I would say, for Ivory II : a ssd, AND a powerful computer.

Mine has a ssd, but is a little old now (Core 2 duo at 2Ghz, Windows 7 4 GB ram).
I cannot play without glitches Ivory, so I don't use it anymore and play now with Galaxy Vintage D, it's much less consuming I haven't problems now.

Yes. I bought an external drive enclosure with a Firewire 800 and USB 3 port and dropped a 256 GB Samsung 840 SSD in it. It took about 10 minutes to assemble and it works perfectly. If you are concerned about cost that is a pretty inexpensive way to go. Get the Samsung 840, not 840 Pro, to save money. The 840 is perfect for this application because you will seldom write to it so wear out isn't an issue.

Firewire 800 is fast enough for Ivory II with room to spare (you need an SSD for its fast random access reads, not a faster drive interface). But USB 3 is there if another piano comes out that needs more bandwidth. I don't see a future in Thunderbolt for this (or many?) application. USB 3 is much less expensive, plenty fast enough, and will be ubiquitous. All current Macs (except the now 3-year old Mac Pro) have USB 3. I'm waiting for the new Mac Pro (expected this summer) before replacing my current piano iMac. (Yes, I'm an engineer and love tech stuff. Fortunately I can afford it.)

yeah, i'm one of the folks that has a 3 yr old macbook pro. so no USB 3. but i do have firewire...

thanks for the input on the 840.

Is there something about Ivory 2 that makes it more resource-demanding than Ivory 1, or than the various Galaxy pianos? My old laptop ran fine with Ivory 1 and with the Galaxy items, despite its paltry 1.7 GHz Core Duo, 2 GB RAM, and 330 GB/7200 RPM drive under Win XP. So whuzzup with Ivory 2?

I recently moved to a 2.8 GHz i7-940 quad-core, 8 GB RAM, 1 TB drive. Will Ivory 2 run on this box? Or do we all need to move to SSD to run Ivory 2?

I never had Ivory 1 so I can't compare them. But the Ivory II American D definitely required a faster (faster random access) drive than the previous Ivory II pianos. It's samples are longer, but the Ivory II plug-in and standalone (Mac) engine were also changed when it was released, so that may also have something to with that.

In my experience (and measurements) the Vintage D takes a lot more CPU than Ivory II (perhaps because the Vintage D samples are compressed and have to be uncompressed in real-time, or Kontakt is just CPU hungrier than Ivory II). But the Vintage D is MUCH less demanding on the drive.

So do you need an SSD with Ivory II now? Synthogy (Ivory II developer) says minimum requirement is a 7200 rpm drive or SSD, connected via Firewire 800, SATA, or faster. I'd say the 7200 rpm drive is now on the edge unless you want to limit the number of notes you can play at once.

Using Ivory II with a Core 2 Duo laptop (T7300, 2 GHz, 4 GB RAM - handful of years old), Win 7 SP1-64 and an external Lacie FW HDD (7200 rpm). Works perfect in tandem with am RME UC interface.

I do recall upgrading my laptop HDD a few years back to a faster spec SATA . . . uncertain to what degree that would affect things.

I had my hard drive replaced in this laptop. It's 72 or 7800rpm. It's a PC.
Still... I just now had the notes drop when holding down four of them. Was playing something not complicated. Yes, two hands. No big deal. The software shows the info coming from the midi controller keyboard.
If I change settings on my keyboard. I also have to restart Ivory. Otherwise, nothing. And it still shows info coming from the keyboard.
I only once had the pop and crackle bit. Restarted and ok.
I got my eyes on a new Mac. By the first of the year. SSD is at the top of the list.

yeah- i have a 7 yr old dell core duo desktop with a second 7200 RPM HDD for samples and it runs ivory II perfectly. i think i have 8 GB RAM (or maybe 16? whatever the max is for that box...)

i think the conclusion to all this is to either have an SSD on a laptop and basically just have it dedicated for pianos. OR, get an external HDD for a laptop and a second HDD or external device for a desktop. i just think as long as you don't get operating system stuff interfering with the HDD feeding the back end of the sample you will be fine. I've never had any problems with Ivory II/ Cantabile player. I have had some issues with Kontakt- not deal killers but it just doesn't run as smoothly for me- probably gets back to Macy's very perceptive post just above- my older box RAM access might not be as good and that penalizes Kontakt use over Cantabile use....

Agreed, but I don't even see the need for a second drive or SSD ... as long as you dedicate the box to piano, and shut off the non-essential/overhead junk.

I used to run pianos on my 7-year-old Dell crappy laptop. It was marginal, but worked fine as long as I disabled AV and wireless ... and ran nothing but Kontakt. But if I turned on wireless and started up Firefox, the piano would hiccup. If I ran anything more intense than a browser, the piano basically fell apart.

OK, but all that was with a ghetto laptop.

I recently moved, and the new home has no space in the living room for the piano. So I put the piano in my office ... next to my much newer HP desktop computer. So I no longer use the laptop. I loaded the desktop with all the piano software.

I can load a bunch of pianos (with AV still running) alongside all of the regular desktop assorted apps. Another person can use the computer for normal stuff while I'm playing the various Galaxy pianos through Kontakt ... and no problems.

That's with a 3-year-old desktop, a 2.8 GHz quad-core i7 930 with 8 GB RAM, Win 7, and a plain old 1 GB 7200 RPM internal drive. No SSD. No external drive.

If I were running a DAW and were doing things that heavily taxed the computer, maybe there would be problems. But for JUST piano(s)? I have to wonder why Ivory 2 would not work here.

MacMacMac, it probably would work fine on the single hard drive. i just found a 7200 HD for peanuts on amazon and wanted to prove to myself i could install a second drive and some extra RAM. really nothing more than that. one of those tool-time projects.