Can room acoustics amplify the sound of speakers?

I agree with Stanwal.
If your room isn't accoustically treated at the first reflections, and preferably the second also, the nodes can make havok of the imaging and it will fall apart at high SP's.
If you don't have enough headroom in your amp this can also cause the image to fall apart at loud SP's.
And, if your speaker isn't capable of filling the room with said SP's, it will break apart.
And a combination of all the abouve will be evident

It is possible that the colorations you hear at high levels are actually present at lower levels, but are below the detection threshold.

In a small room, you inevitably have lots of early-onset reflections, and in general early-onset reflections are more likely to be detrimental than later-onset reflections. In my opinion it makes sense to address this situation at the speaker design level, rather than relying solely on room treatments, because room treatments are not frequency-selective enough to target the types of problems loudspeakers tend to have in small rooms.

For instance, if your tweeter has much wider dispersion than your woofer(s) in the crossover region, the reverberant field in your room will have excess energy in the lower treble region, at the lower end of the tweeter's range. This is more likely to color the tone and degrade the clarity if the reflections begin arriving relatively early, as is the case in a small room. Absorptive panels cannot target just that frequency region; they will absorb broadband, and enough absorption to eliminate the coloration may also make the room too "dead". Some absorption will probably be beneficial in your case, but in my opinion it's easy to over do it in a small room.

The fact that you're using the word "amplify" makes me think that you may indeed be getting emphasis in the 3-4 kHz region from the reverberant field, as that is where the ear is most sensitive so extra energy in that region would seem to amplify things.

Imho, ime, ymmv, etc.

Duke
dealer/manufacturer

Stand in your room and clap your hands. If it echoes, then the same thing is going on on every note that comes out of the speakers.
Keep it simple at first and progress by process of elimination.

I've chased and solved the very same problem in my own system and it wasn't the room acoustics ... see if this is similar

You system sounds wonderful 99.5% of the time ...it does everything right from sound staging to top to bottom coherency ... nothing sticks out or glares in the midrange and extreme's ... top and bottom end are extended and well defined

Everything sounds fine until there is a very brief and powerful peak/passage (Crescendo) called for, that demands a large draw of current for a very brief period

Hint ... it isn't the amp clipping or it would be shutting off briefly

For that brief nano second or so ... the whole presentation goes to Hell in a Hand Basket ...

The sound stage shrinks to a small ball in between your speakers ... the sound congels ... it ESPECIALLY sounds like someone is shouting rather than singing ... and dynamics get looped off on the trailing edge ...

You also notice that this happens only on PEAKS and is not connected or related to any normal upper octave frequency brightness

It's like you're driving down a very smooth highway at a high rate of speed and you hit a deep pot hole abruptly ... and it's over that quickly

The problem of the brief shouty-ness is probably caused by the OPAMPs in the CD player's SS output stage not being able to deliver enough current to drive the IC and the load on a strong PEAK and they loose their linearity momentarily when placed under the high demand for current during the PEAK/Loud passages

This is not an issue of impedance or voltage mismatch between components ... it is the Op Amps distorting because the can't deliver the current required in that brief high demand period

When the music becomes demanding, the OPAMPs will loose their linearity for a brief moment, distorting and that distortion then confuses and causes the Negative Feedback loop, to oscillate and ring while trying to maintain the signals integrity from input to out put

The negative feedback loop try's to maintain the signal from input to output but when the chip OP Amp run out of deliverable current for that nano second on a PEAK and distorts .. the negative feedback loop picks up the distortion and starts oscillating and ringing for that brief moment that the Op Amps can't maintain the needed current to dive the intergrated and are out of linearity

The ringing which is very brief, and only on the peaks of demanding passages is perceived as "Shouty-ness" and seems to be pretty common with CD players that use SS output stages with chip OPAMPS ... although I don't think many are aware of it or blame the problem on something else

Here's more proof ... no matter what volume you are listening to your system at ... low, medium, or high ... this distortion and shouty-ness will be present on all strong peaks as it is the Op Amps in the source causing the problem and sending the distortion to the next component ... the intergrated amp ... and not the intergrated amp's lack of power because the distortion is still present at low listening levels on the peaks ... so the amp can't be running out of power at low and medium listening levels

If this sounds like your problem ... tell me what you use for a source and I might have the solution ... and if this does not sound like your problem ... it's a good thing I put on my Flame Suit and Eye Protection on

Zmanastronomy, good advice.