Ugly mid-60s Bassman...need some help

[B. Roth]

Hi Everyone,

I orginally posted a thread similar to this on the Les Paul forum, and I was pointed to this board. I want to get some opinions on my mid-60s Blackface Bassman.

Admittedly, when I bought this amp, I knew little to nothing about amps. It sounded good, but cosmetically it ain't too pretty. The tube chart looks like someone tried to remove it a long time ago and only got about 50% of it off. Its grillcloth looks like it sat in a smoke filled room for the past 35 years. But when I got it, it sounded fine.

A few years ago, I was playing in a band and used to leave the amp in the basement we rehearsed in. Unfortunately the basement flooded (the amp was not directly in the water but it was VERY damp down there for a long time). When the flood subsided, the amp started blowing fuses when I started it up. Sometimes they blow after 20 seconds of playing after the tubes warm up, and sometimes they blow after less time. I put it aside meaning to look at it when I had some time.

A week ago I decided to see what was going on with this amp after not using it for a couple years. I opened up the amp for the first time ever and unfortunately I was shocked at what I saw. I've never seen an amp with an interior in worse condition. I took a picture of it and it is at the following link http://www.lilypix.com/photos/data/4...94_p26489.jpeg

As you can see the inside is very rusty. Obviously the tube sockets need to be cleaned/replaced and the amp needs a good scrubbing. Also the transformer is rusting so I either need to see if I can remove the rust or I might have to buy a replacement Tranny.

I'm posting this to see if anyone has any suggestions for me. Is this a good amp for me to try to rebuild myself with no prior Tube amp knowledge? Would anyone suggest that I send it away and have it restored? My thoughts are that it would probably cost me more to have someone else restore it than it would cost to replace. But if I rebuilt it myself I could get a working amp and a lot of knowledge out of the project. Please give me some opinions.

Thanks a lot!

B. Roth

[grito]

With that kind of pitting, i'd strip the chassis down or have someone do it. I'd have the electronics go through it. Sounds like a short somewhere.

[BlueFrogs]

Hi B.Roth-
Here is a list of problem solving suggestion from the Firebottle site (Click Here). If you do not have any experience at all I would probably not try and rebuild this as my 'first' amp. If you do have some sort of electronic experience, the schemtaic can be found at the Ampware Site (Click Here). Remember, safety first. Other useful links:

Ampage
Plexi Palace
DIY Page

Good luck!:)

[BLUELOU]

I LOVE THEM AMPS
BLOWIN FUSES !!!! READ THIS
SORRY I TYPE IN CAPS

THERE IS A METAL 4X6 COVER ON THE UNDERSIDE OF THE CHASSIS FRONT OF AMP FACIN FORWARD

UNSCRETW THE 4 SCREWS SET THEM ASIDE DONT PLUG THE AMP IN OR ANYTHING

LOOK AT THE RESISTORS AND CAPACITORS THESE GET NASTY WITH AGE
AND FROM THE LOOKS OF YOUR AMP PICTURE
I'D SAY YOU HAVE ALL THE ORIGINAL FILTER CAPS
ETC UNDER THA COVER IF THEY ARE ORIGINALS MALLORYS PROBABLY 99%TIME BROWN PAPER COATED ONES REPLACE THESE ALL....
LOOK AT THEM ALL IF THERE IS PIMPLES WHICH THERE WILL MOST LIKELY BE
ON THEM TOWARDS THE POSITVE END THESE ARE SHOT AND IF ONE IS BAD I REPLACE ALL

IF THEYRE RUPTURED= NOOOO GOOD PROBABLY CULPRIT...
LOOK AT THE ALL THE 4 RESISTORS ALL
IN FRONT OF THESE CAPS (FACIN THE POSITIVE) END
OR FRONT OF YOUR AMP

