It really depends on the driver. If the diver is incapable of producing 50hz without overexcursion, then it would be a waste. If the frequency response is declining rapidly and then there is a tiny shelf at 50 hz that is down 10dB from the peak around 100 or so, that would not be all that useful either. If you are using a sub that easily covers up to 100hz, it would not be particularly helpful to have the low mids tuned so low. Remember that you also often lose sensitivity in trying to get a lower tuning.
On the other hand, if you are going for something that might be able to do full range without a sub, I would aim for a design and driver combo that can do a useful 40hz.
I can't really give you a straight answer. It is down to what your driver can do, and what you want.
Many great song writers began by playing covers (learning other people songs) first. This taught them structure, timing and what chord progressions work.
Maybe look at some DIY designs and put their properties into a couple of different design programs, WinISD, Hornresp etc, then play around to see how changes effect the performance. Your learn a lot from this if you are new at it.
agreed with roger hear, your looking to put a round peg in a square hole..... Pointless trying to phase bung a square / rectangle throat....
Ive been playing with phase bung design for close to 4 years, there is no quick way to do it, and to get it right means a lot of prototypes and a healthy chunk of money....
Right, but I don't understand why people on here can't just help, instead of telling me I'm wasting my time or 'I'm running before I can walk' I'm simply asking for help because I don't know these things. Again. I want to put a phase plug in this design, preferably the rcf 10 plug, so if I have to I'll make the horn round. I know it will take a while but it will take fucking for ever if people just tell me It's hard