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Conrad Johnson ART amps - Watts at 8 ohms vs 4 ohms

I had always thought of the ART150 and ART300 as being a 150 watt and 300 watt amp, respectively. Recently I noticed that on their website they are in fact rated as 150 watts into 4 ohms, and 300 watts in to 4 ohms. I've read that in many cases what puts out 200 watts at 8 ohms, for example, will put out 400 watts at 4 ohms, 800 watts at 2 ohms, 100 watts at 16 ohms, etc.
In this case, it would mean the ART150 generates 75 watts into 8 ohms (150 into 4), which does not sound right.
Can anyone shed some light on what these amps put out at 8 ohms? Would be appreciated. Plan on asking CJ directly as well and will certainly report back what they say, if it's of interest to anyone.

https://conradjohnson.com/art150-and-art300-amplifiers/

150 Watts rms per channel from 30 Hz to 15 KHz at no more than 1.5 % THD into 4 ohms (also available connected for 16 ohm loads)

300 Watts rms from 30 Hz to 15 KHz at no more than 1.5 % THD into 4 ohms (also available connected for 16 ohm loads)
gmercer
gmercer OP
193 posts
 
For everyone's benefit here are some specifications for the ART-150:
Power output into 4 ohms is 150 watts. Power output into 8 ohm is 101 watts.

With the above information, which comes from CJ, I would suggest that the ART300s (which put 300 watts into 4) will put about 200 into 8 ohms.
batman1971
96 posts
 
Not sure how they are getting those power ratings with only 2  kt 150 per channel   Seems dreamy.   
gmercer OP
193 posts
 
@batman1971 I've heard before that CJ extracts every ounce out of the tubes in a way that no one else does. I listened to the amps a couple times before and I do not doubt the 100wpc rating based on those experiences.
The VAC Signature 200iQ puts out 100wpc with 4 tubes as well, 2 per channel, and that is using KT88s (versus the KT150s found in the CJs).
My dream amp would be a 200 wpc stereoblock from CJ, wish they would.
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