Synth pedal discussion

Spectrum · #1 02-07-2013, 12:56 AM

This is a question for you synth heads out there, Flux Jetson et al.

I have a Behringer BSY600 sunth pedal, which is the cheapo clone of the Boss SYB-5, and I'm trying to get a better grasp of how these things work.

When I do a google search on "how synthsizers work", I get led to pages that explain that an analogue synth basically consists of a series of stages, the first being an oscillator which generates a sine, square, triangle, or sawtooth wave. The next stage is the filters, and the final stage is the amplifier. There can also be other modules like LFOs and so forth. The BSY600 has an LFO.

So I guess my first question is: how is that initial waveform generated in one of these pedals? It gets the raw audio signal from the bass pickups, but where does it go from there? Is that raw instrument output the initial waveform, or is the circuit "reading" the frequency and producing a sine (or whatever) waveform of its own at the same note?

I also have the Digitech Bass Synth Wah, which, according to what I've read, is not a real synth pedal but just a really good filter, using the raw instrument signal as the wavefrom source. Am I wrong?

I have more questions, but I'll start with those ones.

Skrogh · #2 02-07-2013, 01:15 AM

The bsy-600 tracks your pitch and envelope. The pitch is used to pitch a saw-wave oscillator at the same pitch; this is fed into a look up table to generate whatever other waveforms it has (the pulse is just the saw compared with a value from an LFO). The envelope is used to generate a trigger and gate signal for an envelope generator controlling the filter. I think there are a couple of the modes with "direct synthesis" too, where the input is distorted and fed through the filter instead of the oscillators.

Spectrum · #3 02-07-2013, 05:18 PM

Okay, I see, so it depends on which mode the pedal is in, then, that makes sense. But when set to the square or saw wave modes it is reading the signal from the bass and then making its own source waveform.

bongomania · #4 02-07-2013, 11:16 PM

It generates its own internal waveforms, which are totally unrelated and unconnected to the sound of your bass. The bass only provides some triggering information: when the note starts and stops, and what pitch is being played. The glitches, delays, and stuttering of a synth pedal are its clumsy attempts to correctly identify the start/stop and pitch of each note, and then produce the appropriate triggered response.

Spectrum · #5 02-08-2013, 03:42 PM

Quote:

Originally Posted by bongomania

It generates its own internal waveforms, which are totally unrelated and unconnected to the sound of your bass. The bass only provides some triggering information: when the note starts and stops, and what pitch is being played. The glitches, delays, and stuttering of a synth pedal are its clumsy attempts to correctly identify the start/stop and pitch of each note, and then produce the appropriate triggered response.

Ah, that makes sense. And it also makes it clear why you have to learn how to "play the pedal" to get it to track well, since it has to deal with my sloppy human bass-playing.

I've notice that if I make the effort to play only one note at a time, very clear and precise, it works much better. If more than one note is ringing it gets confused.

Next question: I've seen the Boss SYB-5 looped around to play by itself. Can the BSY600 do this, too?

Meddle · #6 02-08-2013, 04:03 PM

Synth pedals seem to have some recurring themes...

1) They either have an envelope that is triggered by the 'attack' of the incoming bass signal (so triggering with each note you play like an old Mutron III).

2) Or... they have an envelope that is driven by an LFO. This is arguably more 'synthy' because the rise and fall of the envelope is independant of the incoming signal.

3) They filter your bass signal with fuzz style effects (Ibanez's Tonelok bass synth does this) so the tracking is excellent because it isn't actually tracking a thing.

4) They generate their own sine or saw wave forms internally (sort of like the Boss OC-3 or EHX POG). Tracking is inherently unstable (better with flatwound strings that don't fire off a bunch of random harmonics) but with clean playing it can be good!

bigchiefbc · #7 02-09-2013, 06:48 PM

Quote:

Originally Posted by Spectrum

Ah, that makes sense. And it also makes it clear why you have to learn how to "play the pedal" to get it to track well, since it has to deal with my sloppy human bass-playing.

I've notice that if I make the effort to play only one note at a time, very clear and precise, it works much better. If more than one note is ringing it gets confused.

Next question: I've seen the Boss SYB-5 looped around to play by itself. Can the BSY600 do this, too?

1.) yes, you need to play cleanly with the BSY600 (as well as the SYB5, the Deep Impact, the Octavius Squeezer, and also every other synth or analog octave pedal). I've found that if I put my bass in passive mode and turn down all the EQ knobs, it tracks great and almost never glitches on me. Even with roundwound strings and even when playing with a pick. Definitely don't try to play chords and don't let extra strings ring out.

