Need Help Audio Preamp Circuit

[TecIE]

Hi



I came across this preamp by doing a search on this site. I been trying to find a TL071
preamp circuit. This amp was posted by poster Audio guru.

I have a direct upgrade replacement IC that has a lower operating supply voltage of 4.5V-16V
Will this amp circuit work as is with the TLE2071IP upgrade IC.

I like to use this preamp circuit.

I will be using 5.5V for my supply voltage.

Also is the 1k resistor directly connected to pin 7 or is it just connected to the positive supply
rail.Please explain. Will i need to add or change any parts for the circuit to be functional at
the supply voltage of 5.5V.



Datasheet.
https://www.electro-tech-online.com/custompdfs/2013/08/tle2071-q1-1.pdf

 

[TecIE]

Can someone Help.

 

[cowboybob]

Hi...Will this amp circuit work as is with the TLE2071IP upgrade IC....QUOTE]

Not according to the datasheet.

For single supply Vcc situations, TI recommends using the "TLC" or "TLV" series chips.

 

[Nigel Goodwin]

Fit the chip in a socket and try it, although what are you hoping to gain with the later chip? - I suspect you will see VERY little (or none at all) difference.

The TL07x are really extremely good chips.

 

[ronv]

You can get a TL081 at radio Shack - almost as good. And yes the 1K is just to the positive supply.

 

[TecIE]

Hi Nigel

The TL071 has a minimum supply voltage of 7V

It has TLE2071IP
Has a minimum supply voltage of 4.5V
Lower noise ratio.11-14
Lower supply current.1.6mA at 5V
Lower off set voltage
Higher slew rate

Other then that there's really no difference.
I need to use 5.5V.This is the reason to use this IC.

Thanks for your input.

 

[TecIE]

Thanks ronv for your INput.

I would use it if my voltage supply was 7V
But i need to use a 5.5V supply.The TLE2071
Supplies this and lower voltage.

 

[TecIE]

Hi...Will this amp circuit work as is with the TLE2071IP upgrade IC....QUOTE]

Not according to the datasheet.

For single supply Vcc situations, TI recommends using the "TLC" or "TLV" series chips.

So your saying the TLC series is a direct replacement for the TL071X chip.And i could just use that one.I also look at TLC071IP at TI.It didn't state this in the Datasheet.
That it was a direct subsitute for the TL071X. Thanks for your input.

 

[ronv]

This one is real good and swings close to the rails.

https://www.electro-tech-online.com/custompdfs/2013/08/opa134.pdf

I would make R1 5.1k

 

[alec_t]

But i need to use a 5.5V supply.The TLE2071 supplies this and lower voltage.

Are you using a single supply? The TLE2071 specifies a dual supply, e.g. ±5.5V.

 

[TecIE]

This one is real good and swings close to the rails.

https://www.electro-tech-online.com/custompdfs/2013/08/opa134.pdf

I would make R1 5.1k

This looks good.The only thing is the supply current at 4mA is to high for battery operated circuit.

I would like to have the suppy current at 1.5mA or lower. For battery supply circuits at 5.5V.
To not drain the battery faster then needs to be for portable devices.
Is there any such audio amp like the OPA134 But with a much lower supply current.If Thats possible to get.

 

[TecIE]

Are you using a single supply? The TLE2071 specifies a dual supply, e.g. ±5.5V.

Yes! I'm using a single supply at 5.5V.
ronv suggested a OPA134 looks good.But the supply current is to high for battery use.
I like my supply current to be 1.5 or lower when i use batteries for my power supplies. Any suggestions on this.

 

[audioguru]

The TLE2071 minimum supply is plus and minus 2.25V so it will barely work with a single 4.5V supply if its input is biased at half the supply voltage.
It will work fine with a single 5.5V supply in the TL071 preamp circuit.
Its gain is very high as a mic preamp so I doubt if its inputs will exceed the input common-mode voltage limit.

 

[rumpfy]

Dont think about using general purpose op amps for audio work. Generally they are too noisy.
In processing low level, low noise signals use a proper audio type op amp. A typical type is a LM833.

 

[Nigel Goodwin]

Dont think about using general purpose op amps for audio work. Generally they are too noisy.
In processing low level, low noise signals use a proper audio type op amp. A typical type is a LM833.

Very sorry, but that's complete and utter nonsense - almost all opamps in top end mixers are normal standard opamp types.

The TL07x series make exceptionally good audio stages, and replacing them with supposed 'better' ones generally makes no difference.

 

[ronv]

Lots of them out there.

Take a look at the LMV651 from TI.

 

[audioguru]

The old LM833 is a good dual audio opamp designed to be the preamp in a record player or in a tape recorder/player (remember them?).

Some "audiophools" use an OPA2134 dual opamp with distortion at the extremely low level of 0.00008% and add a class-A load to reduce the tiny amount of crossover distortion that cannot be heard anyway.

 

[TecIE]

Audio guru
Would this work

Its a battery powered mic preamp

LMV721 Setting it up in a Noninverting configuation. It has low noise. Low power and low current supply.
With a single supply rail to rail. And using a Power supply of 5.5V.

Datasheet
https://www.electro-tech-online.com/custompdfs/2013/08/lmv721-n-1.pdf

 

[audioguru]

The LMV721 opamp makes a good mic preamp. Since it does not have the low current Fet inputs of the TL071 that I use then use the inverting circuit shown on the datasheet of the LMV721.

It is tiny and is surface-mount. Can you connect to it?

 

[TecIE]

It is tiny and is surface-mount. Can you connect to it?

Yes! I could. I'll use this enclosed SOT-23 adapter Board.

Since it does not have the low current Fet inputs of the TL071 that I use

Is this the reason why you are using the TL071 in the non-inverting set up.Because of the low current input.Do to the Jfets.And With the electret mic.

And the LM721 uses a bipolar transistor input.So its better to use this amp in the inverting set-up as in the datasheet.If im wrong about this,Then. Please explain!

Can i use the circuit in post #1 with the high gain as you have it and the part values you have and using lmv721 in the inverting set-up shown in the datasheet.What parts will i need to add and change
so it works propertly with the inverting set-up.And with a 5.5V power supply.