Can someone give me an explaination re: power amp.


So, I own a simaudio i-5 driving paradigm studio 60 v.3, and I am not happy with the sound at low volume. turn it up everything is great, but low volume has muffled sound. Everyone says the paradigms are efficient, but i go out looking for more efficient speakers, and happen to come home with a loaner power amp- a simaudio w-3 (125 wpc), and the sound at low volume sounds markedly better with the power amp. this is contrary to everything i have convinced myself to believe. i have convinced myself that a good integrated is all i need, but I cannot deny the sound. so instead of asking the age old separates vs. integrated question, i'm just going to ask- why does my system sound so much better at LOW volume with the power amp. Maybe the speakers aren't as efficient as I thought? Maybe the 70 wpc simaudio i-5 isn't as great a machine as i thought? maybe there's a technical explaination? Please enlighten me! and thanks, and merry christmas to all you audiophiles out there! (oh, and the reason I didn't come home with speakers is that i really love the full range of sound from the towers, and i couldn't find any highly efficient speaker that had the range I enjoy. not that it dosen't exist, but i just couldn't find it. I live in portland, oregon).
blazerfan
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okay. so it's an current/amps thing (at least in this particular situation). The thing is, I have a decent sized room, and i can handle full range speakers. for example, i listened to the ProAc Response 2.5 the other day, and I really really (i mean really) liked them. and regardless of where I go with this hobby, it's starting to look like a good high current amp is going to give me the flexibility to audition a wide(er) variety of speakers over the next few years. I think I can still get there with an integrated Kijanki, but starting to think a separate high quality amp is going to provide the most "room to move" over the next few years. I mean, lets face it, no matter what I tell myself, i'm going to be purchasing different items, micro-analyzing my system to death, for a long while- i just can't help it anymore. i give up. :)
Hi Blazerfan -
I have the same view that Bob Reynolds posted "regarding a high-current amp and its impact on low volume listening".
I do not see the connection either.

What Preamp were you driving the w-3 with??
Your Speakers do not seem to be a tough load requiring lots of power - Nominal impedance: 8 ohms. Sensitivity: 91dB/W/m (room), 88dB/W/m (anechoic).
Bob - I also cannot see connection between high current and low level performance. In each case (including my small class D amp) it is most likely related to particular amp design.

Blazerfan - My whole system consists of DAC with volume control and Power Amp plus very good interconnect in-between (Acoustic Zen Absolute). Music comes thru Airport Express or from DVD player (or HDTV). I listen very often at low levels at night(Duplex + wife asleep) and really like the sound.
I used my simaudio i-5 integrated as a pre. The sound and low volume was much clear and clean. background instruments and vocals were audible. My girlfriend and her 8 year old son both thought the w-3 sounded much better, and they are not very critical listeners.