How do Pentecostals or other Charismatics respond to criticisms about 'speaking in tongues' by multiple people at once and without interpretation?

I found a thread on Christian Forums titled "Speaking in Tongues Corporately Without Interpretation" which has some interesting posts addressing exactly the question you ask.

In short, Pentecostals seem to distinguish between at least two different functions of the gift of tongues:

1. Tongues for self-edification in the form of prayer or worship to God (see 1 Cor 14:13-15 about praying and singing in a tongue).
2. Tongues that require interpretation for the edification of the church, making them equivalent to a prophecy (see 1 Cor 14:5).

Pentecostals would concede the criticism in those cases where people start speaking in tongues for self-edification (function 1) in a chaotic manner, becoming a source of distraction for others and disrupting the normal flow of the service. If you are going to attract the attention of others to yourself, you should only do so in an orderly manner and provided that someone interprets, so that everyone is edified (function 2).

However, Pentecostals would not concede the criticism in the special case of corporate worship and prayer. These would be special moments during a service in which everyone agrees to pray and worship God out loud, either in a tongue or in their everyday language. No one is in the spotlight, no one is disrupting the service, because everyone is on the same page. And, therefore, there is no need for interpretation. You can think of it as a corporate self-edification: each one is edifying themselves simultaneously.

Below a few quotes from the thread (emphasis mine):

I tihnk often people have the misconception that a tongue always has to have interpretation to be valid and biblical. Not at all. Paul himself said that the person is edified when they speak in a tongue; nowhere does he prohibit tongues though. In 1 Cor.14 he says that if there is no interpretation a person is to sit down and speak (natural reading: in tongues) to themeselves. Nowhere does he say he was wrong to speak and not have an interpretation (how could he know) and in saying he could speak to himself, Paul implies that a tongue can be used biblically without interpretation.

Remember the context of 1 Corinthians - "in the church" as Paul says several times in ch.12-14. He is speaking of a specific setting where tongues are used for the edificatoin of the church. Now when a tongue is intended for the church, it should be interpreted. In it is for the church and no-one understands it is unloving and confusing and separates the church into the tongues-speakers and non-speakers. But not all tongues are for the church. Paul used them all the time, and he never rebuked the fact that tongues-speakers would edify themselves when speaking in tongues, even though they do not understand what they are saying. That means whenever you use tongues in a way that is not intended for the church's edification, you can use it, e.g. praying in tongues during individual worship, singing in tongues during corporate worship (it's directed to God, not to others), praying corporately in tongues (each person is praying between them and God, not to each other).

I think that if you are praying in tongues in a group that is fine...if you are speaking in tongues as a form of prophecy then it needs to be interpreted.

2 completely different circumstances...

Most prayer is done singularly, while everyone else either listens or trys to pray along with the person praying.

Corporate prayer where everyone prays and intercedes together to God can be and in fact is very powerful prayer, and should not be discarded as confusion.

Many times during my quarter century as a charismatic, have I been in a local service where during praise and worship, innumerable tongue speakers went off into a praise--usually monotone of sorts--corporately in tongues, and it was as if we were all transported to Heaven for a moment and were listening to the Heavenly angels worshipping before the throne. In fact, on some charismatic praise and worship cd's, it is not uncommon for such a thing to happen at the tail end of a song or during an instrumental part. Glory!

Let us not put God in a box, especially when we make His written Holy Word to have a broader--or narrower--application than what was intended.