Greetings all.. 
I have an old 4 track demo with some drums on it that I was hoping to "drum replace" and have been hitting my head against the wall. The track is actually drums recorded with overheads mostly.. We didn't have multitrack capabilities, many mic's, mixer etc back in my youth. We were fortunate enough to have a Yamaha 4 track recorder..
 
So the drum track I want to rescue is essentially an overhead.. and I've been trying to extract the kick/snare from it to import into some modern "remakes" of the material. I've watched tutorials and read info and somehow I can't get it to extract the part reliably. Most if not all the tutorials use mutli-tracked drums which are largely one drum per track and triggering the hits is largely a piece of cake. I just can't seem to zoom in.. I suppose I could manually "paint" the markers in for the whole track.. but that is very time consuming. So far I've tried using "EQ" to HPF, LPF and boost/cut to try to narrow the range to get Drum Replacer to lock in, but it's a messy result.
 
I was hoping someone maybe had some great tips or suggestions as surely I can't be the only person in Sonarland with this desire. I've tinkered with Slate Trigger and AD Trigger as well.. but haven't had any luck with their demos either.
 
Thanks!

Is the original drum track isolated (only drums)? Drum enhancement has been around forever similar to embellishing existing material via MIDI triggered clones.

But, if you have an isolated drum track... Replacing that can also be achieved by offloading the tracks track-for-track, then setting the project tempo map using Shift-M (set measure/beat at time now). Quite a few posts on that specifically. Once complete you can try extracting the MIDI to drive a VSTi, or simply replace the track with a VSTi from scratch (either substantially lower the original or mute it entirely).

Once you have a tempo map set, there are a lot of options available.

Drum Replacer is essentially a combination of the above - MIDI extraction and MIDI fired replacement.

I've done a lot of restoration work on old 4 track mixes and the flux in speed is possibly the worst offender (the capstan motors). however, you might opt to redo the whole drum track if its isolated.
You can use Melodyne to extract the tempo or if you can manually tempo map it, Which is a chore.
 
If your drum track is an ISO track (just the drums using that overhead you spoke off) you can probably extract some of the pieces using DR. use the filter knob to zone in the frequency's of each kit piece.
 
Like I said, if worse comes to worse, redo the track using session drummer or the equivalent.
Its a great way to bring old dull tracks to life.
 
 

I didn't see anything in the OP about tempo. As I understand it, there's an overhead mic recording and the OP is trying to reliably get kick/snare hits from it. Correct me if I'm wrong.

I don't know if you've tried using the filters and thresholds in drum replacer but they work pretty well for me. Try setting the kick filter to somewhere around 100Hz and the snare around 500/600Hz. Of course it depends on the drums and recordings but these seem good starting points for me generally. Next use the threshold levels to find a point where you get all of the hits you want and none of the ones you don't want. If you can't find such a spot, better to have a few extra hits. You can then drag the clip onto a midi track and load your drum VSTi of choice. Edit out the few extra hits with the piano roll editor.

Disclaimer: Drum Replacer is an awesome addition to Sonar but I haven't has much success with it.
 
So I took this for a spin: I opened a new project and imported a drum overhead track into it after trying to get Drum Replacer to track the kick for awhile with little success I thought I would give Addictive Trigger a shot. I loaded AT into the FX bin, set it to kick, engaged the Superstart, hit play and let it do it's thing. It finger printed and tracked the snare perfectly so I set the fingerprint to ignore the snare and I had the kick tracking perfectly.
I cloned the track and repeated the process with AT set to snare. No fuss, no muss, I got the snare tracking perfectly. I'm sure I could have done the same with toms but in true Monday fashion power went out to the building where I work so I had to tend to my day job.
If I knew a good way to replace Hat and cymbals I would tell ya. So far I like Chuck's solution but it takes creating a tempo map which is pretty easy: https://www.youtube.com/watch?v=M_SKmr_07Is
 
Rocky
 

+1 for Sanderxpander's  post above Templegates. I have had great results for the most part following exactly this method.

Thanks for the report on Addictive Trigger, Bluzdog, I had been wondering about it. I've had pretty good success with Sonar's Drum Replacer but the Addictive Drums library integration is pretty tempting, I have a bunch of kits. I'll keep an eye out for a sale.

 
http://lesound.io/product/grooveextractor/

Sanderxpander
Thanks for the report on Addictive Trigger, Bluzdog, I had been wondering about it. I've had pretty good success with Sonar's Drum Replacer but the Addictive Drums library integration is pretty tempting, I have a bunch of kits. I'll keep an eye out for a sale.

 
You're welcome. That's what sold me on it as well. I have all of the AD Paks. It pretty intuitive especially if your used to AD2. I paid $74 when it first came out. I've been a long time fan of Slate Digital Trigger but it I couldn't see buying the same samples twice for the ability to use them in Slate Drums.
 
Rocky

bluzdog
 So far I like Chuck's solution but it takes creating a tempo map which is pretty easy: https://www.youtube.com/watch?v=M_SKmr_07Is
 

4 track tapes are a totally different animal compared to digital recording.
The capstan motors fluctuate in small increments so much that mapping the tempo can sometimes be a chore.
However IMO, its easier than trying to restore an old crap drum track.
Even with a song straight 120BPM's. the flux (which is also called: "Drift") can be anywhere from 0.2 to 0.7%.
 
Last month I rebuilt 8 songs using this method. All Drum tracks were totally replaced (creating a brand new drum track from scratch).
Tempo was mapped (some songs were easier than others) Existing tracks included Bass, Guitars and vocals.
Here is one of those projects: https://soundcloud.com/charlie-roy/seven
 
Once a foundation is established, layering of new tracks can be added with ease because the project lines up with the grid. In this song above, I used the original Bass, Guitars and vocals also added was Synth bass and more background Vox.