R
RAMI
Guest
Oh yeah? well, i think more than u know......
Oh yeah? well, i think more than u know......
Steenamaroo
...
LOL. Welcome back. 
R
RAMI
Guest
miroslav
Cosmic Cowboy
An understudy perhaps...?
ashcat_lt
Well-known member
Impedance matters exactly because
there's a voltage divider created by the connection. In this image, your source's out-Z would be R1, and the load's in-Z is R2. I think it requires only a grade school level understanding of math to see that Vout goes down as R1 gets bigger with respect to R2, and that if we want as much voltage out as possible then R2 should be a whole lot bigger than R1. If R2 is ten times R1 then the output voltage will be 10/11 of the input, which is less than 1db down, which we consider to be negligible, and thus the 10:1 rule of thumb.
But this is for purely resistive components. If either the output or the input include reactive (inductive or capacitive) components, then which ever "R" they represent above will actually be frequency dependent. Most active devices can be considered to be purely resistive because any reactive part of their impedance contributes very little in comparison. We can't go too wild with this, though, as there usually is some largish capacitance in series (AC coupling capacitors) with R1, which gets bigger for lower frequencies, so that if R2 gets really small, we can lose bass response.
The cables we use to connect our equipment are capacitive, and in parallel with R2 such that R2 gets smaller for higher frequencies. Therefore, if R1 is very large we can lose some treble.
A passive guitar pickup has a pretty large resistive component but is also very inductive. Therefore, R1 starts kind of big and then gets a whole lot bigger at higher frequencies. Therefore, if R2 is smallish, we lose a lot of treble. Of course, in most passive guitars, R2 is actually more like the parallel total of the values of the pots in the guitar, so the math gets a little tougher, but basically we want the input-Z to be as big as possible so that the Vs and Ts on the guitar itself are the main factors in the overall tone. As for this assertion that most people can't tell the difference between plugging into a 1M vs 56K, well...most people are dinks. For most passive guitars, there will be a pronounced difference in the top end. I can't imagine anybody would argue they don't hear a difference when they turn their T knob down to 6...I suppose, not everybody really wants all of the treble possible out of their guitars, but there is a big difference.
I still think there's something fishy with the specs as stated. Honestly, I think that this is probably rebranded cheap crap from somewhere in the orient, that the brand owners don't actually have a clue what it is, or how it works, or what any of these specs mean.
The fact that it is cheap doesn't really have to mean that it is particularly inferior in audio quality. It is extremely cheap and easy to make a damn good line mixer of this sort. It's really just some resistors - which are practically free - and a dual opamp - of which the really good enough ones are also pretty damn cheap. It doesn't take any fancy engineering to "develop" the circuit. It's right there on the datasheet for the opamp, a circuit that's been tried and tested and used in damn near everything for decades now. The "hard" part is the power supply, and even that's not that hard. Again, the methods to do it right are old and well known and those components don't cost that much either. So, the electronics part of this is less than $5 for you or me buying in singles, and for a factory in China buying millions at a time...
The real expense comes in the jacks especially, and maybe the pots next. I wouldn't expect even the cheapest to really degrade the audio performance all that much at first. The cheaper parts are more likely just shoddy, and more likely to fail sooner, and that's where you're going to see the big problem with this cheap thing. The company is likely not spending much on QA, so the thing might just show up broken to begin with, and I would worry about long term reliability. How long will it take for those cheap jacks to go intermittent, or the pots to get scratchy?
What are the legitimate uses for such a thing? Since this is 2014, and this is homerecording.com, I'd say the most common use would be for "analog summing". It's exactly what those fancy (expensive) boutique summing mixers do. Run 4 stereo stems out of your DAW, plug all the Ls into the Ls and all the Rs into the Rs and plug the outputs into whatever you're mixing to - usually a couple of inputs on your interface. In the 90s things like this were often marketed to keyboardjists/synthesists. We would connect the stereo outputs from our various MIDI sound modules into this simple little thing and control EQ and usually even level from the individual boxes themselves. You really can use it to connect whatever to whatever, as long as you watch things a little bit. I might not plug any passive guitars directly into the thing, but the output of about any guitar pedal should be fine. Most "line level" sources should also be fine. Most microphones will be fine.
Gain staging is always a concern, of course, but sometimes we have to do what we can do. An SM57 is not a particularly sensitive microphone, so sure maybe it "needs" 60db gain to get up to line level. We would very much prefer to get that gain as soon as possible so that we're only amplifying the first stage or two worth of noise. But sometimes you can get away with getting the gain a little further down the line. If you must, you must. If you're recording to cassette, you'll probably never notice the difference. Recording to digital...well maybe it'll just sound like you recorded to cassette...
