Wharfedale Delta 218 with RCF Drivers

I have two Wharfedale Delta 218 dual 18" subs that i've used for quite a while and they're pretty good subs but instead of selling them for something more powerful I was thinking about taking out the drivers and putting in either RCF LF18G401 or L18P300 drivers. I'm leanign towards the G401 due to it having a bit higher xmax.

I've used WinISD to plot the probably frequency response (i'm not a pro at using it) and all looks ok to me. The subs both have two seperate chambers, one for each driver and the internal volume of each chamber is (as far as I can work out after measuring inside and calculating) about 143litres. The insides of each chamber measurements are :  depth : 560mm, width : 470mm, height : 500mm, the 4 port are triangular and the measurements of each port (each sub chamber has 4 ports) is 390mm long x 150mm wide x 80mm high. Inside each sub chamber 18mm thick bracing runs from top to bottom and is 100mm depth.

Do you guys think 143 litres for each chamber is about right and am I right in thinking the RCF LF18G401 or the RCF L18P300 drivers would be perfectly fine? I want to upgrade the drivers because I want better sound quality and higher output of bass, I play drum & bass, techno and oldskool hardcore rave which really punishes most subs when run full.


Edited by djteknovibe - 23 November 2016 at 8:34pm

I had a make a new account because I changed my email address and got locked out of my account and after trying about 15 times to get an email activation sent to my new email address nothing ever arrived.


Anyway, is there another driver for the Wharfedale subs enclosures that you can think of that might be better considering the internal dimensions and port size etc...? Or is the RCF L18P300 the best I could have in the sub enclosures? I've probably heard the P300 in subs at raves and in clubs but never knew it I should think.

Here are two frequency plots, the first is at 1 watt input and the second is at 1,000 watts input,  this is for one driver not two as the Wharfedale Delta 218 subs have seperate chambers one for each driver and in WinISD I plotted it for one single 18" sub chamber. So I guess peak spl i'd add 3db for a single dual 18" sub loaded with the LF18P300 drivers right?












Edited by DJ_Teknovibe - 24 November 2016 at 10:43am

The first graph shows that the vent mach is in the green so it's ok. I've remodelled the subs using 111 litres and the subs (each chamber) is -3db@46hz using the RCF LF18P300 drivers.  The WinISD program doesn't allow for triangular ports so I had to add the ports width and heigh together to simulate it as if each chamber had one square port.


Edited by DJ_Teknovibe - 27 November 2016 at 9:25pm

What a dickhead I am I miscalulated the port dimensions which was giving me an inaccurate idea of how loud they'd be, what frequwncy they'd be -3db down at etc... Each chamber of the subs has 4 triangular ports measuring 11cm high x 12cm wide x 37cm deep (port length). Plus ive properly caluclated the internal volume of each driver chamber and it's 120.5 litres taking off for ports, handles, bracing and the driver depth.

So the RCF LF18P300 would be great in the Wharfedale sub enclosures, yes ok they might not give much extra output but the sound quality would be better using RCF drivers and the excursion is way more than standard drivers in the enclosures. Plus not to mention RCF drivers has excellent power compression figures wheras Wharfedale's drivers have quite high power compression. I know this because the spl very slowly drops quite a bit over say a half hour perdiod which is obviously power compression.

Using RCF LF18P300 drivers the subs in total with two drivers being used (i've been calculating for one driver in one sub chamber) would be -3db @ 34.5hz, the suspected spl output (excluding power compression of the drivers) of each sub would be 130db powered by 1,000 watts average power to each driver. I'm probably gonna load both Delta 218 subs with RCF drivers and then use bridged QSC PLX2502 or maybe RMX2450 amps on each sub so I have a little headroom.