Same watts at 8 and 4 ohms?


I'm in the market for an integrated amp and trying to sort through tech specs. My understanding of the tech aspects of hi-fi gear is limited. Looking for some clarity in regard to watts-per-channel specs.

It is my understanding that wpc at 4 ohms is typically 1.5x -2x the wpc at 8 ohms.

But I'm seeing a number of respectable mid-fi integrateds with the same wpc for both 8 and 4 ohms. The NAD 388 is one and I think this is true for several of the Cambridge Audio units at a similar price point ($1500-$2000).

The NAD features make a point of saying " 4-ohm stable for use with a wide range of speakers". 

Would appreciate any insight to what these specs mean and what 4 ohm stable really means to me. My speakers are 4 ohm speakers.

Thanks,

George
n80
Well, in my defense (as if speaker choice needs defending) I got both sets of my speakers for free and driven properly they both sound amazing to my far-from-golden ears. 
Baconboy you can take it for what it's  worth, I’ve read reviews of the NAD C388 driving maggies and other hard to drive speakers. I used the C388 with some Ohm Walsh 2000 and it handled them with ease. You should probably check some maggie threads and see what others use.
If you're ready to consider a serious setup - amp and not integrated - I would recommend the H2O Audio S250 Signature.

Old school linear power supply, dual big transformers, B&O Class-D. Puts out 250/500W into 8/4-ohms. Handles 1-ohm Apogee Scintillas with ease.

It will easily run any of your speakers. You can leave it on all day and it doesn't get warm. A solid piece of gear, I had it for a while with Scintillas and Duetta Signatures and it was a great match.

Read a review or two and check it out...
The Aerial speakers are not that hard to find an amp for, your criteria limits your choices but you should find something appropriate. If memory serves Crutchfield paid return shipping on a preamp I tried about a year and half ago. I hate doing returns but the with no B&M stores close I've resorted to it a couple of times.