2.) yes, you should be able to do that same trick with the BSY600. Turn the direct knob all the way up, connect the direct out jack to the input, and then you should get a synth tone coming out of the effect out jack.

gastric · #8 02-10-2013, 11:03 AM

Welcome to the fun of triggering monosynth effects!

I tried hard to get myself into an elecrosynth band where I'd play pure bass synth via effects. Never could get a band to stick together. And after 12+ months I got in the nasty habbit of playing everything mono, cleanly, and fairly staccato for tracking. It's a hard habit to break now and usually sounds mechanical when playing rock-n-roll that way.

Spectrum · #9 02-10-2013, 11:43 AM

I mostly use my synth pedals for special effects during parts of songs, they don't stay on very long as I need to actually play bass, too. But we're experimenting with writing some trippier stuff and I'm trying to really explore these devices to get the most out of them. Playing with synth and a delay pedal is great fun, for example.

The self-triggering synth pedal trick is something I might be able to use if I switch in on a seperate line or something. The BSY600 is a really cool synth, despite the awful plastic case Behringer put it in. I want to get a SYB-5 one of these days and compare the two.

anton72 · #10 02-10-2013, 11:48 AM

Tried every bass synth exept Octavius and stopped at Akai Deep Impact. Yes it has some tracking issues as well as the others (you just should play accurate) but it's miles better than others in terms of the tone.

Spectrum · #11 03-22-2013, 10:01 PM

Quote:

Originally Posted by bigchiefbc

2.) yes, you should be able to do that same trick with the BSY600. Turn the direct knob all the way up, connect the direct out jack to the input, and then you should get a synth tone coming out of the effect out jack.

Actually, you are almost right; I got it to work but I connected the direct out to the amplifier and the effect out to the input.

Then I decided to put a delay pedal in the feedback loop and got some cool stuff:

http://www.youtube.com/watch?v=Dm1SI...ature=youtu.be

I don't see much practical use for this arrangement, not for a live show anyway, but it sure is fun to play with.

oldprussians · #12 04-03-2013, 05:50 AM

I think there 2 things to think about when considering Synth Pedals, apart from the "either you like it or not", which is the fundamental question.

1 The setting you are playing it in:

If you are playing with a keyboard player, then you are flogging a dead 'orse! You will never sound as good as an actual keyboard player.
If on the other side you playing in keyboard less band such as Oysterhead, one can see the benefits.

2 The actual pedal and how it works:

Other have already described the two types. But I will ad this:
All trigger based synth application will inevitably have tracking issues. Analogue Octave pedals just about manage, but you will have issues if you play fast.

The there is the issue of what a synth is!

When they were looking at making synths they were looking at what envelope filters, and distortion pedals were doing to waves that were coming from guitars, and then "synthesizing" them. So instead of triggering a sound, that is a synthetic "copy" of guitar/bass effected sound, wouldn't it be better to cut to the chase and just using that effect sound? For that reason I am leaning towards whet the Ibanez tonelok pedal does rather that the, trigger sound. the only issue with the Ibanez is the naff tone suck on by pass.....

That just my 2 cents worth!

bigchiefbc · #13 04-03-2013, 02:00 PM

Quote:

Originally Posted by oldprussians

The there is the issue of what a synth is!

When they were looking at making synths they were looking at what envelope filters, and distortion pedals were doing to waves that were coming from guitars, and then "synthesizing" them. So instead of triggering a sound, that is a synthetic "copy" of guitar/bass effected sound, wouldn't it be better to cut to the chase and just using that effect sound? For that reason I am leaning towards whet the Ibanez tonelok pedal does rather that the, trigger sound. the only issue with the Ibanez is the naff tone suck on by pass.....

That just my 2 cents worth!

The first synthesizers were around long before distortion pedals and envelope filters. And they weren't meant to emulate guitars at all.

oldprussians · #14 04-03-2013, 02:09 PM

Quote:

Originally Posted by bigchiefbc

The first synthesizers were around long before distortion pedals and envelope filters. And they weren't meant to emulate guitars at all.

I didn't mean that!

guitar -> sound ->Effect to effect the wave..

sound from synth shaped at source.

Spectrum · #15 04-03-2013, 08:47 PM

I play in a hard rock trio, plain old guitar, bass, and drums. I use the synth effects for special effects during things like song intros and breakdowns, etc., where the music can spare the absence of actuall bass for a few bars.

But in my day job I'm an engineer and I have always been a tech geek and grew up listening to Tom Saywer, so effects and synthesizers call out to my nerd side and I'm trying to learn more about them. Up until recently I didn't use effects very much at all, but pedals are like coat hangers; you turn your back for a minute and they've multiplied. My band does originals so I have the freedom to experiment with anything I want, and I have always loved that synth sound, and I love the idea of doing it with my favorite instrument (my bass) instead of having to resort to using a keyboard or a laptop.