV/reUHz to just nV gives a figure of 7 which doesn't really fit at all to figure 1. i think that the y axis of figure 1 is a typo and it should read nV/reUHz but then this would not agree with the tabulated figures unless they've used some averaging for the tabulated. datasheets can be opaque about noise. the popcorn noise yes i'll try and follow that up. clearly noise can meld instruments together and add a noise component giving an impression of an additional instrument. do you think the ear is sensitive to non linear noise?
root Hz at 1 kHz and 8 nV per root Hz at 30 Hz, implying that i/F is not such a
serious problem. Its slew rate is kind of low. Flicker noise, called popcorn noise when I was active, is totally different. Some sources claim that the 5532's bipolar input transistors have high popcorn noise, might be what OP is
hearing.
Not sure which datasheet the OP is using, but the TI NE5532 one claims 5 nV peri'm looking at https://www.ti.com/lit/ds/symlink/ne5532.pdf?ts=1665523375739&ref_url=https%253A%252F%252Fwww.google.com%252F there is a mismatch between figure 1 and the tabulated figure with a possible averaging applied to the tabulated figure. The tabulated figure of 5nV/reUHz figure agrees with figure 1 as an average over the frequency. converting 5nV/reUHz to just nV gives a figure of 7nV and this doesn't really make sense in Figure 1. I think nV - y axis label in figure 1 - is a typo and should read nV/reUHz. yes i'll look into popcorn noise - thankyou for your contribution.
root Hz at 1 kHz and 8 nV per root Hz at 30 Hz, implying that i/F is not such a
serious problem. Its slew rate is kind of low. Flicker noise, called popcorn noise when I was active, is totally different. Some sources claim that the 5532's bipolar input transistors have high popcorn noise, might be what OP is
hearing.
On Wednesday, October 12, 2022 at 3:21:38 PM UTC+1, harris...@gmail.com wrote: >> Not sure which datasheet the OP is using, but the TI NE5532 one claims 5 nV per
root Hz at 1 kHz and 8 nV per root Hz at 30 Hz, implying that i/F is not such a
serious problem. Its slew rate is kind of low. Flicker noise, called popcorn
noise when I was active, is totally different. Some sources claim that the >> 5532's bipolar input transistors have high popcorn noise, might be what OP is
hearing.
i'm looking at https://www.ti.com/lit/ds/symlink/ne5532.pdf?ts=1665523375739&ref_url=https%253A%252F%252Fwww.google.com%252F there is a mismatch between figure 1 and the tabulated figure with a possible averaging applied to the tabulated figure. The tabulated figure of 5nV/?Hz figure agrees with figure 1 as an average over the frequency. converting 5nV/?Hz to just nV gives a figure of 7nV and this doesn't really make sense in Figure 1. I think nV - y axis label in figure 1 - is a typo and should read nV/?Hz. yes i'll look into popcorn noise - thankyou for your contribution.
On Wed, 12 Oct 2022 13:08:46 -0700 (PDT), "oben...@gmail.com" <oben...@gmail.com> wrote:Yes i'm listening to the OPA1662 now. It is impressive thankyou for the design. it combines low noise with a relative high CMRR of 96db in the top octave and a mid value slew. and no rise in 1/f noise though again there looks to be a mismatch between the tabulated (p4) and chart (p6) values. i took the chart values as the correct ones. I'll try and submit a piece on how i used the OPA1662 and with a comparison with other op amps and any use issues. Thanks for your response and a great design thanks.
On Wednesday, October 12, 2022 at 3:21:38 PM UTC+1, harris...@gmail.com wrote:
Not sure which datasheet the OP is using, but the TI NE5532 one claims 5 nV per
root Hz at 1 kHz and 8 nV per root Hz at 30 Hz, implying that i/F is not such a
serious problem. Its slew rate is kind of low. Flicker noise, called popcorn
noise when I was active, is totally different. Some sources claim that the
5532's bipolar input transistors have high popcorn noise, might be what OP is
hearing.
i'm looking at https://www.ti.com/lit/ds/symlink/ne5532.pdf?ts=1665523375739&ref_url=https%253A%252F%252Fwww.google.com%252F there is a mismatch between figure 1 and the tabulated figure with a possible averaging applied to the tabulated figure. The tabulated figure of 5nV/?Hz figure agrees with figure 1 as an average over the frequency. converting 5nV/?Hz to just nV gives a figure of 7nV and this doesn't really make sense in Figure 1. I think nV - y axis label in figure 1 - is a typo and should read nV/?Hz. yes i'll look into popcorn noise - thankyou for your contribution.
Have you considered the OPA1662 https://www.ti.com/lit/ds/symlink/opa1662.pdf?ts=1665661825192&ref_url=https%253A%252F%252Fwww.google.com%252F
I'm partial to it since I designed it, but it may fit your needs.If it doesn't, please tell what parameter disqualified it. .
