Ok. Lexicon state that (curiously) the original spec RV8 did not have a power supply fan at all(!), but confirmed that it is normal that, once the power supply fan WAS added to subsequent models, it stayed on permanently, with no internal speed control. So, if i removed the fan entirely, i would have an original spec RV8!! Albeit with a failure-prone power supply. The only thing i can think is that it was added as a hasty and poorly designed afterthought, to deal with the numerous power supply failures that lexicon had to deal with (including my own, despite it having a fan previously!). These power supply units really seem to be the weak part of the RV8 design, despite costing so much...I'm going to make the fan speed control and 12v fan modification, as well as a soft start circuit for the power supply, and take my chances....who would have thought such an expensive and well reviewed piece of kit needed so much work?!! |
Ok i think i got this. According to my research, a 12v fan's speed is dependant on input voltage....So i can buy an ultra quiet 12v fan, then just use 24v-12v regulator from the normal power supply's (24v) power and ground feeds (leaving the fan speed sensor cable disconnected at both ends), and then just a small variable resistor, rated for the power requirements of the circuit, to step down from 12v to 5v, and back up again, depending on how much air i need to actually move to keep the power supply cool? Any advice appreciated here as im no electrician.... |
Yep i was thinking similar....there are some very quiet 80mm 12v fans, so i could just put an inline 24v-12v regulator in, and fit one of these. I see most of them have a third cable (to a resistor?) which i assume is the control? i looked at external pc fan controllers, but these seem to need their own power source? i guess i could run another 12v circuit in parallel from the inlune regulator, but this seems a mission. Anyone know of an external fan controller which works passively? Or is there an easier way to do this that im missing? |
Have a look at this web site.
http://www.newegg.com/Fans-PC-Cooling/Category/ID-11
There has to be something that will fit where your old fan is. If you're willing to run a small cable outside your Lexicon, you can control and power the fan externally.
I looked at some pictures of your RV-8 on the web and it appears to have vents on the top and sides. Another solution may to be install an external PC fan over the vents, if you don't want to go internal for whatever reason. Either way should work fine. |
I owned the RV-8 and had the same experience as Csmgolf. The constant fan noise was unacceptable. |
Thanks all. Am waiting for response from Lexicon. Will post for information. But since i bought this power supply with fan attached from Lexicon only one week ago ($800 NZ, including shipping and GST!) i am guessing they have no recent fix...i read the service manual, which suggests the fans should speed up and slow down according to power amp demands (which makes sense), but my power supply fan seems to only have one speed: noisy, whether power amp is being used or not (or even when unit is on standby)...ive never heard any of the other three internal cooling fans, which suggests to me the power supply is either faulty, or very poorly designed, despite its massive cost...any more owners' views?
Not to hijack my own thread, but im also interested to hear how many owners had power supplies that blew, and the circumstances that led to this fault (eg period of disuse). Am thinking i might have to make a separate soft start unit, which seems ridiculous for a power supply this expensive....
Thanks |
Has anyone tried asking Lexicon? It looks like its a common problem. Maybe they have a fix. |
I had an RV-8 for a while and agree that the fan was obnoxious. Mine never shut off and I eventually tired of it. Too bad, because it really was a great receiver. It was kind of hard to understand how it made it to production with a fan making as much noise as it did. All of the noise completely ruled it out for 2 channel listening for me. Hopefully you can find a fan that will work for you. There seemed to be a pretty good selection of 80mm x 15mm 24 volt fans by just doing a Google search. Good luck. |
Thanks, but 40db!!! Was looking more for the 14-20db area. Or even better, any advice from rv8 owners as to whether this is normal for the power supply fan (which has just been replaced, along with the power supply) to be running on full tilt permanently, even on standby....? |
Not 13mm, but 15mm from Digikey:
http://www.digikey.com/product-detail/en/G8015X24B-RGR/1570-1098-ND/5209795 |
Yep thanks but i cant find any good, quiet 80mmx80mmx15mm (or more like 13mm, with NO headroom) 24v fans...
No settings in rv8 to change fan speeds; it should all be automatic, according to service manual.
I left the amp on standby all night, and the fan was STILL running at full speed this morning, so im thinking there must be something wrong here...can anyone confirm who has owned the RV8 before?
Many thanks in advance |
If the fans bother you that much, I would try and swap them out with some silent computer fans. You just have to make sure you pick ones that fit where you need them.
Also, check the RV-8 over and make sure none of the air vents are blocked with anything. That could cause the fan to run more.
Try checking the owners manual as well. You may be able to adjust the fan settings right in the menu system. |
