# Need help picking capacitors for Adcom GFA-5450 amplifer



## ppia600 (Jan 1, 2016)

I'm replacing all of the capacitors in my Adcom with 105c capacitors and have so far found Panasonic and Nichicon with matching sizes for most. I wanted to upgrade the storage in the 12v section and high voltage rails end but couldn't find anything short enough to clear the covers. 

-Has anyone replaced the power supply caps with higher uf versions and had good cap to cap and cap to cover clearance? 

The largest caps appear to be about 30mm tall and 20mm in diameter, so I've found some that are 35mm tall and 22mm to replace the 12v end with. The originals are 16v/4700uf and there are 16v/5600uf replacements that will clear.
In the high voltage end, should I just replace them with the same uf capacity? I'm not sure replacing those with more storage will help, or be worth any slight improvement. 

Also, I can't find any 16v/4.7uf 105c caps for the output transistors. Only 50v/4.7uf keep appearing in searches. I did find some overseas, but there was no branding and I'd like to at least have a chance with a decent brand.

The last question was on the type of pins the large power supply caps use, are they snap in type with the wide spaced pins or the normal type with the thin 7.5/8mm space pins? The snap in type are way more pricey but if they have to be used I will go that route. If the thin lead ones work correctly obviously I would rather use them. 

Thanks for any help, I'm currently running the amp in my car but since the caps are obviously ancient I'd like to renew them. I also plan on reinforcing the main power traces under the board with braid, to prevent any issues. The power supply fets and diodes have already been replaced by the previous owner, I could see where the traces were repaired. 

Thanks for any help


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## ppia600 (Jan 1, 2016)

https://pbs.twimg.com/media/CR7iiuWWwAE64Wl.png


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## ssclassa60 (Jan 28, 2013)

Sub'd as I have this same amp...
And Adcom will not support any of their car stuff any more. Just the way it is. They were only in the game 3-4 years


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## wheelieking71 (Dec 20, 2006)

The large caps in ADCOMs, the input filter caps, and rail stiffening caps, are indeed of the snap-in variety. And, they are a royal pain in the ass to remove without damaging the board. If you are not a pro, plan on dealing with missing solder-pads, and pulled vias. These boards are very fragile. I honestly have never seen one of the factory snap-ins fail, or leak. That is not to say I haven't replaced, and or had many of them replaced. But, if you aren't seasoned, you stand a good chance of damaging your precious board!

These large caps are not in the audio path, and really, there is very little benefit from replacing them.


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## ppia600 (Jan 1, 2016)

Thanks, knowing what type they are will help a lot. I'm replacing them because they are practically ancient, and will be reinforcing the traces for reasons mentioned in a few threads. Removing and installing them won't be a problem, I have a good bit of soldering experience. I've read of others replacing the power supply end caps and yet no one who's done it has replied to me despite messaging every person who's posted about it. 

I was just trying to confirm type, to avoid wasting money and time. This amp will be the one driving my components and it needs to have a sporting chance.


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## Dubstep (Apr 7, 2010)

Stick to something close to the uf of the stock caps. Doubling the UF 'can' be a bad thing... Panasonic TSHA series are great caps! Nichicon, Elna, CDE, Kemet are a few companies that have good reps. there are more. Digikey is where I get my caps. You wont notice anything different with just a cap change. To renew the amp, its a good idea as the stock caps are what 20yo now.. I see you have been warned about the boards being fragile, take heed to that!


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