# Need to find Electrolytics



## LaRSin (Nov 27, 2006)

*61-62 Bandmaster*

I just got a 1962 Bandmaster Head in rough shape and need to replace the Electrolytics first, anyone know where I can find a place to get them and what kind (mallory)


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## nonreverb (Sep 19, 2006)

The Tube Store...Sprague atoms (blue ones). They aren't the cheapest but the best for this application.


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## DavidP (Mar 7, 2006)

Friendly suggestion: since you're pulling those caps anyhow, I'd also replace those cc resistors with some flameproof metal film 2 w resistors. Those cc's are most likely way out of spec given their age and the heat in there. At least that's what I do for preventive maintenance when I recap an old amp .


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## keeperofthegood (Apr 30, 2008)

If you are pulling those caps out, Id pay the postage and cost of a bubble envelope for them.

Also, I deal with Dave: Tube Radio Capacitor Shopping Cart

And I have a new source for electrolytic.


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## LaRSin (Nov 27, 2006)

Thx for the sugestions , I have been looking at the atom sprague caps


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## GuitarG. (Apr 1, 2010)

Sprague Atoms. That's what I generally use too.


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## Shiny_Beast (Apr 16, 2009)

keeperofthegood said:


> Also, I deal with Dave: Tube Radio Capacitor Shopping Cart


What kind of electrolytics does he sell? I might need some if he 33uf 350 volts


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## keeperofthegood (Apr 30, 2008)

I am on the Wild Bill side of the "it's just a capacitor" fence. 

Hey it is all good, now I have a source for better caps, and for about 60 cents each.


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## dtsaudio (Apr 15, 2009)

> Todays package was Taiwan Ultra Capacitors. Wu Jih Manufacturer, Exporter


One word - Boom. 
While I don't necessarily subscribe to high prices of some caps. I've had to replace hundreds of these Taiwan, H/K caps over the years in a wide variety of equipment. They just don't meet their ratings and have a very short life. For cheap and quick projects they're fine. In a 62 Bandamaster - Sprague Atoms.
P.S. Best cost to performance cap - Panasonic


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## nonreverb (Sep 19, 2006)

dtsaudio said:


> One word - Boom.
> While I don't necessarily subscribe to high prices of some caps. I've had to replace hundreds of these Taiwan, H/K caps over the years in a wide variety of equipment. They just don't meet their ratings and have a very short life. For cheap and quick projects they're fine. In a 62 Bandamaster - Sprague Atoms.
> P.S. Best cost to performance cap - Panasonic


+1 on that! Look, in theory you get about 20+ years out of good quality caps. Why not spend a little more and get piece of mind? I've had to change those Taiwan caps due to premature failure as well. That amp is a valuable, collectable piece. Don't risk potential damage just to save a couple of bucks IMO.
I use Sprague Atoms in all the Fenders I restore...period. I don't want the risk of any failures. Not in my amps or my customers.


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## LaRSin (Nov 27, 2006)

DavidP said:


> Friendly suggestion: since you're pulling those caps anyhow, I'd also replace those cc resistors with some flameproof metal film 2 w resistors. Those cc's are most likely way out of spec given their age and the heat in there. At least that's what I do for preventive maintenance when I recap an old amp .


the 2 watt resistors , what ohms would you suggest ?

looked it up , it's ok .


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## LaRSin (Nov 27, 2006)

what resistor would you recommend to replace this on the power tube socket ??


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## keeperofthegood (Apr 30, 2008)

dtsaudio said:


> One word - Boom.
> While I don't necessarily subscribe to high prices of some caps. I've had to replace hundreds of these Taiwan, H/K caps over the years in a wide variety of equipment. They just don't meet their ratings and have a very short life. For cheap and quick projects they're fine. In a 62 Bandamaster - Sprague Atoms.
> P.S. Best cost to performance cap - Panasonic


AH! Well fair that and good point!! Can you PM a link/source? I need about 100 8uF caps *fear* so the cost has to be manageable at best!!



LaRSin said:


> what resistor would you recommend to replace this on the power tube socket ??


