Maintenance for Tube Preamps

Generally speaking, if something is wrong you will most likely be able to hear it. The problem with proactive maintenance (especially with vintage gear) is that you can change the tonal quality - and not necessarily for the better.

Contact cleaning is fine. I would advise against changing/replacing any internal parts other than tubes if the preamp is working fine.

Cleaning connections on a regular basis is a good practice, but I advise against products that leave a film because over time it can get messy and cause problems. A good electrical contact cleaner that leaves no film is your best bet.

Thanks to all who responded - good advice! A bit of contact cleaning is probably a worthwhile thing to do.

I would stay away from Cramolin. It does tend to keep cleaning even when you don't want it to and can leave crud behind. I use pro gold but again if it isn't broke don't fix it. Changes can be made sonically to the preamp by replacing coupling caps etc.