Hi, I have been trying to create a circuit that inverts an ac audio signal with an op amp (lm833). But I don't know where to start. Can anyone help me create a circuit that would work?
Does a Google search for this phrase: "op amp unity gain inverter" bring any circuits which look useful ?
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That might work, but would I need a negative supply voltage for that circuit to output an ac signal? Because it would be easier if it was just a positive supply voltage, but if it is the only way then I will do it with the two supply voltages.
It depends on if you want to invert the DC bias on the AC signal.
Don't audio signals just oscillate around 0 volts? so there wouldn't be any dc offset?
In a past life I use to play a lot with stompbox for electric guitar signal. For those, you don't need a negative DC supply. The idea in absolutely no electric engeneer words is the following.
Usual stomp pedal work at 9v DC. You bias your OpAmp at 4.5v (1/2vcc). Once in this state, the "bias" will act like a signal carrier for your AC signal. Your AC signal ground will then be the 1/2vcc bias. In this example, 4.5v. The AC signal will then be able to swing up and down around the Bias voltage. Since in this example, the power is 9v, the AC signal can travel up and down as long has it swing do not overshoot 9v DC in the positive region and 0v DC in the negative portion. An electric guitar signal of 100 mV AC will then swing around the 4.5v DC and move between 4.4V and 4.6v.
Now in reality, OpAmp are not perfect. You will not have 0 to 9V of margin but less and this depend on the IC. In stomp guitar, if you exceed the rail voltage (a swing above 9v) then you get distortion and rock music!
If your AC audio signal is bigger than a couple of hundreds of mV, then it will be more complicated.
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Maybe you should tell us what you're trying to accomplish. Is this a line-level audio signal, or a guitar signal? Or something else? Is there an Arduino involved?
And analog inverter can be made with an op-amp and two equal-value resistors (10K - 100K would be common for line-level audio). Like most op-amp circuits, the "basic design" assumes dual power supplies.
If you don't have a negative supply, or if you are feeding into an Arduino the signal needs to be biased (or the Arduino has to be "protected" from negative voltages). The Arduino's ADC can't read the negative half of an AC audio signal and it can be damaged by negative voltages.
Two more equal-value resistors can make a 50/50 voltage divider for the bias which is applied to the + input (instead of grounding the + input).
If there is no Arduino but you have a single-supply the bias can be filtered-out with a series capacitor and a resistor to ground. Then the AC audio will swing positive & negative, even without a negative power supply. There is also usually a capacitor on the input to "isolate" the bias from whatever is connected.
Can you explain WHY you want to do this? The inverted signal would LOOK (on an oscilloscope) and SOUND exactly like the original.
Anyone who has used an op amp inverting amplifier to couple an pos/neg AC signal to
a single ended circuit knows you need a 50/50 voltage divider (also mentioned by DVDdoug) to bias the signal midpoint (Vcc/2)(which in the case of an Arduino is 5V/2=2.5V). That being said, if you have the 1uF series coupling cap on the input, the circuit works quite well. I have built many op amp circuits, both dual-ended and single ended and with dual to single-ended converters and it is very straight forward and predictable. I actually built a 10-band graphic equalizer (~40 yrs ago) using solely LM307H metal can (NS H08C package) (now obsolete)using Walter Jung's Audio IC Op Amp Applications cookbook and high quality mica caps and 1% resistors and it was found by a certified audio engineer to be studio quality, all this while know practically nothing about op amps and simply following instructions, so you should have no problem building your circuit. If you're wondering why I chose that op amp, the answer is the electronics store (Priority One in Southern California, USA) had them on sale (normally $3.95/EA, on sale $0.25/EA, so I bought their entire stock of 166 of them and it lasted me more than 20 yrs. I gave the last 66 of them to a Stanford EE student.
LM307H
If you do the math, I paid $41.50 for what today would cost $3,922.48.
It's to feed into a 2 channel amplifier where 1 channel is inverted and the other is normal to get double the voltage difference across the outputs.
Can you post the schematic of that circuit ?
For what? Bridge amplifier?
Some do and some don’t. If you want to have it work with your circuit with the negative supply on the ground then you need to add a bias in order for it to work.
No you are very badly informed.
Come clean show us your circuit, show us where the Arduino is show how it is wired.
"No you are very badly informed."
Yeah, I was thinking the same thing.
If you mix an inverted signal with a normal signal you get 0V out.
If you want to double it you use a dual-ended noninverting amplifier running off the same supply rails (or higher, depending on the input signal amplitude) as the source signal with A=2
(R1=R2)
He's gone quiet. Probably in a hurry in the morning to get to school. 
When we get details of what these audio amplifiers actually are - with Web links or full documentation, we may get somewhere. 
Until then, total time waste.
Good example of why we need to know the reason rather than how the OP THINKS it should be done.
TR1 - any high gain audio npn eg BC108/9
all caps chosen to give the required bass response eg 100uF
Supply decoupled with c 1000uF across the rails.
The resistors on the base in that circuit should be biasing the base at around 2V to maximize signal swing - with 2V bias on the base the emitter can swing around 1.4V, the collector around 3.4V.
With the bias at 2.5V on the base the emitter is at 1.9, collector at 3.1 and there is very little headroom, the transistor nearly at saturation. I'd suggest 2k2 and 3k3 for the base resistors will improve matters.
When we get details of what these audio amplifiers actually are - with Web links or full documentation, we may get somewhere
JAOA (jUST ANOTHER OP AMP)
LM833
Clearly you need to study op amp applications.
If you sum two ac signals (one of which is inverted) they cancel each other. This is the basic
concept of noise cancelling and how a small midwest town cancelled the noise of lumber
mill by inverting the signal and amplifying it enormously.
If you just want to double the amplitude, that's called a Gain of 2 non-inverting amplifier,
which requires a dual power supply (bipolar ?)
So basically, nothing you have said in this post makes any sens.
Hi,
If you look at the data for the LM833, you will find it is a high performance audio op-amp.
It needs +15V and -15V supply.
Do you have to use this op-amp and what is the overall application?
Is this a school/college/university project?
Google;
single ended ac inverting op amp
For example;
http://www.ecircuitcenter.com/Circuits/opinv_ss/opinv_ss.htm
Thanks.. Tom... 
