NuForce vs Bel Canto

I see you have a tube pre-amp.

Bel Canto mk II or m ref series are the BC products to look at for best results with a tube pre-amp. These have a 100Kohm+ custom input stages designed for best results with a tube pre-amp.

The Nuforce site indicates only 22Kohm input impedance for that model, which is a less optimal match for most tube pre-amps, at least on paper.

I can vouch for the sound quality of the BC ref1000m mono blocks I use. I went with this specific BC model in that my system benefits from more costly BC tweaks to stock IcePower Class D amps (these tweaks are not present in less expensive non ref series BC Class D amps) in their latest and greatest mkii or m ref series amps.

These are an improved power supply internally which helps with larger or more power and current hungry speaker designs and the custom higher impedance input stage for optimal results with tube pre-amps.

The beter Spectron amps are the other Class D amps that I considered with similar features that would be another option to BC ref mkii/m series amps. I have not heard these so I cannot comment though I would expect their performance to be similarly good.

Rowland makes otehr highly regarded Class D amps that I am less familiar with.

Thanks for the info Chuck!

Wyred4Sound is another good but less expensive Class D option designed for good results using tube pre-amps.

Thanks Mapman. I recall your happiness with the BC's from a comment in my virtual system. The Kora Crescendo preamp really seems to 'play nice' with everything I have tried it with so far.

I will no doubt keep the input impedance in mind as I come closer to a decision.

Regards,
Chad

Claud,

I would not expect a less than optimal match to sound bad. Some might even prefer the sound.

Generally a higher amp input impedance can help assure lower distortion and better dynamics, especially with tube pre-amps which tend towards higher output impedance by nature, some more than others. It can also vary by frequency in a manner taht is not reflected in published impedance specs. So its a matter of degree more so than good/bad perhaps. Also its more of an insurance policy to hedge your bet towards better results in that exact results cannot be known in advance or in lieu of an apples/apples a/b comparison.