Menu Close

SVT Fan Repair/ Replacement

Home Forums Tech Forum SVT Fan Repair/ Replacement

Viewing 3 posts - 1 through 3 (of 3 total)
  • Author
  • #149833
    Been thanked: 49055 times

    I adore my Ampeg Heritage SVT. However, there is one thing that I hate about it… and it’s not the fact that it weighs 100 lbs.

    It’s the loud ass cooling fan!

    Trivial to most… After all, even at low volume, you can’t hear a noisy cooling fan once an SVT is rocking, but the sctmmc is all about principals, and the flagship model of the bass amp, which is touted as the ruler of the low-end universe, shouldn’t have an embarrassing fan.

    How loud are they? Exactly loud enough to draw the attention of everyone on stage during warm up. So look at it like a flat tire, yeah you can drive on it, but you’re fully aware that something is wrong, which if ignored, usually leads to more expensive repairs in the mechanical world.

    I called Ampeg and I got a human on the phone! So I could’ve died happy, but I was a little taken back when the rep knew the part number off the top of his head. Plus, I’ve bought a few fans in my time, and $40 sounded three times too expensive.

    Not that $40 to fix it was too expensive for the repair, but considering that this American made gem had already failed prematurely, replacing the broken part with the same crummy part didn’t make much sense. And, knowing what I know about manufacturing short-cuts, I just had to quest for a better way.

    The Heritage is the American version of the classic
    These pics are just for ref… You’re not going in the back! TWSS
    All you need to do is to remove the four giant silver screws on top of the cabinet
    Once those top screws are removed, slide out the control panel, which will allow you to pop the grill cloth panel free from its “industrial grip Velcro”, and then unplug the fan.
    Now you should have this in your hand… Unscrew the four black screws, which are holding in the fan, and hmmm.. What are we looking at?
    Strategic manufacturing is what you’re looking at. Ampeg doesn’t want you to know what fan is in your amp, and it’s cheaper to hide the specs with a black sticker, than it is to pay an American to remove the product label.
    The oem fan is a 115 volt, impedance protected, 2300 rpm unit.

    One of the most costly manufacturing differences in electric motor construction, is ball bearings vs. bushings. Whether its a vacuum cleaner, a jack hammer, or a cooling fan… It has an electric motor, and it either has bushings or ball bearings.

    Ball bearings are precision manufactured from stainless steel in Switzerland or Germany, and bushings are made from crap by a guy who rents his shop from the Tuscan Raiders.

    So what came in the Ampeg? Cheap bushings of course.

    But when I searched for a replacement fan of suitable specs, I discovered a part number variation. Sunon, the OEM fan manufacturer had two fans with these specs… an HSL and an HBL. HSL “Sleeve”, and HBL “Bearing”.

    A trip to Amazon, and I get the OEM fan, with the upgraded Stainless, German Ball Bearings, for $17

    So, now I still have the OEM fan, for less than half of what Ampeg would’ve charged me (for a fan that they should’ve just given me), and it’s upgraded with the BB’s, so it’ll last thousands of hours longer than the cheap bushing unit. Now this amp is finally on it’s way toward “earning” it’s reputation…

    I will say that there are differences between the decibels of a bushing fan vs a bearing fan, and yes, the bearing are louder… However, the difference is inaudible, and far below standard recording studio noise requirements.


    First, whack the driver, then, off the passengers. I want everyone in the car whacked off.
    ... Al Capone

    Jeff Preston
    Been thanked: 4144 times


    G&L USA JB, FrankenJazzuar, Hartke 210 Combo, Darkglass B7K Ultra, Boss GT-1B, EBS Fuzzmo, Mod Tone Deep Dive Octave Plus.

    1 user thanked author for this post.
    Jim C
    Been thanked: 1228 times

    My SVT-CL is on the bench waiting for NOS 12AU7’s to arrive.

    Is there a fan that’s quieter than stock regardless of bearing type?

    1 user thanked author for this post.
Viewing 3 posts - 1 through 3 (of 3 total)
  • You must be logged in to reply to this topic.

For New Registrations, "Contact Us" and Tell us Your Favorite Movie.