SpeakerTalk

[skyhawk]

Hello everyone. Question, would the Audio Research VSI60 integrated amp be a good choice to match up with the KEF 104ab speakers?
2nd question, does the VSI60 amp have a passive pre-amp inside it?
Thanks to all who respond.

[TL 200]

[skyhawk]

I see. So the VSI60 has a passive preamp. What would be the result of using it with the KEF ab speakers? I don't understand why a passive preamp would not be a good match for the KEFs.

[audiolabtower]

There is no reason a passive preamp should not be ok. It is basically just a potentiometer on the input of the power amp, as long as the amp has sufficient sensitivity for whatever inputs you use the speakers can be driven to capacity. In the vs160 is appears to be relay controlled resistor ladder? The 50 watts is rated at 1.5% distortion which means that the usual way of defining power at 0.1% distortion is going to be somewhat less power. Purely my personal opinion I would like nearer a 100W amp with the 104s for transients since they are probably one of the most inefficient speakers Kef made. However valve amps are forgiving of clipping and depending on the size of your room and the loudness required it might be fine. But the vs160 talks about low impedance drive, the 104 is more like 10 ohms minimum across the power hungry bass and midrange, whether it has the voltage drive to run the 104s to capacity might be debatable?

[skyhawk]

Thanks for the reply. I had been considering the Jolida 302CRC integrated amp. Then I saw and read about the VSI 60 amp. I really want a tube amp. Any thoughts on the Jolida amp? I really don't want to buy something used unless I really know the history of the component. Any suggestions?

[iso]

Vsi60 specs specify 7dB or was it 7,5dB overal feedback... so outputimpedance would be something like 1,5-2,5 ohm from 8 ohm tap. Audiolabtower might have better undestanding how much 104aB do have impedanse variation... but I suppose that this is not ideal situation.

ARC Classics and CJ Premier 11 do have outputimpedances at around 0,5ohm, so speaker load caracteristics are not too important consideration with them. But they do need proper preamp for good performance.

Audiolabtowers note about unbuffered pot in integrated amp like VSI60 is correct. Situation is bit different when using poweramps due inteconnects and maybe for other reasons too.

Best Regards

Kimmo

[audiolabtower]