I should maybe have mentioned in my original post that I have tried sending one of the kick sounds/tracks to a reverb and low-pass combination. However, still this doesn't quite seem to get the same sound.
Like I said in my original post, the thing I can't seem to work out is how the pitch of the bass/low-end rumble (the kick with reverb and a low-pass filter on it) seems to be changing so much when the source just seems to be a kick drum sound of different volumes or perhaps different velocities.
This pitch difference is in both the tracks, but is perhaps more clear in the second one.
Sometimes you have to think out of the box a little. I don't know how 'he' does it but I know how I have done similar things and the results are very similar.
Essentially, what you are trying to do is better done with resampling, it offers way more control than gated low passed reverbs and heaps of efx chains.
A 'not-so-well-known' app called Paul Stretch will be your friend here but be prepared for a bit of groundwork first. A lot of people just make ambient sounds with the app but it will also do great stuff with drum sounds if you have a bit of insight. You are going to be stretching the sound of a drum to oblivion and then recording the result and then using the sample you made in a sampler with an applied envelope. Here's how:
1. Record/bounce out a solo 2 bar kick loop. Not just any kick, it HAS to be the kick you intend to use for the track, you'll see why later.
2. You need a few bars for Paul Stretch so it gets fed enough info. Use default settings but change the stretch mode to hyper stretch and move the slider to something like '3 days'. When done correctly, you should just hear the kick stretched to oblivion making an endless bassy, noisy drone. This is your raw sample. Either record the output into an editor ( I record from it directly into Wavelab ) or make a wav from the app. Call it 'kick 1 stretched' or whatever the name of the kick is.
3. Open your daw and drop the sample you made in a sampler. Whatever your kick pattern is, mimic it but make each midi note sustain until the next hit. Now you should have a very raw and rough 'gated' sound and it's here you will need to tailor it to make it sound great.
4. Reduce the samplers polyphony to 1 note so there is no overlap from any release time and adjust the ADSR to suit, I usually make the attack softer and fiddle about so there's no clicks in between the hits. Your sample should be at least 10 seconds long which will give you plenty of material to play with so find a nice spot by experimenting with the samples start time. This technique usually doesn't bring about any phase issues as its essentially the same frequencies but it's possible some will occur depending on your sample start time so experiment with that.
5. Once you have everything tight, it should sound very similar to a controlled 'gated reverb' sound with the stretched kick giving that decay/bass sound. Here, it will be in stereo so you are going to need to experiment with a plugin that controls stereo spread and you'll also need an eq and/or a filter but more on this below.
That's you basic sound and it's then up to you as to what you do now. When I have done this, I have made 2 instances of it and hi pass filtered one of them at about 300hz to 500hz and left the stereo information in and I have low passed the other one at the same frequency of the hi passed version and made it mono and actually bounced it out again to a single sample. You can also experiment with the pitch too, maybe add a 3rd copy of the sample and make it +12 or +7 and mix it in and eq it to fit.
If you have done all this correctly, you will end up with the same type of sound. No idea how Regis made his but often in the world of music production trickery, people find their own way of doing similar things. The reason why this works is that you're using the same source sound and it's the exact same frequencies albeit stretched. It's way better than trying to make decay from reverb and then f_cking about trying to control it and get it tight. This way gives you the actual sound not an ambient representation of it, just control it with ADSR settings, eq, stereo width control and 1 note polyphony. Experiment using other drum sounds to in the exact same way. Claps, hi hats etc, layer in a stretched version of itself and create tails which you can blend in at a low level giving subtle depth to any sound really.