When you say bad technique, do you mean just slow and slightly sloppy or bad to the point where it's inhibiting you from getting much better?

What bass do you use specifically? I know, you might be thinking why I'm asking that, but I tend to find certain bass guitars, can mask errors in your playing more (usually cheaper, and/or vintage designs), while the more modern design basses have a flatter fretboard, meaning a lower action and thus somewhat less stressful for the left hand.

As for 30 minutes per night, it simply wont be enough. I don't mean that in any offensive way, but if you really want to make some progress aim for at least 1 hour per night, and if your aiming to be a virtuoso, 2 hours absolute minimum a day, but upwards of 3 hours is really good.

The main reason why 30 mins simply won't be enough, you really should be spending the first 10 mins at the very minimum to warm up, but 20 minutes is probably a better minimum. If your currently not spending at least 10minutes to warm up, doing metronome exercises preferably, don't be surprised one day you may end up getting a crippling injury, as not warming up enough puts massive stress on the hands.

Before I get off track there, the problem with the 30 min practice, is that by the time you are done warming up, you only have 10-15 minutes to do anything else, be it learning a song, learning how to apply theory etc.

Best to find some time in your day for at least 1 hour, and spend the first 15 to 20 minutes warming up, doing progressively more difficult technical exercises, so at least you have 40 minutes left to really get into something, but as I would really suggest, aim for 90+ minutes if you really can.

 

 

Well that's a big part of the problem, not having a set routine. I tend to only have my first 20 minutes as a set routine, consisting of scales and modes being run all over the neck at various paces to warm up, as well as arpeggios. You wouldn't really need a book of exercises, I have made up of mine up, which goes some way to helping you shape your own individual sound. Things like chromatics,  major scales and modes to a metronome are perfect ways to warm up and to have as a routine.

As for the bass, I've never been a fan of the more vintage style instruments purely for that reason they aren't that easy on the fretting hand. A friend of mine has an Ibanez BTB405, which comes with active electronics (but the pickups are still passive I think), and can produce any tone from a rumbling low end, to a biting slap tone via the variable mid range active EQ. Also of note, is that it was way easier to play than any Fender/Fender style bass i've ever played. Other brands that have great playability are ESP and Spector basses, but really, it's up to you if your willing to sell your Fender, save up a little more and invest in something more versatile and comfortable.

 

Well the Chinese made range of Spectors are very very good value for money. The cheapest Spector basses are about the same price as a Fender Precision MIM (made in Mexico), so based on that, selling a Fender Jazz V Bass would easily have you enough money to get a Spector.

Did you get around to making a practice regime yet?

 

My daughter reached your level 18 months ago. Her bass teacher (Edwin Starr's UK tour bassist) , and after 5 or 6 more advanced lessons said there was little more he could do, but strongly recommended that she joined a band and got the discipline of playing with others. It took a bit of time to find a band,  with important school examinations intervening, but currently she plays and getting small gigswith a post punk band The Flaming Icecube.  Although the music is not her favourite sort, she tells me the practice and working with others makes it worthwhile.

 

Although it's not the case for everyone, but I've found it tends to be a lot better to actually consciously focus on what you're doing, rather than merely watching TV and playing. While I confess to have personally played in an 'unconscious' manner myself sometimes, I've found once you really train yourself to consciously focus on what you're doing, being able to get up and jam with other people and not having to always consciously think about what notes you hit, how you add nuances to them etc becomes more natural and controlled.

 

While it's still very important to do technical excercises to keep your musical muscles well toned (sic), there are few forms of music that improvised bass can't improve over memorised parts - and the best way to improvise is with other musicians, rather than recordings (unless those recordings are specially made ones with no bass line).