When playing my Express the other day I noticed that if I turn all knobs to 10 then the volume drops a bit. I also confirmed this by measuring the wattage and found that it dropped by about 3/4W when on max. I'm never going to play the amp that way but has anyone else had this?
Amazingly this gain machine still sounds pretty good with everything maxed out!
Express - Volume decreases on max
Moderators: pompeiisneaks, Colossal
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Littlewyan
- Posts: 1917
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- Location: UK
Re: Express - Volume decreases on max
Sounds like an oscillation issue.
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Littlewyan
- Posts: 1917
- Joined: Thu Sep 12, 2013 6:50 pm
- Location: UK
Re: Express - Volume decreases on max
I'll have to experiment. I'll turn the lights off then turn the volume up with nothing plugged in and see if the EL34s light up. I'm sure they don't if I just turn the volume up, I think its just when everything is on full.
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Reeltarded
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Re: Express - Volume decreases on max
turn everything to ten and probe all the wipers for drops WITH THE AMP OFF
hehe
Find the pots that don't change it and focus on the ones that do. I thinkit's in the tones.
If not ultrasonics, then this. Sorry, I was never good at latin.. ergo proctologist something.
hehe
Find the pots that don't change it and focus on the ones that do. I thinkit's in the tones.
If not ultrasonics, then this. Sorry, I was never good at latin.. ergo proctologist something.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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Littlewyan
- Posts: 1917
- Joined: Thu Sep 12, 2013 6:50 pm
- Location: UK
Re: Express - Volume decreases on max
I had a quick poke around. Problem is I have 2 cordless phone sets and a router on my desk -_-. So I got loads of interference whilst I was testing which kinda ruined the test and made it pointless.
I do still have the buss bar soldered to the back of the pots which I no longer need since I fitted proper ground points when I rebuilt the amp earlier this year. I've left it in because I didn't think it was hurting anything but might remove it at some point. Also the treble wire could be shortened a bit which may help things. Here are some pics to show the inside. Let me know if you want more.
I do still have the buss bar soldered to the back of the pots which I no longer need since I fitted proper ground points when I rebuilt the amp earlier this year. I've left it in because I didn't think it was hurting anything but might remove it at some point. Also the treble wire could be shortened a bit which may help things. Here are some pics to show the inside. Let me know if you want more.
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Re: Express - Volume decreases on max
Check for an ON/OFF switch. Failing that, unplug 'em, and enjoy the solitude.Littlewyan wrote:I had a quick poke around. Problem is I have 2 cordless phone sets and a router on my desk -_-. So I got loads of interference whilst I was testing which kinda ruined the test and made it pointless.
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Littlewyan
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- Joined: Thu Sep 12, 2013 6:50 pm
- Location: UK
Re: Express - Volume decreases on max
Couldn't at the time. Everyone was home. I might get a chance this weekend though to unplug everything.
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Littlewyan
- Posts: 1917
- Joined: Thu Sep 12, 2013 6:50 pm
- Location: UK
Re: Express - Volume decreases on max
I'll add to this as I don't like leaving an incomplete thread. Basically I think the issue is my V1 EH12AX7 hums a lot with the volume on full which is already driving the Output Valves pretty hard. It decrease in volume is no where near as much with other valves.
Still the EH12AX7 should be dead quiet as it has a spiral filament heater. But I don't think there is an issue with the amp as other valves don't do this :S. Odd.
Still the EH12AX7 should be dead quiet as it has a spiral filament heater. But I don't think there is an issue with the amp as other valves don't do this :S. Odd.