ARC VT-200 Cooling Fan Noisy, nit picking?


I would be the last person to claim that I have the most sensitive hearing but in my well-damped dedicated listening room, the sound of the cooling fan in my amp is noticeable (and distracting at times). I've even set the adjustable speed to the slowest setting and I can still hear it. The amp sits on an amp stand between my speakers about 10' from my listening chair and has plenty of ventilation but anyone familiar with the VT-200 knows that it can put out some serious btu's. Would it significantly affect tube life if I disconnected the cooling fan? Anyone else try replacing the fan with one that runs more quietly? Is this an "Ask Leonard" question?
jc4659
I don't think you are nit picking. It is noise that is being generated that is interfering with your music listening - which is unacceptable. I don't know if you can do anything about it but there is a way to minimize fan noise and still move some air if you work around the problem from the original design. One way to do it is to use two 120 volt motors in series (electrically) so they only see 60 volts each and run at reduced speed and noise. The two fans move less air individually than normal but the combined output may be close (may be more or less) to the original single fan but with less noise. I built a custom amp that I only needed to move a small amount of air in so I used a single 220 volt fan and applied 120 volts to it so it moved enough air but was silent unless you got your ear close to the amp. Sorry there isn't an easy answer but you might contact ARC and see what they have to say.

Brad
Two fans will lower the speed of each, but then you'll have the noise of two fans beating the air(no benefit). Place a 560 ohm, 10 watt power resistor in series with the fan, and it will reduce the speed significantly. Personally- I would remove the top cover, and raise the amp slightly with isolation devices(like Isoclean Tip Toes or something similar/taller) to increase the air flow/convection, and let it ride. Ambient noise sucks the life out of music listening for me too. A slight shortening of tube life isn't much of a price to pay for increased listening pleasure(to me anyway- My mono blocks only have half the 6550s of your VT-200).
I have found the fans in all AR product noisy and are very distracting when listening to music specifically on quiet passages etc. You would think by now that ARC would realize this issue and correct, all they have to do is put in a better fans.

You can order quieter fans from other sources, check out other AR threads for info.
I agree with rodman. Remove the top cover and elevate the amp. This will improve cooling.
I saw a mod a while back for fans that we're much quieter. I wish I could remember where I read it. I believe it used some high quality computer fans but, I'm not certain. Do some googling and you may find it. I have a VT-200 and have mine closer than you, in the medium setting and have not found it too distracting. It may be that your fan has gone bad and a new unit from ARC may fix it but, that's just a guess. You might even wish to call Steve Huntley at GNSC. He's worked on these and may have a suggestion.

All the best,

Tim