Behringer EP series Fan Modifications

[kgveteran]

One guy over at AVS used a 5W pot and dialed up the resistance until it was as quiet as possible while still allowing the fan to start reliably when the amp was cold. I think the QSC/Behringer amps vary the fan voltage depending on temperature.

I think that was me .I wish i knew what value the potentiometer was, but that is what I did to all (4) of my QSC's.I just backed off the speed until the motor stalled then increased it until it would begin turning at all the start ups.Then gave it a little more juice to ensure operation.I have four 1450's at about 8' away and they can be heard, but not like before.

[bobgpsr]

Hey me too with my Mackie M1400 (24V dc Panaflow fan). I just kept trying different series/parallel resistor combos to get a value when the fan would reliably start when the amp was cold. The Mackie has variable speed fan drive. In my case it ended up at 130 ohms. I also added a switch to bypass the resistor for times when I decide to really push my Tumult sub :twisted:.

I think to compare the fan noise specs they use the A weight curve when spec'ing fans. I measured before and after with the RS SPL meter's C curve and saw a 10 dB SPL reduction with the resistor. 56 dB(C) with resistor, 66 dB(C) without when measured right at the front of the amp. The analog RS SPL meter is not sensitive enough to get a meaningful reading with the A curve.

Bob

[chasw98]

Hey me too with my Mackie M1400 (24V dc Panaflow fan). I just kept trying different series/parallel resistor combos to get a value when the fan would reliably start when the amp was cold. The Mackie has variable speed fan drive. In my case it ended up at 130 ohms. I also added a switch to bypass the resistor for times when I decide to really push my Tumult sub :twisted:.

I think to compare the fan noise specs they use the A weight curve when spec'ing fans. I measured before and after with the RS SPL meter's C curve and saw a 10 dB SPL reduction with the resistor. 56 dB(C) with resistor, 66 dB(C) without when measured right at the front of the amp. The analog RS SPL meter is not sensitive enough to get a meaningful reading with the A curve.

Bob

hey Bob:
Did you change the fan from what originally came with it?

Chuck

[bobgpsr]

hey Bob:
Did you change the fan from what originally came with it?

Chuck

The Mackie came with 1 Panaflow model FBA08A24H which is rated at 32 db(A). I considered replacing it with a FBL08A24L1A rated at 26 dB(A) and you can order it from Digikey --- but have not felt that I have to yet since the fan noise level now (with the 130 ohm resistor mod) does not bother me.

Bob

[SteveCallas]

I received a few of those connectors from Thomas and I picked up the 10 watt 100ohm resistors today, but I couldn't find any of the little two prong adapters that the connector plugs would fit in to. Could I just cut a paper clip into two small pieces and use that, then solder the wires on to the other ends?

[Dennis H]

Paper clips are steel. They would probably work but pieces of copper wire would be better.

[chasw98]

I received a few of those connectors from Thomas and I picked up the 10 watt 100ohm resistors today, but I couldn't find any of the little two prong adapters that the connector plugs would fit in to. Could I just cut a paper clip into two small pieces and use that, then solder the wires on to the other ends?

So you just got the female end, not the male end? If that is the case refer back to my post that comes with both male and female. Or try nosing around Radio Shack and maybe they have something that will work. I thought you only needed the female end but I guess you are making an extension, so to speak, that will hold the resistor and can be plugged in or out as wanted or needed.

[SteveCallas]

I thought you only needed the female end but I guess you are making an extension, so to speak, that will hold the resistor and can be plugged in or out as wanted or needed.

Yeah, I don't want anything permanent, I want to keep the fan mod discrete and able to be attached/detached. I was at Radio Shack and looked all over but wasn't successful in finding anything that would work.

Paper clips are steel. They would probably work but pieces of copper wire would be better.

I guess but I wanted something a little stiffer so there is less chance for it to come out. I guess I'll figure out something.

[SteveCallas]

Wired everything up with a 10 watt 100ohm resistor and no dice. On a hunch, I started testing with some of the small 1/4 watt resistors I had left over from a fundamentals of electricity course back at school. Sure enough, that 100ohm resistor was just too strong, it was blocking the signal. I guess with the Carvin using a variable speed fan, the signal isn't going to typically be very strong to begin with. Found that a 39ohm resistor did the job nicely.