THESE BLOW OUT OR RUPTURE WITH AGE ALSO
THEY MAY LOOK GOOD
BUT THEY CAN BE BAD
ESPECIALLY AT THAT AGE

HERE IS A IDEA NOW
THEY ARE LARGE 2 WATT RESISTORS ...... THERE IS 4 ALL TOGETHER ON THE CAPACITOR BOARD

FIRST ONE IS A BROWN BLK RED/SILVER
THIS IS A1000 OHM RESISTOR FROM CAP 3 SOLDERED TO CAP 4

2ND ONE IN FROM CAP 4 TO CAP 5 IS A YELL VIOL RED /SILVER 4700 OHM ONE

THEN FROM CAP 5 TO -CAP 6+ CAPACITOR IS A RED VIOLET ORANGE/SILVER 27,000 RESISTOR 27K

HERE IS THE TRIKY PART IN BETWEEN THE 2ND LARGE CAP TO THE 3RD MID SIZE ONE IS HIDEEN
A RED RED YELL/ SILVER 220,000 OR 220K RESISTOR LOOK ALL THESE OVER CAREFULLY

IVE SEEN THE VERY FIRST OUTER ONE (WITH AMP FACIN FORWARD BACKSIDE TO YOU) UPSIDE DOWN
THIS 1000 ONE BLOW UP
THESE RESISTORS GET OLD BEAT FROME HEAT
AND BURN UP IN TIME MAKIN THE AMP POP FUSES

JUST MAYBE YOURE POPIN FUSES FOR STUPID OLD BEAT CAPS OR RESISTORS UNDER THA COVER
AND THEM RESISTORS USUALLY THE CAPS LOOK BEAT ON ONE END OR JUST EXPLODE REMEMBER
THEY ARE UNDER A COVER SO ITS HARD TO TROUBLESHOOT
TILL YOU POP OFF THA COVER
I LIKE TO WORK ON MY CAPS SECTION (FILTER CAPS) WITH THE CHASSIS FRONT OF AMP FACIN FORWARD BACK TOWARDS ME
THAS MY PREFERENCE
IF I GO INSIDE AMPS I
USE WOODEN STICK LIKE A OL CHOP STIK OR SOMETHIN LIEK THAT TO POKE AROUND IN THE CIRCUIT BOARD
OF THA AMP
SHUNT ANY POSITIVE CAPS OFF WITH A WELL INSULATED SCREWDRIVER
TO THE POSITIVE OF A CAP TO GROUND (CHASSIS)

MAYBE YOU JUST GOT BAD FILTER CAPS THEM ARE A RITUALISTIC REPLACEMENT FOR ANY OLD AMP
EVERY 3-10 YRS DEPENDIN ON ITS WORK LOAD
I CHANGE ALLL MINE PERSONALLY
EVERY 3 YRS NO MATTER WHAT
THE CONDITION OF THEM IS
A GOOD HORSEHAIR PAINTBRUSH WILL
CLEAN UP LOTS OF THA CRUD
INSIDE
AS FOR SHORTS IF IT WAS
IN MILD WET ATMOSPHERE AS YOU SAY
MAYBE THE WIRING IS ROTTED
IT HAS CLOTH COVERED WIRE PROBABLY
AND IT MIGHT HAVE SHORTED OUT
ITS ONLYCLOTH COVERING CLOTH ROTS IT AGES

KEEP IT IN A DRY PLACE
SOUNDS LIKE A FILLTER CAP IS SHOT
THESE ARENT TOO COSTLY IT IS COMMON ALSO
JUST REPLACE ONE AT A TIME IN EXACT LOCATION

DONT JUST CUT ONE OUT WITHOUT PAYIN
CLOSE ATTENTION
TO POLARITIES THESE ARE MARKED LIKE A C SIZE BATTERY POSIVE+ AND NEG_

JUST BE CAREFUL PROBABLY YOUR AMP WILL FIRE UP WITH A VERY LITTLE TLC
LOOKS CAN BE DECIEVING

MAIN THING I WOULD DO IF I WAS YOU IS LOOK UNDER THA METAL 4X6 CAPS COVER
AT ALL THEM CAPACITORS
THEY LOOK LIKE BATTERIES

