Bi-Amp on a budget possible?

Hey guys,

I just started reading about all kinds of amplifiers because I am using volumio on my Raspberry Pi B with a Panasonic SA-PM28 Hifi-System and i want to get rid of the bulky standard reciever! The transformator is always buzzing and i dont need Tape/CD/Radio, when using volumio.
Sadly though, the speakers do use 2 channels, one for high and one for low. So to use these really good speakers I need a Bi-Amp, which I frankly know nothing about.

The technical specs of the speakers are 70W@6Ohms for each, High and Low.
So I need to know if it(for example) would be possible to get 2 amplifier boards with 100W2 each. Or ofcourse one board with 4100W. Ive read a lot about the TPA3116 boards here, but sadly I couldnt find an 100W or 4 channel version.

So in short, here are the things i need from an amplifier:

  • at least 3 analog inputs, switchable (hard- or software/Pi)
  • 4 Channels at 70W@6 Ohms
  • really clear and good, but not earth shattering sound
  • cheap is always nice, since I am studying and on a small budget
  • volume, bass and treble control would be neat!

So would this be possible? Or am I overlooking something?
An what would be the best way to achieve all this?
If you information on the SA-PM28 there is even a Service-Manual linked on google!

Two of these perhaps? … 3aa5d9b0b9

Wow I’ve never seen a mini system with separate low/high speaker outputs.

Rotel amps certainly used to have 2 sets of speaker outputs, but both outputs delivered the same output i.e. not separate low/high frequency.

I’m really not sure how you would use these speakers (which must not have crossovers) with ordinary amps… you might end up spending more money trying than just using different speakers and a normal amp.

Hey thank you very much for your input on this.

I read a lot about the needed active crossover for such speakers, and i think it is i bit to much for a first audio project. So I guess the standard amp needs to stay. (perhaps I find some other solution for the transformator buzzing.)

Maybe its possible to convert the cassette deck to an AUX connection, I read somewhere that this is possible…

So can you recommend a good and cheap DAC for the raspberry pi?
I would like to connect it over the i2s interface, but it doesnt need to fit on the pins, since I am using a custom case.
Ive read a lot about the ES9023 and its very cheap but without MCLK its not going to work, right? So is somethin like the Hifiberry-Board a better choice?

For the amp, have a look here ( if you’re not afraid by diy) :
For the DAC, one base on a es9023 works perfectly if you choose one with on board clock (hifiberry, or on the site I gave).
For your loudspeakers I’m not sure to have understand, but bi-amp won’t provide a huge difference (even no). You’d better choose a good 2x way amp with good power supply and a preamp to select the input. But maybe I didn’t understand your need… :wink:

There’s a company called Xkitz that makes a couple of nice bi-amplifier boards, a 40W and a 125W, at a decent price: … 2-p-6.html … -p-17.html

They’re kits, but I think you can get them pre-built also.

Bi-amp’ing actually produces a huge bump in sound quality because you’re replacing the highly distorting passive crossover with an active crossover with distortion numbers down below .01% THD.