When somebody comes along and asks a question like in the OP, I make the assumption that they want to actually learn something about the underlying concepts so that they can make better informed decisions about their purchases. I feel that is pretty important, actually, whether the budget is $15 or $15,000. I can understand explaining the real science behind why this or that might work better or be less than ideal, but just saying "No, that's the wrong way to do it" doesn't really answer the question.
I'm not completely convinced that it's going to be the worst thing that anybody has ever done to try to record something important to them. It has potential to be kinda decent. The device itself can be used for any number of different applications with acceptable results. It is, to an extent, expandable. Save up some dough and buy something like a Nady PRA-8 for $99, plug it into this thing, and you've got something on par with the Mackie 8 channel mixers for $115. No eqs, but more flexible in some ways...
there's a voltage divider created by the connection. In this image, your source's out-Z would be R1, and the load's in-Z is R2. I think it requires only a grade school level understanding of math to see that Vout goes down as R1 gets bigger with respect to R2, and that if we want as much voltage out as possible then R2 should be a whole lot bigger than R1. If R2 is ten times R1 then the output voltage will be 10/11 of the input, which is less than 1db down, which we consider to be negligible, and thus the 10:1 rule of thumb.
But this is for purely resistive components. If either the output or the input include reactive (inductive or capacitive) components, then which ever "R" they represent above will actually be frequency dependent. Most active devices can be considered to be purely resistive because any reactive part of their impedance contributes very little in comparison. We can't go too wild with this, though, as there usually is some largish capacitance in series (AC coupling capacitors) with R1, which gets bigger for lower frequencies, so that if R2 gets really small, we can lose bass response.
The cables we use to connect our equipment are capacitive, and in parallel with R2 such that R2 gets smaller for higher frequencies. Therefore, if R1 is very large we can lose some treble.
A passive guitar pickup has a pretty large resistive component but is also very inductive. Therefore, R1 starts kind of big and then gets a whole lot bigger at higher frequencies. Therefore, if R2 is smallish, we lose a lot of treble. Of course, in most passive guitars, R2 is actually more like the parallel total of the values of the pots in the guitar, so the math gets a little tougher, but basically we want the input-Z to be as big as possible so that the Vs and Ts on the guitar itself are the main factors in the overall tone. As for this assertion that most people can't tell the difference between plugging into a 1M vs 56K, well...most people are dinks. For most passive guitars, there will be a pronounced difference in the top end. I can't imagine anybody would argue they don't hear a difference when they turn their T knob down to 6...I suppose, not everybody really wants all of the treble possible out of their guitars, but there is a big difference.
I still think there's something fishy with the specs as stated. Honestly, I think that this is probably rebranded cheap crap from somewhere in the orient, that the brand owners don't actually have a clue what it is, or how it works, or what any of these specs mean.
The fact that it is cheap doesn't really have to mean that it is particularly inferior in audio quality. It is extremely cheap and easy to make a damn good line mixer of this sort. It's really just some resistors - which are practically free - and a dual opamp - of which the really good enough ones are also pretty damn cheap. It doesn't take any fancy engineering to "develop" the circuit. It's right there on the datasheet for the opamp, a circuit that's been tried and tested and used in damn near everything for decades now. The "hard" part is the power supply, and even that's not that hard. Again, the methods to do it right are old and well known and those components don't cost that much either. So, the electronics part of this is less than $5 for you or me buying in singles, and for a factory in China buying millions at a time...
The real expense comes in the jacks especially, and maybe the pots next. I wouldn't expect even the cheapest to really degrade the audio performance all that much at first. The cheaper parts are more likely just shoddy, and more likely to fail sooner, and that's where you're going to see the big problem with this cheap thing. The company is likely not spending much on QA, so the thing might just show up broken to begin with, and I would worry about long term reliability. How long will it take for those cheap jacks to go intermittent, or the pots to get scratchy?
What are the legitimate uses for such a thing? Since this is 2014, and this is homerecording.com, I'd say the most common use would be for "analog summing". It's exactly what those fancy (expensive) boutique summing mixers do. Run 4 stereo stems out of your DAW, plug all the Ls into the Ls and all the Rs into the Rs and plug the outputs into whatever you're mixing to - usually a couple of inputs on your interface. In the 90s things like this were often marketed to keyboardjists/synthesists. We would connect the stereo outputs from our various MIDI sound modules into this simple little thing and control EQ and usually even level from the individual boxes themselves. You really can use it to connect whatever to whatever, as long as you watch things a little bit. I might not plug any passive guitars directly into the thing, but the output of about any guitar pedal should be fine. Most "line level" sources should also be fine. Most microphones will be fine.
