CurtPalme.com Home Theater Forum

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

If I remember right I didn't tie it anywhere. I think it is just a tach sensor.

**kal** · Posted: Sat Jan 27, 2007 3:08 am Post subject:

Thanks Walter,

I was testing one of the fans with a 9V supply before installing it and it simply won't start unless I tie the sensor line to the +DC line as well.

You sure you didn't tie the SilenX sensor line to the positive line?

Kal

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

Hmm, I'll have to have a look at that and let you know.

**kal** · Posted: Sat Jan 27, 2007 2:30 pm Post subject:

Oops - forget it Walter. I'm an idiot.

The Barco fan connector has 3 pins but only the outside two are used. I falsely assumed that therefore on the SilenX connector the outside pins are the + and - voltages and the midde the control line. Not true. Doh. I'm an idiot.

Kal

v_erich · Joined: 12 Sep 2006 Posts: 76 Location: Austria/Europe

Hi Kal,

can you say something to the noise level of the Silent-X?
A friend has them in his G90, this is a good replacement in that CRT.
What is in the BArco? Is the little better noise level of the fans hearable?

Rgrd,
Erich

WTS · Joined: 08 Mar 2006 Posts: 1276 Location: Calgary

Well I would say it was an improvement over the stock fans which had a constant droning sound to them, These just have the air turbulence noise.

**kal** · Posted: Sat Jan 27, 2007 8:19 pm Post subject:

ChrisWiggles · Posted: Mon Jan 29, 2007 4:29 am Post subject:

Hey guys, sorry I'm being lazy and I am unclear as to what the right fans are. I have what I am sure are original fans in a high-hour G808 chassis that I'd like to switch out. Which fans do I purchase?

v_erich · Joined: 12 Sep 2006 Posts: 76 Location: Austria/Europe

Ok, thanks for the Informations.
Then I will try first the series resistor (0E, 5E, 10E) and then the replacement with the Silent-X.

Greetings,
Erich

**kal** · Posted: Mon Jan 29, 2007 1:31 pm Post subject:

Well, I've finished installing 4 new SilenX fans replacing the existing ones.

Barco varies the voltage supplied to the fans based on how hot the chassis gets (the sensor's in the SMPS). My hushbox is well cooled such that the fans never get more than the min +7.5V fed to them. If you run the SilentX fans out in the open vs. the stock fans, the SilentX fans are basically completely silent. The stock NMB fans have some mechanical noise to them.

Does this mean that that projector is now completely silent with new fans? Of course not. A large percentage of the noise that was generated before is still being generated: Noise generated due to air turbulence.

The difference is that now the noise is lower and is more of a 'whoosh' than a 'whoosh' with a mechanical clicking. Sorry, can't take any noise level measurements as my radio shack meter doesn't go low enough. It is quieter for sure. Not as quiet as no hushbox of course. Given the choice I'd take stock fans with a hushbox any day over no hushbox with SilenX fans. The hushbox makes a much bigger difference.

In the back I used:

(2) SilenX IXP-76-18 (120mm x 38mm/90CFM/18dBa)
(1) SilenX IXP-74-14 (120mm x 25mm/72CFM/14dBa) (the angled fan)

In the front I used:

(1) SilenX IXP-74-14 (120mm x 25mm/72CFM/14dBa) (placed on an angle with a shroud).

I took a bunch of pics so I'll put together some instructions with more thoughts/opinions.

Kal

picree · Joined: 31 Mar 2006 Posts: 351 Location: Johnson City, TN

So-kal, eventhough the SilenX spec says minimum operating voltage of 8V you found no problems at 7.5V? Did you test to see what the actual starting voltage of the fans might really be?

Curt

**kal** · Posted: Mon Jan 29, 2007 5:50 pm Post subject:

Nope! I never tested to see what the minimum was... that would have been a good idea (though I don't have a variable voltage supply here, though I could make something simple temporarily I suppose).

You say the min is 8V? Where'd you see this? I didn't find anything on their site before I made the purchase (I was specifically looking for it). Bought anyway since other Barco owners had already do so before me and not had any problems.

My exact voltage is +7.54VDC last I measured immediately at startup.

Kal

Person99 · Joined: 09 Mar 2006 Posts: 4899 Location: Flower Mound, TX

**kal** · Posted: Mon Jan 29, 2007 6:13 pm Post subject:

What someone needs to do is redesign the 808 chassis from the ground up for more efficient air-flow to avoid all this turbulence. (not going to happen).

When you pull the 3 back fans off and take a look at what they're doing, it doesn't make much sense. Some of the fans back into areas that are almost 50% just flat aluminium which probably causes most of the air turbulence.

I suppose if you could remove the back of the PJ (and leave it off), you could probably build some sort of nice baffles or something to avoid such abrupt changes in air flow. Something with nice curves in it that would allow you to offset the fans from the chassis a few inches to give you room to build curved baffles of some sort.

Though in the end, still easier to do a vented hushbox. It's amazing how much it helps keep it cool too. As I was putting the back of the PJ back on I had the hushbox venting system off temporarily since the feeder wire was disconnected and I was amazed at the amount of heat build-up around the ceiling area from only 20-30 mins of working around there.

Kal

Person99 · Joined: 09 Mar 2006 Posts: 4899 Location: Flower Mound, TX

**kal** · Posted: Mon Jan 29, 2007 7:57 pm Post subject:

Dave: How's the PJ hang down? On what?

Kal

Person99 · Joined: 09 Mar 2006 Posts: 4899 Location: Flower Mound, TX

picree · Joined: 31 Mar 2006 Posts: 351 Location: Johnson City, TN

**kal** · Posted: Tue Jan 30, 2007 2:54 pm Post subject:

Um ahhh... I guess I missed that! Smile

I was too busy looking for a datasheet with a bunch of graphs and numbers that I missed the obvious!

Anyway, they seem to run just fine at 7.5V

Kal

v_erich · Joined: 12 Sep 2006 Posts: 76 Location: Austria/Europe

Kal,
a question to your suggestet fans:
You wrote: