Replacing capacitors in Teac PSU

[lewisbowron]

Hi guys,

I've read about people recapping their Teac A-H500i amp, so I took the lid of the one I've just bought and surely enough the tops of two out of four of the capacitors in the PSU section have slight bulges to them. My first question is, do these need replacing immediately?

Second question is should I replace these like for like with 4700uF 50V caps, or would using 6800uF 63V caps offer any improvement at all?

Finally, should I be looking at replacing any other capacitors in the amp?

I've attached a section of the circuit diagram showing where the capacitors are used.

Thanks for any help in advance!

Lewis

 

[JonSnell Electronic]

There is a reason why the designer chose that value so yes, use the same value but exceed the voltage if you need to. Check the temperature rating!

 

[VictoriaGuy]

Be sure to check the lead separation (pitch) when you order the replacement caps - caps have gotten smaller over the years. A higher voltage-rated cap may have the right lead separation.
I'm assuming that these are radial lead caps that sit tight to a PCB. If not, the lead pitch probably doesn't matter.

 

[lewisbowron]

Thanks for the responses, I've got replacements for the power supply caps ordered, same capacitance, higher voltage and heat rating and they have the same 10mm pitch as the current ones. There are two more 2200uF capacitors on the preamp section that have similar plastic tops that look like they could be on their way out, so I'll have to look at those too.

Is it worth looking at ALL electrolytic caps in the amp? There are three low value ones on each of the power amplifier boards, and about 30 on the preamp board, but these are metal cap varieties.

Thanks again

Lewis

 

[Enzo]

Just a note: Larger radial filter caps, like most, are aluminum with a plastic sleeve around them. There is also a plastic disk to cover the end, the sleeve holds it in place. Over time and from heat, the plastic discs often warp and bulge, but if you slice away the plastic sleeve to free the disc, you will usually find the aluminum cap body is not bulged. So always good to check whether the cap is actually bulged or if it is just the cover.

 

[lewisbowron]

Well dont I look silly. I've just taken the top off as you suggested Enzo, revealing a perfectly flat capacitor top.

Thanks for the help

 

[TonyTecson]

if those caps are say 10 years old, i will replace them, otherwise i wouldn't bother especially if you are not having issues with your amp....and your reasoning is one out of curiosity....but hey, don't let me stop you...