WELL THEY ARE IN A WAY
THE FIRST 2 LARGEST ONES=ARE USUALLY THE CULPRITS


NOISEFULLY
BLUELOU
GODBLESS
GOODLUCK
NEED PARTS HOFFMAN HAS THEM CHEAP

USUALLY THA PROBLEM LIES UNDER THIS METAL COVER

SPRAGUE BLUES ATOMS ARE NICE AND AFFORDABLE

OR RUBYS I LOVE

BY THE WAY I TOTALLY APPOLOGIZE FOR THE LENGHTLY POST
JUST TRYIN TO PASS ALONG A IDEA THA I COME ACROSS ALOT
WITH THESE AMPS

[bzimm]

I agree with Blue Lou, when they start poppin fuses like that they usually need to be re-capped. Check the dog house on the underside of the chassis, that is where the caps are. If they are original, they should be replaced.

Surface rust on the transformer is usually only a cosmetic problem, hopefully there is not any rust in the windings. Not sure what I would do with the chassis, probably talk to a local metal shop and see if they can recommend a method of cleaning that up.

[B. Roth]

Thanks for the info on the caps. I'll open it again, to be sure, but the caps all look like the brown Mallorys you described. I wouldn't be suprised if they are original. I'll definately see about replacing them. This amp hasn't been turned on in probably a year and a half. It has just been sitting in my dry garage. Will the caps bleed off over this amount of time? Or will I still need to discharge them?

My guess is I should bleed them off manually just in case. I think I'll just go buy some insulated alligator clips and bleed them off. Thanks so much for the great information. I'm starting to feel a little more optimistic that I might be able to save this amp.

B. Roth

[chuckocaster]

that amp is totally saveable. trust me i've seen worse that have been restored. don't know where you're located, but find a good amp tech if you don't feel comfortable doing it yourself. he can then run an oscilliscope on it and check EVERYTHING. if you don't know of any, find some guys who have tweeds, or serious blues and country guys who play fender. they'll know.

[BLUELOU]

THEM CAPS I MENTIONED YESTERDAY
UNDER THA COVER THEY ARE OL 99% OLD ORIG BROWNIE BATTERY LOOKIN PAPER COVERED MALLORY'S


CHEAPEST WAY TO GET A START ON YOUR SOLUTION IS TO
REPLACE THEM ALL E-MAIL DOUG HOFFMAN OR CALL GERALD WEBER
THE BASSMANS LIKE YOURS THAT I OWN ALL HAVE 6 CAPACITORS
I REPLACE ALL THEM NO MATTER WHA CONDITION THEY LOOK BECAUSE UNLESS YOU JUST BOUGHT THA OL AMP OFF A AMPO TECH OR MUSIC STORE
THEY SHOULD DEFINITELY
ALL BE REPLACED TO BE SAFE AND NOISE FREE
TRUTHFULLY
THIS NO SHIT JUST FACT
RADIO SHACK TUNER SPRAY WORKS WELL IN ALL THE POTITOMETRS VOL TREB AND BASS ON BOTH CHANNELS NORMAL / BASS IT IS CRUDDY RREALLY WHICH IS BAD SO TLC TIME TAKE YOR TIME SKLOWLY AND CAREFULLY REPLACIN COMPONENTS AND ALWAYS UNPLUG THA AMP EVER BEFORE WORKIN ON IT OUTY OF ITS CHASSIS BOX SAFETY IS #1


THEN THA OL AMP PROBABLY WILL FIRE UP BRO FROM YOUR LABOROUS TLC

BUT WHILE REPLACIN THEM 6 CAPS UNDER THE METAL 4X6 DOGHOUSE AND TOTALLY MAKE A DRAWIN
AND VALUE SHEET OF THEM CAPS EXACTLY LIKE
70 MFD 350 VOLTS ETC
BEFORE CUTTIN THEM OUT
DRAW THEM AND THE 5 HOOKUP WIRES 2 TANS AND A DARK BROWN AND A BLUE AND A BOACK EXACTLY
LIKE YOU SEE THEM THIS IS ESSENTIAL YOU DO ONE CAP AT A TIME REALLY THEN ITS LESS CHANCE OF MISTAKES
THESE CAPS LOOK LIKE
C PAPER CPATED BATTERY LOOKIN ONES THINGS POSITIVE+ AND A NEGATIVE-

