Nico Rosberg revealed running the 'megaphone' exhaust tailpipe during testing "didn't change anything" with regards to the sound of his W05.
On Wednesday, the second day of testing at the Barcelona circuit, Rosberg put Mercedes' new innovative 'megaphone' exhaust through its paces.
It was hoped that the exhaust would amplify the sound, putting an end to complaints about the new quieter sound of Formula 1.
The exhaust, though, did nothing to improve the sound.
"Unfortunately it didn't change anything so we need to keep pushing," Rosberg told reporters at the track. "We want to, as a team, make things louder for the sport.
"We need to keep pushing and try some other solutions because this was not the right solution. It was the same - nothing."
The German, who ran the modified exhaust tailpipe for 13 laps, also confirmed that the device did not alter the performance of his Mercedes.
"There was nothing, it was all the same," he added.
Removing it after his initial run, Rosberg, who dropped to second in the Championship behind Lewis Hamilton in Spain on Sunday, focused on what he needs to improve in order to catch his team-mate.
Adding a further 89 laps to his tally, he completed the day second quickest, 0.934s behind Lotus driver Pastor Maldonado.
"Days like today are so valuable as you can't really test anything effectively during a race weekend," Rosberg explained.
"No one run is the same as another, whereas here you can keep certain variables stable and properly compare things back-to-back.
"One of the main things we looked at was braking. This is an area where I haven't felt 100% happy yet this year, so we're continuously assessing ways to improve on that.
"We also worked on starts as this has been a bit of a weakness for the team this season.
"It's not easy as it's such a sophisticated procedure and there are some highly complex parts involved like the clutch, for example. But we definitely learned some interesting things."
Looking ahead to the next race on the calendar, Rosberg says Mercedes are intent on staying ahead of their rivals while he's hoping to add a second Monaco GP win to his tally.
"Our aim is keep increasing any advantage we can find over our rivals and the team is doing a great job at that.
"Of course, Monaco is up next and that's a very different, special race. But our car is strong in all areas and I see no reason why we won't be just as competitive there."