Hartke KB12: fan is too loud

fretlessman71

fretlessman71

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#1
Sounds stupid, huh? "Just turn up the volume and you'll never hear it". Very true.

But recently I've been performing with some quieter ensembles (choirs, orchestras) where the fan is rather noticeable in very quiet sections of the music.

I'm sure this has been talked about, but searching for "loud fan" gets me the wrong kind of loud, and the wrong kind of fan.

Have you replaced the fan in your Hartke KB12 or KB15? Was it easy? Did it help?
 
#2
Same issue on my previous KB15, just annoying me when bedroom practice.
I been email Samson customer service team in early day, but seem they din't make any improvement on fan noise issue at all.

But the noise level still lower than Ampeg Micro SVT.
 
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#3
I have a KB12 and I replaced the fan.
It was very easy, almost plug n' play, but is difficult to find a better fan because the one that it uses is a 60x60x10mm, 12v and 2 pin fan and there isn't much to choose from.
The change did make the amp emit less fan noise? yes, but it wasn't a dramatic improvement.
The total cost of the operation was 9€, so it's worth the try...but I am sure that in the USA there will be more to choose from and of better quality.
At the end of the day for me it is worth because the amp deserves it, it sounds fantastic and is so powerful, a total sleeper on the combo section.
 
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#4
Sauron_ said:
I have a KB12 and I replaced the fan.
It was very easy, almost plug n' play, but is difficult to find a better fan because the one that it uses is a 60x60x10mm, 12v and 2 pin fan and there isn't much to choose from.
The change did make the amp emit less fan noise? yes, but it wasn't a dramatic improvement.
The total cost of the operation was 9€, so it's worth the try...but I am sure that in the USA there will be more to choose from and of better quality.
At the end of the day for me it is worth because the amp deserves it, it sounds fantastic and is so powerful, a total sleeper on the combo section.
Click to expand...
So where does someone who's never worked on his own amp find/search for such a fan? Electronics stores? Would you mind sharing the make and model of the fan you bought so I can start a Google search and have half an idea of what to look for and where?
 
#5
That's a common issue with any fan equiped amp.It has to do with the bearings inside, just remove the plastic cap at the center and gently pour some synthetic oil like you would for any car engine, it greatly helps reducing the annoying sound it can make, I've had the same issue with my old trusty Markbass LMII built in 2007, same fan since 2007! I just do the synth oil job once every 6 months when it starts to be a lil' bit "loud".
 
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#6
My LX8500 also has the loud fan issue. It's not actually an issue for me but I can see the sound maybe getting picked up by a sensitive mic live during quiet bits and see why that bugs people
 
#7
Sauron_ said:
I have a KB12 and I replaced the fan.
It was very easy, almost plug n' play, but is difficult to find a better fan because the one that it uses is a 60x60x10mm, 12v and 2 pin fan and there isn't much to choose from.
The change did make the amp emit less fan noise? yes, but it wasn't a dramatic improvement.
The total cost of the operation was 9€, so it's worth the try...but I am sure that in the USA there will be more to choose from and of better quality.
At the end of the day for me it is worth because the amp deserves it, it sounds fantastic and is so powerful, a total sleeper on the combo section.
Click to expand...

fretlessman71 said:
So where does someone who's never worked on his own amp find/search for such a fan? Electronics stores? Would you mind sharing the make and model of the fan you bought so I can start a Google search and have half an idea of what to look for and where?
Click to expand...

How about Aliexpress ?

https://www.aliexpress.com/item/1005004205974469.html?spm=a2g0o.productlist.main.1.56da77ff0Vgo1n&algo_pvid=e852742a-29e3-4765-b5ff-f1fdcb0d7d15&algo_exp_id=e852742a-29e3-4765-b5ff-f1fdcb0d7d15-0&pdp_npi=3@dis!MYR!8.4!7.45!!!!!@212279a216867382617467038d07dc!12000028381916842!sea!MY!1801748259&curPageLogUid=zgodWUReCxdn

https://www.aliexpress.com/w/wholes...+computer+fan&spm=a2g0o.productlist.1000002.0
 
#12
https://www.digikey.com/?utm_adgrou...MIm-zyjZnD_wIViavICh37jwNqEAAYASAAEgIGHfD_BwE

Look here for a good replacement. I've changed cooling fans on several amps with excellent results.
Try to find the specs of the original by part number lookup and then find a same sized fan with a lower db rating with a higher or equal cfm rating.
Sometimes if there is room you can go with a slightly thicker fan, this gives more options available. Sleeve bearing fans are typically quieter than ball bearing fans. Also the RPM rating has alot to do with the sound as well but rpm also affects cfm rating.
Of course you need to keep the same voltage rating and the same current draw or lower rating.
 
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#13
Sauron_ said:
I have a KB12 and I replaced the fan.
It was very easy, almost plug n' play, but is difficult to find a better fan because the one that it uses is a 60x60x10mm, 12v and 2 pin fan and there isn't much to choose from.
The change did make the amp emit less fan noise? yes, but it wasn't a dramatic improvement.
The total cost of the operation was 9€, so it's worth the try...but I am sure that in the USA there will be more to choose from and of better quality.
At the end of the day for me it is worth because the amp deserves it, it sounds fantastic and is so powerful, a total sleeper on the combo section.
Click to expand...
Would a "fatter" fan have fit? 60x60x25, for example?
 
#14
I’ve always pondered why no one ever uses centrifugal fans in hot amps. They are much more efficient and quieter than axial fans. The only reason I can think of is they are more expensive and take up more room.

upload_2023-6-14_12-51-45.gif
 
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#15
Be sure you understand what you are doing, or you may end up with a bigger issue.

Replacing a fan seems easy, but the designer of the amp chose that fan based on CFM at a specific static pressure. There are different ways to do this, but you need to respect the voltage, current, CFM, static pressure and it must fit.

Don’t go pouring oil in the fan, or buy fans that do not have an IEC-60065 safety rating (which the original part has). Non-rated parts can be a safety/fire hazard under stalled conditions.
 
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#16
PrinceByTor said:
I’ve always pondered why no one ever uses centrifugal fans in hot amps. They are much more efficient and quieter than axial fans. The only reason I can think of is they are more expensive and take up more room.
Click to expand...
I suspect space has an awful lot to do with it, yes. Probably don't take well to getting bounced around either, which is something that regularly happens to amps.
 
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#18
fretlessman71 said:
Sounds stupid, huh? "Just turn up the volume and you'll never hear it". Very true.

But recently I've been performing with some quieter ensembles (choirs, orchestras) where the fan is rather noticeable in very quiet sections of the music.

I'm sure this has been talked about, but searching for "loud fan" gets me the wrong kind of loud, and the wrong kind of fan.

Have you replaced the fan in your Hartke KB12 or KB15? Was it easy? Did it help?
Click to expand...

Close friend of mine has a couple of these atm, and all he complains about is the fan noise from that combo!
 
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#19
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