ALSO GO AND ORDER THE EXACT REPLACENTNT 4 RESISTORS ON THAT BOARD ALSO THESE ARE DIRT CHEAP AT ABOUT .75 CENTS EACH OR SO FROM HOFFMAN
JUSAT AS I MENTIONED IN MY LAST POST
AND I THINK YOUR AMP WLL COME ALIVE EASILY IN ABOUT 1 HR OR SO

IM TAKIN A WILD GUESS BET
ON THIS EPIDEMIC OF 90% OF THE CULPRIT
THAS A GOOD JUDGEMENT IMOP

PLUS WHAT I TOLD YOU WILL NOT HURT YOUR WALLET

NOW !!!!
AS FOR CLEANIN THA CRUD IN THE INSIDE OF AMP UN PLUG IT ALWAYS FORST BEFORE EVER WORKIN ON IT OT ONE

NOW AS FOR ME
I USE OL ARM/HAMMER OR CREST CHEAP GRITTY TOOTHPASTE THE GRITTY CHEAP TYPE PERSONMALLY
AND A DASH OF BAKIN SODA
AND A STIFF OLD TOOTHBRUSH
I GO IN BETWEEN ALL THE WIRES /CIRCUIT BOARD PARTS CAREFULLY
USIN A OL LONG HAIRED 2 INCH PAINT BRUSH

USUALLY I CAN GET A AMP LIKE YOURS
UP AND RUNNING IN A DAY OR 2 DEPENDING
ON MY PARTS ORDER AND MY SUPPLY I HASVE HERE IN PARTS

HERE IS WHAT I DO
FOR MY AMP PARTS CAPACITOR WISE
I ONLY USE 95% TIME KENDRICK AMPS CAPS TO AWWW.KENDRICK-KENDRICK AMPLIFIERS.COM
GERALD WEBER PERSONALLY
SUPPLY ME
WITH I THINK THE HIGHEST TOLERANCE PARTS CAPACITOR WISE
OR POWER RESISTORS/ RESISTORS IMOP FROM MY OWN EXPEIENCES THAS QUALITY '

I RATHER PAY HE LITTLE EXTRA FOR MY QUALITY MATCHED PARTS EVEN RESISTORS ARE BANG ON DEAD HIGHEST QUALITY

I ALSO ORDER BULK POWER TUBE IK TO 470 OHM 5 WATT POWER TUBE RESISTORS (SUGARCUBES ONLY FROM DOUG HOFFMAN AS I LIKE SPEEDY PARTS

I USE PRIORITY SHIPPIN ITS WORTH IT I DONT LIKER TO WAIT FOR PARTS SO I STOCK UP WHEN I RUN LOW ON THESE
HOFFMANAMPS .COM GREAT STUFF DOUG HOFFMAN IS A GREAT GUY FOR PARTS

ALL THESE PARTS REALLY ARE THE REAL STUFF MADE FOR AMPS
SEE IF I GO TO RADIO SHACK OK I CAN BUY 500 ASSORTED RESISTORS THEY WORK FINE BUT FOR ME

I ONLY USE RADIOSHACK FOR SOLDER AND TINY SMALL CERAMIC DISK CAPS I BUY IN BULK

ITS TOTYALLY UP TO YOU .....
JUST PASSIN MY INFO ON TO YOU I LOVE THEM OL BASSMANS

YOUR BASSMAN WAS MADE IN ABOUT LATE 66 OR 67 MORE THAN LIKELY MAYBE ITS A 65 BUT THEM YELLOW CAPS ON THE MAINBOARD LOOK LATER SO IN A GUESTIMATE
MAYBE MAXIMUM IS 68-EARLY 69 STILL SOME CARRIED BA BLACK FACE COVER THATS ALL IT IS REALLY
A MASK UNDER THE CRUD RUST IN THA CHASSIS LOOKIN DOWN NEAR THE LARGE TRANSFORMER POPIN THRU USUALLY THERE IS A STAMP IN BLACK LIKE T352167

