Low volume issue
Moderators: pompeiisneaks, Colossal
Low volume issue
I'm having a strange issue with low volume in a 183 d style build and was hoping someone might have some insight. Basically all my controls work as they should but the volume level at Max volume is low, like 2-3 in loudness. Channels switch, and the issue is the same wether in clean or drive. Tried swapping tubes and no difference. All my voltages are spot on. Anyone have any suggestions as to what I can test? It's weird, the tone from the amp sounds like it should, just low volume...thanks for any advice.
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pompeiisneaks
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Re: Low volume issue
Lots of things could be going on
1. you could have a bad tube
2. you could have a weak connection that's basically got high resistance causing poor signal transmission
or it could be many more i'm not thinking of.
I'd try and see if you can put something that's preamp level into the power amp in jack and see if you get high signal, if so, the problem's in the preamp, if not, it's in the power stage, that at least will help you figure out where it's coming from in some section of the amp.
If you have a scope, input a sine wave from a phone app or a sig gen and trace where each stage's input vs output is, and see where it's 'dropping out'. If you don't you could build a signal tracer and trace it that way.
~Phil
1. you could have a bad tube
2. you could have a weak connection that's basically got high resistance causing poor signal transmission
or it could be many more i'm not thinking of.
I'd try and see if you can put something that's preamp level into the power amp in jack and see if you get high signal, if so, the problem's in the preamp, if not, it's in the power stage, that at least will help you figure out where it's coming from in some section of the amp.
If you have a scope, input a sine wave from a phone app or a sig gen and trace where each stage's input vs output is, and see where it's 'dropping out'. If you don't you could build a signal tracer and trace it that way.
~Phil
tUber Nerd!
Re: Low volume issue
I have another working build, could I hook the "pre amp out " from that to the power amp input of my defunct amp for testing purposes?
I don't have a scope anymore, but I agree this might be best diagnosed with one. I'll double check my connections too. Thanks
I don't have a scope anymore, but I agree this might be best diagnosed with one. I'll double check my connections too. Thanks
Re: Low volume issue
Yes, plug any sound source into the FX return and see how it sounds. That effectively divides the problem into preamp vs power amp.
I build and repair tube amps. http://amps.monkeymatic.com
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Stevem
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Re: Low volume issue
How much current are your output tube(s) pulling at max volume?
Is the output stage class A?
Is your power supply sagging at max volume , if not then your output tube(s) is likely not pulling much more current then at idle.
This could be from not enough drive signal, or the output stage not being able to source enough current thru it's connections.
Just something to chew on here!
Is the output stage class A?
Is your power supply sagging at max volume , if not then your output tube(s) is likely not pulling much more current then at idle.
This could be from not enough drive signal, or the output stage not being able to source enough current thru it's connections.
Just something to chew on here!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Low volume issue
Pre amp is fine running through other amp. Problem is in the power stage. I'll recheck my connections. And test some more. Thanks for helping me narrow it down.