"What is wrong with op-amps?"
for starter, you can't make power supply for each stage separately.
just trying to be constructive here . . . 😀
for starter, you can't make power supply for each stage separately.
just trying to be constructive here . . . 😀
Derf is this you?
"...what need have I for this, what need have I for that, all is bliss, all is bliss, I am dancing at the feet of my Lord..." - Ravi Shankar/John McLaughlin in Shakti
_-_-
"...what need have I for this, what need have I for that, all is bliss, all is bliss, I am dancing at the feet of my Lord..." - Ravi Shankar/John McLaughlin in Shakti
_-_-
Yes, perhaps, but no.
Otoh, perhaps you and others could not post anything unless there is something to say that furthers the dialog in a constructive manner?
Who knows, that might work too...
Frankly I read a whole lot of "bang my drum, bang my drum, I am right, I am right..." and a whole lot of repetition of the same tired rhetoric.
The guy posts something about separate power supplies for each stage.
Not to be taken seriously?
Why not?
Everything is "good enough" now?
Interestingly, and by way of anecdote, someone I know did just this with a tube RIAA/preamp design (many years ago) and nobody liked the sound compared to the SAME circuit with a different (does it matter what?) power supply configuration.
Move on folks, nothing to see... move along...
It's all settled, shut down the thread...
Then this came along like a knife in my chest,
"As usual, my search for the perfect (and affordable) phono pre continues. I like my instrument detail of the Cambridge, but the Lounge paints a more realistic picture of a symphony orchestra---😱just from several more rows back than I prefer to sit.😱 The Lounge does everything well, and some things very well. It may be a very good fit in a system that is already highly detailed."
The above was written in Oct of 2011 on Audiocircle BTW.
well this whole 'closer/further back' part is well known about and often due to a midrange dip in FR, usually referred to as the 'presence dip'. There may also be HF roll off at play. If you look here Records and Reality and scroll down a bit there is the standard graph of air absorption. A dB here or there could make it seem like you are further back in the hall. Now of course whether the listener perceives this as being further back , or the sound stage moving back depends on a number of things, not least how he has calibrated his perception. Most of us don't get to move seats during a concert after all to know what 3 rows further back sounds like!
You don't mention the cartridge he is using, but it's entirely plausible that one of the Phono stages he was using gave audible FR differences and he preferred one to the other. Which one we will never know!
I don't get it. Something like the LM4562 has phenomenal audio specifications.
Nothing like the trusty 741, which was designed for something different than quality audio.
Slew 20V uS
GBW 55MHz (!)
THD (nothing!)
Noise (nothing!)
CMRR 120dB.
Output typical 42mA (plenty).
I appreciate proper supply and PCB design, input and output loading etc. But if you can't use one of these and get into the top 1% of audio quality: then you're not doing it right.
Surmounting the final 1%? Very subjective!
If I'd have been shown an OP amp with a spec like that at college, it would have come from Area 51 🙂
Nothing like the trusty 741, which was designed for something different than quality audio.
Slew 20V uS
GBW 55MHz (!)
THD (nothing!)
Noise (nothing!)
CMRR 120dB.
Output typical 42mA (plenty).
I appreciate proper supply and PCB design, input and output loading etc. But if you can't use one of these and get into the top 1% of audio quality: then you're not doing it right.
Surmounting the final 1%? Very subjective!
If I'd have been shown an OP amp with a spec like that at college, it would have come from Area 51 🙂
Given that most component manufacturers will supply detailed parasitic models (or you can measure) that will be good up to GHz then you can certainly calculate the changes. In general sod all at audio frequencies of course except for the usual suspects.
But I understand that you are in the game of selling the dream. Your products are sensibly priced and the target market will gain the marvellous placebo of knowing their unit was painstakingly voiced over a period of months. win/win there. Of course most on here are not your target market, but you already knew that 🙂
I got that. More soul in my Charity shop enclosures than I know what to do with. 45 years of experience in those old cabs. The Soundpad (70s) 2*12 guitar cab re-purposed to 1*12 sub has years of experience.
Trucker mid/highs? Who knows. 70s speakers with 2016 drivers.
If my 90 year old violin had something to say? I don't know, it would be amazed with the sound quality you can get for peanuts now 😀
Trucker mid/highs? Who knows. 70s speakers with 2016 drivers.
If my 90 year old violin had something to say? I don't know, it would be amazed with the sound quality you can get for peanuts now 😀
Sure you can go to any electronics big box store and get stuff that is likely better than the solid state stuff from the 70s up to today. But does it sound or is it more pleasant to listen to than go tube stuff from the 60s? (especially if the old tube gear has had it's basics upgraded, resistors, caps and PS??)
