Record Fades In at Start

Q&A about all types of jukeboxes: Wurlitzer, Seeburg, Rock-Ola, AMI, and more.



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nicfic
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Location: Detroit Michigan USA

Record Fades In at Start

by nicfic » Sun Oct 19, 2014 9:37 pm

My 1965 Seeburg Electra starts each new selection at a lower volume and then builds to full volume after about 4 seconds. What's the fix or is this suppose to happen?


Ron Rich
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Re: Record Fades In at Start

by Ron Rich » Sun Oct 19, 2014 9:54 pm

This is normal, due to the AVC amplifier circuit. It is somewhat adjustable, depending on the needle landing adjustment, which needles are being used, and the 3M-11 contact adjustment. Ron Rich


Rob-NYC
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Re: Record Fades In at Start

by Rob-NYC » Mon Oct 20, 2014 2:17 am

nicfic wrote:My 1965 Seeburg Electra starts each new selection at a lower volume and then builds to full volume after about 4 seconds. What's the fix or is this suppose to happen?


A Ron mentioned that fade-up is normal. However, if you are using non-Pickering styli the chances are that the output from the cart is low and thus the amp's AGC will have to raise it's gain to attempt to bring the record up to level. The AGC is given a squelch voltage during muting and handling, the idea is to have the circuit assume a 'loud" record and not overshoot and blast at the beginning, then back-off a second or so later. I'm simplifying it, but that is the essence of what is happening.

That amplifier is fifty years old and should be rebuilt for safe operation. While rebuilding there are simple mods that can increase the preamp gain so that low-output copy styli don't take so long to level. I do -not- recommend disabling the AGC, this can lead to distortion and annoying level differences.

Rob-NYC
"If we believe absurdities, we shall commit atrocities" -- Voltaire

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