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#142328 - 05/12/11 05:32 PM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: Knife]
Craig H Offline
New Member

Registered: 12/04/01
Posts: 23
Loc: Boston,MA
Originally Posted By: Knife
I don't have a preference for either, as I never used one of them. I ended up rebuilding my OEM Shicoh fan with the leads and PC board from the original and the fan, bearings and casing from a newer Shicoh.

So far, no problems but, I have the Evercool 60mm 5V Ball Bearing Case Fan, 3-pin, 4000RMP, Model: #EC6010M05CA

http://www.directron.com/ec6010m05ca.html?gsear=1 as a backup.


As you can tell if you read this thread from the top, my fan was giving intermittent noises for several years before it finally started doing it all the time, pretty loudly. Up to you if you just want to take the plunge and replace now or, wait until it's really whining.

As for doing the replacement, if you have a moderate level of mechanical skill and a decent philips-head screwdriver, it's not hard to do, at all. Once you get the DA-7 open (and the mic-pre sub-chassis out of the way - about 20 screws, in total), the fan is right there, screwed to the side of the DA-7 itself. The thing opens up kind of like the hood of a car (it opens from the the back, hinged at the front). When you prop it open there's a decent amount of room to work.

There are photos and guides (which I found a bit incomplete and lacking detail, yet still helpful) on this and other sites. I think one of the older "Fan Replacement" threads in this forum has a link to a guide - including some photos - on how to open up and replace the battery and/or fuses inside the DA-7, that you can refer to.


Thanks for the info. I did see some of those pics. Right now it's quiet again . It seems to be loudest when I first power up . Maybe needs to warm up a bit. But I'll probably get one of these fans to have on hand before I take the plunge. Just stalling before I break up my work flow.
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#142329 - 05/13/11 11:20 AM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: Craig H]
DP Offline
Founding Member

Registered: 03/15/02
Posts: 2394
Loc: Hampton Bays NY USA
However, the fan would probably just turn slower....."

And that's NOT a concern? Slower turn = Less airflow = less cooling...No? Anyone who's used a DA7 for more than a half hour or so knows that heat IS a big concern. Just take a look at how the LCD starts to disappear so you have to manually adjust contrast.

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#142332 - 05/15/11 06:51 PM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: DP]
mlange Offline
Veteran Member

Registered: 06/05/04
Posts: 1301
Loc: Brentwood, TN
Strangely, my DA7s never had a heat issue - sometimes on for weeks at a time.... However the noise floor generated by tha fan is my biggest concern. Many new fans have higher published flow rates with lower rotations.
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#142333 - 05/16/11 07:19 AM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: mlange]
DP Offline
Founding Member

Registered: 03/15/02
Posts: 2394
Loc: Hampton Bays NY USA
Hmmm, do you have the "disappearing LCD"? I just assumed this was a known issue and everybody dealt with it the same way (manually adjust contrast as the LCD heats up)...Interesting...

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#142334 - 05/16/11 01:01 PM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: DP]
mlange Offline
Veteran Member

Registered: 06/05/04
Posts: 1301
Loc: Brentwood, TN
No .... knock on wood ..... my lcd doesn't shift (much) - I might trim it a bit, bit never to the point of it being a bother. I will keep an eye on her, though.

However, there are a couple of other LCD culprits that are a drag - the Kawai K5m's being one of them.
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#142336 - 05/16/11 02:05 PM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: mlange]
DP Offline
Founding Member

Registered: 03/15/02
Posts: 2394
Loc: Hampton Bays NY USA
Wow...that's very interesting. Mine is virtually unreadable within about 1/2 - 1 hour of powering up. Once I re-adjust I'm good for several hours. I rarely do sessions that are more than 4 hrs. at a time anymore so I can't really say what happens long term (at least with my DA7).

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#142337 - 05/16/11 04:27 PM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: DP]
Knife Offline
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Registered: 07/22/02
Posts: 1501
Loc: New York
My DA-7 display requires a minor adjustment after a few minutes of warming up. Indeed, if I get the contrast knob set at JUUUUUUUST the right spot, it can be readable through the range from boot-up to fully-warmed up and I don't HAVE to adjust it. But there is a noticeable warm up and darkening/increase in contrast to the LCD display, over the first few minutes as it warms up.

I always thought that was largely independent of the heat of the other components, though. I was under the impression that that was just the LCD screen itself, warming up - and the display would behave that way regardless of the heat coming off the other components in the board. Maybe not.

I have an old Roland synth with a similar LCD display that does the same thing (and it has a corresponding contrast knob, as well). Turn it on and, in the first few minutes, you have to crank the contrast knob all the way up to be able to read the screen. A bit after that though, it becomes too dark and unreadable and you have to then turn down the contrast.

Like the DA-7 display, if you just leave the contrast setting alone after powering off, when you first start it up, the screen will be too light/bright but, it will warm up and eventually get to the same contrast as the last time it was warmed up and then you can see everything, just fine.
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#142338 - 05/17/11 07:36 AM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: Knife]
DP Offline
Founding Member

Registered: 03/15/02
Posts: 2394
Loc: Hampton Bays NY USA
Uh huuuuuuugh ! I never endeavored to find the schweeeeeet spot...on the LCD that is!

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#146294 - 05/05/14 11:49 AM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: Knife]
Craig H Offline
New Member

Registered: 12/04/01
Posts: 23
Loc: Boston,MA
Originally Posted By: Knife
I already did it.

It looks as though the terminal is there - and even more promising, the terminal appears to be linked by a trace on the fan's circuit board a tiny IC chip, which I am assuming means the fan speed control is already installed in basically all of these fans as they are manufactured, but it is just not ultimately wired up in all of them, to suit them for different intended applications.

I also ordered some of those Evercool 3 conductor, 5v fans. When they get here, I'll to a bit of experimenting with them and also with making a "Frankesnstien" 3 conductor Shicoh fan out of the lead I have on the existing, dying fan and one of the newer Shicoh fans with only two conductors wired, that I just got.

I'll keep you posted.


Been a few years since I checked back on this . But I finally took the plunge and tried replacing my DA7 fan with one of the evercool 5v fans listed here with the help of an electronics friend. Unfortunately the wire colors were different and believe we fried that resistor as neither fan fan would work now when hooked up .

After talking to another audio repair guy, we decided to try bypassing the resistor and running the fan off a separate 5 v power supply that I picked up and tapped it off the main power supply so the power switch would turn it on. This worked but the fan ran too fast and was way noisier than before and sounded like a vacuum cleaner, even the old fan sounded the same with this setup. So I guess the fan is running at less than 5 v with the resistor in place , any idea what that might be ?

Tried running the fan off a 3 v power supply and still seemed too loud and fast so thinking of trying 2.5 step down regulator off the 5 v power supply and see if that works . Its Way too loud now. Any other suggestions for a slower speed? Bad idea to just bypass the fan all together I am assuming?
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#146295 - 05/05/14 02:22 PM Re: DA-7 Cooling Fan Update - Is This Still of Interest? [Re: Craig H]
rick Offline
Founding Member

Registered: 04/16/99
Posts: 3154
Loc: Cambria, CA USA
You can insert a rectifier diode in the fan's power supply line. That'll cut the voltage by about 1v without you having to compute a resistor value. Daisy-chain a couple of diodes to get a bigger voltage cut.

Since the rectifiers have a polarity, you need to insert them in the proper direction; if you've got it backwards you'll get nothing to the fan. Flip it around and it should be OK.

Chances are that if you achieve a quiet fan speed it'll keep things cool enough.

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