Ampeg Trem/Vibrato Issue

[Daver]

I'm working on a '65 Ampeg B18X fliptop. One of the complaints is that the trem sounds funny. It does sound a little sea-sick. I'm not sure if it's normal or not, having not heard this type of trem before. It sounds a little "watery" or Leslie like. I've checked all resistors for correct value and tried replacing tubes. Any ideas? Leaking caps? Is it normal? A link to the scheamtic is below. Thanks.
Dave

http://www.freeinfosociety.com/elect...ew.php?id=1146

[Enzo]

I have one of those, and I haven't had the trem on in decades. it is out in the warehouse now, so I cannot fire it up.

[drewl]

Most of the time the caps in the trem oscillator are leaky and need to be replaced, also the resistors tend to drift up in value also preventing oscillation, however you said you checked those...so I'd start with the caps.
Save them, as you may be able to use them for something else (I've used old vintage caps in guitars)

[Daver]

Thanks guys. I replaced the caps and that didn't change anything. It's oscillating, it just sounds a bit odd. Any other ideas? Maybe it's supposed to sound this way.
Daver

[Pariahscary]

tremolo vs "vibrato"

The b18-x appears to have the "vibrato, " not the "tremolo" feature. It's something of a time/phase shift (perhaps in addition to fluctuating the volume). The earliest appeared on the Echo Twin 2 (see: http://www.ggjaguar.com/et-2-b.htm), and my b12xy allegedly has it, but it needs an overhaul and vibrato is not working. Your schematic indicates a VM-1 module in the circuit as well, which is a later development for the same concept. I haven't heard what it should sound like, or if it's a true vibrato or not, but it's different than typical amplitude-modulation tremolo. Some later Geminis (like the Gemini IV I think) had the VM-1, whereas most G-12's and G-15's (as well as the RRII and reverbojet) have the regular tremolo, using a TM-1 module. Some even have a switch that selects one or the other.

[Daver]

Yes, I've come to the conclusion that it's vibrato and that's the way it's supposed to sound. There is a mention of it in the Ampeg book I have. So I guess it's case closed. Thanks.
Dave