5e3 problem - low output!

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vibratoking
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Re: 5e3 problem - low output!

Post by vibratoking »

I am guessing this is some kind of wiring problem. Don't just try to look at it, it will always look right to you. Just like it did when you assembled it. Get a schematic and/or a layout. Systematically go through the amp and look at every connection. As you examine each single connection and painstakingly verify it's attachment points, use a highlighter to highlight that connection on the schematic and layout. In this way you can verify that everything in the drawings is actually connected. Anything not highlighted in the drawings will cause you to think in detail about that section. Take nothing for granted. We are all predisposed to see things a certain way, which may or may not be the right way. In my experience, once a person sees a bad connection as being good, it is very likely that he will continue see it that same way, until he forces himself back to the basics. Get the drawings, verify the connections, highlight them. Anything not highlighted is a potential problem. You have come a long way with your soldering. Roll up your sleeves and be thorough. Best of luck.
ben85
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Re: 5e3 problem - low output!

Post by ben85 »

thank you both!i've checke the wires maybe a thousand times,but i'll check them again with highlighting!i've rated every resistor(all fine)and every wire to verify it's resistance is 0 Ohms.i'll check again and update,thank you!

when i turn on the standby switch,yes there is a little hum going out the speaker,but not loud.it's like a reasonable hum that ensures that the machine works.
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cbass
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Re: 5e3 problem - low output!

Post by cbass »

make sure your input jacks are wired correctly.I couldn't quit make it out on the pic you posted.

You are probaly ok without the light bulb limiter at this point but still a must have if you are going to build amps
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cbass
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Re: 5e3 problem - low output!

Post by cbass »

Reeltarded wrote:How good would you be at metering everything? Not so much to get voltages at first, but if you start on an AC setting with the amp turned down and over at the output tubes just using the probe to find the latest place in the circuit that seems to be passing good signal?

Does that make any sense? For instance you get louder tick fritter and pop over at the output, then working back towards the input the probing noise drops dramatically.. it's a way of getting to know the amp without being exacting in the details. That is how I start troubleshooting similar problems.
What reeltarded suggested is a good idea.Set your meter to AC With the black probe attached to ground.Touch the other probe to pin 2 or pin 7 on your preamp tubes.You should get a hum and noise like when you touch the tip of a cable plugged into an amp..No noise then your signal isn't going to pass that point.Please be careful

Does your hum/hiss increase when you turn the volume up?It should
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cbass
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Re: 5e3 problem - low output!

Post by cbass »

Anyone else wanna jump in here.I am not very good at explaining stuff.I'm bad dyslexic. My words and thoughts don't correlate.
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alvarezh
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Re: 5e3 problem - low output!

Post by alvarezh »

If I am not mistaken, Reel wants you to check on the plate pins NOT the heaters (pins 2 & 7), that would be pin 3 on the 6V6s, 1 & 6 on the 12a_7s. The pops you should hear tells you the circuit is good from the point you probe, all the way to the speaker.

All the best.
Horacio

Play in tune and B#!
ben85
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Re: 5e3 problem - low output!

Post by ben85 »

alvarezh, i wrote in my first post i think,that i've already rated pins 1 and 6 on the preamp tubes and these rates are 162v and 174v at pins 1 and 202v and 166v at pins 6(v1 & v2).Also, 346v at pins 3 at the 6V6 (with tubes on)

cbass,i'll check pin 2 and 7 tomorrow and post photos too.thank you!
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alvarezh
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Re: 5e3 problem - low output!

Post by alvarezh »

Ben, check Reeltarded's post on the previous page (page 3) again. He's giving you a procedure to check the operation of the amp at different stages on the signal path, that has nothing to do with measuring voltages.

All the best.
Horacio

Play in tune and B#!
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alvarezh
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Re: 5e3 problem - low output!

Post by alvarezh »

Please re-read my initial post again. Pins 2 and 7 on the 6V6 are heater also called filament voltages, you already measured those, haven't you?

What we are discussing at this moment is a procedure Reeltarded proposed you to do in order to find out if the amp's signal path (think of it as the path the guitar's signal follows) is working properly as it travels through the amp.

I gather you're not fully trained in the English language, so I kindly suggest you get help from someone who is. Not been able to understand the language and having limited knowledge on guitar amps will make troubleshooting your amp very difficult. You must understand fully what is being recommended for you to do otherwise you will be loosing your time reading what the guys post in trying to help you.

Again, the troubleshooting procedure Reeltarded posted is excellent, re-read, try to understand and execute it. Then, report back on your findings.

Good luck and best wishes.
Horacio

Play in tune and B#!
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cbass
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Re: 5e3 problem - low output!

Post by cbass »

I was talking about pins 2 and 7 on the 12ax7's Probing them should cause some buzz That will increase if you turn up the volume.I suppose probing the plates and listening for the pop would accomplish the same thing.I was just trying to suggest the safest method I could think of.

I'm gonna let others suggest troubleshooting methods.I'm just not very good at explaining things.
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alvarezh
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Re: 5e3 problem - low output!

Post by alvarezh »

Understood cbass.

Have a good weekend.
Horacio

Play in tune and B#!
tsutt
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Re: 5e3 problem - low output!

Post by tsutt »

ben85 wrote:thank you both!i've checke the wires maybe a thousand times,but i'll check them again with highlighting!i've rated every resistor(all fine)and every wire to verify it's resistance is 0 Ohms.i'll check again and update,thank you!

when i turn on the standby switch,yes there is a little hum going out the speaker,but not loud.it's like a reasonable hum that ensures that the machine works.
The point here is to check the wire connection locations not the resistance of the wire. make every wire connects to the correct spot it is supposed to go. i know i have done it wrong. at all components, tubes, pots, board make sure to double check everything.
ben85
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Re: 5e3 problem - low output!

Post by ben85 »

tsutt,i said this,because if the wire's resistance is 0 from joint to joint,the connection is correct,right?otherwise, the resistance it's infinite.anyway,i checked and highlighted the schematic simultaneously and my wiring is correct.so,i'm gonna do what reeltarded suggested me,but i have a question-explanation here.i check this with the tubes,speaker on and amp on, from the input jack to the speaker,right?the volume pot full?
tsutt
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Re: 5e3 problem - low output!

Post by tsutt »

REEL will have to explain the method he mentions, i'm not sure exactly what he's getting at either. I am fairly new to all of this myself.
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NickC
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Re: 5e3 problem - low output!

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