Alembic F2B troubleshooting

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Alembic F2B troubleshooting

Postby Rusty the Scoob » Mon Mar 04, 2013 9:00 am

Hogan offered me a vintage F2B at a great price so I jumped on it! :cool: So far I like the tone and while I miss a few of the modern features (mostly a tuner-out and DI) it's a nice item to have.

One issue though - it seems that when I drive it a little hard it builds up a sort of static charge or something, so that every so often a really loud "Blat!" comes out of the speaker. I turned my power amp down and the preamp up and it got a lot better - the "Blat!"s were less loud but didn't go away.



My signal path was Fender P-bass with EMG pickup and onboard EQ into a Nady line-mixer, to either channel of the F2B (I tried both, both had the issue) and then to my Crown XLS2500, into a 1x15" Eden cab. I used the "Mono" output of the preamp for my rack tuner.
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Re: Alembic F2B troubleshooting

Postby zambiland » Wed Mar 06, 2013 3:26 pm

Rusty the Scoob wrote:Hogan offered me a vintage F2B at a great price so I jumped on it! :cool: So far I like the tone and while I miss a few of the modern features (mostly a tuner-out and DI) it's a nice item to have.

One issue though - it seems that when I drive it a little hard it builds up a sort of static charge or something, so that every so often a really loud "Blat!" comes out of the speaker. I turned my power amp down and the preamp up and it got a lot better - the "Blat!"s were less loud but didn't go away.



My signal path was Fender P-bass with EMG pickup and onboard EQ into a Nady line-mixer, to either channel of the F2B (I tried both, both had the issue) and then to my Crown XLS2500, into a 1x15" Eden cab. I used the "Mono" output of the preamp for my rack tuner.


Hm, does it do it with both channels? That's odd behavior. One thing I would check is the health of the filter caps. On the very old units, they are held up by foam and when that dissolves after a few decades, it can make the caps' connections tenuous, so maybe you've got a loose cap and when it makes a connection, it does this. Definitely bring it up at the Alembic forum.
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