Sorry if this has already been answered in the various speaker-replacement threads I've been going through, but I still feel a bit lost after reading many of them. I just bought a Sunn SB160 combo amp for $100 to replace my previous practice amp which wasn't making it through the mix. All I was looking for was something very cheap and very loud. It's in poor shape, but meets these criteria and then some. At only 60 watts this thing gets more volume than some 200 watt amps I've heard. However, the speaker ring is gone, the cone is pretty beat up, and the dome is quite banged up as well. So though I'm getting great volume, what I'm missing is anything close to resembling a good sound, and the speaker is going to have to be replaced. The original speaker is 15", 8 ohms, 80 watts RMS and 160 watt program. I've done a fair amount of research on my own for a replacement, and I'm looking for something quite cheap, so I've come to the conclusion that the Eminence Beta 15A is what I'm looking for. I'm looking for outside opinion as to whether or not this is a good choice for two main reasons. First, I'm told time and time again that there is no such thing as underpowering a speaker, but since this thing is somehow able to get so goshdang loud with only 60 watts of output from the amp, my concern is that the rating on the original speaker is optimal for this setup, and that when switching to a higher rated speaker I might lose much of this massive capacity for volume. Is that something that makes any sense at all? Second, I've read that the Beta is particularly bassy. Considering this old Sunn consists mainly of a poorly constructed fiberboard box, undoubtedly designed with little concern for how it's dimensions or interior surface will affect the sound, would this speaker be a poor choice? Not that producing amazing tone is a concern of mine, but I wouldn't want to be left with all boom and no definition. As far as improving the sound of the cabinet itself, I know placing foam inside is often recommended. Is there any specific method to this? Should some surfaces be lined and not others? I'm not looking to put more than another $100 into this, and I'm not expecting any miracle improvements here. I'm well aware that only so much can be done. Just want a more useable practice amp and a little project to occupy my time. Thanks!