Hey all - I just received my amp. Stoked. This will be my third VFET kit build, and all of them are different.
A question on case size & heat dissipation - I didnt get the case released with the kit. Im looking at getting either a 2U or 3U high case. I used a 2U high case on the "other" Sony Pass VFET push-pull amp - but of course, this amp is running in Class A (but with half as many output VFETS...). Nelson's write-up states this amp has 57 watts dissipation (is that all heat dissipation?)
Will a 2U or 3U high case be OK in terms of heat dissipation? I expect each case Im considering to be approx 300MM deep - and with both sides fully heatsinked (heatsunk...?)
thanks!
A question on case size & heat dissipation - I didnt get the case released with the kit. Im looking at getting either a 2U or 3U high case. I used a 2U high case on the "other" Sony Pass VFET push-pull amp - but of course, this amp is running in Class A (but with half as many output VFETS...). Nelson's write-up states this amp has 57 watts dissipation (is that all heat dissipation?)
Will a 2U or 3U high case be OK in terms of heat dissipation? I expect each case Im considering to be approx 300MM deep - and with both sides fully heatsinked (heatsunk...?)
thanks!
@slimecity
i have the heatsinks from the 4U, 300mm deep wich seems to be the original dimension and dissipationwise being rather plenty. But i know this can rapidly change in summer and I´m quite happy not having to be in alert mode then.
I guess 3 U might be still ok, but when it is around 27°C ambient you´ll be happier with the 4U.
i have the heatsinks from the 4U, 300mm deep wich seems to be the original dimension and dissipationwise being rather plenty. But i know this can rapidly change in summer and I´m quite happy not having to be in alert mode then.
I guess 3 U might be still ok, but when it is around 27°C ambient you´ll be happier with the 4U.
I would just go with the custom Sony VFet chassis which makes the whole project complete. I don't think there would much of a price difference over a 4U Dissipante chassis. Also to avoid any concerns of GST on imports, both the Sony VFet chassis and the amp component kit sent from the US arrived over 1 week apart which means they came in under different invoicing. ie as per 1 item shipping so there's no fear of being over the $1000 threshold when buying through the online checkout.
On my CSX1 i'm running the 5U Dissipante and it's toasty hot.
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The 4U, 300mm deep heatsinks are the same size heatsinks on the V-fet kit case. I am going to assume this is what Nelson considers necessary. The case itself is smaller then a 4U being the switching PS vs toroid and caps not used. Not a big difference in price between 3U and 4U to take a chance IMHO.
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400mm chassis here
I'm not sure if other's have noticed but I have an issue of 'heat creaking' in that 400mm chassis. Happens at every power on until temperature is stabilised and at power off. Extra tightening of the bolts does not help and i'm not sure if it's due to the heatsinks joined together. That is the heatsink for each channel (side) is made of 2 separate pieces. Though I considered the heat dissipation between the VFets to be equal on each heatsink, there still a lot of heat expansion going on. Just something to consider for those looking at the 400mm size chassis.
Amazing. QQ -- how does the logistics of this work out? Once this design has been finalized, its sent to your PCB fabricator, and they just crank them out to the tune of about a week or so, and send back your way?
Is this the same supplier of boards that you use for other projects as well?
Just a curious soul that likes to learn how the world operates.
Pass DIY Addict
Joined 2000
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I have that ticking sound on heating up and cooling down as well on a 5U/400 Modushop chassis ... seems pretty normal to me as the chassis is expanding and contracting.
Actually brings back fond memories of my childhood. Remember when we had gas-powered cars where the engines and exhaust tended to get really hot in use ?
And that ticking sound from the exhaust system after you parked your car and it cooled down ...
Regards, Claas
Actually brings back fond memories of my childhood. Remember when we had gas-powered cars where the engines and exhaust tended to get really hot in use ?
And that ticking sound from the exhaust system after you parked your car and it cooled down ...
Regards, Claas
Pass DIY Addict
Joined 2000
Paid Member
This happens with my 2016 Vfet Part 2 amp build. I am using a 3U chassis that has a single sink on each side. My first thought is that it is from the T-bracket to sink interface, but the creaking happens very soon after power on (usually, just once) and again very soon just after power off (again, usually just once). It doesn't make sense to me that any heat-related expansion of the bracket/sink interface can happen this quickly (typically within 5-10 seconds). This makes me think the creak comes from the interface between the TO-3 can and the bracket and causing the heatsink fins to resonate.
I'm just guessing here, I've not spent any significant time trying to track it down.
in some cases clicks can point to excessive heating of some part
had exact situation with 2 unfortunate Babelfish M25, where I put lesser Keratherm (by Vendors mistake I received not 86/82, and me Dodo didn't check sticker on plastic bag at all!), which resulted in BigBadaBoom after some time
had exact situation with 2 unfortunate Babelfish M25, where I put lesser Keratherm (by Vendors mistake I received not 86/82, and me Dodo didn't check sticker on plastic bag at all!), which resulted in BigBadaBoom after some time