Upgrade Tube Integrated or Buy Separate Pre-amp?

The Jolida amps are a nice simple design that are easily upgraded. Yes some swapping of parts will bring this amp to a new level. They are much better as an amp only removing the volume control and adding a active preamp.

Some may argue that modding doesn't improve the amps but it does. The coupling caps are cheap 10 cent Chinese CBB caps. Some decent coupling caps would be a good place to start.

If the modification results in the amp being a keeper for you, Detredwings' advice might be spot on. I know people who have been very happy with Jolida mods. If however, you're seeking advice regarding the next step on the path to audio rapture, a modification is not advisable. It is very unlikely that you will see a reasonable return on your investment when you try to sell. Frankly, I don't understand the preamp into the Jolida rationale so I won't go there. More and more high end manufactures are building quality integrateds. If you're squeezing dollars, I would stay that course for the time being.

As Phaelon said if your paying to have the mods done think it through. You will loose money if you want to upgrade. I got a 502 for a steal and did the work myself.

I know the preamp didn't make much sense to me at the beginning either. It would seem that your just adding something to the signal path. The Jolida is basically a amp with a volume pot. But after reading about it in some forum's I tried it. An it made everything better. Sound stage wider and deeper, extension on both ends. Even my wife who loves music but thinks I'm a little nutty with this hobby sat and listened. Her first words were wow that sounds amazing. Doesn't sound like the same amp.

I'm not one to put things into the signal path. On the contrary. In fact I took out balance and selector controls. You can try it by putting your volume to about the 12:00 position an plug in the preamp. Not as nice as the volume control removed but it will give you a good idea.