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Does anyone here build amps as a hobby? The reason I ask is because I would like this amp built as low buck as possible. It has two 6L6's and a 5U4, but no preamp. I also have two small radio/hifi amps with lots of tube sockets and such for parts. Anyone interested in the challenge?
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Hi, Greetings and welcome to the board.
On this site you'll find hundreds of enthusiastic hobbiests, myself included.
Your post is kind of open, and a bit vauge.
Just my opinion here,so don't take any offense because none is intended, fill out your profile completley. Who knows you might be just a few blocks from someone else here.
Second lets get to know who you are and what kind of experience you have. As many will no doubt remind you, tube amplifiers can be VERY dangerous. They contain lethal voltages and many EXPERIENCED craftsmen here may shy away from replying untill they know where your skills are.
It doesn't matter if you havent picked up a soldering iron before or perhaps you've a masters degree in electronics.
But if these folks don't know at what level to comunicate to you, they will likely err on the side of caution and not offer much help.
I myself am pretty new to the tube amp world and have built a 5E3 Deluxe, converted a few odd amplifiers into guitar amps and I'm currently building an 18 watt marshall, a 35 watt frakenstien of a 5E5 Pro with a Black Faced style preamp and tone stack and a simple 10 watt class AB1 bedroom amp.
Other things people on here may like to know is if you are a guitar player, and what kind of guitars you own and maybe what genre of music you play. are you a harp player? vocalist? etc..
Those are the sort of things that would heavily influence the type of amp you would want to build. Your organ chassis is a good score full of many things you'll need to build an amp on a budget.
So fill out your profile, introduce yourself properly and discribe what you would like to acomplish (what style amp you would like to build).
Do us a favor too, don't run off, stick around, read some of the old posts and enjoy yourself here. There is a wonderful resorse of knowledge here for you to learn from.
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Dito to what Stingray said. Read as much as you can , dont feel stupid for asking a what you may think is a simple question. Remember their are no wrong questions just wrong answers. Dont limit yourself to just one forum, their are alot of good forums out there including this one. Weber speakers has a nice forum with a lot of friendly people. I have done a couple amp conversions with old PA amps since i joined this sight as well as other sights. Be patient and have fun.
BaddogComment
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Hi! My name is Gayler and I am a want to be musician. I have a 1965 hagstrom Viking. I like blues and classic/ hard rockand most other kinds of music.I would like to build something fenderish. Nothing too loud that will breakup nice at lower volumes. I am about half way through with a champ build, so I can solder. I don't have much experiance reading schematics. I also have a pair of P10Q's from the same organ, one in good shape and one needs to be reconed.Originally posted by stingray_65 View PostComment
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ALL RIGHT!
ya didn't run away good for all us!
these next few questions are very important
do you know the parts and places in an amp that will hurt you?
do you know how to discharge a filter cap?
can you read a VOM? (volt-ohm-meter)
do you own a VOM? what are its highest and lowest ranges?
so you can solder! good! it is a life long skill that will serve you in many ways,
but do you know how to unsolder? you will by time you'r done deconstructing that Lowerey chassis
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YesOriginally posted by stingray_65 View PostALL RIGHT!
ya didn't run away good for all us!
these next few questions are very important
do you know the parts and places in an amp that will hurt you? Most likely the filter caps.
do you know how to discharge a filter cap? I have read how to do it with a resisor but have never done it.
can you read a VOM? (volt-ohm-meter) Yes
do you own a VOM? what are its highest and lowest ranges?Yes I have two I was a Ford sevice tech for five years. One is 600V/20V, can't remember the other one
so you can solder! good! it is a life long skill that will serve you in many ways,
but do you know how to unsolder? you will by time you'r done deconstructing that Lowerey chassisComment
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AWRIGHT Gaylun from Kansas!
very cool chassis! nice and simple easy to work with, and it has a 9 pin socket for your preamp, two would have been nicer, but hey this is a budget build right?