I looked at the figure and conclude that both axes are mislabeled. Should be nV per root Hz and the frequency axis is off by a factor of 10. Note that the "curve" is just a fitted line to discrete measurements. It looks as though the lowest frequency should be 1 Hz, reflecting the high popcorn noise caused by the input protection diodes. This op-amp is also compensated for unity gain, which always creates trade-offs.thanks for the observations. looks like you're right. more things to think about - thanks
Do you think that there is a link between 1/f noise and pace.
i suppose it depends on how sensitive the ear is to non linear noise. but perhaps
also the importance of bass is in contributing to percieved pace.
On Thursday, October 13, 2022 at 11:23:04 AM UTC-4, oben...@gmail.com wrote:your right. and i cannot fault your argument. i did try and include an independent source (gramophone magazine) of how julia wolfe should sound. but there are sound presentation differences when switch between two CD players. and there are always going to be differences and all factors can not be accounted for and there is no independent measure of things like pace or tone. i suppose if it floats my boat go ahead. thanks for your response and i like your prose style.
Do you think that there is a link between 1/f noise and pace.Since there is no objectively agreed upon definition of "pace", indeed, it mayh well
be one of those normal words co-opted by the high-end high-priests as a completely
vague magic term, the answer is most decidely NO.
i suppose it depends on how sensitive the ear is to non linear noise. but perhapsBut, most importanly, it depends upon who is using the term "pace" to describe
also the importance of bass is in contributing to percieved pace.
what emotional response to which music under what crcumstances after
easting what food at which time of day after having what argument with their spouse and whether they won it or not after a hard day at work and coming home with a headache through rush hour traffic and greeted by their youngest daughter telling them she's pregnant and running off to Morroco with her 57 year old boyfriend. And that's after getting yelled at by your son telling you
he's sick and tired of hearing claim the earth is flat.
your right. and i cannot fault your argument. i did try and include an independent source (gramophone magazine) of how julia wolfe should sound. but there are sound presentation differences when switch between two CD players. and there are always going to be differences and all factors can not be accounted for and there is no independent measure of things like pace or tone. i suppose if it floats my boat go ahead. thanks for your response and i like your prose style.There is grave danger in accepting a third-party definition of how things 'should' sound. As that third party, typically, does not have access to your ears, listening area, equipment and specific preferences. ANd accepting 'received wisdom' in very nearly every case will lead you down the proverbial garden path, with potential quicksand a the end.
thanks for this, the point is there are differences between op amps. if enough people make a comment about an op amp it must come from some common experience. we can not listen to every op amp and cd combiation playing every type of music. and op amp metrics offer some way to understanding how an op amp sounds or performs. i believe 1/f noise is one such metric. in the past i used to think slew gave an indication of pace. i now no longer accept this. 1/f noise and how we interpret non-linear noise seems a possible hypothesis for understanding pace.your right. and i cannot fault your argument. i did try and include an independent source (gramophone magazine) of how julia wolfe should sound. but there are sound presentation differences when switch between two CD players. and there are always going to be differences and all factors can not be accounted for and there is no independent measure of things like pace or tone. i suppose if it floats my boat go ahead. thanks for your response and i like your prose style.There is grave danger in accepting a third-party definition of how things 'should' sound. As that third party, typically, does not have access to your ears, listening area, equipment and specific preferences. ANd accepting 'received wisdom' in very nearly every case will lead you down the proverbial garden path, with potential quicksand a the end.
As you state, it floats your boat, and as your choice of options to investigate, entirely valid - for you!
Enjoy!
Peter Wieck
Melrose Park, PA
thanks for this, the point is there are differences between op amps.
if enough people make a comment about an op amp it must come from some common experience.
we can not listen to every op amp and cd combiation playing every type of music. and op amp
metrics offer some way to understanding how an op amp sounds or performs.
i believe 1/f noise is one such metric.
1/f noise and how we interpret non-linear noise seems a possible hypothesis for understanding pace.
Within the realm of capacitors, again after that basic quality control is met, and the appropriate materials are specified, a cap is a cap is a cap is a cap.
I tend to agree. In the realm of serious high-end audio, a fraction of a percent difference can sometimes be heard. When I was rebuilding stuff for my own amusement in college...Within the realm of capacitors, again after that basic quality control is met, and the appropriate materials are specified, a cap is a cap is a cap is a cap.
I have to respectfully disagree. Capacitor dielectric materials have widely varying characteristics. One phenomenon which I struggled with in design of space electronics is dielectric absorption coefficient. This can range from thousandths of a percent to several percent. How it impacts a circuit is a function of design. The dielectric coefficient can also vary with applied voltage. Application and design are important. I would not state that a capacitor was better without examining its circuit diagram and consider its operating biases. In some cases, frightfully expensive ones, such as Teflon foil, are the only acceptable solution.
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