With the spl meter an inch away from a front faceplate, the level won't even register. When I press the spl meter right up againt the front face plate of an amp, I get 51db from each. With the spl meter centralized inbetween the two amps, just about flush with the faceplates, the output won't even register. This is roughly a 4db decrease for each amp. I'm very happy - at my seat, about 8' away, with both running, it's as noticable as a mosquito coughing, even less than before with just one running, and that was barely noticable to begin with.

Thanks for the write up Chuck and thanks for the connectors Thomas ;x(

[JTR]

Dragging this topic out from history I wanted to present the modification I made to silence my EP2000 and EP4000 amps as an alternative.

Got Sunon KD2408PTS3 as replacement fans (26 dBA, 2200 rpm, 52 m3/H, 24V, 0,10A) but because I sit only 3m away from the amps I could still clearly hear them. Tested with simple batteries and found it would run in whispermode at 9V.
To get around that voltage I'd have to reduce voltage on the fan by 2/3rds, so I used one 2W 220 Ohm and one 2W 270 Ohm resistor, soldering each one on one lead.

This has really silenced the amps, very necessary as I use 6 for my open baffle active speakers.

[Jim Holtz]

Ryan:
Check out this link and see if it will work. The .1 spacing is a standard and the 10 inches of leads should be long enough to connect to any fan you choose.

http://www.allelectronics.com/cgi-bin/item/CON-242/189/2-PIN_CONNECTOR_W_HEADER,_.10%22

Let me know if it works.

Chuck

EDIT - After reading further, these connectors are meant to be used for cordless telephone batteries. If you have a cordless phone that uses a battery connector similar to this, take the fan & connector out and see if the plug will connect to your cordless phone. If it does, then this part will work.

Hi Guys,

Sorry to revive an old thread but I need one of these connectors. I am getting ready to perform a fan replacement on an EP4000 and would like to get the connector rather than snip it off of the original fan lead.

The link doesn't work and I don't know what the original lead looks like yet. (I haven't opened the case) Can anyone point to a different source for the proper connector?

Thanks!

Jim

[ThomasW]

2-PIN CONNECTOR W/HEADER, .10"

http://www.allelectronics.com/make-a-store/item/CON-242/2-PIN-CONNECTOR-W/HEADER-.10-/-/1.html

[Jim Holtz]

Thanks Thomas!

For some reason I couldn't get to that website by editing the old address. I appreciate your help with the correct link.

Jim

[chasw98]

Thanks Thomas!

For some reason I couldn't get to that website by editing the old address. I appreciate your help with the correct link.

Jim

Jim, isn't it nice to have a friendly neighborhood curmudgeon around to remember things when we can't?

[Jim Holtz]

Jim, isn't it nice to have a friendly neighborhood curmudgeon around to remember things when we can't?

Yes it is! Thomas takes excellent care of things.

Personally, I'm blaming it on "oldheimers". :rofl:

I'm glad I have you young whipper snappers around to keep the old man on track.

Jim

[penngray]

Thanks, :T I'm just chilling..... on a Sunday afternoon with nothing else to do. I am also going to put together a high pass filter page shortly.

Im very interested in that, thanks!

[penngray]

Jim, isn't it nice to have a friendly neighborhood curmudgeon around to remember things when we can't?

Chasw98, not sure if you are doing any more amp tests but some members over on AVS where curious if you would at some point again?

[Amphiprion]

You guys might also want to check out 5W zener diodes if you are looking for a good way to drop the voltage reliably regardless of what fan you have hooked up (and how power hungry it may be). Digikey has lots of them ranging from 33 cents to $1.50 USD. Here's an example:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=1N5346BGOS-ND

[joe_B]

What replacement fans are you guys useing?

[PeterV]

........anyone know what size cooling fan is in the qsc usa 1310?
want to replace mine with a quieter fan.
.....i already did the digikey replacement fan for my behringer ep amp,
and it worked great....nice and quiet
thanks
peterv

[mischmat]

Looks like a standard 80mm computer fan. There are alot out there that have low db with hight cfm/pressure for cooling. Look for CPU fans of that size they usually have higher pressure rating on them.

