Do you have a link to the thread on diyaudio?
Question about Opamps
- Thread starter Spooter
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Do you have a link to the thread on diyaudio?
Sorry, I don't use typical multi-mixed recordings as a reference.
Evidently, you don't listen to live, unamplified music or are aware of any number of recording labels who have no use for that kind of gear.
ConradH
Lunatic Member
Sorry, I go to see live unamped music all the time, get to hear regular people also playing music in small church settings with real instruments. If you have Chesky, Sheffield and the like labels, they all used some type of mixing, eq'ing, and switching console, whether it was custom built tube gear or otherwise. They might have even used just 2 channels of a multi-channel unit.
The reality is every recording uses some type of "Gear" to get the acoustic sound into a mixing device, and then to the recording medium. The arguments for minimalist techniques and elitist (snobbish?) gear have been around for a long time, and for some in the audiophile world, extends their own biases about what "should" sound good, and everything else "must" sound "less good". But great recordings can be made with many different techniques and gear in between. Choices of mics for example can shade or color an instrument or recording.
If you visit studios that created great recordings, or even onsite recordings at great venues, you'll find plenty of fairly common cables, consoles, and connectors. Very few will have the gilded gold plated connectors (no RCA's for sure, most connectors are XLR's), hundreds of feet of fairly common mic and connecting patch cables and not much DeOxit in sight.
I suppose the only recordings that would suffice would be a two mic setup running into a two channel custom built console straight to the cutter head or analog (tape) recording medium (oh and then we have to account for the recording monitors, amps (SS or tube) and the acoustic space the engineer is listening in, and the hearing and "artistic tastes" of the engineer and artist. Then there's any post production "adjustments").
Obviously, any digitial recording cannot possibly be good because of the complexity of any AD-DA conversion, the hundreds and thousands of transistors in the converters, filters, and clocks, and of course the particular analog buffers and amps (discrete or integrated circuit based) that eventually drive all the output and inputs to the recording medium.
And all this is silicon solid-state based for the most part although there are plenty of tube based products that are used to shape sound. But then the artists must be "altering" the acoustics of what they want you to hear with all that outboard gear, let alone their particular choice of instrument. Frankly, I don't much care for Steinway pianos, Yamaha are decent but tend to be bright in North America, and Bosendorfers are great but fairly unknown in NA.
I guess I just don't like to see or hear someone basically say that the vast majority of people working diligently in the audio recording business don't know what they are doing or how to do it. Audiophiles tend to think of themselves as all knowing at one end of the production spectrum and that gives them carte blanche to criticize or denigrate the work of the artist/engineer/producer team, and the companies that produce equipment to create the recordings.
If a purist effort is the only thing that will suffice, you're entitled to that viewpoint. I personally think there's plenty of great music and recordings recorded on all kinds of gear that happens to sound great despite the lack of "audiophile" qualifications.
mrdbdigital
The TBS Archives
The console we had in production at TBS that I have been talking about was built around 1991 custom for TBS, as a sort of prototype live broadcast console, and that was the first AMS Calrec digitally controlled analog console installed in the US. The mic preamps were of a special BBC design that allowed them to tolerate the live use of starter pistols for special affects on some of the BBC shows. They were extremely clean and low noise, and a LOT of headroom.
We paid $ 334,000 for that console, and all the opamps in the console were NE5532's. The console was a digitally controlled analog console, which consisted of two racks of audio electronics and the control desk. The analog audio never left the racks; there was no audio in the desk except for the monitoring feeds and the VU meter feeds. The desk was connected to the racks via 2 redundant high speed digital serial paths to allow the computer in the desk to control the audio circuitry. All audio switching in the audio path was done with CMOS 4066 family switching chips.
The engineer sent over to install the console was Mark Amory, who was also the chief design engineer for the console. Our installation resulted in several modifications and features that were implemented in later series of their consoles. As this console was the first of it's kind over here, I don't think it had a series or model number.
Thanks for chiming in, Mech986!
Dave
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mrdbdigital
The TBS Archives
You're quite correct. Not all recording engineers are deaf and utterly clueless, and neither were any of the ones I worked with.
Dave
SoundOfSound
Super Member
Recording labels that don't use mixing consoles?
They can record music without going through any electronic amplification?
I'm very curious to hear how this is done, please fill us in on the details.
This sounds very fascinating to me.
I knew that thread, but nothing is said about the considerations using this (AD797) Opamp.
Why not a circuit build around the NE5532?
ConradH
Lunatic Member
Cool tech, invented only recently. You shout into the horn and a small needle vibrates a pattern into the surface of a rotating wax cylinder. Not an opamp in sight and when first heard it was said to be indistinguishable from the live sound!
nashvillebill
Super Member
To the OP's question about circuits expressly for the 5532:
Op-amps like the 5532 are pretty stable, so they work nicely in most any op-amp circuit if general rules for loading, stability, etc. are followed; use the proper voltages, input impedance, etc.
There's a book by Walter Jung, the "IC Opamp Cookbook" that's got plenty of circuits, he's also got "Audio IC op-amp applications". (I don't have copies of these unfortunately but I've seen them). G. Randy Sloane has a couple of books which I do have and they are pretty good: "The Audiophiles Project Sourcebook" covers a lot of circuits.
Online, Rod Elliott has a ton of projects: http://sound.westhost.com/projects.htm He calls for the 5532 in a bunch of them; in some he goes to the OPA2134 (different input impedance, I believe)
Also be sure to read his articles. http://sound.westhost.com/articles.htm
Op-amps like the 5532 are pretty stable, so they work nicely in most any op-amp circuit if general rules for loading, stability, etc. are followed; use the proper voltages, input impedance, etc.
