Thread: NuForce revisited, Reference 9.02

I managed to secure two Reference 9 amplifiers which had been updated to the latest revision 9.02 just recently. I still had the Reference 8s in my possession I decided to simply compare them directly in order to change if the Reference 9 is leap and limits above the Reference 8.

In starting I evaluated an Audio Precision measurement struture to measure the performance of the amplifiers. I started with a number of listening sessions comparing the Reference 8 to the Reference 9 and a number of other amplifiers.

The listening session gave that with the Reference 9 NuForce has at least changed upon the Reference 8; it is a nice amplifier, with good control, better imaging but above all a better verbal balance and clear In comparison to other amplifiers in about the same range it fails to impress it isn’t a showstopper, but a mediocre performer. One of the disadvantages is the small and narrow stereo image, something which was stated on with the Reference 8, and which is still there in the Reference 9. The Reference 9 was very good treated than the Reference 8 nevertheless.




For reasons not known NuForce has related to mount a 470nF capacitor transversely the speaker terminals. A typical common-mode filter consists of a common-mode coil with a capacitor mounted from each terminal to ground. A common connection coil with the capacitor mounted differentially is the similar as a common-mode coil with the maximum capacitor mounted on the input side, which doesn’t help to lower RFI because the problem with the NuForce amplifier is same.

In order to produce a less-pass filter with the common-mode coil it requires having a capacitor from each speaker terminal to the framework. I don’t have a range analyzer to amount this, but the overall feeling is that the RFI level of the Reference 9 can’t be more than 10dB lower.

It still shows a big price of ringing. That is getting rid of this ringing would improve RFI which is more than a half-baked common-mode filter. NuForce still hasn’t counted out how to contract with this matter is undistinguishable, because the answer is common knowledge