In addition to the good information thatβs been offered so far...
Iβve recorded maybe two dozen pipe organ live performances, mostly three different organs in three different venues. That doesnβt make me an expert by any stretch of the imagination, but reading through your post I just kept feeling the urge to say a few things and make a few suggestions...
SEMI-PROFESSIONAL EQUIPMENT
Iβm a real believer in βbuy once, buy rightβ, but for recording pipe organs that approach usually means mics from DPA, Schoeps and others that have excellent off-axis response - which is necessary because the room is such a big part of the organ sound and it should be considered part of the organ itself. Those mics are expensive, and if theyβre not affordable for you then the next step is to buy something affordable that wonβt seem like a huge waste of money if it turns out you donβt enjoy recording pipe organs, or youβll still be happy to own if/when the bug bites and you decide to spend more.
With that in mind, Iβd suggest the following...
1 x pair Rode NT6s with the optional NT45-O interchangeable omni capsules. The Rode NT6 with the omni capsule punches well above its weight, and the NT6βs smaller body gives it a better off-axis response than the NT55 itβs derived from. The last time I looked the graphs look the same on Rodeβs website but I suspect the web designer used the NT55 data for the NT6 as well because it is the same mic in a different housing.
Anyway, the combination of NT6 pair with cardioid and omni capsules means you can use omnis or cardioids, so you can do AB and you can also do all the near-coincident techniques that rely on spaced cardioids (NOS, DIN, ORTF, et al). The other benefit is that you can place most of the weight of the microphones (their body and XLR connectors) further down the microphone stand, which is important for stability when using a tall stand (as is often required for miking pipe organs).
http://www.rode.com/microphones/nt6
http://www.rode.com/accessories/nt45-o
To go with the Rodes, Iβd suggest forgetting about interfaces and computers and so on and got a Zoom F6. Itβs a super portable stand-alone field recorder that can also serve as an interface. It has a 32-bit float recording mode so you donβt have to worry about getting the recording levels right, and if youβre in a hurry or in a venue with an audience you can place it at the bottom of the microphone stand and not have to worry about running cables all around the place without risking injuring people...
https://www.zoom-na.com/products/fie...field-recorder
Get a Manfrotto 1004BAC stand. Itβs lightweight, it goes up to 3.65m, itβs black, and itβs air-cushioned which means when you loosen off the clamping screws it slowly slides down rather than dropping down suddenly. Apart from protecting your gear, it looks super pro in action. I used these a lot and made a point of letting the stand slide slowly down while the audience was still milling around the room. People see the mics slowly and gently gliding down while Iβm winding a cable or something and it looks very impressive. They immediately assume youβre some kind of professional and before you know it theyβre asking your rates and offering you work.
https://www.manfrotto.com/global/pho...ioned-1004bac/
To go with the 1004BAC, get the extension arm Manfrotto make for it. I cannot find it on their website, but itβs essentially like adding another 1004BAC on top of it, but without the legs or air cushioning. I used that quite a bit for organ recordings when I needed to get higher. There are some caveats with it, but itβs not a bad idea. Youβll definitely want a few 5kg shot bags to keep all of that stable, however.
For a stereo bar, I can recommend the simple and elegant Basic AB from mic-bar.com. It weighs almost nothing, looks great, and will let you space your mics out to at least 50cm apart for those times when you want to use the AB50 technique.
https://shop.mikrofonschiene.de/Basis_AB
I wonβt recommend cables because thatβs a fairly simple thing but depends on your needs. If you intend to set up in a separate room for isolation, youβre going to need very long cables if youβre recording live performances with an audience. If you intend to record yourself and operate the gear from the organ console, youβll need cables to reach that far (or choose a recording device you can leave at the bottom of the mic stand and control with Bluetooth or similar from a smart phone or tablet). The only thing I will say about cables is use a single stereo cable, like Manfrottoβs 2930 or similar. Why run a cable twice when you can run it once? It is exhausting and time consuming running cables under carpets and along the edges of walls in churches and similar public spaces. So it is better to only have to do it once...
Iβm not going to recommend any headphones; thatβs like recommending monitor speakers and running shoes at the same time. Not only do they have to sound good to
you and bring
your hearing into focus, they also have to fit
you well. And then thereβs also the matter of whether you need isolation because youβre recording from in the same room (closed back or canal phones) or if you intend to record from another room (in which case you could use open back).
There will be a bunch of little things youβll need to take care of as well, like velcro, black electrical tape, a tape measure (for taking notes of distances and heights to do it the same or better next time) and so on...
OTHER THOUGHTS
Please donβt get fixated on those distances youβve mentioned, 5m and 8m. The right distance will change depending on the organ/room, the piece of music, the performerβs interpretation of that music when played on that particular organ in that particular room, the mics youβre using, the technique youβre using them in, the amount of external noise, and the aesthetic youβre aiming for.
If I had the rig I suggested above or something similar, hereβs how I would go about it from a methodical/strategic point of view. You may or may not get a good result this way, but if you donβt get a good result you should be able to figure out why and do it better next time...
1) Start with the stand at a reasonable height, say full extension of 3.65m. Place the two mics on the stereo bar side-by-side, facing forward, with no space between them.
2) Experiment with the distance until you get the desired balance between the sound of the pipes and the sound of the room.
3) Fine-tune height to get more or less articulation from the pipes.
4) Now that you know the desired distance and height, you can put the mics into the desired stereo technique. I like AB for pipe organs, and I like to have them widely spaced for a spacious image - although thatβs not always possible. So if I was using omnis and going for AB, Iβd start moving the mics apart. Somewhere between about 35cm and 50cm apart you should find what youβre looking for (although some people would recommend 60cm). Check in mono to make sure itβs not falling apart and you havenβt got too much room sound (if it sounds buried in reverb when heard in mono, youβre too far away).
5) With all of that done, you may find you want to tweak the distance, height or angles further. Do it.
6) When doing this, itβs also important to know either what
you or your client like in a pipe organ recording, or what will
serve the music the best. For some people and for some pieces, a big reverberant spacious sound is the main criteria. For others, itβs all about βthe dance of the pipesβ - they want to hear the sound moving around in the stereo image as the different banks of pipes play different parts. If you can get both... winner winner chicken dinner!
I hope thatβs helpful...