AVR-525 fan kicks on with adequate ventilation and 8 ohm speakers at low SPL levels. (1 Viewer)

I used my HK AVR-525 for the first time today. The fan came on a LOT. I'm only using a 5.1 setup at the moment, and all speakers are 8 ohm. I was running at a volume level that my Onkyo SR500 had no problems with. The receiver is out in the open, sitting on a table. It is not particularly hot in the room.

So about the fan... do you other AVR525 owners experience a lot of fan activity even at low volumes with friendly speakers?

Thanks for your feedback!!

Hi Jeff, I just got my HK AVR-325 (not 525) and running it in a 7.1 setup and 8 ohm load, and I too get a lot of fan activity. Of course, I get a lot new receiver smell too, which scared me at first, but I know this will subside. It sounds awesome but man is this a "hot" receiver (literally).

- Adrian

I went to CC to audition some speakers. The rep was using a HK AVR-325 earlier. Since I'm not fond of HK's characteristic, I switched and used an Onkyo SR700 for my audition.

I had the volume very loud in my speaker auditioning and heard a ventilation fan come on, thinking it was the store's ventilation being so loud. When I approached the receiver shelf, did I realize it was the AVR-325 that the salesman previously had on. Remember I had the volume way up and this fan could clearly be heard over the music. I just couldn't believe that they put in such a noisy fan system. I heard others complain but thought it would only be noticeable in a quiet room, not a loud room.

I've had fans in my receivers over the years and can say I had never heard them(during quite passages) with extremely loud levels on 5.1 surround sound.

The AVR-325 fan noise can be directly compared to a computer's "POWER SUPPLY FAN". VERY, very loud. Unfortunately, I had been in CC for some time and this receiver was not playing loud and was very well ventilated, as yours. The fan should not be coming on IMO.

I wouldn't had believed it, if I never heard it for myself!

Could this fan be so active because these receivers are still fairly new? I mean, I don't really know. I wonder because I am considering a 525 myself. Are there a lot of complaints about the fan noise from olders of older (more broken in) 525's?

Well, on my 325, I can't hear the fan even while the fan is venting - and I do listen to a lot of classical and piano music, along with movies...?

My 525's fan comes on once every 1.5 hours or so....

I've had my 525 for about 2 months. Honestly I have never heard the fan come on. I have it in an enclosed entertainment center with about 4 inches of breathing room from the above shelf. Maybe I have'nt heard it because it is enclosed. I do agree that the receiver runs hot, but I have'nt had any problems so far.

The fan comes on frequently. All the HK receivers at our store are well ventilated and the fan comes on every three hours w/ consistent use. We also hook up all 7 speakers. The fan annoys the shit out of me and it gets hot, but I swear they sound better then last years models which already sounded great. Also the fan is not very loud, but it's not quiet either especially when it turns on when there's no music playing.

I bought an AVR225 for my bedroom system and absolutely love the sound quality. I like to take off the cover and see the build quality of an amp or receiver when I make a purchase. When I looked inside The HK I was a little shocked at the heat sinks , they appear to be the one weakness in construction, very thin. I had heard HK's run warm so I give it plenty of breathing room and though it gets warm I have'nt encountered any problems. I am amazed at the sound of my 225, especially considering I only paid $350.00 for it. I have two older Onkyo's that were $800 each and the HK sounds as good if not better. The Onkyo's have much thicker cast aluminum heat sinks though, which I would have liked to see in the HK. I can't understand why HK goes so cheap on the heat sinks , no wonder the 325 and above require fans.

After about 30 to 45 minutes of operation, mine comes on for the first time, and then comes on about every 10 minutes from that point until you're finished listening.

I don't want to mess with returning the receiver, and other than the fan issue I like it. I think I'm going to rig up some wacky cooling mechanism with ultra-low-noise PC cooling fans to keep the loud H/K fan from ever coming on.

As a side note, I'm VERY suprised how big of a difference in tonal presentation there is between the H/K and the Onkyo. I mean, I expected different receivers to sound different, but I thought it was mostly audiophile nit-picking territory rather than something so plainly obvious. Interesting.

Thanks for all of your replies!

I briefly had an Onkyo SR500 before returning it in favor of the HK AVR225. The difference in sound quality between these receivers is night and day to my ears. The SR500 sounded so weak and thin to me I could not live with it, really bad with music in particular, nothing like the older Onkyo's. I hope the SR700 and above sound better, even the entry level HK 125 sounds amazing. HK doesn't skimp on the amplifier section of it's receivers. With better quality heat sinks I would not have a single criticism .

I have never heard the fan come on on my 525.

