where is TAP TEMPO in X3d?

You need to use - Process>Fit Improvisation.

I've never used that mouse driven option myself. I find it easier to input a 4 beat click to the song via my midi keyboard then do a Fit Improvisation.

Though unofficial, Duckbar has a handy tap-tempo tool in its toolbar.

I like that, Brundlefly. Nice one!

bump for a step backwards burying the tap tempo in the menus. :( That's the second thing you do after, ' what's the name of this one'.... 'about how fast' , keep tappin and singin, I'll get to the tap tempo in a bit. As for clicking with the mouse, they register when you let up on the clicker as opposed to when you click down. So try to be steady when letting up on your mouse for a better tempo measurement.

brundlefly
4/4 Time: Space, <-2-3-4-2-2-3-4->, Space, Shift+M, 3, Tab, 1, Enter, W
 
7/8 Time: Space, <-2-3-4-5-6-7-2-2-3-4-5-6-7->, Space, Shift+M, 3, Tab, 1, Enter, W
 
Look, Ma... no mouse! 
 
Bind Set Measure/Beat at Now to a single hotkey (S is conveniently close to all of Tab, 1, 3, and W), and you're really cookin' with gas!
 

 
Nice tip!  Thanks.

I play in a couple of bands, one as a duo using a full backing track minus my guitar parts and the other band using a click track on the left channel for the drummer and a mono mix on the right channel to the PA. When I am working on a midi file for a backing track, the first thing that I do is import the song file. I then look for a consistent tempo that can be set so that bars and beats align. When this is not the case I revert to playing the song and using my midi Kawai keyboard, tapping in a click on a new midi track and then using it as the source for 'Fit to improvisation' which adjusts the tempo of the 4/4 click to keep the bars in line with the original song. With that done, my click track is deleted. Once I've finished programming all the midi tracks I can delete the original song and usually at this stage edit the tempo track to one consistent average tempo before bouncing everything down to an audio track. This has been a reliable way of working for me and I would shudder at the thought of using my mouse to input the clicks. It's a breeze once you get used to it.
Pete.

petgod1
When this is not the case I revert to playing the song and using my midi Kawai keyboard, tapping in a click on a new midi track and then using it as the source for 'Fit to improvisation' which adjusts the tempo of the 4/4 click to keep the bars in line with the original song.

Peter, you should look into using Set/Measure Beat at Now for this as well. It's fast, precise and flexible (you can map intermediate note values where things are changing quickly or nothing for several measures where they aren't), and you're creating the tempo map directly from the audio instead of introducing another layer of inaccuracy in trying to create a matching click track by playing along; you're going tend to play an average tempo around what's actually there when you do that.

Big props on creativity, Brundlefly.  I will try that one out when the need arises.
 
I'm not a huge user of tap tempo, but it seems to me that MIDI Learn capability is a glaring omission here.  Even the long-dead Project5 featured external control over tempo.  Tap in a few select notes, or use Digital Meter to create a CC envelope.  I have an MPX1 with an envelope follower that effectively converts audio into a MIDI controller message.
 
A few chunka-chunks on the guitar and I'm right there.

Ok, 'help' is not clear on using Set/Measure Beat at Now on an audio track or did I miss something? Please give us a clue on how to start without getting the 'unable to specify....' pop up, or a link to a decent help file. Thanks.

Peter, take a look at this post to get started. 
 
http://forum.cakewalk.com/FindPost/2922802
 
The exact steps depend on the material, and how variable the tempo is. Working with freely-recorded MIDI is especially easy because you can easily spot the note that's on the beat you want to Set, and you get perfect accuracy by tabbing to the note start. With audio it can take a little more time to figure out which transient is the one you need to Set, and getting the Now time right on the transient if Audiosnap didn't do a good job of detecting it. I tend not to use it as much as I should, but scrubbing may be helpful in either case.

It works that same way, but you're tabbing to transients instead of MIDI notes (and maybe having to tweak the Now time to get right on the attack in some cases). Here's another thread specifically referencing audio. The OP never responded back, but I have a project with his audio that demonstrates the outcome of the steps I outlined in the post if you want  to see it. Note that this post was in the old SONAR forum, so the command was Ctrl+M instead of Shift+M
 
http://forum.cakewalk.com/FindPost/2943794
 
 

Tell me about it. Obviously one does not get to 8k+ posts while making music. 
 
Songs forum: http://forum.cakewalk.com/Songs-f27.aspx