Preamp with piano 2.1

[Swza]

Hello, I'm receiving a piano 2.1 today.  My system currently is Mcintosh 2105 amp and mx113 preamp then off to some bookshelf speakers and a rel sub.  I was wondering if going to the mx 113 preamp from the piano 2.1 would be ok or if I should send it straight to the 2105 amp instead and bypass the preamp.  Would sending the L and R channels to the preamp while the sub output goes straight to the amp cause any problems as far as timing or volume?  I'll be using Moode audio to set the piano 2.1.  Seems like the volume for the mains and the sub won't be matched if I send the L and R channel through the preamp.  And is it safe to send the piano 2.1 straight to the amplifier?  Thanks

[cjf]

Hello,

 

So it appears that the McIntosh equipment mentioned is on the older side. In looking at the specs of the Amp I see it has an Input Impedance of 200ohms 😲 which by today's standard is very Low and not ideal. But...It appears that the Output Impedance of the PreAmp is also 200ohms so they match up nicely there.

 

If I were a betting man I would say going straight to the Amp from the DAC would offer a large bump in SQ for you....BUT...only if the DAC and Amp play nice together.

 

It's possible that you might run into issues going straight to the Amp from the DAC due to a few factors. One being that very low Input Impedance of the Amp and the unknown Output Impedance of the DAC. Then there is the question of how robust the circuit is in the DAC to handle a large mismatch of Impedance at this connection point.

 

I would try it anyway but would not be surprised if the outcome is negative. On the other hand, if it does work you might be quite surprised at the difference bypassing that PreAmp could bring to the table.

 

But if it turns out that you do need to go from the DAC to the PreAmp there are options to handle the volume control portion. In this scenario, if it were me, I would set the volume knobs at near max for both the DAC and the PreAmp and instead control the output level using a good digital volume control. You would of course need to also volume match the Sub to the main speakers via its own vol knob so that all speakers are outputting at the same level depending on whatever position the digital volume control knob is in.

[Swza]

Hello, 

thanks for that thorough response. I ended up going straight to the amp from the piano dac and matched the sub using some measurements from REW and my ears then created filters on the low end and implemented them with camiladsp and it sounds really good, I’m really impressed with this $50 item. Having a low pass and high pass filter on the dac has really cleaned things up below 100hz and the measurements show that.  I’m using a digital volume control on the mconnect app and streaming qobuz. 
thanks again for your insight and suggestions.