50 Watt build sounds weak low volume
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50 Watt build sounds weak low volume
Put together a 50 watt build using the layout below. The output is very low and "weak" sounding. The voltages are:
V 1 2 3 4 5 6 7 8
v1 248 0 3 214 0 2
v2 167 0 1 286 167 168
v3 216 23 37 209 24 37
V 1 2 3 4 5 6 7 8
v1 248 0 3 214 0 2
v2 167 0 1 286 167 168
v3 216 23 37 209 24 37
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- Janglin_Jack
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Re: 50 Watt build sounds weak low volume
That has been my experience with JCM800 design. Thin at low volume. You'll have to read about the tweaks people do to thicken their sound at lower volumes. I think the Tone Lizard had some stuff about it.
I seem to remember the the Kevin Oconner book talked specificaly about the JCM800 style master volume design and it acted as a high pass or low pass filter with the volume rolled down.
Key would be to crank the amp! Or to play at low volume, check into an attenuator or PPIMV and use the preamp master volume and attenuator/PPIMV in tandem.
Mike
I seem to remember the the Kevin Oconner book talked specificaly about the JCM800 style master volume design and it acted as a high pass or low pass filter with the volume rolled down.
Key would be to crank the amp! Or to play at low volume, check into an attenuator or PPIMV and use the preamp master volume and attenuator/PPIMV in tandem.
Mike
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Re: 50 Watt build sounds weak low volume
Worse than that. This thing has no soul at all. Hisses bad with the volume turned up. Something is definetly wrong with the build. I have goone over the board twice and verified all the components. As a starting point anyone have a pic of the cliff jack wiring.
- Janglin_Jack
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Re: 50 Watt build sounds weak low volume
Did you use shielded wiring at the input jacks, etc. Once I converted a plexi build over to a JCM800 style when I was in a Slash kick. I had some issues, but I had to sort out the tone one step at a time and I got some noise at high preamp gain levels.
Mike
Mike
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Re: 50 Watt build sounds weak low volume
I will record a sound clip. It's pretty bad.
Re: 50 Watt build sounds weak low volume
Are the tubes good? Do you have an extra set to try? Try to post some pics. The guys here are really good at spotting things.
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Re: 50 Watt build sounds weak low volume
Tried different tubes. It sounds like an old transistor radio. Going to do a sound clip and a few pics.
- Janglin_Jack
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Re: 50 Watt build sounds weak low volume
O I see, it sounds bad, like something is wrong with the build, not trying to get cranked Marshall tones at bedroom levels. If you can post pics, there are guys here with really good eyes that might spot something.Memphis wrote:Tried different tubes. It sounds like an old transistor radio. Going to do a sound clip and a few pics.
Mike
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Re: 50 Watt build sounds weak low volume
A couple pics. All help is appreciated.
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Re: 50 Watt build sounds weak low volume
Ok, so I made the changes from the following post I found. The next issue is with V1 voltages
http://forum.metroamp.com/viewtopic.php ... k&start=15
1 2 3 4 5 6 7 8
309 0 3 214 0 2
Seems a little high according to the kit instruction voltage chart.
http://forum.metroamp.com/viewtopic.php ... k&start=15
1 2 3 4 5 6 7 8
309 0 3 214 0 2
Seems a little high according to the kit instruction voltage chart.
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Re: 50 Watt build sounds weak low volume
So I made the necessary changes. Now the LO input jack produces nothing. The HI works "ok" . If I remove the ground from the jacks the lo input will work but obvious hum etc.. This thing is driving me crazy. I must have checked it over a hundred times.