Okay, hopefully this diagram helps, this is for the EHX positive tip supply.

I’ve added a 1N4002 diode on the drawing too, if you add this in if you make a mistake with the wiring or plug in a negative tip supply in the future by mistake the circuit will be protected.

You can remove the 3 original transformer wires as you aren’t using it anymore.

I agree replacing all the electros & tants is a reasonable course of action, they’re nearly 40 years old already so saves you a job down the line but I hate to think of the PCB and active parts being replaced for no reason and ruining its originality, while it probably is one of the opamps you could easily pin point which one and then keep it as stock as possible, especially as those old boards can be a bit flimsy so replacing that many parts might take its toll.

If you take the voltages of all the opamps and post them i’ll be able to tell you where the problem is, you don’t have to remove anything to do that.

Page 3 here has a readable and correct schematic to help (albeit with an additional output booster circuit and vibe switch) http://lectric-fx.com/wp-content/uploads/2016/07/Bloodstone_V.1.1.pdf

Hi Paul,

No a buzzer wont be any good, the point of the audio probe is that you can hear exactly what is happening to the signal at different points in the circuit, so if you probed the input transistor base and there was nothing or a very weak signal you could assume there’s a bad connection from the input jack or a short somewhere and if you probed the second transistors collector and there was no boosting happening you’d know the issue was between the transistors etc.

And yes the 9V battery needs to be installed and the circuit switched on with some kind of signal being put through the circuit (strumming a guitar, a CD player or whatever) when probing.

Okay, next step then is an audio probe, here is a guide to building one and how to use one, it’s quite simple and should get to the bottom of where the problem is.

http://www.diystompboxes.com/wiki/index.php?title=Debugging

And the schematic to work from;

Test at the base and collector of each transistor and describe what you hear.

I thought the good vibes was optical based, not BBD?

There is an 78L15 regulator on board which regulates the voltage to 15V but it needs some extra voltage (about 1.7V if I recall correctly) to do its job and 18V is a fairly standard supply voltage that meets that criteria.

Try powering just the B9 on its own and see if the noise remains.

How are you powering it? The B9 needs an isolated supply, sounds like you might have it on a chain.