So, the questions are.....
How far are you from the other people and dogs when they start their aggressive behavior?
Which one starts it, of your two dogs?
What is your reaction from the get go?
Relaxed until you see someone else?
A bit worried
Tense
How do you correct them??
Yes they are feeding of each others energy...but this is very much correctable behavior. I just need more information.

Obviously, you are the trigger. That is not being critical. You definately are not trying to cause the situation. But, it also could be the way you walk the dogs leashed together.

What mazer says is true. More information needs presented.

Try this. Have your husband take the dogs just like you do and see if the same results happen.

If so, the method may be causing the bad behavior. Maybe the way they are leashed together.

Try separate leashes.

Do you let the dogs precede you? Do they pull at the leash(es)? In iother words, do you control the action or do the dogs walk you?

Try different things to try to isolate the trigger. Might be a protective trigger because of a rivalry when leashed together.

I think you may have something about rivalry. The Boston, Ziggy, is the instigator. He is the dominant dog in the house, since he was here first. The Doxie, Wally, was turned in to a kill shelter because"we have too many dogs". When I first got Ziggy at 6 months old, the rescue lady brought him to the house and said she had never heard him bark. A for instance is..we meet the same dog every day almost on our walk..neighbors who live down the street. Their dog is a black mutt, also a rescue, and my dogs go insane with the barking when they see him. I used to walk them with two leashes and got the coupler a few months ago. The barking was the same both ways. I hate to say it but the dachshund leads the way. He's a man on a mission and trots out beautifully taking Ziggy along with him. We walk very fast and I know they should be beside me, but I like them out front so I can see them and they don't trip me. I've tried several reactions..one I talk in a higher happy voice when we see a dog or a jogger, that didn't work. Mostly I pull them close to me and say quiet when they start. A friend said I should take treats along and give them when we see someone. Today on the walk, Wally ran over wiggling and licking when three joggers stopped to pet him. If Ziggy would have been there, he would have started the barking frenzy. We passed two cocker spaniels in their yard who barked at Wally, and he kept on walking, never even looked. If someone comes to the house, and pets Wally, Ziggy gets jealous and noses in but is never aggressive with Wally. They play fight gently biting each other. They both are terrific well behaved dogs at all other times. I realize the problem is more than likely their owner. Thanks for your replies. What should be a fun time sometimes isn't and I dread seeing another person or dog approaching us.

That dread actually increases the onset of an incident. The dogs feel your emotion, which provides fuel for their reactions.

Walking is a pack function. In the wild, dogs have a definate order of movement which follows the pecking order. The leader is always in front.

For a dog that is not the leader to be out front is confusing. Confusion leads to inappropriate behavior.

Sounds like individual leashes and a bit of training to walk along side you should fix the problem. Actually, what that is doing is making you the undisputed leader during the walk. That actually lets the dogs be much more content.

It sounds to me as if the Boston is protecting the Doxie. What is the result if you walk the Boston and hubby walks the Doxie? It sounds as if separate leashes will solve the problem.