Normal and high preouts on a preamp

[steelglam]

If a preamp has two sets of preouts, one marked "normal" and one marked "high," I'm wondering if someone can help me understand the difference between the two.

For instance, let's say that you wanted to hook up two power amps to the preamp, would you plug one into the "high" preout and one into the "normal" preout, or will that cause a problem?

Conversely, if you wanted to hook up one power amp and one powered subwoofer to the preamp, would you plug one into the "high" preout and one into the "normal" preout, or will that cause a problem? If it will not cause a problem, which preout would the sub go into and which one would the power amp go into?

Thanks.

 

[whoaru99]

I think you need to indicate the brand and model.

Without knowing that I think it's hard to say what high and low means.

 

[steelglam]

I think you need to indicate the brand and model.

Without knowing that I think it's hard to say what high and low means.

Sure, it's an NAD 1300.

 

[Stuart Pedaso]

Normal output: 50 ohms impedance, 12V max.
High level output: 100 ohms impedance, 15V max.

 

[steelglam]

Normal output: 50 ohms impedance, 12V max.
High level output: 100 ohms impedance, 15V max.

Thanks!

As a follow-up, does anyone know what that means for the questions I asked in the first message in the thread about bi-amping or running a power amp and power sub simultaneously? Can I use both sets of pre-outs simultaneously, given the differences in imepdance and voltage?

 

[whoaru99]

The impedance should have little consequence, but you'll probably need amps that have input level controls to balance the outputs due to the (apparent) difference in voltage.

You could also use simple "Y" cables from either pair of outputs to your amps. Personally, I'd probably use the normal outputs and "Y" cables.

 

[steelglam]

The impedance should have little consequence, but you'll probably need amps that have input level controls to balance the outputs due to the (apparent) difference in voltage.

You could also use simple "Y" cables from either pair of outputs to your amps. Personally, I'd probably use the normal outputs and "Y" cables.

Got it, that makes sense.

I have to ask, then: what is the purpose of having these two sets of preouts: one "high" and one "normal" gain? Kind of defeats the purpose that I assume most people have in mind when they want something with dual preouts: to biamp or run a sub + power amp.

 

[whoaru99]

Not sure the exact purpose. I can only assume the "high" output would be used with amps of lower than the typical input sensitivity.