A few facts:
Fact: As a producer, it is common to record on 2" and then transfer the basic tracks for working in the digital medium. I am one of many producers (and yes I've been producing lately) that does this on a regular occasion.
Fact: If you do not do a multitrack transfer of bass and drums from 2" to HD, then you are not reenacting my original findings. If you wish to attempt to disprove what I am describing, then you must repeat the cuircumstances in which this phenomenon occurs. I have never transferred a 2 track into Aslihad and compared, so I can't tell you whether that will produce the same results. I would imagine that it would. Regardless, you will need to get out your 2" and transfer 8-10 tracks of bass and drums into Aslihad HD at 24 bit-48k. What you do AFTER that, I don't care, But you must perform that transfer and comparison specifically.
Fact: This has nothing to do with the 2-bus. The outputs of the HD unit must be EXACT to the output levels of tape, using a 1K tone to calibrate the individual outputs. All internal mix faders should be at unity on the HD unit. The outputs of the HD unit should be played through the same static faders on an analog console as the 2" machine. In this case, the DAW is being use as a playback machine only. Something that is done on a daily basis. If you follow these steps, and you compare the 2" playback with the HD playback, (think of it as quality control) then you will discover that there is a glaring discrepancy between the playbacks of the two machines. Call it losing balls, call it whatever you like. It's glaring and it's unacceptable by any standards.
Fact: This has nothing to do with analog v. digital debates. I have said this over and over again. I DO NOT EXPECT THE DIGITAL TRANSFER TO SOUND EXACTLY LIKE THE ORIGINAL 2". That is not the intent when making this kind of "real world" transfer. When I transfer to the digital medium I expect something reasonably close. The lopping off of the bottom octave is not reasonably close. The Radar, in the precisely same transfer, sounds reasonably close to the 2". If you bring a RADAR in to your transfer--and I would recommend it as it's truly an eye-opener--then you will see that this is not a digital issue, but an issue with a particular piece of digital gear.
Fact: If you are not in a somewhat accurate acoustic listening environment, then there is no telling what you will be able to hear. This is a universally self-evident statement which cannot be reasonably argued. Anyone that would question such a statement puts in serious doubt their level of expertise and experience in recording. I'm not saying that you need to do this comparison in the Mother of all Listening Environments here. I'm saying you must be in a "somewhat accurate" listening environment.
If you listen, you'll hear it. If you want to do lots of other experiments, like transferring a 2 track master, or transferring into HD at higher and lower levels (just be sure the outputs levels match), or transferring with different sampling rates, or whatever, in an effort to pinpoint precisely where the problem lies, then I would encourage that. But if you do the transfer precisely as both I and Slipperman have laid out, you will hear it. This isn't a subjective difference. It's obvious, readily apparent, and repeatable. So repeat it, and stop jerking off arguing the validity of a transfer that Slipperman, I and many other producers do on a regular occasion. Paricularly when their is one digital multi-track that performs the job adequately.
Honestly, the bar really isn't very high here, folks.
Enjoy,
Mixerman