I’ll try to tl;dr this – I had similar issues with Alchemy & a Mirage a few years ago. I narrowed it down to something in the middle of (1) being on PowerPC instead of 68k and (2) using the Alchemy OMS driver instead of direct serial MIDI.
Alchemy & Mirage & 68k & basic serial MIDI:
Alchemy & Mirage & PPC & OMS:
I suspect there’s a bug (off-by-one or bit manipulation error?) or timing issue somewhere in the plumbing of 68k-emulation vs PPC-native code between Alchemy and OMS. (I may, or may not, have verified this at the time by using Alchemy in OMS mode on a 68k and finding it worked – but in this config, kind of irrelevant to use OMS when using a basic serial MIDI interface and no OMS clients.)
On PPC with OMS, it was very reproducible that the first ‘page’ (256 bytes?) of Mirage sample data would disappear or corrupt, if I simply did a ‘send to Mac’, & then a ‘reverse’ operation, followed by a ‘send to Mirage’. The only 100% remedy was to use a real 68k Mac. By that time, I also preferred to use a basic serial port MIDI interface, because the variables and settings involved in using multiport interfaces added additional annoying & sometimes unreliable complexities (I remember some ‘direct mode’ setting with a MOTU Timepiece AV…), and because my Opcode Studio 5 blew up. I wrote this up around that time (the top part refers to the Opcode Studio 4, and probably has little to do with this problem):
midi interfaces and computers used/tested
Because of the amount brainspace this (still!) occupies for me (and masochism), I would still like to try this with a beige PPC desktop/tower Mac (with built-in serial ports) but I don’t have access to one right now (I currently have a surplus of beige/Snow White 68k hardware though). The reason is:
- PowerBooks (68k / PPC) will always drop power to the serial port when it’s not in use
- these early programs don’t ‘turn on’ the serial port when using their ‘native’ (non-OMS) MIDI drivers
- OMS will [optionally] keep the MIDI port / serial port open/awake on PowerBooks; this may (or may not) require keeping an OMS-aware program running (with the ‘keep MIDI ports active in background’ turned on)
- On real desktop Macs, the serial ports are ‘awake’ all the time
- OMS’s “Preferred Device” is the means by which OMS supports MIDI for non-OMS software
…but in my experience (if I recall correctly) using OMS & Preferred Device on PPC PowerBook is subject to the same bug I started this post with (lost/corrupt page of Mirage data).
ps - I Sample Wrench, it just doesn’t support Mirage.