I got an old silver fin Peavey Microbass amp, from the mid to late 80's in a sweet package deal. It sounds alright, but am curious what I could get out of it with a small speaker modernization. I was directed to winisd but it looked confusing to my simple mind. I am looking at an MCM mid range driver that is very affordable (sub $20). specs...an online calculator I found said this would work in a sealed or ported enclosure. Nominal Diameter:8 inch. Rated Lmpedance:4Ohm. Operating Bandwidth:60 ~ 6KHz (-3dB). Power Handling Capacity:70W RMS. Sensitivity (1W/M):89dB (Â±3dB). Voice Coil Diameter:1 inch. Thiele-Small Parameters: Resonance FrequencyFs:28.8Hz. DC ResistanceRe:3.4Ohm. Mechanical Q FactorQms:3.4. Electrical Q FactorQes:0.5226. Total Q FactorQts:0.4529. Equivalent Cas air loadVas:98.26 L. Surface Area of ConeSd:0.0216 m2. Efficiency Bandwidth ProductEBP55.1. Voice Coil Over HangX-max3.5 mm. And also at a slightly more expensive Faital driver, the 8FE200. specs are easy to find. Online calculator said this driver would work best in a ported cab. I feel I may be starting a fire storm. I know that speakers and cabs are matched, but have read of good results with putting quality modern drivers in these little combos. I'm not looking to shake the world, just sweeten up the tone and low end a bit. And if the speaker gets over $50, I would rather just buy a new combo. please keep that in mind. any and all direction is appreciated. even if that is rightly telling me the idea is stupid.