Webb 614e Reverb tank

Alan Murphy · From: N Ireland

Does anyone know the correct spring reverb for an old Webb 6-14E amp, probably about 1978 Thanks Alan

Ken Fox · From: Nashville GA USA

From Tom Bradshaw a while back

I've learned that the pre-1980 amps (which is what your amp is) were fitted with at least three Accutronic (brand), 2-spring reverb tanks: the 4FB3A1B and the 4FB2A1B. At the very end of that production series, the short 3-spring 4BB2A1B. The current Webbs (built from 1994 to the present), used the shorter Accutronic brand with 3 springs, the ABB2A1B. ...Tom

Ken Fox · From: Nashville GA USA

My comments on that same post

Tom nailed it on the head about the tanks. I have seen a lot of Webb amps on my bench in the last year or so and have learned a lot more about the reverb system in the amp.

The reverb drive of the older amps was a single transistor operated in Class A mode and used the large reverb tank. The larger tanks had a higher input impedance (in the range of 1475 ohms or so).

The newer amps used a push pull transistor circuit and take the small tank (8BB2A1B). The tank has a low impedance input of 150 ohms. The older amps do not like the low Z input of that tank at all! Best to use the long tank with the old amps as it is a higher input impedance.

Kevin Mincke · From: Farmington, MN (Twin Cities-South Metro) USA

I went through several tanks trying to remedy the problem and Ken told me that if there is an open ground somewhere the reverb would not work or be over the top out of control. I sent my preamp board to him and sure enough, exactly as he stated. I was able to put the old reverb (accutronics or Gibbs) don’t recall and it worked like a champ. I tightened up the four small suspension springs as over time the pan was hanging low and touching the bottom. I had put a MOD 4FB3A1B in it and it worked fine as well. Yes, much higher dc to drive reverb circuit than others. I actually believe the pan was used from maybe an organ or acquired from stock off the 60’s No number stamped such as Accutronics used but rather four digit 6713 as I recall.

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