Same as what appears there. I would say that is either a 2 watt 47 ohm or 2 watt 470 ohm resistor, only because I cannot really see what the third band colour is. If black then it is a 47, if brown then it is a 470.


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## nonreverb (Sep 19, 2006)

470 ohm 2 watt. Don't replace with carbon comp either. Use better quality like metal film.


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## LaRSin (Nov 27, 2006)

the colour code Yelllow Purple Brown Silver 470 ohm..

Thx guys


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## keeperofthegood (Apr 30, 2008)

Yellow =4
Violet = 7
Black = 0 * 10

It is a 47 ohm resistor, the silver bank means 10% tolerance but gold band 5% is fine too.


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## LaRSin (Nov 27, 2006)

It was the watts (2) I wasn't sure of , Thx again


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## nonreverb (Sep 19, 2006)

keeperofthegood said:


> Yellow =4
> Violet = 7
> Black = 0 * 10
> 
> It is a 47 ohm resistor, the silver bank means 10% tolerance but gold band 5% is fine too.


WRONG!!! Fenders use 470 Ohm resistors for the screens. No offence, but bad info can lead to bad outcomes...


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## LaRSin (Nov 27, 2006)

nonreverb said:


> WRONG!!! Fenders use 470 Ohm resistors for the screens. No offence, but bad info can lead to bad outcomes...


not his fault , I put black then edited it and put brown , At the same time he was answering my post sorry about that , didn't notice till it was posted , thought I got it in time ..


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## Stratin2traynor (Sep 27, 2006)

nonreverb said:


> 470 ohm 2 watt. Don't replace with carbon comp either. Use better quality like metal film.


Interesting. I'm replacing some caps and resistors on a Silverface Champ. Just waiting for everything to come in the mail. Curious - why not carbon comp. Does it boil down to reliability? To be on the safe side I ordered both carbon comp and metal film for my project. For the caps I ordered sprague atoms from TheTubeStore and the rest from Watts Audio in the states.


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## Wild Bill (May 3, 2006)

Stratin2traynor said:


> Interesting. I'm replacing some caps and resistors on a Silverface Champ. Just waiting for everything to come in the mail. Curious - why not carbon comp. Does it boil down to reliability? To be on the safe side I ordered both carbon comp and metal film for my project. For the caps I ordered sprague atoms from TheTubeStore and the rest from Watts Audio in the states.


I've posted this a couple times before but it bears repeating! Here goes!

For decades carbon composition was the standard type of cheap and dirty resistor for ratings up to 2 watts. They were made by molding and compressing a paste of carbon granules. The density and overall length gave the resistance value. It was not just a cheap and dirty solution but basically the ONLY solution!

Unfortunately, their very nature always gave some problems. After they got heated a few times they would drift in value. Over the years the drift could be considerable! Also, they had a nasty tendency to start arcing inside, causing excessive hiss, snap, crackle and pops in amps. In extreme cases, when they burned out from an overload they would burst into flame! Old time techs used to make jokes about using them to light their cigarettes! To be fair we should keep some perspective. They were invented in the late 1920's, after all!

It wasn't till the mid 1960's that new technology provided something better in the form of film resistors. First carbon film, then metal films and for a couple of watt ratings they invented metal oxides. ALL of them blow the doors off carbon comps for being quiet and noise free! They do NOT burst into flame and most of the time they don't drift much in their values either!

Almost immediately the mainstream electronics industry bailed out on carbon comps in favour of the new film types. Carbon comps rapidly became a specialty part with really only one customer...the military!

The military has always had the problem of being very slow to react to new technologies. They have tons of paperwork to approve each and every part, from a cockpit of an F22 fighter jet to a 1/2 watt resistor on a circuit board. They would much rather keep working with the old, approved parts forever then have to go through the time and expense of getting something new approved. The fact that the new part is better is not considered important!

There's a popular myth out there that mil spec stuff is better quality. I saw first hand that while it might mean a tougher cabinet to house the unit the parts inside were often of much poorer quality than the ghetto blasters you could buy at RatShack! Few laymen know that the Space shuttles fly with IBM 286 computer chips! The reason they never used anything newer is that the 286 was the last version that Intel was willing to get mil-spec certified. After that they decided that the military didn't buy enough volume to make it worth Intel's while to pay for the mil certification!

