Nope. First of all, there is no such thing as an 8ohm or 4 ohm speaker. What you have is a speaker with a nominal impedence of 4 or 8 ohms. The actual impedences varies considerably throughout its range. Some nominal 8ohm speakers have droops in the impedence curve to 2 ohms or less, usually in the bass, and rises to 16ohms or more in the mids/highs. Ditto speakers with a nominal rating of 4 ohms. Such speakers present major difficulities for many amps. Impedences droops require more power. An amp that doesn't double its available power to a 4ohm load will clip much earlier when called upon to support the droop in impedence than will an amp which doubles its power into 4 ohms. Hope this description makes sense to you.
4ohm, 8ohm speakers and output power
Assuming that two speakers both have the same sensitivity rating, but one having 4ohm and the other having 8ohm.
For example 88db/watt/meter.
Now usually and in most cases, a given amp can have its output power doubled when driving a 4ohm loud vs. an 8ohm load.
Does this mean that in theory, the 4ohm speaker can play louder than an 8ohm speaker given they use the same amp since the amp can deliver twice as much power to the 4ohm speaker? And since they have the same sensitivity, more power equals more louder.
For example 88db/watt/meter.
Now usually and in most cases, a given amp can have its output power doubled when driving a 4ohm loud vs. an 8ohm load.
Does this mean that in theory, the 4ohm speaker can play louder than an 8ohm speaker given they use the same amp since the amp can deliver twice as much power to the 4ohm speaker? And since they have the same sensitivity, more power equals more louder.