Behringer EP series Fan Modifications

[chasw98]

I had said I would post some pictures as to how I modified my Behringer amplifiers for quieter running fans, but I do not want to hijack the OP thread, so I started a new one. Here is the link to my instructions.

http://www.cwitt.com/epfanmodification/index.html

Chuck

[ThomasW]

Cool.....pun intended ....

Thanks for creating the website... :T

[chasw98]

Cool.....pun intended ....

Thanks for creating the website... :T

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.

[steve nn]

Nice job Chuck. How much of a edge would you say it took off the fan noise?

[chasw98]

I do not know for sure. When I had the fan out of the case, I A-B'ed it with and without the resistor and it is a significant decrease. On Tuesday, my other EP2500 arrives and I was going to do some SPL measurements before I mod it and after I mod it. I had already put both back together when I thought "I wonder how much reduction in noise this accomplished?". Doh :roll: I wil take measurements on Tuesday when I get the new one and compare it to the modded one with the fan in place in the amp and post them then.

[steve nn]

On Tuesday, my other EP2500 arrives and I was going to do some SPL measurements before I mod it and after I mod it.

Great! I'll be very interested in your findings. If I ever decide to go NF placement like I did with my QSC along time ago, it would be a big help. Come to think of it, considering the cost of the EP...it might be worth doing anyway.

[dyazdani]

Nice job. I just bought a EP2500 for my DIY sub. If I ever get the thing built, I'll see if I need the same mod.

[chasw98]

OK, I got my 2nd EP2500 today and I took measurements. They are very rudimentary and unscientific but for comparison, they will do. All measurements were taken 1 inch away from the openings in the front and rear of the amplifier with c weighting and slow response.

Ambient SPL in Garage - 55 db
Stock Fan Rear - 75 db
Stock Fan Front - 72 db
Modded Fan Rear - 69 db
Modded Fan Front - 67 db
Modded Reversed Fan Rear - 72
Modded Reversed Fan Front - 69

This was done using a 100 ohm resistor. If I had had a decade box or an assortment of resistors, I probably could have found the sweet spot of fan speed versus SPL. I have reversed all my fans because I don't like the idea of blowing debris inside the amp over time as opposed to gaining some lower SPL that I don't find objectionable right now. Remember these were taken at 1 inch away, so the loss by sitting 8 - 10 feet away makes them inaudible to me right now.

[Dennis H]

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.

[HMenke]

Would it be possible to use a thermistor with a negative temperature coefficient? High resistance at ambient room but as it warms up the reistance drops.

[Dennis H]

The amp (QSC/Behringer) already does that. You just want to slow the fan at all temps so a fixed resistor is fine.

[HMenke]

Won't that risk damaging the amp?

[PMazz]

While I've got my gear torn apart I was thinking of doing this to my Carver amp. I had remembered this site I bookmarked a while back, if it helps anyone.

http://www.cpemma.co.uk/diodes.html

Pete

[chasw98]

Cool page. Lots of good stuff. Thanks.

[Ray_D]

All

Wouldn't it be easier to just put in a quiet fan, like Panaflow? That's what I do with my computers.

Ray

[PMazz]

All

Wouldn't it be easier to just put in a quiet fan, like Panaflow? That's what I do with my computers.

Ray

Well, I tried the resistor trick and it helped but a noisy fan is a noisy fan. I ordered a Panaflo and installed it. I needed a 24V fan for the Carver and I could only find one at Digikey. Now the amp is absolutely silent unless you put your ear on the enclosure. Best $18 I've ever spent.

Pete

[chasw98]

Neat! Quiet amplifier. Does it seem to move enough air to exhaust the hot air out of the amp (or blow cool air in?)?

[Jose_L]

Which panaflow did you use ? The H(High), M(Mid), or L(low) version ? Also which size ? 80mm ?


Regards,
Jose

[ssabripo]

hey old man...how about tossing one of those EP's my way! or better yet, that nasty BFD you got there; it doesn't even match with the rest of your system

nice job as always Chuck

[chasw98]

hey old man...how about tossing one of those EP's my way! or better yet, that nasty BFD you got there; it doesn't even match with the rest of your system

nice job as always Chuck

Trust me, I'll be takin' that broken Krell out of your house this weekend and when I make it work, we'll talk! BOY!

[ssabripo]

Trust me, I'll be takin' that broken Krell out of your house this weekend and when I make it work, we'll talk! BOY!

ha, I wish I could say is all yours, but you may wanna follow up with the lucky craiglister who just bought it this past weekend :B :T . Got some money back, which is better than using it as a door stop :P

[PMazz]

Which panaflow did you use ? The H(High), M(Mid), or L(low) version ? Also which size ? 80mm ?


Regards,
Jose

Spec Sheet

It's the FBA12G24L1A, 120mm x 38mm, 30Db-A. The amp seems cool enough. It's got a variable fan control built in. It runs at 12V initially and, according to the PCB printing, goes up to 15V. Besides, HT and music is mostly cruising for pro amps. I'm keeping an eye on it tho, as I run it with a 2ohm load.

Pete

[chasw98]

ha, I wish I could say is all yours, but you may wanna follow up with the lucky craiglister who just bought it this past weekend :B :T . Got some money back, which is better than using it as a door stop :P

YOU SOLD IT! AND YOU DIDN'T ASK ME FIRST?

[ThomasW]

YOU SOLD IT! AND YOU DIDN'T ASK ME FIRST?

Ah oh, someone's in trouble... 8O

[---k---]

I knew that marriage was doomed from the start!

[Dennis H]

Here's the digikey part recommended for the QSC (and Behringer) amps by the QSC sales rep.

Panaflo FBA08A24L1A, 24V, 80x25.5, 21dB
Digikey P/N P9739-ND, $8.25

[chasw98]

I knew that marriage was doomed from the start!

