Actually what baffled me was that such a tiny setup of my friend could make the quadrals sing with a source fed by a mp3 song over Bluetooth. Whereas in my case I used the CD directly with OPPO 103d to feed the AVR and still the sweetness n loudness were missing.
That’s when I assumed that an amp might be required for my setup.
If mp3 in your friend's room using his amp and sounds so much better than CD direct from Oppo 103D in your room using your Onkyo 818, then the possible factors could be the following.
- not only due to your larger room, but also different shapes, and acoustic characteristics (carpet, wall material, furniture, drapes and curtains etc.)
- locations of the speakers in the room, examples: corner, distance from side and back walls, toe in angle etc.
- wiring error.
Even if all of the above are good, the biggest factors such as those listed below can easily explain your experience:
Different rooms - acoustic characteristics will be very different.
Different time - auditory memory of humans are short (longer than 5s is too long) and unreliable.
Different listening level - even 1 dB difference can make a difference.
Different source media and player - Comparing the same music recording/mastering in different formats, that is mp3 and CD is bad, if the source music is different, that is different songs in different places, that is much worse.
Is it possible to borrow your friend's little amp? That would be easiest way to find the truth, but to me, and I think others such as KEW and ADTG, will agree that any attempts to compare loudspeakers in different rooms at different time using different music and formats are futile.
If you have some spare time, below is a good read for you before your next serious listening comparison session.
https://hal.univ-brest.fr/hal-00638418/document