Why, oh why, does the 525 have to have a fan?! I mean, I know WHY it needs a fan, but why did this otherwise perfect (for my needs) unit have to include this deal-breaker! I would buy the 525 in a heartbeat, but these fans are the ONLY thing holding me back from purchasing one of these units.

Is the fan noise really that bad? :frowning: I know from these posts that people have had widely different experiences with the fan, but I wonder just how loud it really is. I mean, I'm sitting here right next to a Mac G4 (about 2 feet away from the fan), and the fan noise doesn't bother me at all - I'm sure a comparable fan in the 525 would be perfectly acceptable to me. But on the other hand, when I'm at home, my Dell Laptop has a fan that's a screaming banshee that you can hear out in the living room. If the 525 is like that, it's going back for sure.

I'm thinking of taking one home to demo with Circuit City's no-questions asked return policy, so I can judge for myself. If I don't like it, I'll probably end up going with a Denon 2803. In any case, I'd love to hear some more opinions on the fan noise, if anybody else has experiences to share.

Eric, I think that's an excellent idea, I hope it works out.

As for AVR-525 compared to PC fan noise. I have the 325 and I have a wanna-be HTPC that sits behind my entertainment center in the living room, about 3 feet away from my AVR-325 and I can tell you for sure I CANNOT hear the receiver fan when it's on. I even broke out the Raido Shack SPL meter and set it at 70db, and it barely registers, if at all.

However, when I turn on the HTPC I can hear the HTPC fan and it's quite audible. I guess I need to invest in a whisper quite power supply for the HTPC....

Good Luck!

I can definitely hear the 525's fan when it comes on. Is it as loud as the typical beige box PC? No. But c'mon... I just spent forever agonizing on a projector purchase where fan noise was a significant factor in my choice. Seems pretty silly to have worried so much about that when the fan in the receiver is WAAAAAAAAY louder than the fan in the projector.

I knew the 525 had a fan, but the Harman Kardon website product FAQ leads readers to believe that the fan should never come on unless you're playing LOUD material out of all 7 speakers.

I'll let everyone know how my auxillary quiet-fan housing for this receiver works out. I'm just going to make a little hood for the top with some ultra-quiet fans to suck out the heat. Hopefully it will keep it cool enough so that the built-in fan never comes on in the first place.

I found a comparison article on 80mm computer case fans in which the reviewer did a lab test of several fans to find the least noisy ones. I ordered a couple of those.

I was taking a good look at the H/K to try to figure out the best strategy for using these fans. I realized that the heatsink used in the AVR525 is INSIDE-OUT. That is, most heatsinks have cooling fins that reach OUT into the air around the heatsink. This way, air can carry heat away from the fins and cool the heatsink. The H/K heatsink is a rectangular box that is open to the fan. If you get a flashlight and look into the exhaust fan opening, you'll see the fins. They're not on the outside of the heatsink where convection could carry heat away, they're INSIDE the heatsink box where heat cannot escape until the fan turns on.

What a strange design! I'll use one of my fans with the hood/stack method I mentioned earlier. The idea is to suck air out the top of the unit, allowing new cooler air to enter through the bottom and sides of the receiver. If this proves inadequate (since this will not be passing air past the fins of the heatsink), I'll try to think of a way to use the second fan to push air into / out of the heatsink "tube" without modifying the receiver itself.

Jeff,

I think that type of heatsink design is used on many units that use rear mounted fans. It is not just an H/K thing.


JohnS

I agree, the fan is loud. I have found that I need at least 1" of clearance on top of it to prevent it from coming on. I placed my sd4700 on top (< .5") , and the fan came on every hour or so. I put blocks under the feet (~.5") and I haven't had it come on since.

My 525's fan comes on quite frequently too. I was concerned about it a first, but now I'm not too worried. I've pushed it pretty hard (volume as loud as -3 to -5) and it still performs and sounds quite well. Although at those volumes, certain material gets a little grainy sounding.

Mine is on a shelf in a Sony Vega TV stand. There is about 4 inches of clearance on the top and 3 inches on the left and right side. I've removed the glass doors to get more ventillation.

I can detect the fan noise at low volume settings, but I really have to be listening for it. At normal volumes, I can't say that I hear it.

The unit always feels hot after about 30-45 minutes of use, regardless of volume. The exception is when I play at loud volumes for extended periods, and particularly with multichannel music where the amp is really under a demand, the unit feels almost at room temperature. I guess that when the unit is really pushed the fan must really kick in and cool it off. At such volumes, I definitely cannot hear the fan, but I can tell you that when it's pushed, it feels cooler to the touch than at normal volumes.

Strange, eh??