What is your max budget for that ?

The combination of RayDAT and Ferrofish Pulse 16MX is surely nice. It will definitively give you a great value for a not too high price. Possibly also nice for you as the Pulse 16 supports an equal number of inputs and outputs, if this is needed.

But if you do not intend to use MADI I would take the Ferrofish Pulse 16 without MADI which is €200 less expensive.
AFAIK the Ferrofish can be upgraded to MADI for exactly the same price (€200) if you need it.

At any later time you could even add an ADI-2 Pro FS R BE to the AES port of the RayDAT to get all the very nice features of the ADI-2 Pro for your minitoring section and by this you would even get a SRC (Sample Rate Converter) converter into your setup, which can be useful when connecting devices with a fix clock and that are unable to be clock slave.

The question is, whether this combination gives you everything that you need and is kind of future proof.
Should you intend to record at double speed then the RayDAT would be full with the Ferrofish Pulse 16.

As the Ferrofish Pulse 16 MX also supports MADI you could also think of an extremely nice combination of UFX+ and Ferrofish Pulse 16 MX via MADI.

The advantage of the UFX+ is
- three possibilities to connect to a PC: USB3, Thunderbolt (external PCIe) and USB2 (without MADI)
- four excellent MIC preamps with 75 dB gain range, can be switched to act as INSTR input as well
- 8x analog I/O independend of any samplerate
- 2x ADAT I/O, ADAT2 switchable to support optical SPDIF
- 1x AES I/O
- 2x MIDI I/O
- Word Clock
- MADI optical and BNC (by using WC connector, switchable), also split mode possible 50:50 optical/bnc
- Standalone recording and fully operateable through the display or TM FX application with iPAD
- DURec - Direct USB recording to USB disk/ssd or pen drivers for standalone or backup recordings in addition to DAW
- AUTOSET - to quickly find a proper mic gain with -6dBFS headroom and for automatic gain reduction preventing overloads
- two excellent phones outputs
- ARC USB can be connected to a dedicated USB port at the back of the device (useful in stand-alone more)

The advantages of an ADI-2 Pro you can see here and in the 2nd blog article how to integrate it into your setup:
https://www.tonstudio-forum.de/blog/ind … ses-EN-DE/
https://www.tonstudio-forum.de/blog/ind … our-Setup/

MADI support 8+ devices on the MADI bus. The devices can be chained to a serial ring structure.
The MADI cable between each of the devices may be up to 2km long.
This supports even structured cabling in a house using OM3 or OM4 multimode cables.
So if you would plan to have different recording rooms in the future this would be much easiert possible with MADI,
because then you can place devices with mics/phones into every room more easily.
Just to give you a vision about the flexibility of a MADI based setup.
If you do not want to implement structured cabling, OM3/4 patch cables with the proper plugs at each end are available from 0.5m up to approx 50m which gives you a great flexibility.

I think something like a very flexible "dream setup" would be something like this.

I do not want to claim that it's ideal for you, but I wonly wanted to draw whats possible with RME.
Think about price and features and then narrow down, whether this or parts of it might make sense for you or use the RayDAT as a base:

- UFX+                                                           €2799 (Thomann bundle with ARC USB)
- ARC USB                                                      included in the Thomann bundle, see above
- Ferrofish Pulse 16MX                                  €1169
=====================================================================
Base Price                                                      €3968

- ADI-2 Pro FS R BE                                        €1689 (optional)
- Sonnet Allegro (USB3-4PM-E)                      €    55 (optional, if needed to isolate UFX+ on dedicated USB controller)
=====================================================================
Optional components:                                   €1744

TOTAL:  €3968 + €1744 = €5712

PC or Laptop or stand-alone
|
| (USB3 or Thunderbolt)
|
UFX+---------AES/ADAT---> ADI-2 Pro FS R BE --->monitors/phones
++++
| | | +--------USB----------> USB Stick (DURec)
| | +----------USB----------> ARC USB (alternatively: connect it to the PC)
| |
| | (MADI, optical OM3/4)
| |
| + Ferrofish Pulse 16 MX (for recording in single/double/quad speed)
| |
++

Alternatively the RayDAT based solution

- RayDAT                                                        €585
- Ferrofish Pulse 16                                       €969
=====================================================================
Base Price                                                      €1554

- RME WCM HDSP 9632                                 €109 (optional: Ferro can be clocked by ADAT)
- ARC USB                                                      €129 (optional, for more comfort)
- ADI-2 Pro FS R BE                                        €1689 (optional)
=====================================================================
Optional components:                                   €1927

TOTAL: €1554 + €1927 = €3481

PC
| |
| +----------USB----------> ARC USB (alternatively: connect it to the PC)
|
RayDAT ----ADAT1-2 (or 1-4) ------- Pulse 16 --- Monitor / Phones
|
| optional:
|
+------------AES----------------------- ADI-2 Pro FS R BE ---- Monitor / Phones

> Thank you for your reply. I'm really trying to keep it at ~3k for interface + converter.

In this case I would plan for the combination of: RayDAT, Pulse 16 and ADI-2 Pro.

> I had thought of Thunderbolt, but would probably have to upgrade my mobo to do that and
> I don't really want to at this point.

Such an upgrade can be performed at any time later, more important, you have this option
and not only that but also between using USB3 and USB2 (without MADI, as 30ch interface).

As you can see here the performance in terms of low RTL is pretty equal with RME between USB and TB.
See my blog article https://www.tonstudio-forum.de/blog/ind … 8-RME-UFX/ where I put some examples:

> Does the MADI have comparable transfer speed?

