I think that the input cap was left in the Parasound phono preamp, because the engineer was too lazy to change the circuit. It was probably originally designed for the 5532 or something worse. I chose the AD712, because it was fet input (I like fet input) and is faster (slew rate) than a 5532.
Well I am looking at the documentary right now and it is damn interesting and provocative to the capitalist world .
😀 😀 😀
Before I start counting, does anybody know how many 5532 there are from the input of the console to the output of the mastering? A wild guess: 20? Prof. T.? And yet we can still hear a difference swapping little things downstream!
It's sad but there's no perfect op amp for anything in the end, everything is just good enough for the job.
I am 42, i didn't live during the times where you couldn't find good capacitors or matched complementary bipolars easily, but i live the times where you can't find complementary matched original low noise fets at all or at a reasonable price.
Which is actually good because it makes me and others think of how to deal with it, finding new ways.
For a DIY'er, you can still find them at about $50 for 2 pairs, with which you can hope to compete with multi-k-$ hi end products. Good deal still. I wouldn't even think of starting a production run though.
!!!!!!!!!!!! YES !!!!!!!!!!!!!!!!
THAT IS THE WAY AUDIO WORKS !
10 I.C's ( or whatever ) in series preceding a 11th
WILL NOT mask the artifacts of the 11th !
A VERY important ( though little known ( let alone understood ) )
truth !
I did find an analysis of a Neve that had about 54 for a channel. I'll try and dig it out if I get some time.
I assume everyone has seen the Dave Grohl orgasm film about his mixing desk?
I'd buy them at this price plus one more pair as reserve if i'd have to fix a 1 k amplifier with these parts, maybe a little bit less ... I wouldn't buy them to fix a 500 dollars amp because the owner wouldn't pay me more than 50 dollars to do it in my country and then he might need a guarantee too for his amp in this money, plus i need to pay my taxes ...but then if for some reason he burns them again i'd be needing to replace them for free as guarantee.
You need a real solid source of components if you want to fix high end stuff on a regular basis.He'd maybe spend 100 dollars to fix a 500 dollars amp,
but building new amplifiers out of ebay sourced components and hoping today that you're going to sell it for thousands...🙂))))))
By the way...I have two pairs sourced from marantz cd 67.
Should i sell'm or build one channel of an amp and hope i'll find another broken player for the second amp?
When I'll be finished i'll advertise here for that million bucks waiting to make me rich.
Should i sell'm or build one channel of an amp and hope i'll find another broken player for the second amp?
When I'll be finished i'll advertise here for that million bucks waiting to make me rich.
A typical mixing console will have either a microphone level input transformer or a low noise bipolar input stage. This is followed by the first variable gain stage.
This is followed by an insert point that may be buffered but usually is not.
Then comes the bypass able tone control stage. This will be several parametric filters that may use up to four gain stages often individually bypassable. These sections will be summed by a unity gain stage.
This will feed a number of sends for monitoring or effects, the main signal will go to a fader that is possibly buffered.
The output of the fader is switched to different busses such a a left, right, mono etc. These busses use another summing amplifier. Then perhaps a line driver.
Now how do opamps contribute? It is all in the first gain stage!! Virtually every stage after that runs at unity gain.
So it is reasonable to have the signal flow through one gain stage and then four to six unity gain stages. So the signature sound almost all of it comes from the microphone input gain section. Probably the reason there are so many outboard microphone preamps.
Yes there are hundreds of opamps in a console but effectively all in parallel. So even the noise only sums by the root sum not algebraicly.
This is followed by an insert point that may be buffered but usually is not.
Then comes the bypass able tone control stage. This will be several parametric filters that may use up to four gain stages often individually bypassable. These sections will be summed by a unity gain stage.
This will feed a number of sends for monitoring or effects, the main signal will go to a fader that is possibly buffered.
The output of the fader is switched to different busses such a a left, right, mono etc. These busses use another summing amplifier. Then perhaps a line driver.
Now how do opamps contribute? It is all in the first gain stage!! Virtually every stage after that runs at unity gain.
So it is reasonable to have the signal flow through one gain stage and then four to six unity gain stages. So the signature sound almost all of it comes from the microphone input gain section. Probably the reason there are so many outboard microphone preamps.
Yes there are hundreds of opamps in a console but effectively all in parallel. So even the noise only sums by the root sum not algebraicly.
No, this is an older design. What I have in mind is a complementary "pair" at the input, driving a voltage gain stage, and an output buffer, but I don't have any complete schematic on hand.
Right...we don't even know of what we are talking about...I'm out of this topic until i'll be shown the schematic of that blowtorch preamp or amp ot whatever it may be...
May-be not 20, for the desks that used them, because slides are //, but for sure they were many in many mixing desk. Many TL07X as well, when no low load was a requisite, because 5532 were quite expensive at this time.
"And, yes we can still hear a difference swapping little things downstream!"
Not surprising: sound engineers "sculp" the sound of each instruments according to what they hear at the output of the desk.
Oh, I didn't read the answer of Simon sayin the same thing, (but forgetting in his count the one after the fader right before the buses ?
Apart the tone controls, they are most of the time unity gain, right.
But not the buses inputs, that increase its gain each time a slide is plugged in it. The first ones to change when you want to improve the sound of a mixing desk
Most of the IC based desk i know used discrete devises for mic préamp.
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Patented: Cable elevator that neutralizes static electric interference
A two page advertisement by Shunyata Research, printed in The Absolute Sound, included the patent number. It's quite a hoot:
https://patentimages.storage.googleapis.com/fa/71/62/b1cad5cfefeab9/US7694917.pdf
A two page advertisement by Shunyata Research, printed in The Absolute Sound, included the patent number. It's quite a hoot:
https://patentimages.storage.googleapis.com/fa/71/62/b1cad5cfefeab9/US7694917.pdf
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