Gain staging is always a concern, of course, but sometimes we have to do what we can do. An SM57 is not a particularly sensitive microphone, so sure maybe it "needs" 60db gain to get up to line level. We would very much prefer to get that gain as soon as possible so that we're only amplifying the first stage or two worth of noise. But sometimes you can get away with getting the gain a little further down the line. If you must, you must. If you're recording to cassette, you'll probably never notice the difference. Recording to digital...well maybe it'll just sound like you recorded to cassette...
When somebody comes along and asks a question like in the OP, I make the assumption that they want to actually learn something about the underlying concepts so that they can make better informed decisions about their purchases. I feel that is pretty important, actually, whether the budget is $15 or $15,000. I can understand explaining the real science behind why this or that might work better or be less than ideal, but just saying "No, that's the wrong way to do it" doesn't really answer the question.
I'm not completely convinced that it's going to be the worst thing that anybody has ever done to try to record something important to them. It has potential to be kinda decent. The device itself can be used for any number of different applications with acceptable results. It is, to an extent, expandable. Save up some dough and buy something like a Nady PRA-8 for $99, plug it into this thing, and you've got something on par with the Mackie 8 channel mixers for $115. No eqs, but more flexible in some ways...
R
RAMI
Guest
R
richardosim78
New member
i cant know everything... but if u would think more u wouldnt talk nonsense..
R
RAMI
Guest
Ironic statement of the month.
Anders Erisian
XLIII
Hey, i wasn't saying that impedance matching is irrelevant - pretty much the opposite. I reckon knowing the intimate technical details of how things you use work is extremely valuable, be it a car, chainsaw, mixer or a blunt stick, and allows you to get the best out of what you are using. You're obviously working that out in ways that make sense to you now, and knowledge is good, usually a very personal perspective too. The people who have responded to you here have given you heaps of their knowledge too, except maybe me. I'm sure you'll have more capable gear one day, worry about technical stuff like that when it really matters, and going in educated will make that process far less intimidating or confusing, and you'll get results with less trial and error. Trial and error is good way to learn too, but you can break stuff. Don't let it all get frustrating and stop you playing music.That's all i was saying, all just IMHO. Good Luck.
The only Barry C i know of is Barry Crocker - do not look that up! and if you are just trolling - so what? - you just copped another paragraph of my drivel, all in good faith too, which is sort of sad if you are just wanting a 'fight', not that i believe that - nobody but me can waste my time, who's trolling who?
G
Greg_L
Banned
Now we know why barry c hates recording. It's because he's a broke mofo.
R
richardosim78
New member
Impedance matters exactly because
there's a voltage divider created by the connection. In this image, your source's out-Z would be R1, and the load's in-Z is R2. I think it requires only a grade school level understanding of math to see that Vout goes down as R1 gets bigger with respect to R2, and that if we want as much voltage out as possible then R2 should be a whole lot bigger than R1. If R2 is ten times R1 then the output voltage will be 10/11 of the input, which is less than 1db down, which we consider to be negligible, and thus the 10:1 rule of thumb.
But this is for purely resistive components. If either the output or the input include reactive (inductive or capacitive) components, then which ever "R" they represent above will actually be frequency dependent. Most active devices can be considered to be purely resistive because any reactive part of their impedance contributes very little in comparison. We can't go too wild with this, though, as there usually is some largish capacitance in series (AC coupling capacitors) with R1, which gets bigger for lower frequencies, so that if R2 gets really small, we can lose bass response.
The cables we use to connect our equipment are capacitive, and in parallel with R2 such that R2 gets smaller for higher frequencies. Therefore, if R1 is very large we can lose some treble.
A passive guitar pickup has a pretty large resistive component but is also very inductive. Therefore, R1 starts kind of big and then gets a whole lot bigger at higher frequencies. Therefore, if R2 is smallish, we lose a lot of treble. Of course, in most passive guitars, R2 is actually more like the parallel total of the values of the pots in the guitar, so the math gets a little tougher, but basically we want the input-Z to be as big as possible so that the Vs and Ts on the guitar itself are the main factors in the overall tone. As for this assertion that most people can't tell the difference between plugging into a 1M vs 56K, well...most people are dinks. For most passive guitars, there will be a pronounced difference in the top end. I can't imagine anybody would argue they don't hear a difference when they turn their T knob down to 6...I suppose, not everybody really wants all of the treble possible out of their guitars, but there is a big difference.