There's a book by Walter Jung, the "IC Opamp Cookbook" that's got plenty of circuits, he's also got "Audio IC op-amp applications". (I don't have copies of these unfortunately but I've seen them). G. Randy Sloane has a couple of books which I do have and they are pretty good: "The Audiophiles Project Sourcebook" covers a lot of circuits.
Online, Rod Elliott has a ton of projects: http://sound.westhost.com/projects.htm He calls for the 5532 in a bunch of them; in some he goes to the OPA2134 (different input impedance, I believe)
Also be sure to read his articles. http://sound.westhost.com/articles.htm
Who said that? Minimally miked recordings don't require massive consoles with "hundreds of op amps".
I use recordings made by labels like Telarc, Windham Hill, Reference Recordings, Mercury, et.al. as a reference of what can be done.
Indeed, most recordings today aren't particularly good or natural sounding.
Of course. Just not necessarily those using "hundreds of op amps". I participated in one Telarc recording long ago and can tell you that Jack Renner didn't use a massive console.
edit: He used a Studer console which used discrete preamplifer and EQ sections. Telarc also used EMM Labs ADCs and DACs which use discrete components.
Sorry, use of the reductio ad absurdum fallacy doesn't work with me. I'll be happy to answer any particular questions you may have.
They do exactly what they are chartered to do - make money. So does McDonalds. So does Chevrolet. I trust that most engineers who produce massively compressed recordings as typically found today really do understand that compromise. The "Loudness Wars" path is taken for economic benefit, certainly not for optimum sound quality!
What spectacular gear and recordings do is shine a bright light on what can be done and serve as a reference. I listen to quite a few crappy recordings because I enjoy the music. As a music lover, hearing wonderful recordings on exceptional equipment, however, transports me to the event.
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ConradH
Lunatic Member
+1 on Walt Jung's op amp cookbook. I still pull that out quite often.
I will say this- I enjoy a lot of Americana and older pop music from the '50s and '60s. Those records have a very different quality than later recordings. Is it because most everything was tubes and less complex signal paths, or possibly standards and styles were just different. We've been exposed to musical "progress" and a listener in the '50s probably couldn't tell it from noise. Like it or not, recent standards (not quite the word I'm groping for) for sound are different and recordings of anything are apt to reflect that. Many of those older recordings are very satisfying in a you-are-there sense, but also have obvious distortion and technical SQ issues like overload and limited s/n ratios.
I will say this- I enjoy a lot of Americana and older pop music from the '50s and '60s. Those records have a very different quality than later recordings. Is it because most everything was tubes and less complex signal paths, or possibly standards and styles were just different. We've been exposed to musical "progress" and a listener in the '50s probably couldn't tell it from noise. Like it or not, recent standards (not quite the word I'm groping for) for sound are different and recordings of anything are apt to reflect that. Many of those older recordings are very satisfying in a you-are-there sense, but also have obvious distortion and technical SQ issues like overload and limited s/n ratios.
dodog
Addicted Member
You'll have to ask HypnoToad why he chose the AD797.
Why not the NE5532? Why not build one yourself and report back. I don't know that anyone has anything against it, it just takes someone to do the legwork.
When I had build one using the NE5532, I still wouldn't have the experience of using the AD797... (and then, yes you're right to ask HypnoToad)
Therefore my first question of this topic still stands:
<<The OP37 is as ancient as the 5532. (Is there really nothing newer?)>>
SoundOfSound
Super Member
Ti is recommending using a OPA2209 as a replacement for the NE5532.
The problem is none of these new hot shot op-amps are made in DIP packages if that's what you need.
Here is what they recommend as replacements in general but be sure to read their disclaimers too. :yes:
http://e2e.ti.com/support/amplifier...tes/upgrading-op-amps-in-audio-equipment.aspx
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big2bird
Well-Known Member
I found this link today. Those so inclined might find it useful:
http://e2e.ti.com/support/amplifier...tes/upgrading-op-amps-in-audio-equipment.aspx
http://e2e.ti.com/support/amplifier...tes/upgrading-op-amps-in-audio-equipment.aspx
Jon_Logan
Addicted Member
Thank you Big2Bird for the link.
It's funny that TI mentions that putting in an AD797 may result in worse performance.
I've found this to be true while modifying a Sound Technology 1701A. I found that the AD797 did not behave well in ST's circuit and resulted in higher noise than the original op-amp. Luckily, swapping op-amps in quiet test THD meters gives you an instant opportunity to see the noise performance of the IC. As far as optimizing the PCB to realize the possible performance improvement of the AD797?????? Fu-getaboutit.
So swap op amps carefully.
It's funny that TI mentions that putting in an AD797 may result in worse performance.
I've found this to be true while modifying a Sound Technology 1701A. I found that the AD797 did not behave well in ST's circuit and resulted in higher noise than the original op-amp. Luckily, swapping op-amps in quiet test THD meters gives you an instant opportunity to see the noise performance of the IC. As far as optimizing the PCB to realize the possible performance improvement of the AD797?????? Fu-getaboutit.
So swap op amps carefully.
Thank you very much for this link. It also gives a clue why the AD797 is not an option for every audio solution.
dodog
Addicted Member
It's not just the AD797. TI states, explicitly:
That statement alone should be a sticky on the DIY forum. Too many people want to "roll" and think you can just swap things willy-nilly. This isn't a comment directed at you, just a comment in general.