FENDER BACK THEN USED UP WHA EVER LEFT OVER PARTS SURPLUS PARTS TO MAKKE AMPS
NO SHIT
SOME EARLY BLACK FACES WERE SILVERFACED ORIGINALS ALSO IN 1968 AND UP ALL SHARED THE SAME WIRING AND CIRCUIT

SOMEWHERE IN 68 THESE SILVERFACES EMERGED
STILL SAME AMP FOR MOST PART
THER MIGHT BE CAPS SOLDERED DIRECTLY ON THE POWER TUBE I CUT THESE OUT IT ROBS AMPS OF TONE WITHOUT THEM ITS A TOTAL NEW BEAST

THEY JUST USED SILVER FACEPLATES IMOP IN 68-CURRENT BUT YOU GO A GOOD AMP ENJOY YOUR ENDEAVOR BRO
YOUR AMP IS PROBABLY IM GUESSIN A LATE 60'S MODEL A 66- 67 OR VERY EARLY 68 STILL LIKE I SID JUST CAUSE CLOR OF FIRST SILVERFACES AS THEY EMERGED THEY USED THE SAME OL CIRCUITRY AS THEIR OLDER COUSINS
MANY TIMES
YOU GOT A GOOD AMP
IF BY SAD CHANCE YOU NEED A TRANNIE FOR THA AMP IT WILL COST YOUJ ANYWHERE FROM $75-150 DEPENDIN WHO YOU USE
I LIKE HOFFMAN FOR THIS
NOW IF I AM AFTER VINTAGER QUALITY NOTE FOR NOTE I USE KENDRICK TRANNIES
THESE SOMETIMES COST WAAAY MORE THABN THE BASSMAN ALP AS A WHOLE BUT THIS IS A EXTREME

PROBABLY THA RE CAP JOB AND THEM 4 LARGE RESISTORS WILL CURE YOUR PROBLEM

GOOD LUCK TAKE YOUR TIME
BE SAFE
SINCERELY
BLUELOU
GODBLESS


THE TLC AND FUN
IS WORTH A POT OF GOLD I CALL IT SATISFFACTION
TO ME I LOVE MESSIN WITH THEM BASSMANS
GODBLESS
SINCERLY
BLUELOU


THERE IS THIS GREAT BOOK THAT IS SOLD BY GERALD WEBER
AT KENDRICKAMPS .COM
ITS CALLED
A DESKTOP REGERENCE OF HIP VINTAGE GUITAR AMPS
IT IS A ASSET TO FENDERHOLICS AND MARSHALL LOVERS

IT WILL REALLY OPEN UP YOURT EYES AND IT IS ABOUT$29.999 FROM KENDRICK DIRECT (512) 932-3130
ITS LOCATED
KENDRICK AMPLIFIERS
ROUTE 2 ,BOX 871
KEMPNER TEXAS 76539
USA...

THERE IS A WEALTH OF INTERESTING INFO IN IT YOU WILL NEBVR GET BORED
HE REALLY BROKE HIS ASS DOIN HIS RESEARCH AND KNOWLEDGE IN ALL ASPECTS OF OLD VINTAGE TUBE AMPS
UP TO SOME CURRENT ONES
PLUS HE HAS A PERSONAL LINE OF KENDRICK AMPLIFIERS

GERALD JUST SELLS SUPER HIGH QUALITY PARTS


THIS IS NOOO SALES PITCH TRUST ME
HE HAS 2 BOOKS THA ARE VERY INSIGHTFUL TO YOUR AMP PROBLEMD THE 2ND ONE OF HIS IS
ITS ALLED
TUBE AMP TALK for theGUITARIST and TECH

I LIKE READING AND IM GOOOF FRIENDS WITH HIM SO HE IS A TONE FREAK
AND A GREAT HUMAN GREAT AMPLIFIER GURU


ASPEN PITTMAN THE TUBE AMP BOOK IS ALSO GREAT

BUT ME PERSONALLY I LIKE THE LAYOUTS THAT THE GERALD WEBER HAS IN THE DESKTOP REFERENCE OF HIP TUBE VINTASGE AMPS
TO ME ITS EASIER TO READ GERALDS THAN >MR
ASPEN PITTMANS BOOK 4TH EDITION....

