OK, I haven't written a review of these yet, but I will start formulating a comparison here, hard to know where to start so thanks for the question.
Width of sound stage 1plus2 vs IQ 9. The comparison is difficult to make as I find the IEM's do very different things. The IQ 9 I find can throw extremely wide, but to me now it is like it is throwing to a location that has a lot to do with time rather than distance of the instrument or sound. It is like the IQ 9 has a sound stage so wide that sometimes it almost throws to a point where it separates it from the music. It is a tiny bit out of control with it. I think that this is exciting in itself, and certainly makes up part of why instrument separation on the IQ 9 seems to be really clear also. The IQ 9's sound stage is very lateral I find, impressively so, but it is lateral. The 1plus2's are a completely different story.
The review or comment I most identify with at the moment about the 1plus2 is how amazingly similar it is to sitting in front of high end speakers. So I think frontal would most certainly be right. The Sound stage is not necessarily as wide as the IQ 9, it isn't as if the helicopter flies from ear to ear and Doppler effect off into the distance as it would on the IQ 9, it flies in the medial sense also.The1plus2's sound stage is as deep as it is wide, and this I think is partly what makes it so astonishing as an IEM.
The IQ 9 is wonderfully clinical, I like it, I like hearing the precision, I like the ultra wide sound stage, and the absolute instrument separation. It is a sound signature that I haven't heard before, and one that I enjoy. However the IQ 9's certainly present the music in its constituent parts very well, which is great, but it is different from the Tralucent 1plus2's. They present the music totally differently, they present it as an orchestra would to my ears, all genres seem to get converted into something else and it is all very very musical. Incredibly for an IEM it totally envelops you and it truly feels as if you are listening to some kind of massive surround sound system. That is what the sound stage is like to my ears on the Tralucent 1plus2's; a huge sound rig.
The IQ 9's seem to place sound spatially, the Tralucent 1plus2's seem to allow it to travel spatially. That is a huge difference to my ears.
I have them in now and am listening as bass swells sound like they are coming from behind me on the ground and departing through the top of my skull on a horizontal plane.
I absolutely agree with the reviewer that the 1plus2 is unique in sound staging, and I am glad I have the IQ 9, a hybrid also, for comparison. However I say that it is unique also, and impressive.
It is like the Tour De France...you know, a sprinter might be great, and really fast and great to watch...that's cool...and all of those things...
He is never going to win it though as he isn't suited for climbing mountains. Doesn't take away the stage wins and the excitement he brought to the race, but everyone wants the yellow jersey really, right?
More to come from me writing wise on these 1plus2's, a proper review, but I think it is about time I started to get some notes down, and being prompted with questions is always useful.
I cannot see a bass vent truckdriver. I work in noisy environments sometimes. I had them on at a low volume in the engine control room of a very large ship, admittedly it was the control room, but there is still a good rumble down there. Could still hear everything just as I could when at my desk.
Great "pre" review. Looking forward to the proper one from you. The 1plus2 sounds very interesting.