Chorus Member Joined: 6/9/18
I should start by noting that I have very slightly below average hearing (nothing that requires medical attention, assistance devices, or anywhere near that level).
I have seen several shows, on tour and in NYC, that made me want to reach for the volume switch the entire show. I've wondered before if it had to do with the venue, the particular show, or both. Other times, the volume is perfect, so I don't think the answer is "I'm hard of hearing."
I've had this problem with various pit makeups (band vs. orchestra), music styles (rock vs. pop vs. full orchestral stuff). 
Am I the only one that's felt this way? The shows that have been the worst with this for me are Wicked and Dear Evan Hansen.
Broadway Legend Joined: 5/18/03
You are asking a simple question that has a complicated answer.
I will try to mention the various considerations, but a deep dive is a subject for a full book.
First of all, you are looking at sound regulations of the venue. Some venues have a maximum sound level that you must abide by, so that blocks you in on the high volume end. The flip side is that the quietest your show can be is determined by the ambient noise in the room - the sounds of the HVAC, the white noise of machinery, etc has to be covered by the sound (sometimes shows even turn off a/c during quiet moments).
Those things set the dynamic range of your show.
From there it is a matter of style, taste, and desired effect. Modern audiences are used to blasting headphones and TVs and going to loud concerts and movies, so they expect the sound to come TO them, rather than being active listeners, so there is a tendency for shows to lean 'loud', while some directors and designs actively try to push back against that by keeping the show quieter intentionally.
Of course, ALL of that then has the wrench of a live audience thrown in. Attendance of a specific performance makes the sound vary quite a bit. When an audience is more full, their bodies soak up some of the sound where as an empty audience can make a show seem louder because the sound has more hard surfaces to bounce off of.
The sound engineer controls the sound you hear. He is hired to travel with a show so the sound is modulated at each venue to be showcased in the specifications created by the show’s creators. If it’s too low or too loud, blame the creators of the show. That is what they require to represent their show.
Nevin Steinberg, sound designer of HAMILTON at the mixing board that the show’s sound engineer uses: 
I'm curious on the locations of your seats at Dear Evan Hansen and Wicked. Seat location may be a factor as well.
Stand-by Joined: 5/9/19
I will say when I saw Lightning Thief in “previews” the volume was incredibly loud. I wasn’t really very close to a speaker but there was a part where someone screams and it was ear bleeding. When I saw Head over Heels I got rush. Front row. I was literally RIGHT in front of a speaker. It was fine. I was concerned but it wasn’t bad at all which totally surprised me.
Broadway Legend Joined: 12/7/18
When I saw Wicked. I was in the very rear orchestra and I felt I was missing a lot of the action. That seems to be one of the larger theaters on Broadway but the Music Box isn't as large and I've never had sounds issues there.
Broadway Legend Joined: 5/15/03
I've had similar problems and had my hearing tested as a result. My hearing is remarkably good for a man my age. It's the sound systems that were at fault.
Stand-by Joined: 5/9/19
RWPrincess said: "When I saw Wicked. I was in the very rear orchestra and I felt I was missing a lot of the action. That seems to be one of the larger theaters on Broadway but the Music Box isn't as large and I've never had sounds issues there."
It is the biggest. Not trying to come off rude, just informing you.
Broadway Legend Joined: 8/15/15
I find Jagged Little Pill loud no matter where you sit. In the front row your feet vibrate from how loud You Oughta Know gets.
Broadway Star Joined: 11/10/14
I often have sound issues in BWAY theaters- and even in movies. My haring is also good. A lot has to do with the ability of actors to properly enunciate and talk slowly enough to be heard, Oftentimes, actors are simply not aware, it seems to me, how they are projecting, or how muffled they sound when they talk under their breath or talk extremely fast. I therefore, always get tickets in the second or third row of the orchestra- but this does not always insure a great audio. Many actors seem simply unaware of the issues of proper articulation.
You make a good point. I've watched Lehman Trilogy a few times (London's National Theatre, Park ave armory, and Nederlander) and I've sat from extreme side, 3rd to last row of mezzanine, and 2nd row center orch.... and never had any sound issues because all 3 actors enunciated and projected their voice very well throughout the play.
Chorus Member Joined: 6/9/18
mailhandler777 said: "I find Jagged Little Pill loud no matter where you sit. In the front row your feet vibrate from how loud You Oughta Know gets. "
yeah that’s one show I definitely had no volume issues with lol 
Chorus Member Joined: 6/9/18
Wick3 said: "I'm curious on the locations of your seats at Dear Evan Hansen and Wicked. Seat location may be a factor as well."
I’ve seen DEH twice, both on the tour, and I sat very close too the stage both times (need to see those Evan tears up close and personal).
Wicked I’ve seen several times, but the two most recent were front row (tour) and middle of orchestra right (Gershwin). Both times I thought it was quiet.
Swing Joined: 6/6/22
I recently saw Aint too Proud to Beg in Chicago at the Cadillac Palace theater .
I also saw it at the Imperial Theater on Broadway pre-COVID.
The difference in the sound quality was striking.
Broadway Legend Joined: 5/15/03
I finally caught up with WICKED in March and found the volume and singing were so loud that I was in actual pain. I nevet want to hear "Defying Gravity" again because it caused so much physical pain.
Because of constant and sometimes debilitating tinnitus, I wear high-fidelity concert earplugs to every musical I attend. It doesn't really muffle the sound, but, rather, lowers the volume and makes it less piercing and strident, and well as takes the sting out of loud audience applause and screaming. 
As a side note, I had no problem with the sound from second row orchestra center at  A Strange Loop, and I have no doubt that the plugs helped in that regard. These are the ones I own:
https://www.earpeace.com/
 
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