hey everyone, new to thread but have been silently following along and inching my way towards build 4 skrams for my system as well. the latest rabbit hole i've found myself stuck in is whether b&c 21sw152 in either 4ohm or 8ohm impedence would be best in my unique situation (power limitations). i was hoping all your fine folks could help me make a decision. much appreciated.
the near term plan is 4 skrams (2 amps on subs so one per channel) but that number will eventually grow to 6 skrams where i would likely run all 6 off the same 2 amps (2 in parallel on one channel and 1 single on the other channel). amp specs would be
A few questions i have hoping to get some clarity on:
i had initially set my eyes on 21sw152-4ohm. if i plan to set RMS limit to 50% of continuous power handling (1000w), it appears that its generally easier to find amps that better power match the 21sw152 4ohm rather than the 8ohm version (i am targeting 6 to 9dB headroom before clip). based on the above, it seems like there aren't many (affordable) amps that can properly power the 8ohm drivers. to achieve similar SPL between 4 or 8ohm during operation, would it simply come down to adjusting the amplifier's line sensitivity (higher for the 8ohm) to compensate for the higher load? ie: 63vrms into 4ohm vs 89vrms into 8ohm - both yielding 1000w). spec sheet's sensitivity between the two versions appears to indicate so.
conversely, although 8ohm offers higher damping factor, there is supposed to be another benefit of allowing a given amp to power more skrams down the road if the system grows (ie: hang more higher impedence drivers in parallel etc). HOWEVER, is this really the case:
1. if the amplifier of choice doesn't have enough power to properly drive anymore than 2 skrams per channel anyway. 2. if 99% of venues have limited ac power supply (120v 15a service only but with multiple independent receptacles).
i found some of the responses to Domme's question regarding the Eminence NSW operating at 6ohm driver quite helpful and somewhat relatable but am wondering if the recommendation changes given the power supply constraint? damping factor sounds like a serious consideration but given how difficult (read expensive) it is to power these 21sw152s at 8ohm, i suspect 4ohm may make more sense for my application?