[Gradofan2]

Quote:

Originally Posted by Ferbose /img/forum/go_quote.gif You misunderstood. 30W into 8 ohms requires 15V voltage swing. But you never know if your speaker amp can deliver 15V voltage swing into a 120 ohm load (actually K1000's impedance goes to something like 300 ohms). On the other hand, Cayin HA-1A can reliably deliver >1W into a 120 ohm load or even a 300 ohm load, which is exactly what K1000 needs. K1000 can be driven by both speaker posts and headphone jack on HA-1A--they sound different. I like to the headphone jack these days.

Perhaps... I missunderstood you... but... I didn't missunderstand the AKG tech - who stated simply, "a speaker amp with 30 watts per channel into 8 ohms is the minimum required to drive the K1000s."

Now... if 1-2 watts per channel into 120-300 ohms is equivalent to 30 watts / channel into 8 ohms - then fine... but... if not...

 

[Ferbose]

If you read K1000 manual, it needs at the minimum 0.4 W into 120 ohms of load (to reach 100 dB SPL), which is 7V of output voltage swing. To provide even more headroom, 14V should be plenty. 14V into 8 ohms load equals 25W, and that is why the AKG tech says it should be a speaker amp of 25W. 14V into 120 ohms is 1.6 W. Due to distortion characteristics, 1W of tube amp will play as loud as 2W of solid state amp. A tube amp capable of 1W into 120ohms is exactly what you need for AKG K1000, and HA-1A does just that.

It is all just ohms law: Power=Voltage^2/Resistance