# How do you read this for date code?



## Tone Chaser (Mar 2, 2014)

These are caps in my 1978 Garnet Session Man. The two blue caps are the same and for MFD it said 80 before I somehow smeared it by touching it. Both silver metal caps are the same. Anyone know what the date on these parts are? Thanks in advance.


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## nonreverb (Sep 19, 2006)

The Mallory cap "might" be 102 day of 1973 although codes for components made in Canada can be different. The Japanese made one is a mystery. Their coding system was completely different AFAIK.


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## Wild Bill (May 3, 2006)

I agree with nonreverb about the Mallory. Since Garnet was a Canadian and made amps in relatively low volumes he probably picked up that electrolytic from a domestic supplier to the repair industry. Large volume manufacturers in those days would buy direct from the factory and the parts would not be much older than the amp itself. They would come off the assembly line and be shipped to the end customer. He would likely be installing parts within a few weeks at most on his production line. Inventory is expensive. You don't want it sitting around. You use it to build your end product and you ship it out the door to get your money as fast as you can!

I'm curious - why are you asking? These are electrolytic caps. They were never expected to last that long anyway. They have a paste inside that slowly dries up and by definition they are perishable. There are amps out there with original electrolytics in the power supply but the original guarantee was for 5 or 10 years. I've seen Silvertones with such caps inside clearly marked "One Year". As I said, they can last much longer but you're on borrowed time.

If you are getting power supply hum louder than you can stand then you have to replace them. Is there another reason you haven't mentioned?

Wild Bill


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## Tone Chaser (Mar 2, 2014)

The amp still runs quiet. I have been considering taking the amp in for a check up with the tech. It is not lacking power, but may be lacking some sparkle. It has been sitting for a number of years. I also have several other amps waiting for me to have a surplus of cash for the tech. There are many decisions I have to make. Which amps will I likely keep? Which amps might I sell.

The silver caps are made by Shin-Ei, the company that made the famous '60's Super Fuzz pedal. The blue caps may be 1973.
The amp is a 1978, is very clean, and in many ways looks too new for its age.

I am likely over thinking things.


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## Wild Bill (May 3, 2006)

Tone Chaser said:


> The amp still runs quiet. I have been considering taking the amp in for a check up with the tech. It is not lacking power, but may be lacking some sparkle. It has been sitting for a number of years. I also have several other amps waiting for me to have a surplus of cash for the tech. There are many decisions I have to make. Which amps will I likely keep? Which amps might I sell.
> 
> The silver caps are made by Shin-Ei, the company that made the famous '60's Super Fuzz pedal. The blue caps may be 1973.
> The amp is a 1978, is very clean, and in many ways looks too new for its age.
> ...


39 years old! Well, it can do no harm to run them until they finally start to break down. I'd just leave them alone!

You may already know that filter caps like these do not affect the tone, unless they are no longer working properly. Their purpose is to smooth out the rectified voltages from the power supply rectifier. Tubes need reasonably pure DC power. A rectifier by itself gives pulses, not a steady voltage. Different brands of electrolytics will not sound different, as long as the values are similar. 

I'd just play the damn thing! Why look for trouble! 

Some audiophiles that have little or no technical education are all hung up on amps having all original parts. They have been known to insist on original OLD filter caps! This is like finding a '57 Chevy behind a barn and after taking it to a shop for restoration insisting that they keep the original tires on it! Electrolytics are one of the few perishable from age types of parts in your amp.

Wild Bill


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