The supply and demand for those coveted Dead tickets

A fan at the Grateful Dead concert in Santa Clara, Calif.
Adam Jeffery | CNBC
A fan at the Grateful Dead concert in Santa Clara, Calif.

The "core four" of the Grateful Dead reunited over the weekend in Santa Clara, California, for the first two of five shows, part of their "Fare Thee Well: Celebrating 50 Years of the Grateful Dead" concerts. Originally though it was only supposed to be three shows, July 3, 4 and 5 in Chicago, but demand for tickets was so strong that promoters, along with the band, decided to add an additional set of "warmup" shows.

Billed as the band's "last shows ever," demand for tickets skyrocketed after the first public sale for the Chicago shows in February, when tickets sold out in minutes. That angered many fans when secondary sellers listed tickets for thousands of dollars above the initial face value of the tickets.

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On the official website for the "Fare Thee Well" shows, the band posted an open letter to its fans addressing the high prices and the additional shows. writing in part: "We have tried to do the right thing wherever we could for the Chicago shows by honoring the roots of where we came from, while dealing with the realities of the current times. But that's hardly comforting when you're (expletive) out of luck for tickets and your only option is inflated prices on secondary ticketing websites. That would piss us off too."

Outside the Grateful Dead concert in Santa Clara, California
Adam Jeffery | CNBC
Outside the Grateful Dead concert in Santa Clara, California

The result of the additional shows did in fact drive down prices. According to TiqIQ—a resale market ticket aggregate—the average price for a three-day pass to the Chicago shows is running just under $1,200. It may seem like a big chunk of change, but that price is a 68 percent decrease from the average back in February when tickets first went on sale.

The most coveted ticket of the five-show run is Sunday July 5—the final night the band will take the stage. Even that single-night ticket however has seen a dramatic decrease on the secondary market. The average ticket is just under $610 for Sunday—down 55 percent from Feb. 28, according to TiqIQ.

Read MoreGrateful Dead to put final five concerts on pay-per-view

Waiting to buy your ticket in hopes of the price dropping even more? Well, Chris Matcovich, vice president of data and communications at TiqIQ, said prices are still heading lower—just not as dramatically. "The prices, after dropping pretty steadily over the past two months for Chicago, have been trending down but very, very slightly over the past week or so," he told CNBC.

Just looking to get in the door? According to StubHub.Com you can, and it may not break the bank entirely. The average get-in price (meaning a ticket inside even if it is the worst seat in the house) for July 3 is $190, July 4 is $206 and for that final night July 5 is about $212.