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
@millercarbon, I get what you're saying but I have to narrow down the field somehow. And with a budget of under $2000 and no dealers conveniently close, auditioning is nearly impossible outside of shipping stuff back and forth which is time consuming and possibly expensive.


I can tell you that they sound great with a Classe' Sigma SST pre into a Bryston 9B (both are AV units). But those are not mine to keep and they are too bulky and 'ugly' for the room.
I  think the two you mentioned  either NAD C388 or Cambridge 851A would work with those speakers. The Bryston you mentioned is 140 at 8 Ohm and 200 at 4 Ohm if that drives them loud enough for you then the others would. If you use Crutchfield you get a pretty good trial time. 
Have you looked at the Rogue Sphinx v3?
Have you checked out Vincent integrated models?

90 is above average; 4 dropping to 3 is a bit below average.

Poorly engineered amps will be uncomfortable with that impedance.

If you deal with Crutchfield, Audio Advisor, Music Direct, and no doubt others, you'll have a generous audition period.


Thanks djones51. I should also mention that these will rarely if ever be used at high volumes and in fact I would put more of a premium on low volume listening in this room.
I have an NAD C316BEE down at my cabin and it sounds really good for the price. That Guttenberg guys says the 316 is his 'reference' budget amp for whatever that is worth.
Anyway, I guess it may just come down to trial and error, order and return but I do hope to narrow it down to two or three.
I don't think the Cambridge has a DAC, which I am looking for. The NAD does have a DAC.

I might start with the NAD. Also considering a Peachtree Audio Nova300 and remote possibility of a used Gato DIA 250. Some reservations about the Gato in that it is well over my preferred budget and I wonder about the possibility of service if needed.


I think that what Ralph is saying is that doubling power into 4 ohms is only necessary if you drive the amp to its full output. 

If your amp puts out 150 watts into 8 ohms and 200 into 4 ohms, it will drive your speakers just fine if you only need 100 watts into the 4 ohm frequencies to drive them as loud as you want to listen to them.

Is that right, @atmasphere ?

Playing your speakers (and most speakers) with 100 watts into 4 ohms would be really loud.  I think any of the amps you're looking at will drive your speakers satisfactorily.  So, as Ralph said, try to listen to the amps and pick the one that sounds the best to you.