Amplifier sensitivity for RCA and XLR input

[Macleod]

Hello,

I am on the way to design an amplifier for input signals coming from RCA and XLR connectors.

I am wondering what is the sensitivity to target for those two inputs as my amplifier may provide 100W max. I am targeting something like x30 gain. Is it correct?

I couldn't find any reference document for the maximum level acceptable in both case.

So if you are aware of :
- maximum level in both case
- recommended sensitivity
- maximum common mode voltage for XLR

Any comment appreciated!

Best regards

Laurent

[AndrewT]

domestic use or commercial use?

For domestic use, we usually see sensitivities between 100mVac to 1Vac for full power.

For commercial use, we usually see +4dBu to +10dBu.

[Macleod]

Maybe I can be more precise on my request.

As in put stage will be connected to RCA or XLR, I need to know if I must apply various attenuation according to the input selected.

I am ok to have 1V for full power using RCA.

Does it make sense to have 1V for fullpower using XLR (1V is differential in this case)?

[Macleod]

Forgot this answer : it is for Hifi use at home.

[AndrewT]

design your sensitivities to suit the outputs of your domestic sources.

[Macleod]

Yes, if it was for me alone, I would just do like that. But the aim is probably to make some of them and I would like to be sure it is compatible with any symetric/asymetric input.


When you say 1V, is it for RCA or XLR?

[Gordy]

You want to make some of them? So you want to manufacture as a commercial design, yet you do not understand sensitivity?

If you are going professional / commercial you need to pay for design assistance. Perhaps the guys on this forum that help you can take a share of your profit?

Or is this forum a free help-line for incompetent marketing men?

[Macleod]

...?

Couldn't guess it could be seen like that...

It is not for business, I already have a job it is on RF not Audio...

I know what is sensitivity, the level for a given power, max power in my case.

I know electronic (I am IC designer), but I don't know the standards used for audio. And I may change my sources so I need to align to a standard.

The question is on the max level to be encountered on XLR connectors, I have none of those items at home.

Why do I ask here? Because it is DIY Audio a good place to ask questions on Audio. I have asked on a french site, but the response was unclear, less technical guys.

When I said I would like to study an amplifier for my own needs, I proposed to share results (for free!) and I have been asked if it could support symetric input (some of my friends have Cello Preamp and they adjust the sensitivity with strap according to the input). So I am investigating it. But when I go to Spice, I wonder what is the maximum input voltage (should I withstand 2V peak voltage for my input differential stage or not?)

I already asked some questions about triggers, differential input, valves, power supplies and got some answers. I read books and have some others. This last question was not offending for me.

Do you mean I have to pay to have a technical information on a public forum?

[wahab]

Take a 225 to 300mV rms sensitivity in RCA plugs.
For XLR, standard is about 775mV rms, with an overload
margin of +20db, that is 7.75V rms..

[Macleod]

Thank you wahab for your inputs.

7.75V is high. Some attenuation may be necessary for that input.

Will go on investigate that.