The Old Days
In the good old days everyone had a mixing console. People actually needed them. A sequencer could be locked up with a tape machine so a person could do all of their work on a MIDI sequencer, send that MIDI data out to a hardware synthesizer (or sampler) and then run that audio back to the mixing console. It was a fairly simple process. When the musician was ready to commit to their composition, they simply armed the proper tracks, hit play, and recorded the audio output of their synths to the tape for eventual mixing.
The Current Soft Synth World
These days there is a greatly diminished need for a mixing console in the typical home recording setup. The software synth world is all the rage and for good reason. You can do incredible things within the computer and the synths sound great in my opinion. These days the MIDI sequencer, synths, samples, and mixer are all within the computer and I can’t think of any good reason for a person starting from scratch to head down the old hardware synth path. The software based system works extremely well. Just add a MIDI controller (keyboard) to a laptop and you can begin creating masterpieces on the beach or playing live shows.
Combining Hardware and Software Synths
The situation becomes a bit more complex when a person wants to use their hardware synths with their recording software or computer based MIDI sequencer. The process is basically the same, at first. We enter MIDI data onto a MIDI track by playing a keyboard or entering dots with a mouse. That part is the same. When we hit play, that MIDI data is sent from the computer to the output of the MIDI port. That part is the same. When this MIDI data enters the hardware synth, a sound is triggered. This is also the same. What differs is what happens with the audio output of that hardware synth? If we were to route that MIDI data to a software synth, the output would automatically be routed to a channel in the software mixer. (Some recording software would require Rewire for this). However, there is no channel automatically created for the output of the hardware synth. The audio output really has nowhere to go. Not yet anyway.
It needs to be clear that we are still in the composing stages. The second we are ready to commit the output of the hardware synth to the wav file, we can simply record it into our recording software the same way we record a vocal or whatever to an audio track. However, we aren’t ready to commit because we are still building up our tune.
External mixer – I don’t recommend an external mixer often these days. Why You Don’t NEED A Mixer For Home Recording Current audio interfaces and modern ways of working with recording software have pretty much eliminated the need for external mixers. Working with hardware synths is one exception. We could build up our tracks in our recording software by running all audio already in our recording software through the stereo outputs and into our mixer and combine that signal with the outputs of our hardware synth in the mixer, send that the studio monitors, and be off to the races. When we are ready to commit, we simply route the outputs of the hardware synth to our audio interface and hit the record button.
Standard audio inputs – Your recording software allows you to monitor the signal through it. For example, when I record vocals, the vocal flows through the mic > preamp > audio interface and into a channel in my recording software when I add compression and maybe reverb. Then the signal is sent out of the audio interface and into both my studio monitors and the headphones of the singer so they can hear what they are actually singing. We could use a similar setup by arming a track and running the output of the hardware synth into the input of the audio interface. This would technically work, but it has some drawbacks.
A big problems is it uses up two channels of your audio interface. If you only have a 2 channel audio interface, you won’t be able to record anything with a microphone without first committing the MIDI stuff to wav. This is no good. Even if you did have extra channels, the fact that the audio track is always armed would mean you would constantly be recording to that synth track from the output of your external synth even though you only really want to be recording vocals. This is a very poor way of dealing with our hardware synth. Let’s dig deeper.
External Bus – I can’t speak for all recording software, but I was able to setup a system to allow the use of external synths in about 2 minutes (I had never done this before) in Cubase SX3. Cubase allows the creation of an external bus. This external bus means that the signal from a given set of inputs in the audio interface are permanently routed into the Cubase mixer just like we were using an analog mixer. I can apply effects real time, adjust levels, and do everything like you would expect with an analog mixer. The only real difference is that when we render down the mix, the mix must be done real time so that Cubase can record the incoming audio from the external synth and combine that along with the other tracks.
When I was sure I was finished composing, I’m sure I would go ahead and record each separate sound from the external synth to a separate track in the recording software simply because I may want to apply different effects and automation to different elements from the external synth.
I’m sure that Cubase isn’t the only recording software out there to have this sort of functionality. However, few recording software companies go out of their way to make a big deal about this feature. It’s becoming increasingly clear that more people are still using hardware synths than I had originally thought. Personally, I’m very pleased with the quality, ease of use, etc of the soft synths and I wouldn’t hesitate to use them in a live situation with a laptop (and I’m not exactly cutting edge on this).
It is possible to merge external hardware synths with soft synths within recording software if your audio interface is has enough inputs and you have a bit of creativity and willingness to crack open the manual. If your recording software doesn’t have the ability to route external audio into a channel/bus constantly you may have a problem.
Either way, I’m of the opinion that soft synths are the way to go. If you are about to invest big bucks in a modern hardware synth, take a look at the soft synths beforehand. I think you’ll be impressed. If you are vintage synth junkie, there is no hope for you (just like there is no hope for me and my vintage guitar amps). Ha ha