CurtPalme.com Home Theater Forum

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

and I haven't put up a picture yet....but my comment is that this is a very quiet projector...it has the slightest edge to the fan sound, but compared to all others I've had, this is by far the best.

Now...about fan design in the chassis. Is it just the 3 or 4 fans at the back of the projector that throw the air out?

If so...Could I not build a simple plenum with one or 2 big quiet fans that pull the air out of the chassis? This might be a simple fan mod that gets me to a very, very enjoyable sound level.

If the picture is half ways decent...I think the BG808s chassis will finally be a keeper!

Next step...colored glycol.

Ben

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

zGman · Joined: 22 May 2006 Posts: 599

"" the picture should be very good. Its also one of the best looking CRT PJs made. ""

Totally agree with Dave on this one -

G

Ile · Posted: Thu Dec 11, 2008 9:48 pm Post subject:

HaydnG90 · Joined: 22 May 2006 Posts: 1356

I found the BG808s to have the least objectionable noise of any pj's I've seen. The G90 on the other hand......

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

No pic yet because I don't think this crappy transcoder will work with it....I'll hook up a pc tonight or tomorrow.

Fan speed would not be likely to increase if

a) I used 1080i
b) I have an air extraction duct on the ceilling

and once I have b) I am then very close to being able to throw a hushbox on it. I can't even imagine having a near slient crt projector...it would be a thrill for sure!

I think I'll put a diode on the fan lines, and hushbox it with an extraction fan...that should make it virtually silent!

**kal** · Posted: Fri Dec 12, 2008 1:04 am Post subject:

Don't replace the 3 fans on the back with 2 bigger ones (if that's what you were planning on doing). They're pretty strategically placed to pull air over the main heat sinks.

Given that the fans are speed controlled based on the the temp of a heat sink in the SMPS, if you slow down the fans with a diode, the PJ will just compensate and run them harder so slowing them down does not work.

You need to hushbox it and build something to evacuate the air if you want to make it quieter.
That's what I did. See: http://www.curtpalme.com/Hushbox1.shtm

Kal

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

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

she's definitely a keeper then!

Did any of you Barco dudes have trouble getting a stable pic from a PC? I'm currently testing with my laptop and it's proving difficult to get a stable image. I think the porches are too small, but I can't adjust them with the projector....hmmm. Maybe I'll try a composite or s-video source.

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

Tom.W · Joined: 09 Mar 2006 Posts: 6635

secstate · Joined: 20 Mar 2006 Posts: 720

I agree with Dave the 120x series is signficantly quieter than the 808 series. On the fans the one in the front on the convergence tray and the middle one in the back make the most noise. I put a wire round resistor (forget the specs) on the back middle fan and that really took the edge off of the sound of the fans (I sit behind the projector). The projector did not appear to compensate for this change and other have reported similar benefits. That said you run the risk of running the projector out of spec (hotter) and blowing something up. I haven't had any problems in 500 hours but YMMV, you pays your money and takes your chances. It was worked great for me and I have an entire spare chasis if something blows up.

I did the colored gycol mod in my 808s Data along with adding hi-res tubes and continous lens flapping. The colored gycol, followign Brjorn's mix your own worked great for me. It still looks good 500 hours later (others have reported fading, mine has not faded so far). That said I would do the lens mod referenced by Kal if I had to do it all over again. My projector was already mounted and with color gycol when the lens mod came out for Barcos. There was no way I was going to unmount it remove the tubes, drain the colored gycol and remount it 12" closer to the screen.

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

I think I'd prefer the colored glycol...I can't spend more on lenses and lense adapters than I spent on the entire projector. I just can't do it Smile

Besides, I really don't think the 144/5's would be a huge difference for me. I think the difference comes in the color filtering for me...and the glycol is a lot cheaper.

I will definitely take the edge off the fans...I don't really care if I blow something up. It would probably take me 3 years to put 500 hours on it anyhow. Can anyone suggest the resistor to use?

zGman · Joined: 22 May 2006 Posts: 599

by far the noisiest fan in the 808 is the convergence tray - it has its own temp control circuit
and the airflow is so poor that it goes to full speed and has no effect.

If you like some work, it is possible to remove the bottom panel and cut holes directly under
the heat sinks for the conv output STK chips .

Panasonic makes some 10mm thick 80mm 0.07A fans that can be mounted there and in place
of the stock one as well. run in parallel, they will cool better and be a lot quieter.

I will try to find some pics.

G

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

I have to agree that the convergence fan is the worst. What I did was replace the 3" unit with a 4.5" unit layed at an angle(pointing upwards) and cut out the expanded metal at the front of the fan. It runs faster, moves more air and is alot quieter as in I can't even hear it now. I just used tiewraps to hold it in place.

As for the back fans, I replaced the two flat mounted ones with Silenx fans with rubber mountings and it did make it quieter. I also lined the swing down cover with a heavy furniture type padding to dull the noise coming through the cover and that helped ad in noise reduction. Anothe rthing I did was remove the expanded metal piece that fits around the lens to allow more air flow from the front. Then I covered the side vents which cause the air flow to come from the front around the tubes/neckboards then exhaust out the back. I checked the air temp of the air coming out the back with a very accurate SS sensor and after about 4hrs running the temp was well under 30C.

Of course this is all assuming the 808s has the same chassis layout/setup as the Cine8, but i think it does.

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

10mm fans? that's pretty thin, I can't imagine they move alot of air. The Silenx fans I used are the thicker ones, I think they were 1.25", were as the stock one were 1".

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

Tom.W · Joined: 09 Mar 2006 Posts: 6635

Get over it Dave ! Lets face it......You've been infected by A deadly strain of digitalprojecterosis that's going around and your the next victim... Mr. Green

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

Don't feel too alone Dave we'll all be there some day. But I won't be until they come out with something other than the light sources they have now.

benareeno · Joined: 22 Mar 2006 Posts: 1614 Location: ottawa, canada

I can tell Dave is still interested in crt...

digital is close and virtually on par in so many respects...except that there's no hobby around it. It is what it is.

Sounds like I can get the Barco quite quiet without a hushbox...again, this could be a keeper. If I can get it to synch properly!!