Bass leaves after amp warms up?

Acoustic reflex seems like a natural defense system against what I have read where 80-85 db is the general limit for safe listening without causing damage to hearing.

It is very possible that when sound seems to change systematically over time, at least part of it is due to our hearing senses adapting or changing as needed.

We tend to think of many things like this as a constant, but no doubt people react differently to things at different times. WHy would hearing be any different?

Thanks to the PSB owner for chiming in. I do not doubt both amps used are underpowered to drive the nominal 4 ohm load. Whether that accounts for all that is being heard is a different story.

One might think any 200 w/ch amp is up to the task of driving most any speaker optimally (not just well). One would be wrong. I've had 360 w/ch and 180 w/ch amps that cannot.

The current delivery and ability to double down at 4 ohms matters. If the OPs MF amp could do that, it would likely warrant being in the published specs. That and being a conventional Class A/B type integrated, which most always has physical constraints that limit what can be done with power supply in close proximity to pre-amp circuitry, I am very confident that it does not.

I disagree with hearing perception changes
Simply put the bass when working has punch,heft,depth & moves air while creating excitment & emotion.
After about an hour the bass notes are still there but the kick of the bass drum no longer has the correct punch,the bass does not move air,the bass notes are no longer rounded but flat,etc.

The bass is similar to a Tuba where the notes are full sounding & you can "sing" along with the bass line if desired.This is the foundation of the music that is receding into the background.
I personality think there is something wrong with my electric.I'm having an Electrician come to tighten all the connections as I think something is causing a misfire.

FWIW, I'd just like to emphasize that the impedance curve I linked to earlier shows that the speaker's impedance is in the vicinity of 2.7 ohms at several frequencies in the deep bass and the mid-range, and is less than 4 ohms throughout most of those regions.

Also, I would not attach much significance to amplifier current capability specs, as they usually do not indicate how long the specified current can be sustained for, and my impression is that in many cases that amount of time may be measured in milliseconds.

Regards,
-- Al

Almark what is the conclusion to be drawn from your post?
My MF amp should be adequate @ 200wpc or no