Quite interesting... That big "measurement shootout" by Samuel Groner had suggested the LT1213/1215 as interesting opamps, like the rail-to-rail output LT1632 (and also the slower LT1630), besides the already well-known LT1469. Judging by his measurements, the LT1469 should be the best of the bunch overall... I don't know. I definitely liked its transparency etc., but I have no more (and they have stopped sending me samples 
).
It's a real pity that the guy chose to test the LT1115 (also very interesting sounding - but doesn't come as SO8), not the more transparent (and more expensive) LT1028.
).It's a real pity that the guy chose to test the LT1115 (also very interesting sounding - but doesn't come as SO8), not the more transparent (and more expensive) LT1028.
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hehe, LT banned you from the samples program 
well, I've got a new toy and the 2*Earth are driving my headphones...I don't really feel like rolling anymore: ImageBam - Fast, Free Image Hosting and Photo Sharing
the LT1213 has a clear/natural/accurate sound, and Earth embelishes it beautifully
some asian guy(found through google) said LT1213 had a clear and HD sound...I fully agree, it's definitely a LM4562/49720 killer, it does it all the same...just miles better, like only LT knows
maybe I'd try the LT1469 again, but I found its trebles metallic to death in the past...and I'm bored of rolling
well, I've got a new toy and the 2*Earth are driving my headphones...I don't really feel like rolling anymore: ImageBam - Fast, Free Image Hosting and Photo Sharing
the LT1213 has a clear/natural/accurate sound, and Earth embelishes it beautifully
some asian guy(found through google) said LT1213 had a clear and HD sound...I fully agree, it's definitely a LM4562/49720 killer, it does it all the same...just miles better, like only LT knows
maybe I'd try the LT1469 again, but I found its trebles metallic to death in the past...and I'm bored of rolling
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Universal Soldier: ASUS Xonar D2 PM Sound Card Review (page 4) - X-bit labs
even BB in the PCM1792A datasheet recommends LT1028 for I/V, these chips really must have something special to them indeed ^^
even BB in the PCM1792A datasheet recommends LT1028 for I/V, these chips really must have something special to them indeed ^^
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Perhaps your card doesn't have adequate power supply bypassing for such a fast opamp (90 MHz GBW). You could try adding some .1 uF (100 nF) ceramic bypass caps on the back of the sockets, across pins 4 and 8.maybe I'd try the LT1469 again, but I found its trebles metallic to death in the past...and I'm bored of rolling
I didn't mind it but it does lack some color, similar to the OPA627 (and, less severely, the OPA827).
Obviously I don't consider what sounds like that to be neutral - much the same as too little bass or too little treble would depart from neutrality. It's something lacking that should've been part of the picture.
Obviously I don't consider what sounds like that to be neutral - much the same as too little bass or too little treble would depart from neutrality. It's something lacking that should've been part of the picture.
No, sonic color (or lack of it) has nothing to do with compensation. Besides, I put them in different places... and the result didn't change.
Actually in a modified DVD player the OPA2107 was nice... bit "electric" sounding perhaps, but there I liked it as much as an LME49860 if not better.
How can you say that... it might be on the edge of instability... that would certainly give it a bit of a "sonic signature or colour"
Not really...by color I mean color, precisely... like the colors of the rainbow
I know that some people don't perceive colors in sound as I do but... I do...
Anyway, speaking of my DAC where I've been putting the opamps lately, I've never found any opamp to be on the edge of instability. Either they seemed like they were perfectly stable (not running warm or misbehaving sonically), or they just completely distorted, as in 90% of harmonic distortion
(only a few: EL2228, OPA2822, THS4031). Even AD826 and LM6172 (not among the best sonically.....) worked absolutely fine.
Undercompensated = screechy mids or shouty. Put this op amp in inverting mode to stop the shout.
Overcompensated = dull. Put this op amp in non-inverting mode to perk it up.
Your circuit has only one of these options. There are also specific resistor options for circuit and these are required to operate optimally. Without it, there would be much variety, most of which is caused by the error of application mismatch. This error is like the substitute of a screwdriver with a hammer, which can be terrible if it was done on accident; likewise, very entertaining if done on purpose.
I'm sorry for this news and I thank you for helping me learn more about the topic.
P.S. TDA2030 versus TDA2030A give an example of a difference in compensation (the documentation is fantastic--almost readable!). Your unity-stable selection might sound dull if run in inverting mode, and likewise, your non-unity-stable selection might shout in non-inverting mode. That's only half the "big picture" or less, but it might help a bit.
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I believe that those are extremes that aren't reached in reality with the common opamps and in my DAC's circuit. I might be wrong...
Interestingly with the same opamp (LME49720/LME49710) my 2 DACs sounded identical, despite the differences in opamp supply voltage and in the circuit topology around the opamp. So I guess that the crucial factor is what the opamp is, not how 'optimised' it is, in my real-world case. Of course those few opamps that didn't work at all are excluded from my reasoning..
Interestingly with the same opamp (LME49720/LME49710) my 2 DACs sounded identical, despite the differences in opamp supply voltage and in the circuit topology around the opamp. So I guess that the crucial factor is what the opamp is, not how 'optimised' it is, in my real-world case. Of course those few opamps that didn't work at all are excluded from my reasoning..
The opamps that didn't work: What do they all have in common?
The opamps that are nicest: What do they all have in common?
The answer to both questions might point the way a bit.
The next question is: What are the resistor values that operate the opamp within your circuit? Typically, there's two as partners in a voltage divider (fixed volume control) at the feedback, and there's two more doing that same job at the input. Thats four resistors per Each channel (although there may be more). You can check them with an ohmmeter and the readout will tell you what they are.
The ohmmeter will also tell you what pin of the opamp is connected to which resistor because that will read 0 (solid wire figure) on the end of a resistor that's directly connected to the opamp.
Then you can make a sketch and post it.
I have it ready for use... here's the output summer/filter/buffer of my DAC, drawn by someone else (well, it is not the latest revision of the DAC like I have myself, but the values might have remained the same)...
Oh, BTW, I've replaced that 47uF low quality output cap with 4.7uF Wima's.
And I was forgetting to mention that the stock opamp was an LT1364.
Oh, BTW, I've replaced that 47uF low quality output cap with 4.7uF Wima's.
And I was forgetting to mention that the stock opamp was an LT1364.
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They're all designed explicitly for audio?? Otherwise seemingly very little (e.g. OPA132UA and LT1028)
I suspect it's the high GBW, and/or the high input bias current (might interfere with the muting circuitry which seems to be sorted out in a slightly peculiar way).
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ahhhh, I'm in love (again )
LT1124ACN8 sounds really fantastic! better than 1213, SS is amazing, distortion is inaudible, bass is good, vocals are upfront, stereo localization is spot-on...it's like an undistorted LT1364CN8. I think we got a winner
Linear Technology - LT1124 - Dual/Quad Low Noise, High Speed Precision Op Amps
EDIT: probably.. http://focus.ti.com/lit/an/slyt174/slyt174.pdf
)LT1124ACN8 sounds really fantastic! better than 1213, SS is amazing, distortion is inaudible, bass is good, vocals are upfront, stereo localization is spot-on...it's like an undistorted LT1364CN8. I think we got a winner
Linear Technology - LT1124 - Dual/Quad Low Noise, High Speed Precision Op Amps
is that something I want
EDIT: probably.. http://focus.ti.com/lit/an/slyt174/slyt174.pdf
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