Filter Cap Question

[Donnie B.]

Just bought a 33 year old Mesa Boogie.
I'm not hearing any artifacts that make me think the caps need replacing.
They look fine visually with no signs of leaking or cracks, etc.
Amp sounds great but I only have the single point of reference.
Should I replace the filter caps????

The Boogies don't have an HT fuse so I'm concerned about tranny damage
if one of them were to fail.

Thanks.

 

[glip22]

Which model did you get?

 

[Donnie B.]

Which model did you get?

Mark III red stripe SRG head.
60 watt - 2 x 6L6.

 

[glip22]

Mark III red stripe SRG head.
60 watt - 2 x 6L6.

I asked to see if it was a rare model which might make sense to sedn it to Mike B. It will never hurt to change caps that old.

 

[Donnie B.]

I asked to see if it was a rare model which might make sense to sedn it to Mike B. It will never hurt to change caps that old.

I can do the work I'm just going to be sure to use exact or as close to dupes of the originals. I've read of guys putting shiny new
caps in old amps and the tones being affected, and in some cases in a negative way.
The one common thing I've read is new cans will tighten up an amp.
Not sure I want the MIII any tighter than it already is!

 

[lockingtuner]

Just bought a 33 year old Mesa Boogie.
I'm not hearing any artifacts that make me think the caps need replacing.
They look fine visually with no signs of leaking or cracks, etc.
Amp sounds great but I only have the single point of reference.
Should I replace the filter caps????

The Boogies don't have an HT fuse so I'm concerned about tranny damage
if one of them were to fail.

Thanks.

At that age, I would definitely have them replaced by a good tech.

 

[glip22]

I can do the work I'm just going to be sure to use exact or as close to dupes of the originals. I've read of guys putting shiny new
caps in old amps and the tones being affected, and in some cases in a negative way.
The one common thing I've read is new cans will tighten up an amp.
Not sure I want the MIII any tighter than it already is!

Just make sure you do the bias caps too.

 

[dawnofdreamx97]

I just did all the electrolytic caps in my 92 mkiv combo.

I ordered the replacement caps right from mesa boogie , it was about $60 ish plus shipping for everything.

It wasn't a terrible job and I even changed the 3 dreaded radial caps as well for the footswitch power supply. Which there is a trick to do without lifting the board or taking the amp apart.

You could do a leak test on the caps with a component tester but obviously caps at that age you never know "when" could be the time. So many variables...

It was a good feeling to change them and know that my amp should be good to go for many more years to come. One of the 3 radial caps was starting to leak some fluid, so it was good timing.

I wouldn't over think it to much , it is just general maintenance. I noticed the amp was slightly quieter but otherwise sounds the same to me!

 

[Wizard of Ozz]

Change the caps. It is time. The tone will only improve. You can order them direct from Mesa. Not a fan of FT caps in Mesas.

 

[Donnie B.]

Boy, they sure do look pretty clean. I wonder if they'd been changed by a previous owner in the last 10-15-20 years or so?

 

[dawnofdreamx97]

Boy, they sure do look pretty clean. I wonder if they'd been changed by a previous owner in the last 10-15-20 years or so?

Looks like The 3 ) 30 uf caps are from 85 ... can't tell on the mallorys but prob the same... they look clean, get a component tester and do a leak test and measure to see if they are still in spec. You could also reform them as well.

Do you know if the amp was constantly used? Did it ever sit for a long time ? If not they are prob fine.

 

[SpiderWars]

Is there a tag on the side of the chassis? Mine has one from like '04 from the factory. If Mesa did it I would think they would have history.

 

[Donnie B.]

Do you know if the amp was constantly used? Did it ever sit for a long time ? If not they are prob fine.

My only gauge is by its condition, which is pretty clean for 33 years old. Very, very little oxidation anywhere and except for the pilot light which was snapped off there's really nothing major as far as dings. I highly doubt it logged a lot of stage miles.

Fixed the lamp while I had it open. Boogie still stocked the original lamp and cap.

@SpiderWars next time I have it open I'll look for markings/labels.

 

[SpiderWars]

Here's a pic of mine. I like to think it was Glenn Frey's amp.