It looks to be a good system. Ive always wanted to try an old sony es headunit. You should be fine even with 7 v because i would be you would probalby never be at the full 7v. If it is a problem then you should just be able to turn down the gains on the eq. Just because it can do 7v doesnt mean that it always will. Even crankup up with most real word music it will still probably not hit 7v. I have an 8v eclipse with an arc amp only rated for 2v and I have no problems. There are enough places to turn down the signal to accomidate just about anything.