4 channel amp question & line/preamp question.

**Profozone** · 08-18-2007, 10:47 AM

As the subject implies, I have two questions.

The first relates to levels. I always thought that line level was really low, like a volt or so and that preamp levels were a bit higher and that a preamp was needed on a line level to drive an amp to speaker levels. After searching the web a bit, I now think that preamp levels are either a little lower than line levels or they are about the same. In fact, I think there is no fixed firm voltage/current values attached to these.

The point is auto amplifiers seem to list preamp inputs so the question is, does that mean it's all right to just connect the line level outputs of my SB live 24 external to the preamp inputs of a regular auto amplifier. I believe it is. In fact, in the next picture the amp which lists preamp inputs actually has them labeled as line level input on the back panel.

The next question is: Am I correct when I say that I should be able to connect say the front outputs on the SB to the left and right line level inputs on Channel A of this 4 channel amplifier and the rear ouptus of the SB to the left and right line level inputs on channel B of the amplifier and I should then have control of both fade and balance on a 4 speaker system using the SB? Again, I think so, but I would appreciate some confirmation and opinions on both subjects.

Thanks.

**2k1Toaster** · 08-18-2007, 01:07 PM

Well not sure about the whole voltage thing as me and audio dont get along...

But, yes it goes straight from soundcard to amp. You can put processors on there, but that is for the high end.

And as for sound, yes. That is absolutely correct. Each 1/8" port, has 2 channels. So 1 plug into Port #1, give you Front Left ad Front Right, and the secong plug into Port #2 gives you Rear left and Rear Right. So all this can be controlled individually.

**Felix509** · 08-18-2007, 02:52 PM

Well, I do not know about the whole Front and back thing, but will make a comment on voltages..

I think the words line out/preamp are interchangeable in most respects, it is kind of like having a moonroof or sunroof maybe, depends on the person writing the specs.

The amp has an input sensitivity adjustment. On the amp in the picture it will accept preamp voltage between 0.2 and 5 Volts. The reason for this is to be compatible with a wide range of sources, some with high output voltage, some with low.

I am not sure what voltage out your soundcard has, but i image it is relatively low, .5-1.0 volts maybe, but i imagine it is withing tte input range of most amplifiers...

OKAY, hope that helps..