I have a headache tonight :Z honey!

[ssabripo]

YOU SOLD IT! AND YOU DIDN'T ASK ME FIRST?

but honey...you didn't ask me! I didn't know you wanted it ops:

:rofl:

[chasw98]

I'm speechless

[---k---]

Here's the digikey part recommended for the QSC (and Behringer) amps by the QSC sales rep.

Panaflo FBA08A24L1A, 24V, 80x25.5, 21dB
Digikey P/N P9739-ND, $8.25

Cool.

I just got a EP2500 and need to mod or replace the fan. I prefer to just replace it.

You wouldn't happen to know the part number for the plug that goes on the end would you?

[Dennis H]

Not sure about the plug but it looks like a standard computer power plug like you can buy at any store that builds/repairs PCs. Just take the stock fan in with you and they should be able to hook you up. Let us know what you find.

[chasw98]

Cool.

I just got a EP2500 and need to mod or replace the fan. I prefer to just replace it.

You wouldn't happen to know the part number for the plug that goes on the end would you?

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.

[ThomasW]

If a phone battery connector works I'd got a bag filled with dead batteries ready to go to the recycler. I can cut the connector off a couple and send them to you. All you'd need to do is solder it on using the leads

[SteveCallas]

Great find on that connector Chuck, that's what my Carvin uses as well. Running one of my amps for the sub is no problem, but using the second one for the mains will make the fan noise come into audibility on silent passages - with that type of connector I can do a fan mod without cutting any wires, and remove the mod if I don't care for it. The fact that you reduced the fan noise by 6db is great, but that it was 72db at 1" to begin with is crazy That's just as loud as the Crown XLS models that operate at a fixed (full) speed.

Thomas, do your connectors look just like the ones in the link from Chuck? Some phone batteries have slightly larger plastic pieces. If yours look the same, I'd really appreciate it if you could send a few my way.

[ThomasW]

Yep they're the same ones. Send me a PM with the mailing info and I'll send a couple out to you.

[chasw98]

The fact that you reduced the fan noise by 6db is great, but that it was 72db at 1" to begin with is crazy That's just as loud as the Crown XLS models that operate at a fixed (full) speed.

I have to agree. The noise is reduced, but I would like further reduction and that can only be done by changing the fan itself. I would also like to make it where minimal intrusion to stock design is involved so that if you want to sell it as original you can. My amps are rack mounted in a cabinet that does provide further acoustic dampening and I have tried to listen for the fans, but I cannot hear them unless I am right up next to the cabinet. Still, I would like to come up with "The Final Solution" and a stock connector with an aftermarket fan with a resistor in line (if needed) sounds like the right track. And if Thomas doesn't mind, I will PM him for a couple of connectors to experiment with, find an appropriate fan, take new noise readings, and update the mod on my web site.

[SteveCallas]

If I'm not mistaken, the Behringer is advertised as having a variable speed fan. The Nady models are also advertised as havng a variable speed fan, yet it seems both the Nady and Behringer are having fan noise output in the 70db+ range. Unless they are false advertising, you're right, those stock fans gotta go.

Thomas has agreed to send me a couple, for which I am thankful :T , and if I can bring each Carvin down to 47db (basically unregisterable) at 1" from the front, I'd be in great shape.

[chasw98]

"If I'm not mistaken, the Behringer is advertised as having a variable speed fan."

I have just checked the owners manual and it states on page 3 that it does indeed have "automatically adjusting fan speed for smooth operation".

To get these units down to 47db will take a very good fan. Pmazz says he bought the panaflows recommended by a rep and is happy with that model (part number listed earlier in the thread). I know on the behringers that the fan is either sucking or blowing air down what is essentially a wind tunnel from the front to the back and noise is added by that effect. Time to look for the quietest 24 volt fan out there that will move some air over heat sinks. I wonder how much air has to flow at high temperature to keep the amp from toasting itself?

[ssabripo]

chuck....seriously, I think that is just waaaaaaaaaaay to much noise to handle in your system. I think you should just get rid of the EP2500's and 1500's you got and go another route, like some QSC 1450s. I know a guy about 15min from your house, around Nob hill and Cleary, that will take them from you.

[chasw98]

Most everything in this world has a price. Make an offer

[Fryguy]

Spec Sheet

It's the FBA12G24L1A, 120mm x 38mm, 30Db-A. The amp seems cool enough. It's got a variable fan control built in. It runs at 12V initially and, according to the PCB printing, goes up to 15V. Besides, HT and music is mostly cruising for pro amps. I'm keeping an eye on it tho, as I run it with a 2ohm load.

Pete

Why do we use a panaflo 24V fan for a 12-15V app? Just to stop the panaflo from ever spinning at full speed?

Is this fan a direct replacement? IE take off 4 screws for stock fan and fit this one right in place?

[---k---]

The panaflow fan is the same size, but is designed to be very quiet - slower rotation and better fins.

It won't come with the plug connector, so you have to add that. Then it is just remove the 4 screws and fit in place.

[PMazz]

The Panaflo fan I used was for my Carver amp. DennisH posted the replacement fan for the QSC and Behringer amps, which need 80mm.

Here's the digikey part recommended for the QSC (and Behringer) amps by the QSC sales rep.

Panaflo FBA08A24L1A, 24V, 80x25.5, 21dB
Digikey P/N P9739-ND, $8.25

In my case, the Carver had a 24V fan in it. Some folks use a 24V fan to replace a 12V to reduce the speed, and the noise, much like putting a resistor in line to slow a fan. Be careful tho to make sure the lower voltage actually starts the fan spinning.

Pete

[w8liftr]

Thanks for the info.

[Fryguy]

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

And this is the connector I need for the behringer amps?