Recto Filter Cap Replacement Question

[fluff191]

I am looking to re-cap my 92 Recto, and am wondering when one does a "re-cap", are more than just the 4 big blue caps replaced? Are all of the blue-colored caps replaced or just come of them? Never done a re-cap before.

I only ask because Mesa needs to know the values and how many of which ones and that kind of stuff.

Thank in advance.

 

[mikey383]

Might as well replace every electrolytic cap in the amp if you're doing it.

Looks like to me, you'll need the 4 big blue caps, the 2 smaller blue caps in the bias supply, the 2 big blue caps on the power board, another smallish cap near the bias supply (orange in the pic I have, but blue on my amp), and looks like maybe 2 more near the 4 big blues.

 

[fluff191]

Thank you mikey. I will just pull the chassis and get all the values then. Thank you!

 

[Metaghius]

Fluff don't forget to drain them first...don't want to get zapped by any cap

 

[Monsta-Tone]

I usually replace the 2 or 4 220 micro farad caps, 3 or 4 30 micro farad caps, Bias caps (usually 220 mf @ 63 volts), and sometimes the footswitch supply caps.
I've never seen a footswitch supply cap go though, and have not noticed any substantial benefit in tone or function.


The Bias cap is a "Just in case," type of deal. I replaced all of the power supply caps in a vintage Fender amp and then it developed a hum a few weeks later. Bad Bias cap that was good when it was in my shop! So now I always make it a point to change them.


The footswitch supply caps are usually a Radial type meaning that you can't get to the solder connections. I usually use a pair of channelock pliers to remove them (GENTLY!) and then re-install them at a bent over angle so I can get to the connections. George Mueller at Mesa told me about this trick. He's probably the guy you would talk to about a Recto anyway.



Make sure you read up on amp safety! http://www.aikenamps.com/SafetyTips.html
And, make absolutely sure to put the caps back in the way they should be. I accidentally installed an electrolytic cap backwards, it made a hell of a mess!

 

[mikey383]

The footswitch supply caps are usually a Radial type meaning that you can't get to the solder connections. I usually use a pair of channelock pliers to remove them (GENTLY!) and then re-install them at a bent over angle so I can get to the connections. George Mueller at Mesa told me about this trick. He's probably the guy you would talk to about a Recto anyway.

These were the last two I mentioned. I figured they would be a pain to replace, being radial types. Good tip though!

Make sure you read up on amp safety! http://www.aikenamps.com/SafetyTips.html
And, make absolutely sure to put the caps back in the way they should be. I accidentally installed an electrolytic cap backwards, it made a hell of a mess!

True dat! I would draw a diagram showing how each cap is installed before taking them out.

 

[fluff191]

So I opened the Rev. E up, and I have (4 x 30uF 500vdc), (2 x 47uF 100vdc), (1 x 220uF 63vdc).

Should I change the really long, 220MFD 300VDC caps that come right off the power supply? I know I sound like a total noob, but I am just wondering what I need to order. And those particular caps arent rated for Micro-farads.

 

[94Tremoverb]

I never change the main filter caps without also changing the bias caps - I really don't think there's any point in not doing, if you're going to change the main ones. My experience with other older amps (especially Marshalls) is that the failure rate on the bias caps is actually higher, for some reason. I don't routinely change any other electrolytic caps unless the amp is at least 40 years old, since they almost never fail in cathode-bypass and other low voltage positions.

I would not replace the caps in a Mesa at only 18 years old unless there was some definite sign of failure or you were needing to do other major work, either. But that's just my opinion.

 

[fluff191]

I would not replace the caps in a Mesa at only 18 years old unless there was some definite sign of failure or you were needing to do other major work, either. But that's just my opinion.

I totally agree. This amp looks like it was gigged and played ALOT, and has a constant hum that is getting louder with age.

And no it does not matter if anything is plugged in, what channel its on, what tubes are installed, or what part of the state you are in.

 

[mikey383]

So I opened the Rev. E up, and I have (4 x 30uF 500vdc), (2 x 47uF 100vdc), (1 x 220uF 63vdc).

Should I change the really long, 220MFD 300VDC caps that come right off the power supply? I know I sound like a total noob, but I am just wondering what I need to order. And those particular caps arent rated for Micro-farads.

IMO, if you're going through the trouble to change the filter caps, there's no harm in changing the power supply caps too.

 

[94Tremoverb]

"This amp looks like it was gigged and played ALOT, and has a constant hum that is getting louder with age.

And no it does not matter if anything is plugged in, what channel its on, what tubes are installed, or what part of the state you are in."

That does indeed sound like caps - although actually, constant use is better for them than leaving them idle. My Tremoverb was gigged hard by its previous owner too, and it's still dead quiet. Of course, you could be unlucky and have one that's actually failing (as opposed to just generally deteriorating), but at that point and at 18 years old I would change them all, too.

I suppose this is the badge of honor that these old Rectifiers are becoming true vintage amps now...

 

[fluff191]

I suppose this is the badge of honor that these old Rectifiers are becoming true vintage amps now...

I called Mesa to ask about ordering caps and he asked if I had an "older 3 Channel" amp and I laughed.

 

[Monsta-Tone]

I suppose this is the badge of honor that these old Rectifiers are becoming true vintage amps now...

Hell yeah! I hadn't thought of it that way!