At a Chip Kelly training camp, an automated voice periodically thunders over the loudspeakers. The voice signals that it’s time for a new drill, and players respond by moving briskly to the next station.

But every few sessions, the voice says one word to bring everything to a standstill: “Teach.” Players gather ’round their position coaches for a lesson on how things are going to work in the Chip Kelly Era.

“We believe the game of football has two speeds. There’s game-speed and then there’s teach-speed,” Kelly said early in training camp. “So, there’s no reason to do something three-quarter speed because you’re never going to play that way.”

There is much to learn for an offense that will play at a breakneck tempo with schemes that will look dramatically different. The Philadelphia Eagles used three or more wide receivers 70 percent of the time last year, according to Pro Football Focus.

The 49ers used three or more wide receivers just 41 percent of the time.

Class is also in session for a 49ers defense that needs to start training for its upcoming marathon. The Eagles defense was on the field for an NFL-high 1,148 plays last year — that’s about 72 per game.

As he prepares for his first season in San Francisco, however, the questions surrounding Chip Kelly go far beyond how well he can teach.

There’s also the matter of how much he’s learned.

“I’m sure Chip’s heard the rumors,” 49ers linebacker NaVorro Bowman said, “and I’m sure he’s made a few changes so he doesn’t have the same comments at the end of this year.”

The comments would be hard to ignore. Kelly was chased out of Philadelphia amid verbal torches and pitchforks. He was “released” from his contract with a game still on the schedule.

Even this summer, Brian Mitchell, a former Philadelphia return man turned Comcast SportsNet broadcaster, remains baffled by Kelly’s trail of alienation.

“I don’t understand how you get in a league like this and you basically don’t communicate with players, you don’t make them feel comfortable,” Mitchell said.

“(But) things I’ve heard from different players is that he was kind of standoffish. That may work in college, because in college, the coach is the guy. In the NFL, if you don’t do well, they won’t get rid of all the players: They’ll get rid of you.”

Kelly, 52, did well — and the Eagles got rid of him anyway. He went 26-21 over his three seasons in Philadelphia and led the team to the NFC East title in 2013. But along the way, he irritated people about as quickly as the Eagles scored points — the hurry-up offender.

This wasn’t off-the-record, according-to-sources stuff, either, but rather repeated haymakers from players (or, more often, ex-players) willing to put their name on it.

Offensive tackle Lane Johnson, who was Kelly’s first draft pick, said the coach was undone by “not being human about things. Not working together, with the team, instead of being a dictator.”

Evan Mathis, fresh off a Super Bowl victory: “The Broncos team I was on would have eaten Chip alive. I don’t think he could have handled the plethora of large personalities.”

Cornerback Brandon Boykin: “He can’t relate and that makes him uncomfortable.”

Running back LeSean McCoy: “You see how fast he got rid of all the good players. Especially all the good black players. He got rid of them the fastest.”

Things got so grisly by the end of his tenure in Philadelphia that it was almost easy to forget that he won 10 games in each of his first two seasons. He also kept the offense mostly humming: the Eagles ranked third in the NFL in both points per game (26.9) and total offense (392.8) over his three-year tenure.

By the time the 49ers hired him, on Jan. 14, his reputation was so in tatters that Kelly joked that he had to go beyond “self-scouting.”

“I looked at it as more of an autopsy,” he cracked. “So I sent some toxicology reports out and we’re going to see when they come back. I’ll give you a full answer in terms of what went on.”

Kelly never did announce the results of those lab tests, but it was clear by early training camp that he’d ruled his death in Philadelphia as “accidental.”

Far from chastened, the coach said that for every player who criticized his methods, there were plenty of others in his corner. Kelly also noted that during his brief period of unemployment, he got calls of support from some of the most respected minds in the game: Bill Belichick, Jon Gruden, Bill Polian, Tony Dungy and Nick Saban.

“It made me feel good that there are people in this game that truly care about where the game is going and what this league is all about and what direction it’s heading in,” Kelly said. “(They’re) telling me, ‘I hope you stay in the National Football League.'”

There have been no signs of surrender in Kelly’s approach, no revisions to his methods, no changes to his temperament.

A reporter asked Kelly this spring how he’s different now that he’s about to take over the 49ers.

“The ocean is on the other side,” Kelly quipped. “If I was facing north in Philly, the ocean is on the right. Now the ocean is on the left.”

So, no, there is no such thing as Kelly 2.0. The 49ers are getting the classic model.