Pretty much the same as ADAT, but up to 64ch at single speed and up to 8 or even more devices that can be chained.
Also cable lengths much longer.

> That being said, wouldn't Raydat + Pulse give me same inputs, but at a lower sample rate (48 khz?), right?
>I had thought of the MX because of the flexibility for higher sample rates to future proof it more.
> Saving the money is an attractive option, though.

AFAIK .. Pulse 16 and Pulse 16MX are basically the same devices, except that with the MX you get MADI additionally.
With the RayDAT you can connect the Pulse 16 (or also the MX version) with 4 TOSLINK cables in each direction
and have 16 channels up to double speed (88.2/96 kHz).  But then this card is full.
MADI allows you up to 32 ch at double speed and longer cable lengths.

In your case I would either go MADI with an UFX+ and Pulse 16 MX and then get later ADI-2 Pro at any time.

Or you get this combination:
- RayDAT                                                        €585
- Ferrofish Pulse 16                                       €969
- ADI-2 Pro FS R BE                                        €1689

And with that you are very close to budget with €3243 (only a little more).

But the you have directly the ADI-2 Pro FS to enhance your monitoring section.

> Ok, thanks. It looks like MADI is the fastest

Not exactly. Am not sure whether you compared the values in the proper way.
1. For UFX and UFX+ you can use the values in the 5th column "Summe Latency". These are the values that the driver reports to the DAW which you can see in the ASIO settings under input and output latency. And this includes the latency for A/D and D/A.
2. The second use case was the RayDAT, where I connected an UFX as preamp. In this case the DAW only tells you the latency values for the transport over PCIe. You need to add the converter latency for A/D and D/A manually to get the full RTL (round time latency). This you can see in the 6th column "UFX connected to RayDAT +0,9ms". And on the right side I added a screenshot from the UFX manual which show the latency values of the converters for A/D and D/A for 44.1 kHz to get compareable values.
3. The third use case was the HDSPe MADI FX. Here you need to add the converter latency for the Octamic XTC which is connected through MADI. The digital transport over MADI you can omit to make it simpler. Here you need to look into the 7th column "Octamic XTC connected to HDSPe MADI FX +0,91ms".

The different bandwidth of USB2/USB3 or ADAT/MADI make it possible to send more channels through it.
Therefore you can send more channels through MADI (64ch) compared to ADAT (8ch).
But this doesn't give you a lower latency.

You use MADI for the following reasons:
- more channels
- longer cables
- Higher sustainability of the investment with regard to later expansion possibilities
- ability to serially chain devices to a ring structure, can be useful to place e.g. preamps to different rooms
- makes it possible to e.g. add an UFX or UFX+ to act as a backup recorder by simply adding it to a MADI chain
To use extended RME MADI features like
- MIDI over MADI to be able to remote control RME preamps without the need for MIDI cabling
- Delay compensation up to Auto ID (automatic ID detection), Auto CA (automatic channel assignment) for the older MADI devices following an 8-port schema like Octamic XTC (but not 12Mic) to put one example.

And if you look at the HDSPe MADI FX then you get e.g. the following add-on features
- three MADI busses, optional daughter card to get the 3rd port as optical as well.
- Redundancy Mode (other two MADI ports act as failsafe input, can also be used for port reduction to 64+2(AES))
- Mirror MADI1 Output to MADI2/3, redundancy for output) reduction of channels to 64+2(AES)+2(phones)
- resource saving ASIO driver that divides all I/O ports into groups of 8 and only allocates resources if at least one port of such a group of 8 is active.

So if you do not need Mic ports, AUTOSET, DURec, standalone-capabilities, then you could also take an HDSPe MADI FX into account. This is the only RME PCIe card which has a FX chip implemented to have FX in TotalMix FX. But this has a price tag, the HDSPe MADI FX costs €1489.

I think with a RayDAT based solution you save most money and when you record in single mode, then you need to connect the Ferrofish only with 2 TOSLINKs for inputs and 2 for outputs. Then you still have 2 ADAT ports IN/OUT free for other purposes.

Next best in terms of cost is IMHO the UFX+ giving you great flexibility. The Ferrofish you can connect by MADI and then you have plenty of other ports free for other purposed and a lot of features that I already mentioned.

The HDSPe MADI FX is for cases where you might need different MADI busses due to number of devices to connect, esp if you record at higher sample rates or in cases where you need to separate/split devices to different MADI ports when the remote control protocols mutually exclude each other: e.g. Octamic XTC Auxdevice vs MIDIremote for other devices.

You're forgetting the realtime component of audio. It works differently than a high-speed download from the internet. You have a constant number of audio channels at constant sample rate and bit depth. This creates a constant data stream and requires a certain transmission bandwidth per second.
You can't listen to a 5 minute song in less than 5 minutes, unless you want to hear Mickey Mouse sing. Audio also can't be buffered arbitrarily, it takes as long as it takes and must be transmitted without interruption. When transferring audio via recording interface and converters/preamps via ADAT/MADI, buffering is almost impossible. For the transfer between recording interface and computer there is only the ASIO buffersize (maybe few safety buffers as well) in the Windows area, but this also only serves to enable an uninterrupted and above all timely processing of audio data on the computer, by this you influence how often the CPU accesses I/O ports for audio processing to have either lowest latency or highest stability (no audio loss). By this you also control the interrupt rate / CPU load, amount of context switches to work on different processes.
Since the transfer speed of digital data over different media (glass, copper) is basically very high, there are also few differences here.
More data could be transferred via thunderbolt, but it doesn't make sense, audio can't overtake itself ...