[PeterV]

Looks like a standard 80mm computer fan. There are alot out there that have low db with hight cfm/pressure for cooling. Look for CPU fans of that size they usually have higher pressure rating on them.

....would this fan be a drop in replacement for the one i would be taking
out of the qsc usa 1310? it is the fan i purchased for the behringer ep
amp that was suggested on this forum post.....

Panaflo FBA08A24L1A, 24V, 80x25.5, 21dB
Digikey P/N P9739-ND

thanks
peterv

[mischmat]

Yep, that's just a standard 80mm computer fan. You may have to change the ends to plug into the board but that's just a simple soldering job. This particular fan here http://www.ncix.com/products/index.p...facture=Noctua Has always had a high rating for being quiet and flowing a fair amount of air.

[PeterV]

Yep, that's just a standard 80mm computer fan. You may have to change the ends to plug into the board but that's just a simple soldering job. This particular fan here http://www.ncix.com/products/index.p...facture=Noctua Has always had a high rating for being quiet and flowing a fair amount of air.

......just checked out the fan

..thanks

peterv

[---k---]

I don't know about the QSC. But, it should be noted that the Behringer amps use a 24V fan. I believe that most computers use a 12V fan. Not saying that they won't work, but they might not work as exactly expected.

[frascati]

If you want to get a bit esoteric (hell, why not?) here's another fun approach.

...from one of my favorite sites to haunt

https://www.surpluscenter.com/item.asp?item=16-1361&catname=electric

Get enough extra hose length from Menards to locate the fan and radiator in the basement and plumb the hose through the floor where your cable tv connection is going through already. Put the cpu cooler on the heatsink. Wire the fan and pump (included) to a switched outlet on the amplifier through a 12vdc "wall wart" transformer. Pump and fan combined are less than .5 amp. Easy for just about any old wallwart.

Or just use any handy pump you've got on hand and plumb it into a sealed five gallon bucket of water in the basement. Five gallons of water is waaaay more than enough mass to dissipate any amp's heat, no fan needed. Less complicated, but you'd be hard put to find a copper cpu cooling block for less than the 39 dollar price of that entire kit above. You could 'roll your own' with coiled copper tubing and thermal epoxy harnessed to the heatsink. (we already did say 'void the warranty' here?)

OR simply cut a three inch hole in the floor behind the system (while the spouse is out shopping?) and run plastic dryer hose


down to the fan that used to be in the amp. What fun!
(for that matter, just put the damn amp on a basement wall shelf just below the system and extend its connections - it's remotely operated anyway no?)

Here's a gadget for ultra quiet cooling of theater lighting.

http://www.nuventix.com/files/uploaded_files/pf_SynJet%20PAR20%20LED%20Cooler%20Design%20Guide%20v1%200.pdf

But it could probably be shoehorned into an amp.

Perhaps I need to switch to decaf.

[Ryan_M]

Or just use any handy pump you've got on hand and plumb it into a sealed five gallon bucket of water in the basement. Five gallons of water is waaaay more than enough mass to dissipate any amp's heat, no fan needed.

The mass will have nothing to do with dissipating heat, it'll just take longer to heat up.

[frascati]

The mass will have nothing to do with dissipating heat, it'll just take longer to heat up.

Ok
A five gallon pail of water provides sufficent mass to absorb the heat your amp is likely to produce during the time you are powering it... and sufficent area to dissipate that heat in the time that you are not, unless you're using it 24/7 and have decided to enclose the bucket, for whatever reason, in a 16inch jacket of insulation.

Man, this really is a tough crowd.

[mischmat]

I don't know about the QSC. But, it should be noted that the Behringer amps use a 24V fan. I believe that most computers use a 12V fan. Not saying that they won't work, but they might not work as exactly expected.

I missed the part about it being 24v. I don't think that computer fans are rated to voltages above 14v. I know they undervolt well but have a feeling that over volting will result in a short life span of the fan.