3w Amplifier before RCA splitter?

[Arcygenical]

I'm splitting a ~2w RCA signal to 4 sets of plugs. Yes, I know ~2w hardly tells the story of my audio signal, but I'm using a USB Optical>RCA DAC purchased for cheap on eBay, sadly it doesn't list the outspecs of the DAC... All I know is that it pulls 500ma @ 5v via ammeter.

Basically, my setup is as follows:

RCA 1 + 2 > Power Amp (A/B) R, L Mid/Tweeter Crossover.
RCA 3 + 4 > Power Amp (A/B) R, L Channel 10" Subwoofer Cones.
RCA 5 + 6 > Second Power Amp (D) 15" Subwoofer Channel.
RCA 7 + 8 > Spectrum Analyzer.

Now, the spectrum analyzer isn't sensitive enough to pick up the heavily split signal. Unplugging the amplifiers rectifies this issue and the SA works flawlessly. I'm wondering if putting a cheap 3w USB amplifier in-line with the spectrum analyzer will greatly mess up the rest of the sound stream.

I'll be using a cheap ebay module
Basically, This Guy

I'm wondering if it's going to mess up the RCA signal path since it's connected to the same case ground / RCA negative connections as the rest of the system (the amps have their own grounds too)

Anyone have any suggestions/input?

 

[Mohonri]

You shouldn't have to worry about the grounding--in the current setup, they're all sharing a common signal ground through the splitters anyway, so you're no worse off by introducing an amplifier. The amp on eBay looks like it has the proper decoupling capacitors, so I don't think there's a problem.

The amp from eBay should work for you, if indeed it has the oomph you need. What are you planning to use to power it?

 

[Arcygenical]

I'll be using a the 5v line from my PSU that measures around 5.11v under full load. I'll be throwing a few nice filtering caps and a very basic clean up shunt, in-line with the power source just to help with any possible ripple noise... Since this 3w amp is going to be the "pre-amp" feeding multiple 1000w rms amps.
lol.

I just don't want to introduce any more noise than I already have.

 

[Fenris_Ulf]

Knowing what these little amps are like, you'll probably have a voltage gain of 2 and enough current to split it out to 50 devices. It will be about twice as loud and there might be a slight degradation in sound quality (which happens anytime you insert something into the signal chain) or there might be a slight improvement if your signal source was overloaded.

 

[Arcygenical]

I'm a moron. I hadn't installed the XFI drivers... I'm now seeing around 4v out from analog line out, hah.

TWO YEARS WITHOUT THE PROPER DRIVERS.