And since all this opamp based stuff for the past 10-15 years uses "ultra low distortion" opamps (at least the ones that do) obviously it's all of pretty much equal quality "under the hood" and so there's NOTHING MORE TO DO OR SAY. (unless ur buying boxes and "features")
Go home, get a new hobby... model trains, coins, cars, boats, stamps, woodworking, go mow your lawn (if you have one)... or <gasp> politics (another fine pastime)!
And since all this opamp based stuff for the past 10-15 years uses "ultra low distortion" opamps (at least the ones that do) obviously it's all of pretty much equal quality "under the hood" and so there's NOTHING MORE TO DO OR SAY. (unless ur buying boxes and "features")
Go home, get a new hobby... model trains, coins, cars, boats, stamps, woodworking, go mow your lawn (if you have one)... or <gasp> politics (another fine pastime)!
My design methods never fail to bring out the very well stocked inventory of curmudgeon, by the book EE's the world has.
Design methods far less than insulting those same, soulless, automaton, by-the-book EE's that y'know, make things work? Or developed most of the base components you use?
Eschewing rigor is the joyous position of being in a field where ad copy and abject subjectivism is more important than actual performance.
Eschewing rigor is the joyous position of being in a field where ad copy and abject subjectivism is more important than actual performance.
I do really recommend going through some of the audibility tests a few generous members (Mooly and BWaslo come first to mind) have made available. We can argue this or that as far as the musical selections, but they do ballpark one's ability.
Or Bob Carver's challenge, which I think was nulled to -60 dB? I might be mis-remembering this, but the overall impression was that audibility of effects below -60 dB the primary signal are going to be VERY TOUGH moving towards impossible. If my background here is wrong, someone please correct me. And single tone sensitivity will assuredly be better than with complex signals (aka music), but I don't know about y'all, I like music much better than listening to a single tone.
So, even if we accommodate that we'd want measurements to be able to clearly differentiate at a factor of 10 better than -60 dB, we're talking measuring differences in the -80 dB range. Well within the range of many a good sound card, much less higher-end tools and jigs.
Ergo, I don't think your analogies to listening to a metal detector vs the readout quite hit the mark.
It's that 1% that's subjective. I'm happy with 99% today. A good (superb?) benchmark.
There is nothing wrong with op amps and my perception of the state of the art is that its on the top of a logarithmic curve, but still improving.
99% in another 20 years will be something different again. I'll look back and laugh with you at the old silicon technology when we get there. Personal taste will still be what you want it to be. That's human.
When the argument comes down to stone tools vs bronze and then bronze vs iron, then it becomes very personal and (carefully), more subjective and perhaps less relevant 😱
We agree though. Nothing is perfect. The closer you get, the more difficult it becomes to see what isn't perfect. We're not making musical instruments, art or fashion here. We shouldn't be.
There is nothing wrong with op amps and my perception of the state of the art is that its on the top of a logarithmic curve, but still improving.
99% in another 20 years will be something different again. I'll look back and laugh with you at the old silicon technology when we get there. Personal taste will still be what you want it to be. That's human.
When the argument comes down to stone tools vs bronze and then bronze vs iron, then it becomes very personal and (carefully), more subjective and perhaps less relevant 😱
We agree though. Nothing is perfect. The closer you get, the more difficult it becomes to see what isn't perfect. We're not making musical instruments, art or fashion here. We shouldn't be.
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Very nice work here, the fact that the Halcro guy does metal detectors is a little ironic in this context. Way beyond beeps.
https://www.minelab.com/__files/f/11043/KBA_METAL_DETECTOR_BASICS_&_THEORY.pdf
It was an accidental pun when I first drafted the response.
😀
I agree with much of what you write, with a few nits, perhaps. But I'm a pain, so of course I'm going to have nits! 😀
First off, -60 dB is 0.1% 😉
The trick here is we as humans aren't getting new ears, so the end listening tool (our ears/brain with all the attendant value added here) aren't getting any better. Or at least not terribly quickly (dunno if there's much biological selection for exceptional hearing 😀). That's before accounting for hearing loss factors.
Playback, especially, especially in the scope of line-level electronics, has readily past a level where one can design a system that greatly exceeds even the most optimistic ability to hear. And that's getting easier and easier to do with modern opamps. Even most of the popular 80's opamps could do the job. So, sure, future IC's will continue to push some matrix of noise, linearity, and power consumption (probably the biggest driving force now) to new levels, but its audible advantage is heaping margins on margins.
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