Audio Interfact with RCA Output and HiFi Speakers?

[jm240]

Hey all,

I have a hifi with standard speakers that connect to the main hifi unti by connecting some exposed copper wire then screwing the red and black connectors down.

I have an audio interface (Focusrite Scarlett) with RCA output.

I have attached a picture of my speakers, they are Gale Mini Monitor MK2 Speakers. I'm not sure though if the connections on the speakers can be used as RCA as well?

Can I use these speakers as PC Monitors?

Really would appreciae the help, thanks

 

[lucid]

RCA/phono line level signals don't produce sufficient power to drive a Hi-Fi loudspeaker. At maximum volume level a line output socket (RCA/phono) produces 1.4V and negligible current. Your stereo amplifier will produce anything up to 20V and 2.5 Amps of current. The difference in scale is a speed bump to a tower block.

The way to use your Scarlett is to connect line out from it to a line input on the Hi-Fi amp. The amp with then take the tiny line level signal and multiply it up sufficiently to drive the speakers just as it does when playing CDs/MPs or whatever you play through the Hi-Fi right now.

If the Hi-Fi amp doesn't have inputs for other sources then that's what you need to change. Buy one designed to drive 8 Ohm speaker and with multiple inputs for external sources.

 

[jm240]

RCA/phono line level signals don't produce sufficient power to drive a Hi-Fi loudspeaker. At maximum volume level a line output socket (RCA/phono) produces 1.4V and negligible current. Your stereo amplifier will produce anything up to 20V and 2.5 Amps of current. The difference in scale is a speed bump to a tower block.

The way to use your Scarlett is to connect line out from it to a line input on the Hi-Fi amp. The amp with then take the tiny line level signal and multiply it up sufficiently to drive the speakers just as it does when playing CDs/MPs or whatever you play through the Hi-Fi right now.

If the Hi-Fi amp doesn't have inputs for other sources then that's what you need to change. Buy one designed to drive 8 Ohm speaker and with multiple inputs for external sources.

Thanks a lot for that lucid. Was really informative and educational for me.

I did think that was how I'd have to hook it up i.e via the Aux-In on the Hifi but I thought my interface had PreAmps in them but I'm guessing there aren't any for the line out - only amps for the line in.

My Hifi unit is really big and clunky so I don't want it on my desk plus it needs another power source!

 

[lucid]

You were right first time. The interface does have pre-amps. These handle the very small line level signals, and that's what gives you control over input gain and output volume.

What the interface doesn't have is power-amps. That's the circuit(s) responsible for taking the very small signal at line level and increasing the power and current so that it's strong enough to drive a a loudspeaker.

As I see it, you have at least three options open to you.

The low cost solution is some really good quality and very well shielded phono cables from the interface to the stereo. The shielding is important because that's what prevents the cables picking up interference that manifests as hum. The long cables would allow you to have the Hi-Fi main unit off the table.

The second option is a small desktop amp. If you don't need it too loud then one of the small T-amps might do the trick. This means disconnecting the speakers from the Hi-Fi when you want to use them with the interface. The thing with T-amps is you have to take the claimed power with a very large pinch of salt. Divide any figure you see by 3. That's because they measure absolute maximum power based on a much better power supply than they ship with and the figure includes a huge amount of distortion, so it's not really usable.

The third option is powered (active) desktop speakers.