I still think there's something fishy with the specs as stated. Honestly, I think that this is probably rebranded cheap crap from somewhere in the orient, that the brand owners don't actually have a clue what it is, or how it works, or what any of these specs mean.
The fact that it is cheap doesn't really have to mean that it is particularly inferior in audio quality. It is extremely cheap and easy to make a damn good line mixer of this sort. It's really just some resistors - which are practically free - and a dual opamp - of which the really good enough ones are also pretty damn cheap. It doesn't take any fancy engineering to "develop" the circuit. It's right there on the datasheet for the opamp, a circuit that's been tried and tested and used in damn near everything for decades now. The "hard" part is the power supply, and even that's not that hard. Again, the methods to do it right are old and well known and those components don't cost that much either. So, the electronics part of this is less than $5 for you or me buying in singles, and for a factory in China buying millions at a time...
The real expense comes in the jacks especially, and maybe the pots next. I wouldn't expect even the cheapest to really degrade the audio performance all that much at first. The cheaper parts are more likely just shoddy, and more likely to fail sooner, and that's where you're going to see the big problem with this cheap thing. The company is likely not spending much on QA, so the thing might just show up broken to begin with, and I would worry about long term reliability. How long will it take for those cheap jacks to go intermittent, or the pots to get scratchy?
What are the legitimate uses for such a thing? Since this is 2014, and this is homerecording.com, I'd say the most common use would be for "analog summing". It's exactly what those fancy (expensive) boutique summing mixers do. Run 4 stereo stems out of your DAW, plug all the Ls into the Ls and all the Rs into the Rs and plug the outputs into whatever you're mixing to - usually a couple of inputs on your interface. In the 90s things like this were often marketed to keyboardjists/synthesists. We would connect the stereo outputs from our various MIDI sound modules into this simple little thing and control EQ and usually even level from the individual boxes themselves. You really can use it to connect whatever to whatever, as long as you watch things a little bit. I might not plug any passive guitars directly into the thing, but the output of about any guitar pedal should be fine. Most "line level" sources should also be fine. Most microphones will be fine.
Gain staging is always a concern, of course, but sometimes we have to do what we can do. An SM57 is not a particularly sensitive microphone, so sure maybe it "needs" 60db gain to get up to line level. We would very much prefer to get that gain as soon as possible so that we're only amplifying the first stage or two worth of noise. But sometimes you can get away with getting the gain a little further down the line. If you must, you must. If you're recording to cassette, you'll probably never notice the difference. Recording to digital...well maybe it'll just sound like you recorded to cassette...
When somebody comes along and asks a question like in the OP, I make the assumption that they want to actually learn something about the underlying concepts so that they can make better informed decisions about their purchases. I feel that is pretty important, actually, whether the budget is $15 or $15,000. I can understand explaining the real science behind why this or that might work better or be less than ideal, but just saying "No, that's the wrong way to do it" doesn't really answer the question.
I'm not completely convinced that it's going to be the worst thing that anybody has ever done to try to record something important to them. It has potential to be kinda decent. The device itself can be used for any number of different applications with acceptable results. It is, to an extent, expandable. Save up some dough and buy something like a Nady PRA-8 for $99, plug it into this thing, and you've got something on par with the Mackie 8 channel mixers for $115. No eqs, but more flexible in some ways...
well, i'll give it a try with that crappy thing anyway.. thanks
G
Greg_L
Banned
You were going to all along. So why make this thread?
R
richardosim78
New member
i wanted to know more about it.. isnt that obvious??
G
Greg_L
Banned
No, not really. You wanted to be told what you wanted to hear.
R
richardosim78
New member
50/50 i guess...
G
Greg_L
Banned
So are you taking your alleged daughter off the grid with you?
R
richardosim78
New member
she will choose later when she grows up a bit.. i hope she wont waste her life as i did..
i was too lonely to avoid that.. i hope she will do better...
other things r too personal..
G
Greg_L
Banned
I'll humor you for a moment and pretend that this is real.
Do you feel that you are being a responsible father by not having a job, a life, any friends, income? What are you teaching her? How are you providing for her? More importantly, how are you making her life better by being what most people would call a "deadbeat"?
R
RAMI
Guest
R
richardosim78
New member
i think u r one of 'them'..one of those from that closed circle that became very big in members nowdays.. so u know that im right...