“I’m not governed by the fear of what other people say,” he said. “I have conviction in terms of how things are supposed to be done, the collaboration that has to go on within the organization for you to be successful.

“And if there’s going to be a critic of that because they don’t agree with it or they don’t understand it, then I can’t change. I can’t take a pulse of what everybody feels like and say, ‘Hey, let’s do it this way because the public perception is it should go that way.'”

Public perception has never been on Kelly’s radar, not even in the best of times. When he was promoted from offensive coordinator to head coach at Oregon, he asked Mike Bellotti, who became the school’s athletic director, to continue making public appearances and meeting with boosters because Kelly couldn’t stand making small talk.

The Washington Post recounted that tale last summer in trying to find out more about Kelly beyond football. What they found is that Kelly’s family has been ordered to keep quiet in public about Kelly. Mike Zamarchi, the coach’s longtime buddy, told the paper that Kelly’s friends are “sworn to silence.”

For the 49ers, though, the introductions have been smooth. Veteran players, eager for a semblance of order after the Jim Tomsula era, embraced a head coach who arrived with a clear sense of purpose.

Bowman and safety Antoine Bethea, two of the 49ers’ most influential locker room leaders, repeatedly sang Kelly’s praises.

Kelly said he’s simply doing the same things but with a more receptive audience.

Take, for example, his approach to sports science. MMQB a few summers ago documented the gizmos that Kelly had the Eagles wear, having spotted linebacker Connor Barwin wearing “a GPS, magnetometer, accelerometer and gyroscope that had just recorded his every movement on the practice field.”

Kelly has not divulged the extent of his sports science approach with the 49ers, except to say that his methods no longer seem so unusual in the heart of Silicon Valley. He said he has the full cooperation of Jeff Ferguson (the team’s head trainer and vice president of football operations) and Mark Uyeyama (the team’s director of human performance).

“For some reason, no one heard of sports science until we got to Philadelphia. It was going on everywhere in the National Football League,” Kelly said. “And these guys (with the 49ers) have been on the cutting edge of that for a long time.”

His X’s and O’s, also the source of much scrutiny in Philly, appear as unchanged as his persona.

Kelly’s no-huddle offense first created a stir at Oregon, where his Ducks went 46-7 from 2009-12. His 2010 team averaged 47.0 points per game.

In the NFL, however, Kelly’s offensive approach has been a mixed bag. The prevailing criticism is that it asked too much of the defense, and stalled a bit last year when it appeared opponents had cracked the code.

Mathis, the Eagle-turned Bronco, once called it “a never-evolving, vanilla offense that forced our own defense to play higher than normal play counts.”

Mitchell, who now works as an analyst for Comcast SportsNet in Washington D.C., is also a skeptic.

“Most teams run 60-something plays a game. (Kelly) wants to run 90. What are you thinking on the other side of the football?” Mitchell said during a celebrity golf stop in Tahoe this summer. ‘These are professional athletes, not college teams you’re going to beat by 50.”

Mitchell doesn’t buy the argument that defensive players relish their chance to carry the load.

“Bull,” he said. “They want to make plays when they’re rested. … The guys in Philly talked about how tired they were. The whole team had problems with it. The offense wasn’t producing, they weren’t getting first downs.”

The Eagles finished 7-9 last season as Kelly’s weary defense finished 30th in yards allowed.

For the 49ers, however, almost any new offensive wrinkle will represent a giant leap forward. San Francisco scored 14.9 points per game last season — comfortably last in the NFL.

While the attention has been on what Kelly can do to revive the quarterbacks, the safer bet is what the coach can do for the running game.

Under Kelly, multitalented back McCoy amassed 1,607 rushing yards and 539 receiving yards in 2013. Pro Football Focus ventured that Hyde could have a similar breakout, arguing that the two backs are similar aside from one key difference: In his best season, McCoy’s elusive rating was 48.8. Last season Hyde’s elusive rating was 78.7, the second-best mark in the league.

“It’s going to be interesting, because (Kelly) really believes in the running game,” said Ron Rivera, the head coach of the Carolina Panthers. “And Carlos Hyde is a tremendous football player, that, when healthy, has shown his ability in this league. So he is most certainly a guy we have to watch.”

Kelly becomes the 49ers’ sixth head coach since 2003. The ones not named Jim Harbaugh are a combined 51-93 (.354).

The 49ers believe Kelly can get things back on the winning track — with or without new friends.

“I’m not in the conception business,” the coach said. “We’re just trying to play football.”