Am I overpowering my drivers when they

Budding enthusiast here trying to figure out why the drivers in my speakers "pop" at medium-high volumes. I've recently decided to explore the world of "new vintage" speakers and amps (70's and 80's era stuff) in 2 channel for listening to music after a few years of 5 channel supported by a Harmon Kardon AVR 320, Axiom M3Ti mains, Axiom 150 center, Wharfdale surrounds, and an Acoustic Research 12" Sub. This setup just didn't have the presence and power for music that I felt I could get with bigger drivers/enclosures. The little Axiom's are impressive speakers with wonderful detail and clarity, but their small drivers/enclosure limit their capabilities. So I hit Craig's list and started my quest to put together an inexpensive yet repectable system using proven and repectable older gear. First I acquired a Carver 1090 integrated amp to power my 2 channel system and have been picking up speakers as I find something interesting and inexpensive. So far the collection includes Pardigm 5SE's, Polk Monitor 10A's, and Cerwin Vega VS120's. I'm also using an Onkyo 7-band EQ and usually have the loudness activated on the Carver. Problem is, at volumes that are just starting to approach "loud" (output on the Carver showing about 40-60 watts and volume knob at about 30%)...and by "loud" I mean you could still carry on a conversation without yelling, but you'd have to speak loudly...the drivers on the Polks (two 6.5" drivers/speaker and a 10" PR) and the Paradigms (one 8" driver/speaker) start to "pop", like they are being pushed too hard. Maybe my expectations are set a little too high, but I thought either of these speakers, with a clean amp like the Carver (it is a clean amp, right?), could get pushed pretty hard before the drivers started to make that "pop" noise that I always associated with a driver that is being driven too hard. The bass level knob is dead in the middle (would that be "flat"?) on the Carver and the two lowest frequencies on the EQ are just a little above the half-way mark (zero). The Carver has a little needle that shows db output, and I think I'm seeing about -20 or so when the drivers start to pop. Both speakers have rubber surrounds on the drivers and they all look good. At medium volumes I'm very impressed with both the Polks and the Paradigms, but I was hoping I could get a little more out of 'em before they started to lose composure. Could there be something wrong with the amp?
The loudness control is intended to boost the low frequencies when listening at low levels; you may be overdriving the bass if you use it , especially in conjunction with the Equalizer. The first thing to do is to turn off the loudness and take the Equalizer out of the circuit. I suspect that that will cure the problem, if it does not then at least you have eliminated 2 components as the cause. To be brutally frank the consumer GEs of this period were pieces of junk and totally useless except for messing up the sound. They use to cost about $200 at a time when serious pro equalizers ran $2000. Then and now equalizers were shunned for serious music reproduction, look at members systems if you don't believe me.
I agree with Stanwal. I believe you are trying for more bass than the speakers are capable of. Turn off the loudness and pull the EQ out of the chain. If you don't still have the AR sub consider a JL or Rel. Go for a 12" (or larger) driver in a sub from what I think you expect from your system.

That my opinion
I'm also using an Onkyo 7-band EQ and usually have the loudness activated on the Carver.

This may be your main problem - the loudness. Also I suspect the speakers you mention are roughly 4 ohm. This means your carver may be sending more than 40 to 60 watts - perhaps as much as 80 to 120 watts.

If you want to be able to play loud then look for a pro speaker like a Tannoy DMT 12 or something similar.
Thanks guys. I know this is rudimentary stuff, but that's where I am....learning the rudiments. Thanks for all the insight. One day in the not too distant future I'll have sufficient knowledge that I'll be able to appreciate something like the Tannoy's that Shadorne mentioned. Cutting my teeth on the more affordable stuff that is out there in abundance for now and establishing a reference as I slowly move into better equipment.
Speaking of ohm rating....the Paradigms are 8 ohm. Don't recall what the Polks are, but is an amp automatically able to drop to 4 ohm and double its output if it is hooked up to an 4 ohm speaker? I understand that the lower resistance enables the amp to double its power output, but not clear on the science behind this and the effect it has on the relationship between the power source and speaker. Can all amps go down to 4 ohm or does it have to be designed into it? Anybody care to give me a layman's explanation on this (as I'm not fluent in the electrical engineering vernacular).
An ideal transistor amp doubles its power every time you halve the impedance. Most are not ideal and may even deliver less power into lower impedance's. In some cases they will not drive them at all or damage them or itself. Weight is usually an indication of amp quality, the heavier the better.
Try running your system completely flat for awhile at about 80 dB SPL and let your ears readjust to the sound. You may just find that you discover distortion free music content with tighter bass content. Loudness controls add distortion by design.

Let us know.
What music are you playing and by what bands? Has the bass in the music been anded to? Is it on more than 1 piece of music? Are the speakers ported?
Wouldn't the "started to lose composure" be the early sign of the amp starting to clip;thats what I would suspect.
I agree with playing the system flat and removing the EQ as this elimates a electronic suspect and removes boost to certain frequencies.
Stevecham makes a great point. When I first got the audio bug, or better yet, the equipment bug, I had a Sony integrated amp at 110w a side driving Cerwin Vega D-5's at crazy volumes with the bass/treble turned up. I then upgraded to a Denon PRA-1500 pre amp and Sony TA-N 55ES power amp and used the tone bypass button. It took a little while for my ears to adjust to just how it was supposed to sound without all the added bass and treble I was adding, but once it did, I had a new appreciation for a flat output. Give it a try for a week or so. You will then be able to better hear differences among other pieces of gear!!