New Breaker Box-Should I upgrade?

I don't  think  a larger box would improve your existing lines you aren't  drawing  anywhere near 150 amps at any one time. If you have ideas of a future project that will require more lines all I can say is the price won't be cheaper in a few years to add a new box.

Your electrician is correct.

What in the world are you doing with "all my dedicated audio lines"? You should have one. ONE!

But hey, don't take my word for it. Who am I? How about Mikey then?
Skip to 15:50 for Fremer's advice on dedicated lines. https://ultimist.com/video/2018/07/21/michael-fremers-listening-room/

So absolutely do not bother. BUT if you are like a lot of guys and really, really, REALLY stubborn especially when it comes to learning, then you STILL do not need another breaker box. Because you can keep all your unnecessary lines and still add more simply by swapping a few existing breakers out for thin twins. These are what they sound like, breakers that take up half the space. Surprised your electrician didn't tell you this.

Well no not really. After 30 years I am no longer surprised to find I know more than the electricians.

2. Would a larger capacity box provide me with a better supply of current that would, in turn, improve my dedicated audio lines?

No. Not even. A larger box is a larger box. It will have a bigger main breaker, yes. But you really should step away from the keyboard and go have a look inside there. It won't kill you to look. Honest.

Does it look like the panel is going to have a bigger wire coming into it? Or are you going to have them change the cable from the pole to the meter to the panel? While you're at it, about that meter...

Reality check. Hope its been useful.

1. Should I bother, when everything still works?

No.

2. Would a larger capacity box provide me with a better supply of current that would, in turn, improve my dedicated audio lines?

Nope.  What you could do however is move your audio lines to a separate sub-panel, and put a filter on that!

The electrician discouraging it is your answer. Good tradesmen do not like doing unnecessary work.

If your main circuit breaker has not tripped then there is no reason to upgrade. It all depends on what else the house has. I have central air, hot tub, electric stove , well pump, etc. So I need 200 amp service. If I did not have 200 amp service the main breaker would trip!

The standard for household power used to be 60 amps. But modern homes may need as many as 200 amps to run air conditioners, computer equipment, high-definition televisions, and high-tech home automation devices.

I agree with the above answers of no need to add a 200 amp box. To that I would add that should you find a need to add additional circuits go this route: https://www.acehardware.com/brands/square-d/34028?x429=true&msclkid=3dcfdc4d5f2710318d198273f884...

@yogiboy HD TV uses less power than old CRTs! LED lighting a lot less than incandescents. 

Agree with comment to replace many lines with one big one. I know because I found out the hard way that one big 8 gauge pipe sounded better than 3 x 14 or 2 x 12 gauge runs.

To all.
I have a two separate stereo systems. As well as, separate lines for computers/network/washing machine and dryer, etc.
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@erik_squires

move your audio lines to a separate sub-panel, and put a filter on that!

Good advice. I did that in a former house (except no filter) and it worked great. Currently running three 20A lines a short distance from the main (200A) panel, which is plenty for my one main system.

Seriously??! Add a panel??!   Add a freaking panel?!!?!

Keep all the unnecessary lines, even after Michael Fremer explained precisely why that is a bad idea, and then add to that even more unnecessary connections. Add a whole new panel for which there is no need whatsoever. That is like the worst suggestion ever. And you think it is good advice.  

Okay. I am outta here!

Don't let the door hit you on the way out.
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Fremer was using the $18,000  AC Nexus Advanced Power Distribution & Ground Enhancement System by SMc Audio, and for an additional $8K they will throw in a four-foot EnKlein David power cord.

The SMc Power Distribution device uses a 15A input.  My Isoclean 60A3 is in the same boat as there are indeed three 20A outlets on the device but it only accepts a 15A style power cord.  I use it to power everything except my monoblocks.  I doubt a single 15A or 20A line would be enough for my whole system when SMc Audio themselves suggested providing big power to my new SMc monoblocks, each of which have a 10A fuse. 

All of this is moot if @gdnrbob is happy with his current power situation.  However, if not, depending on the makeup and location of his system(s) running a single big line (50-60A?) to a sub-panel located near the system may be a better solution than running multiple lines from the main panel to the room, especially if the room is a long distance from the main panel.  Power lines from the panel will all be grounded the same and can then be used solely for the audio system(s).   

Fremer can do what he wants.  I have never had a problem using a lot of clean power grounded from the same side of the panel, front-end stuff through a filter and amps from the wall. YMMV

Just for info twin breakers are not allowed in all panel boxes. I would assume your electrician knows this, there is usually a diagram on the box showing how many and where in the box they can be used. 

I looked into that as well, was told I would have to change out the lines in the house to accommodate the higher voltage......was to expensive.  just going to get a new more updated, bigger box...150 is enough I find.

@kennesawjet ,
Yes, I was hoping to do the same, but the electrician said a larger box only came with a higher amp capacity.
I'll be leaving things alone for the time being.
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