Roland RD-88 sound envelope adjustment ADSR

[bluesmuso]

I have recently bought the Roland Rd-88 which I am pretty happy with. I was going to go for the Kurzweil SP6 but the onboard speakers in the RD-88 won me over for practicality.

I cannot find a way of adjusting a sounds envelope (adsr)
I cannot find an envelope generator onboard at all. I simply want a sharp arco string sound but with a sawtooth wave rather than a dedicated string sample. I am wanting to play 'All my love' by Led Zeppelin so I need that arco string synth sound.
I can find the right sound on the RD-88 but not the right envelope settings and cannot adjust attack or release without the ADSR edit ability.

It's really frustrating that my old Korg X50 has the perfect sound but I cannot find or create it on the Rd-88 in spite of having 3000+ sounds WTF!!!
I had limited success playing around with velocity settings to get the staccato string sound but still no where near what I want!
My old Roland Juno DI had the same sound too, a sweet, sharp arco string sound!

any help would be appreciated thanks