Appeal organiser the Royal British Legion have turned to pop acts in recent years to raise the fund-raising profile.
The band were in Covent Garden, London, on Thursday with Dame Thora Hird to launch the appeal, which this year aims to raise £20m.
The group's Jon Lee said: It is very rare we get any silence - we are all very rowdy."
All seven members' grandfathers fought in the war and they said they are keen to boost interest in the appeal among the younger generation.
Tina said: "We are raising money for old war veterans - we have family who risked their lives for the country and we must remember them and hope to raise young people's support."
Dame Thora, 89, said: "Young and old can unite to support a unique institution which continues to offer unparalleled support to ex-servicemen, women and their families.
"I wouldn't be here if it wasn't for those war veterans."
Appeal organiser the Royal British Legion have turned to pop acts in recent years to raise the fund-raising profile.
Last year Irish heart-throbs Westlife launched the drive for funds and in 1997 the Spice Girls were involved.
Noel Rogers, chairman of fund-raising at the Royal British Legion, said: "Once again it is marvellous to see the Poppy Appeal supported by all generations highlighting the relevance of our annual campaign.
"The Poppy Appeal is the life-blood of the Legion's welfare programme.
"Wearing a poppy, the symbol of remembrance, is a small yet significant gesture when we remember the price of freedom."
The legion is calling on people to observe the two-minute silence on Armistice Day at 1100 on Saturday, 11 November.