Hello guys !
Pleaaase really need your help guys i’m lost and don’t have much time 
You need a MIDI interface that supports USB Host (for the OP-1 to plug into), like the Kenton and iConnectMIDI stuff, or an Oplab. The TR-707 can sync with MIDI iirc (it has MIDI In/Out), but if you want to use DIN Sync you’d need something that supports the protocol (like an Oplab, but there are other devices, too, can’t think of any off the top of my head, though). Roland uses DIN Sync 24, Korg uses 48, so don’t get anything meant for Korg unless you want to fiddle with tempo settings 
If you don’t mind using a computer it’s easy to get an audio interface that has midi out, hook the to the midi in of the tr707 and set it to sync, Hook up the op-1 to the computer via usb and put the op-1 into sync mode in the tempo page, hook both to audio ins on your interface and you’ll be good to go! If you don’t want a computer the intern is a good choice. If you don’t need audio in and your running the gear into a mixer then just get a usb to midi interface for the tr707 and use the computer/daw as the clock source.
Thank you guys really appreciate your answers !! What do you thing about using a computer ? Is it really important (i only want to use the op-1 and the TR 707)?
The audio interface i’m talking about
By the way i have nothing else than the OP-1 and the TR 707 (no mixer and no cable for the TR) …
Intern is a typo, meant to be kenton
If you want to record your stuff then you will need to use a laptop and an audio interface. Any with audio and midi will work, it’s up to you on the quality and quantity of ins and outs you need. The one you showed will work.
So in that case why not use the computer and daw (logic) as your master clock?
If you only want to play the op and the 707 how will you mix the audio signals and send them to speakers?
The Kenton will allow you to run The op as master and sync the 707 without a computer.
The you will need a mixer or you could run the 707 into the op’s input and just turn the monitor in on. Op to the speakers.
Hope that is a bit clearer?
Also you will need a 5pin din midi lead for the 707.
Depending on what setup you choose you will either need a 1/4" to 1/4" for the audio interface or mixer, OR a 1/4" to 3.5mm lead to run it from the 707 to the op-1 audio input.
Great thanks adh82 ! And if for example i would like to a reverb do you know how can i process, should i use a mixer or a audio interface with lots of inputs is recommended ? So i will have to plug the OP directly on the laptop if i understand correctly ? Will it be possible to have all the sound in my headphone ?
@realp, check out this thread http://operator-1.com/index.php?p=/discussion/212/post-your-studio-pics-mobile-bedroom-pro-kitchen/p1 for some setup ideas.
Being a visual person, it’s informative for me to look at other peoples setups, so maybe that thread will help out as well.
There are many routes to starting your setup, of course budget, space, and level of time you want to invest are some of the factors, but to briefly answer your questions:
You can simply add reverb from your DAW (logic pro).
Some people use both a mixer and an audio interface, and there are plenty of mixers with USB that serve as an audio interface too. The number of inputs and outputs depends on your current and possible future setup. Do you plan on adding more gear (synths, drum machines, mics,etc.)?
Yes, you can plug the OP-1 directly to your laptop for transferring data and other midi sync features, and while you can drag your Tape recordings from your docked Op-1 to your laptops HD, you could also record the OP-1 through your future audio interface via 1/8"-1/4" cable mentioned above.
Yes, you can monitor through headphones with the Scarlett interface.
Hope the info can get you moving! Have fun and don’t get too overwhelmed 
Thanks for the help guys i finally decides to use this setting without midi syncing ! I was thinking that it was possible by pressing the play button of the OP and the start button of the TR at the same time to sync but i’m having trouble (with the same BPM) any ideas ?
@Realp, The Genie has no MIDI. With the laptop in the picture, you can use Logic for master MIDI sync output. OP1 can send MIDI out but only if someone hosts the USB MIDI party (hence USB host required), and then Logic may be a bit off because Logic. I find OP1’s sync to be loose anyway.
Hi Eesn thanks for your answer ! If i understand correctly i have to use midi ? I was thinking it was possible to sync everything by pressing the start button at the same time with the same BPM but is it really not possible ?
Yes it should be fine without midi,just pressing start in time.
The tape machine is excellent for dropping bits of drum sequencers in and editing ,plus you have the sampler too. Don’t worry about extra complexity if its workin without.
Hey Spheric, sorry but after 10 second the tempo shifted and it’s not sync anymore, someone from Thomann told me that Midi is necessary and hopefully i found a SPL Crimson at a very very cheap price (from a friend), so i will have an audio interface but don’t really know what can i do with it
Hey Spheric, sorry but after 10 second the tempo shifted and it's not sync anymore, someone from Thomann told me that Midi is necessary and hopefully i found a SPL Crimson at a very very cheap price (from a friend), so i will have an audio interface but don't really know what can i do with it :(
clocks drift, midi sync fixes the delay before it’s too noticeable.
I was thinking you could just sample 4 or 8 bar stretches and use the tape to lift/drop sections to the bars of the Op1 (in beatmatch mode).
You should be able to get midi sync working with your interface and Logic.Two USBs ,one from OP and one from the Crimson,then a midi cable to the 707.
Perfect thanks guys will post a photo to show you how it looks like 