A common thread between the three similar, treat but disparate sets from The Districts, Lady Lamb and Sun Club might have been intensity.

At a sold-out Sinclair on Tuesday night,The Districts made their return to the area, touring in support of A Flourish and a Spoil. The Philadelphia-based band is quite strong in a live setting. Rob Grote’s gravely voice evokes rockers of a bygone era.

The band’s willingness to let songs unspool themselves on the stage, with polished, extended jams, is a very welcome antidote to four-minute, radio-ready hits. “Young Blood” verges on nine minutes on the record, and it is a rollicking tune to close out a set.

Supporting The Districts on tour is Lady Lamb, a band tha recently headlined The Sinclair for the release After.

When I first saw Lady Lamb, songwriter Aly Spaltro performed solo at Afterhours, a Northeastern club/Starbucks, supporting The Antlers. Hearing “Bird Balloons,” the song I’m positive she opened with, was nothing short of incredible. The winding, nearly structure-less, tune alone was enough to make me a fan.

I wonder how many unassuming Districts fans had that experience on Tuesday night – I’m sure there were at least a few who did.

Touring as a three-piece band, Lady Lamb played songs from After and the debut, Ripely Pine. “Bird Balloons” had an unparalleled intensity to that night at Afterhours, with harmonies from bassist TJ Metcalfe.

It’s such a fortunate circumstance to get to see Lady Lamb perform in an intimate venue like the Sinclair, especially as support. The band is poised to headline bigger venues in the future, I would expect — and perhaps score slots at a certain area festival (please, please, please).

Baltimore’s Sun Club opened up the evening — well, a pair of scantily clad people emerged and danced without explanation. Then Sun Club emerged, and I have very little explanation for what I heard. The five-piece band is probably best described as psychedelic rock, with discordant vocals and fuzzy, reverb-soaked guitars.