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Topic: Trem comes on slow! |
Marc Jenkins
From:
Victoria, British Columbia, Canada
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Posted 8 Sep 2013 9:51 pm |
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I no longer really know what to call my guitar amp. It started as a 6L6-equipped Princeton Reverb clone, with deluxe transformers. Then I changed the tone stack to tweed-style, lowered some voltages closer to 5E3 specs, and cathode biased, then raised the voltages back up.
The trem was moved over to the phase inverter. Other than some low end throb I intend to filter out, my only complaint is that when turning on via te foot switch, it takes about 3 seconds to reach full intensity. I liked the short ramping effect of the previous bias-vary trem, but this is a little silly.
Any ideas or suggestions? |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 8 Sep 2013 10:35 pm
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Short of suggesting a buffer on the oscillator we need a schematic to suggest with... exactly how did you put the tremelo on the PI? What kind of PI? Long-tail? How do the DC voltages change when applying tremelo?
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Too much junk to list... always getting more. |
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Marc Jenkins
From:
Victoria, British Columbia, Canada
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Posted 9 Sep 2013 6:19 am
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| Fair enough. Will draw up schematic when I can. |
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Clyde Mattocks
From:
Kinston, North Carolina, USA
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Posted 9 Sep 2013 6:32 am
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I have a similar issue in a mid 70's Deluxe Reverb. The tremelo wasn't working at all and my tech replaced the opto thingy. It worked great for about six months and now it works but takes about ten seconds to come on the first time of the night, then about three seconds after that. Tube??
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LeGrande II, Nash. 112, Fender Twin Tone Master, Session 400, Harlow Dobro, R.Q.Jones Dobro |
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Tim Marcus
From:
San Francisco, CA
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Posted 9 Sep 2013 7:45 am
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when you have the tremolo switched off, traditionally the oscillation takes a few cycles to come back. The values in the tremolo circuit may have drifted a little making the oscillation weaker, thus taking more time to ramp up.
tremolo can be tricky - you might want to spend some time playing with cap values and resistor values to get it perfect. In my Milkman amps, the tremolo was done almost entirely by ear to get it perfect in an amp with cathode bias. I ended up wiggling the grids on the output tubes but you can also wiggle the grid of a preamp stage if you don't mind a little thump
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Milkmansound.com |
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