Nuforce STA200 issue. Rumble every couple minutes


I just picked up a used NuForce STA200. 

I have it connected to a low gain tube amp, ~6db

If I let it sit there with no music (same with music) it will cause a major 'rumble' and the speaker driver is pulsating like crazy for a couple seconds. 

This happens every couple minutes. 

Any ideas?

128x128kray

Yes, I agree it has a great sound. It is that the sensitivity and gain make it not a universal pairing. Likely why it became so highly discounted. Maybe a good fit for a vinyl system with lower output cartridge and phonostage.

I am using mine with a 

’volume control on a box’ preamp driven by a 2V output DAC. 

The STA200 is an incredible amp, given the " proper system " it is paired with, and of course, the $499 selling price. People are giving them away it seems. 

Yes, people are giving them away because the amp doesn't serve their system. I have been thinking of selling mine. 

Another possibility would be to pair it with a DAC with an analog volume control. 

Another issue is that it isn't meant for speakers that represent a difficult load to a speaker, providing the same power at 8ohms or 4 ohms( 80wpc). 

 

do you guys know of a amp with similar sound characteristics to the STA200 with much lower gain?

@kray, it was designed to work with a passive preamp. @Mesch, it is not the perfect amplifier ( point me in the direction of " the one ", please ). Knowing it’s limitations, I bought my 1st one, and based on how much I enjoyed it, I quickly sold off locally, several other amplifiers I had in my large amp collection ( Mc 2105, Son of Ampzilla, Bedini 150, Hafler 200, B&K ST202, and a few others that I enjoyed,  and had good reputations. These were all up to spec, and they all had upgraded, heavier gauge power cables hotwired into them ( not a joke, when I tell you they improved greatly from this tweak alone ). I bought 2 more, to vertically biamp a pair of Signet SL280ex....an awesome system. I still have the speakers, but sold the two of the STA200’s, because I was down to one system ( with my Lascalas ), and felt someone else should enjoy them. I will keep my original STA200, as it takes up no room, and for what it does, it is a keeper. My best, Always, MrD. Enjoy !