WHICH IS MORE FOCUSED WITH SCHEMATICS AND TONS OF TECHNOLOGICAL INTERESTING MODS AND LITERATURE TUBE TALK WISE
HE IIS THE MASTERMIND BEHIND GROOVE TUBES { GT} I BELIEVE IT IS A PRICE LESS AND ITS A
TUBE AMPLIFIERS LOVERS GOLDPOT
ASSET FOR ANY AMP TECH
GOOD LUCK
SINCERELY
BLUELOU
GODBLESS
INYOUR CASE
WITH ALLTHA RUST
A GOOD GERALD WEBER SCHEMATIC LAYOUT IS A KEY ASSET TO SOLVIN YOUR AMP PROBLEM AND KNOWLEDGE ASPEN PITTMAN TUBE AMP BOOK 4TH RDITION IS GREAT ALSO


SORRY AGAIN FOR MY LENGHTLY POST
BUT THIS IS ONLY WAY
I KNO HOW TO EXPLAIN THINGS
AND PLEASE EXCUSE MY
CAPS TYPING I ALWAYS TYPE LIKE THIS


BLUELOU

USE GOOD SOLDER AND A GOOD TIPPED SOLDERIN IRON

I GOT A LOAD ADJUSTER THA IS TOTALLY MERCILESS IF ITS OVER ADJUSTED
I USE FOR MY SOLDERIN NEEDS I GO THRU SOLDERIN IRONS EVERY NOW AND THEN ALOT AS I AM GOIN NON STOP FOR HRS
BUT I PUSHA 30 WATT IRON TO 70+WATTS YTO UNSOLDER CRAP FAST I WORK LIKE LIGHTNING WITH THA MUCH HEAT
MY ADJUSTER WILL GO ALL THE WAY TO 200 WATTS OUTPUT WISE

IM FAST REAL FAST / NEAT WHEN USIN THIS AMOUNT OF POTENT HEAT'FOR GROUNDS ON CHASSIS ETC

I GOT SOLDERIN IRON TIP CLEANER AND GOOD TINNING TO GET THINGS ROLLING
AND LOTS OF SPARE IRONS
BE SAFE
HAVE LOTS OF FUN IT IS REWARDING REALLY

I BET YOU ITS YOUR UNDER COVER CAPS BRO!!!!
MAYBE I GUESSED A GOOD GUESS
WHO KONS TILL YOU GET IN THERE AND SEE IT ALL



AND I REALLY APPOLOGIZE FOR MY BAD TYPIN WRITING IT IS LONG BUT LEGITIMATE

[bzimm]

Always bleed the caps just to be safe. Having said that, there is no way they are still retaining voltage if it hasn't been plugged in in a year and a half.

But do it anyway, just in case your roomate plugged it in while you weren't lookin. Plus its cheap insurance.

Lou knows an awful lot about these old bassmans. I will say there are cheaper alternatives than buying your stuff from Kendrick but if you call Gerald and ask for the filter caps for a bassman he will know exactly what you need. The cheaper alternatives require that you know the part number you want.

[B. Roth]

Thanks for the replies everyone. Especially thanks to Bluelou for pointing out Hoffman and Kendrick to me. I'll definately be buying some parts from one/both of them (and I'll tell them you sent me!). I really appreciate all the insight. I really like the way this amp sounded when I first got it...and I'm starting to feel confident that with a little TLC I can get it up and running again. Plus I'll take this as an opportunity to expand my knowledge!

When I get around to fixing the amp I'll be sure to post pics (and maybe a soundclip or two). Thanks again everyone, you've really been a huge help!

B. Roth