Ah, I just thought it was part of you PBJ arsenal!
My two bits on the D4 is that it is a very light and portable amp, that sounds absolutely amazing and punches far beyond it's weight. I'm guessing your BA108v2+ can get louder, but the D4 can keep up with an acoustic guitar played enthusiastically. At that size and weight, you could almost just carry it with you when you go continent-hopping. Bring a battery, and you won't even need to worry about plugging it in.
Very probably a BA108v2 can hold its own in an acoustic match (no banjos!). But at ~30 pounds, why take it when there's a PJB BG400 combo at 40 pounds? And equally reasonable to question why not practice with the BG400? My answer is, because the little 'Peg sounds smooth to my ears. Not better, not worse, different. More than once I've considered an Ampeg BA112v2 just for the tone and a "go to" for low volume "that tone".
"That tone" to me right now are Dunlop flats on my Chowny CHB-1, and it's been a difficult decision
and I'm staying with it. TL;DR warning beep beep beep
What I had in mind with the semi-hollowbody bass is that The Animals vibe. The Filter'Trons, the thud, the whole thing. Eventually settled on La Bella Low Tension Flats and stayed with them throughout the 40 weeks' music theory course. And as a result of that course material, found myself practicing above (and sometimes well-above) the 12th fret
and yes I know all the money is below the fifth fret and who said there's money in this right now?
:: looks around ::
What I find I need beyond the Rubicon is more articulation and less thud for what I'm doing, and in all this foolishness
install Dunlop flatwounds three months ago to hold that space between :: whatever weird criteria is in place for vintage and modern :: And you know what? The Dunlops are super nice. They keep their tune for days, literally. Maybe a couple cents, but I could really pick it up and not tune (bad, bad, bad) and be very close to spot on.
What I did not account for is the incoming Nordstrand Acinonyx. It'll be "my bass" for the new start of the
Music Theory for the Bass Player cohort that begins on Friday. (It'll arrive when it arrives, February-ish by the blessings of the FSM.) I'll be playing it with either the stock DaD nickel rounds, or GHS Balanced Nickels, (or maybe Pressurewounds) which means
the Low Tension Flats might go back on the Chowny for maximal thud. Or keep the Dunlops that are very barely broken in. What I can report is the Chowny puts out some serious thud in both cases
.... ain't a lot of bum-thumping thud in the BA108v2+ but that's not what it's for. And I really like it for what it's for.