Anyhow, eventually only one manufacturer would still make them, Allen Bradley. I worked in the late 90's for the last AB resistor distributor, selling 1/2 watt carbon comps to military accounts for nearly $2 for each resistor in small quantities! The profit was fabulous! They could have bought modern film resistors for $2 per hundred! They didn't care. They just kept to their own paperwork and plodded on. Finally AB decided that even with such a huge profit margin the volumes were still too low and they shut down their plants. The military accounts were given a last "lifetime buy" opportunity and that was it. They were now forced to qualify modern parts.

It was not surprising that with the prices kited so high the guys in the audiophile business who sell $1000 power cords and $100 coupling caps would see an opportunity. The mojo started to go around that carbon comp resistors sounded better! Every real tech knew this was crap! Resistors are not tone devices. To change tone you have to be frequency dependent. You have to treat lows, mids or highs differently, or add distortion. Resistance does none of those things. It simply cuts down a voltage or some current flow, to all frequencies equally. It didn't matter. Old stocks of carbon comps started to be sold at a ferocious ripoff price! Small specialty manufacturers began to make new ones. The quality was often scary! A buyer at a military account, Litton Systems in Toronto, showed me some he had bought to finish a mil-spec job. Some of the leads had fallen off the resistor bodies in the package!

You may have seen an earlier post of mine about an article written by R G Keen. He's a true electronic genius who tested carbon comps for any differences in the typical guitar amp and wrote an article about it. He found that only in rare cases where you had an amp cranked and a carbon comp in a point of the circuit that passed a lot of current could you even measure a very SLIGHT change in the resistance value under load! This change was so low that it was doubtful if there was any human being alive with "super bat ears" who would even notice a change in the tone. Ordinary folks certainly never would. Again, there were only two positions in the typical amp where this could happen, which were the plate resistors of both halves of the phase inverter.

Here's a link to R G 's site: New Page 1 

It's a great site with TONS of techie stuff and construction articles on music accessories, like effects. Or tips like "The Tube Amp De-Bugging Page".

So that's the scoop! If you still want to pay those outrageous prices for carbon comps that's your business! It's a free country, after all. Those guys selling audiophile parts have to pay for their cadillacs somehow!

As a tech, they make me money! Guys keep bringing me amps with carbon comps that hiss and spit really loud. I yank out the carbon comps, replace them with modern films and the amp is quiet as a mouse!

Then I write up the bill! kkjuw


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## keeperofthegood (Apr 30, 2008)

nonreverb said:


> WRONG!!! Fenders use 470 Ohm resistors for the screens. No offence, but bad info can lead to bad outcomes...



 none taken! In the photo, I really cannot tell if it is black or brown, and he had said black at the time. Black band would have make me correct, but I see he put that down in error.


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## LaRSin (Nov 27, 2006)

All Parts have Been ordered ,

Most from from the tube Store , they were very good to deal with , 
http://thetubestore.com/

The rest from Huffman , He was also good to deal with , let you know how long it takes from there.

http://www.hoffmanamps.com/

Tried dealing with The Radio store, But it was nothing problems , wouldn't recommend it .


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## LaRSin (Nov 27, 2006)

*61-62 Bandmaster*

started a new thread


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## parkhead (Aug 14, 2009)

Boom..... is the best reason to avoid asian caps 

there have been heaps of examples of these caps failing very early 

in one case it was suggested that the Japanese felt that another counrty was stealng their cap designs 

so they purposely put incorrect info in their design drawings... as a result all of the stolen cap designs 

went boom ... confirming the suspicion of industrial espionage 

the other factor is the "chinese night shift" 

most chinese factories run a night shift where they produce cut rate clones of the goods they make during the day 

the stuff is not the same since every possible corner is cut to meet the low grey market price points,

When buying US, German or brand name Filters you are avioding all of this malarkey 

you think they play games with toothpaste and childrens toys... what's in your mystery cap? 

p


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