well first thing I would do find some lumber and nail up a cradle so you can flip this chassis with its guts up and the tubes not touching anything. nothing fancy, just sturdy
have you tried to plug this in yet?
if yes then be aware of all your shock hazzards ( that big silver cap can)
you'll want to pull those 6l6's leave the 5U4 in and take some readings to know what voltages you have available to work with in your design
with your meter set to it's highest DC scale measure from the different lugs on that big cap can to chassis ground and write the voltages down
you'll also want to pull the 5U4 and the measure pins 4 and 6 to ground, only this time use the AC scale at its highest setting
with your meter still on AC select a scale for about 20V and put you meter leads direcly on pins 1 and 8 and verify that there is 5VAC there and not too much higher, write this measurement down too
lastly check your heater leads. they will be pins 2 and 7 on the 6L6 sockets. measure them the same way as you did pins 1 and 8 on the 5U4
unplug and discharge your power caps at this time
don't just spark a screw driver across the terminals, yeah the big blue snap is cool, but using a discharge wand is the way to go.
you now have the basic parameters of the amp you can build in this chassis with the basic parts you have there.
you have the power supply voltages
3 octal sockets
one for rectification two for power pentodes
a nine pin socket for a 12ax7 preamp and phase inverter
an output tranny designed for 6L6's in push pull.
is there a harbor frieght near you?
they sell the most inexpensive step drill that has the correct diameters to add sockets in a chassis.
at least one more 9 pin socket would give you some options to add some gain and tone controls.Comment
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Yes I have pluged it in. It has no power switch as it was mounted on the organ but I jumpered the terminals for power and the tubes did light up.Comment
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Also the amp has one 1/4 inch jack that was not connected to the organ. would this be an input? there is a round four pin socket on the side. I think this is the speaker out. I have a solid state amp with line out, can this be plugged into the amp as a preamp for testing?Last edited by tboy; 05-01-2009, 08:04 AM.Comment
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I see that their is a mini nine pin socket to the left of the 6l6's. Im asuming that it had a 12ax7,12at7 or 12au7. That is the phase inverter section. so you will need a tube for that section in order to try the amp-.
"Also the amp has one 1/4 inch jack that was not connected to the organ. would this be an input? there is a round four pin socket on the side. I think this is the speaker out. I have a solid state amp with line out, can this be plugged into the amp as a preamp for testing? " Depends if that is an input or an speaker output jack. Find out where the wire goes after it leaves the 1/4" jack. If it goes to the phase inverter ( 12ax7,12at7 or 12au7 socket ) it should work . If it goes to the output transformer ( smaller of the two transformers)its a speaker jack. Make sure you have a speaker or speaker load conected to the amp if you power it up for any length of time.
If i had the amp i would gut it and install an old bassman schematic in the amp. Do some studying and have at it, My first amp i built was an old bogen phono amp that i converted to a fender deluxe and to my amazement it worked . I found the schematic at http://www.schematicheaven.com/index_HTML.htm
The schematic had the layout for the parts so all i had to do was buy the parts and connect the dots. You just need to be careful and take your time. .
BaddogComment
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gotta subscribe to this thread...
I'm going through a very similar sort of thing with a Wurlitzer 420 amp, though I have more stuff sticking out of it, and less knowledge than the OP.
Here's a pic!
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Two years ago i didnt know anything about building amps and i still know very little compared to the guys on this sight. But i can now build and amp that sounds good and looks half ways decent. Do some studying , find a friend who knows anything about electricity, buy a book on tube guitar amp building( if you ahve the money). I was lucky enough to work at a local university and befiended a electronics professor who helped alot. Check out http://www.tedsforums.com/forum/ for help and advice. It can get frustrating at times but be carefull it can be addicting buiding amps. Always be carefull because of the high voltages floating around in the amp weather its on or off.
BaddogComment
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hello i am trying to learn how to power up lowrey 6l6 amp how do i jump this amp from amphenol socket someone help please iam new to this with organ amps thanks for any help virgilvdog2@aol.comComment
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