Caps off, please...
Back to the start of the thread - you built a Pacific preamp and experienced a noise problem. Noise or hum? I suspect it was hum, though you can correct me on that if you wish. Running the preamp with a raw rectified and filtered supply may cause some hum feedthrough, but it's best to try a few things first before trying to build an exotic regulator that may only cure part of the problem. I would first try a simple LM317 regulator, or even buy or borrow a good bench supply and power up the preamp. Even a simple zener shunt regulator would serve to knock the hum off your power supply line. Does the hum go away when a regulated supply is used? Yes? If so, I would kick back and enjoy the preamp for awhile and get used to its sonic palette before trying something else. If you're not used to the sound of your preamp, it may be hard to tell if a change is significant.
No? If not, then you want to first check the ground connection between TT and preamp. This should go to a single point ground that is shared with the one for the preamp. If this ground is just connected to the chassis any old way, you may be setting yourself up for a ground loop. The input connectors should also be isolated from the chassis, but connected to that single point ground. The preamp should be in a box for critical listening, as it is a high gain circuit, and it's easy to get pickup, as power line noise is just about everywhere. If necessary, you can move the power supply to a separate enclosure if hum pickup seems to be a problem.
These are the obvious things to try first - I would next look at the layout. A simple circuit like this can be done compactly, with small loop areas. This reduces stray inductance and also reduces the chance for noise pickup.
As far as the Sulzer regulator is concerned - if you're only starting with 32V, the drops in the two stages are going to knock your output voltage capability down quite a bit. I would think you'd have 24V or less when you are finished, especially as you want to ensure that there is sufficient voltage across each regulator stage so that it really works as a regulator. If you're intent on using the Sulzer regulator at some time, I would start with a 5534 before trying something more exotic. Mistakes will be far less costly. After you get the thing running with a 5534, you can then swap opamps around.
Back to the start of the thread - you built a Pacific preamp and experienced a noise problem. Noise or hum? I suspect it was hum, though you can correct me on that if you wish. Running the preamp with a raw rectified and filtered supply may cause some hum feedthrough, but it's best to try a few things first before trying to build an exotic regulator that may only cure part of the problem. I would first try a simple LM317 regulator, or even buy or borrow a good bench supply and power up the preamp. Even a simple zener shunt regulator would serve to knock the hum off your power supply line. Does the hum go away when a regulated supply is used? Yes? If so, I would kick back and enjoy the preamp for awhile and get used to its sonic palette before trying something else. If you're not used to the sound of your preamp, it may be hard to tell if a change is significant.
No? If not, then you want to first check the ground connection between TT and preamp. This should go to a single point ground that is shared with the one for the preamp. If this ground is just connected to the chassis any old way, you may be setting yourself up for a ground loop. The input connectors should also be isolated from the chassis, but connected to that single point ground. The preamp should be in a box for critical listening, as it is a high gain circuit, and it's easy to get pickup, as power line noise is just about everywhere. If necessary, you can move the power supply to a separate enclosure if hum pickup seems to be a problem.
These are the obvious things to try first - I would next look at the layout. A simple circuit like this can be done compactly, with small loop areas. This reduces stray inductance and also reduces the chance for noise pickup.
As far as the Sulzer regulator is concerned - if you're only starting with 32V, the drops in the two stages are going to knock your output voltage capability down quite a bit. I would think you'd have 24V or less when you are finished, especially as you want to ensure that there is sufficient voltage across each regulator stage so that it really works as a regulator. If you're intent on using the Sulzer regulator at some time, I would start with a 5534 before trying something more exotic. Mistakes will be far less costly. After you get the thing running with a 5534, you can then swap opamps around.
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