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ZPA passive cooling
Posted: Thu Aug 21, 2014 7:49 am
by Mr. Wild
ZPA cooling fans are a bit noisy. It's not a big deal when you're cruising and the ZPAs are putting out mind-numbing crazy dBz. But in principal the cooling fans aren't in line with the high end sound quality design of ZPAs.
I have a ZPA which will probably always decorate my garage wall and also power my garage speakers. I have the fans unplugged and I was thinking how great ZPAs would be if they had passive cooling and maybe some cool looking M-style sinks.
SO here's what I came up with. A Phoenix Gold ZPAM 0.3! How do you like it?

Re: ZPA passive cooling
Posted: Thu Aug 21, 2014 8:28 am
by Blad09
Wow!!! That is awesome!!
Sent from my iPhone using Tapatalk
Re: ZPA passive cooling
Posted: Thu Aug 21, 2014 8:45 am
by trickyricky
Is this photoshop'ed? If not then how did you attached the conductors to the heat sink? It would look bad ass but still require cooling fans.
Re: ZPA passive cooling
Posted: Thu Aug 21, 2014 2:38 pm
by zeropoint0.5
i understand very good the problem about the noisy V2 adda fans.....
the fans are good......for an amp that is driven hard and playing loud all the time....
i have found a little solution in this.... in some of my zpa's i brought back an panaflo fan or a alternative
orion model i found on mouser..... to slow that fan down again i put a 27ohm/3w resistor in series on the
positive wire between the connector and the fan.....result is a fan that still blows but makes way less noise
then the adda fans......... with the resistor of that value you can go back to the V1 fan noice witch is way more
quiet then the V2 fans.....i played hard with that solution and it take a while for the amps to even get hot....
so you're safe with it.....
i would not recommand this mod playing at 2 ohm mono on sub duty....but to drive speakers at 4ohm stereo....
it will be good all day long.......
in fact it is the same story for the zx amps as the zpa's...............
Re: ZPA passive cooling
Posted: Thu Aug 21, 2014 2:40 pm
by zeropoint0.5
second of all ,, don't forget the fan's also blow air to the vertikal daughter boards....
if that is gone some resistors will probably overheat and burn............
Re: ZPA passive cooling
Posted: Thu Aug 21, 2014 2:58 pm
by trickyricky
zeropoint0.5 wrote:second of all ,, don't forget the fan's also blow air to the vertikal daughter boards....
if that is gone some resistors will probably overheat and burn............
Correcto'.... Thats why I don't think is a good idea to have passive cooling on the ZPA's.
Re: ZPA passive cooling
Posted: Thu Aug 21, 2014 7:14 pm
by vwdude
Not to mention that there's no way to connect the transistors directly to a heat sink the way they are configured. You would end up completely designing he amp in order to do it. Not worth it IMO.
Re: ZPA passive cooling
Posted: Thu Aug 21, 2014 10:15 pm
by Mr. Wild
Okay, this is just an idea I had in my head and a little bit of fun. I spent 2 minutes "photoshopping" this with windows Paint and it looks even better than I thought. I can't stop smiling
I have always loved the PG combination of white and gold, and this is just GOLD, ahh!
But in truth this could be done, if one had the right size heatsinks. The screws through the sinks to the pcb would just need to fit between the fins. All the power transistors in need of cooling lie on the same horizontal plane so the heatsinks would fit just fine. Whether the cooling would be sufficient depends on load and ambient temp. The cooling sinks would be slightly longer than on a M50, which makes almost half the power of a ZPA 0.3, so it would be in the right ballpark.
Of course I would not even consider a mod like this if it meant butchering a PG amp in any way.
btw. thanks fot the info, zeropoint! I have a V1 ZPA, but even the panaflo fans are noisy for me. The amp is right next to my sofa so I can stare at it. I doesn't get warm at all with the fans off.
Re: ZPA passive cooling
Posted: Fri Aug 22, 2014 5:18 am
by vwdude
I get what you were trying to do, and it does look cool in the photochop.
I guess I was thinking about PPI style heat sinks where you need to have about 50 psi of pressure holding the fet against the sink in order to get it properly cooled. I see what you are saying though where the new heat sink would replace the top plate/small heat sinks.
There are other fans I'm sure that are quieter. I'll bet you can do some research and find a good ball bearing fan that matches the specs.
Re: ZPA passive cooling
Posted: Fri Aug 22, 2014 6:46 pm
by vwguy3
I really like the look! Maybe if you needed a fan for the daughter boards in the middle you could put some really small ones on the ends with a push pull configuration.
GO FOR IT! LOOKS BAD ASS!
justin