Phone preamp question

These units have been heavily modified by many but the biggest bang for your buck is a better tube, then the power supply.

Yes, that’s next. The 12ax7 that comes with it is a ’Ruby’, whomever the heck makes that, which I’m certain can be improved upon. Going to get an nos low microphonics Telefunken from a guy close to me here in Connecticut. Too bad it’s not a 12au7 in the Bellari as I’ve got many really nice nos ones already.

@holmz , good idea! I’ll switch them out one of these nights and see if I can hear a difference. Just keep in mind we’re not dealing with real high end stuff here. I'll also report back on the tube switch out.

High quality audio is always directly associated with high quality power supplies.

It's a very general statement. No offense intended, but I'm not sure a bare bones $250 Bellari phono preamp qualifies as high quality. In this case, switching out power supplies will probably not reveal much. Tube rolling in this scenario would probably make more sense when trying to upgrade audio performance. I've personally always loved Telefunken's myself. 

I am glad you posted this, I did not know Bellari was made in USA. 

Glad to hear about it, just sent info to a friend.

Ughhh! There is no such thing as a "passive preamp". The two words are mutually exclusive, like "military intelligence" or "Geoff Kate". 

@dpop 

High quality audio is always directly associated with high quality power supplies.

a very general statement. No offense intended, but I'm not sure a bare bones $250 Bellari phono preamp qualifies as high quality. In this case, switching out power supplies will probably not reveal much. ...

I'm in agreement with the notion that a wall wart will almost always be inferior to a well-designed power supply.

In my case I've been using the similarity priced NAD PP2 phono preamp. There is substantial ripple voltage on the included wall wart. I don't have the measurements  handy, but they were disturbingly high for the application. So, I went to my local electronics parts store and bought a nice (over-overkill) 100VA, 28v transformer, a 7824 regulator, 4,700uF 50v and 470uF 100v caps and assembled a dead-quiet 24VDC power supply for the NAD PP2. While at it, I upgraded the power connector to a 2 pin screw-lock type, and replaced the plebeian NE5532 IC op-amp with a Burson SV6 Classic discrete op-amp. The results were quite pleasing to the ears, with the faster slew rate Burson and oodles of clean power at its disposal. 
 

So, yes - a wall wart can be a limiting factor, depending on the application, and the quality (or lack thereof) of the wall wart output.