SVT 3 Pro Fan Noise

slloyd0915 · #1 10-16-2011, 04:49 PM

I've had this head since I turned 18, about 7 years ago. I've never had any problems with it in that time. A week or so ago it started making noises like it was going to take off from my cabinet. I felt the all around the sides of the head to see if it was hot and nothing felt out of the ordinary. The fan has been running all the time tho. I've looked online at different things and I'm not too sure if I should have the fan replaced or what. Any help would be appreciated. Thanks.

RickenBoogie · #2 10-16-2011, 05:25 PM

If it's not keeping the amp cool, replace it. Otherwise, I wouldn't worry too much. Should be an easy enough job, but it's always best to have it serviced by a qualified tech- so you know everything is alright.

**B-string** · #3 10-16-2011, 05:27 PM

Yes replace it now before it fails. Johnk_10 or Jerrold Tiers can supply good links for replacements.

mophead · #4 10-16-2011, 08:15 PM

You can order them from DigiKey.

Jerrold Tiers · #5 10-16-2011, 08:34 PM

Hold on there.............

is the fan acting normally, but making noise?

Or is the fan going at full speed all the time?

#1 is a fan problem, #2 is a fan DRIVE CIRCUIT problem...... inside.

**B-string** · #6 10-16-2011, 09:22 PM

Quote:

Originally Posted by Jerrold Tiers

Hold on there.............

is the fan acting normally, but making noise?

Or is the fan going at full speed all the time?

#1 is a fan problem, #2 is a fan DRIVE CIRCUIT problem...... inside.

Good catch!

beans-on-toast · #7 10-16-2011, 09:34 PM

If the fan is acting normally but making noise, sometimes a good cleaning can help.

If your amp hasn't been serviced in seven years, it is possible that there is a buildup of dust inside the amp and on the fan blades. Having a tech clean it can help the components dissipate the heat better. If they can't dissipate the heat, the fan is going to work harder to cool the amp.

will33 · #8 10-16-2011, 09:51 PM

Quote:

Originally Posted by beans-on-toast

If the fan is acting normally but making noise, sometimes a good cleaning can help.

If your amp hasn't been serviced in seven years, it is possible that there is a buildup of dust inside the amp and on the fan blades. Having a tech clean it can help the components dissipate the heat better. If they can't dissipate the heat, the fan is going to work harder to cool the amp.

+1 to trying giving things a good cleaning before buying stuff. If it's still noisy after cleaning it, the bearings could be on their way out and it probably should be replaced, that would be your "plane taking off" sound. If it's of normal noise after cleaning but just runs all the time, the actual fan is ok but some temp. sensor or something went bad.

BagelBruin · #9 10-16-2011, 10:03 PM

My 4 Pro makes the exact same noise. It does it after being on for about 60 seconds.

I think is sounds like a tiny high pitch bomb being dropped, but a take off sound makes sense too.

slloyd0915 · #10 10-19-2011, 03:14 PM

Thanks a lot guys. I appreciate the help. The fan is running full speed all the time. I took the top cover off just to look at it and it was quite dirty. I'm gonna go and have it cleaned thoroughly and see if that fixes the problem. Again, thanks for all the help.

Jerrold Tiers · #11 10-19-2011, 09:24 PM

The fan circuit has a problem.

it is temperature-variable, and when first turned on, it should run slow (might be fast for just a short time). As the amp heats up, it should speed up.

If yours is fast all the time, the fan is probably fine, but the circuit is not working right.

The fan circuit is part of the heater circuit for the power amp tubes. It needs to be working right, or the fan and/or tube heaters may suffer. Shouldn't be anything huge, most likely a bad solder joint. let a tech see it