Octave for bass.

[paulyy]

Looking for a good octave for bass for my friend. I dont play bass so not  sure what would be good. Any ideas would be great. Thanks.

[Earthscum]

octave down, or octave up? Octave down I found is a bit harder for bass than guitar... depending on what's cutting low signals in the rest of your chain, I was finding that anything below about third fret, E string, was getting flapped (about how it sounded... not really phasing) back and forth between the fundamental and the lower octave.

If ya want a clean octave up that's easy. I found Tim Escebedo's Octup! to work beautifully for bass, just the way it is presented. I  did notice a MUCH better sound when you take out the 10uF cap from the source of the fets. Much cleaner, a perfect octave up... not even noticeable until you start switching the effect in and out. After that you will need a small boost to get back up to unity, but I think it's worth it. I may box one up for myself just for those times when I want the higher notes, but it needs to be thick enough to sit right in the song. After that box, you can run any effect you want, and the octave up works just like a normal signal, only... up. It was a fun circuit to play with.

Also for up octave, Bobtavia was kinda neat... gritty. It uses LM386 and CellShack transformer. The build I did seemed to get more synthy the closer to the bottom end I got.
Tim's Pushme Pullyou was kinda good... seems to have some good tweaking points for really shaping the sound, and it's simple.
And the Octup Blender looks promising, but I haven't tried it yet.

[DerHoggz]

The OC-2 is one of the more well known octaves for bass.  It is basically a lowpassed square wave.  There are all kinds of square wave octaves around.  Generally speaking though, tracking won't be good on the low notes.

[paulyy]

Thanks for the replies. I guess an octave up would be good for bass. Iv been looking on Tonpade, GGG and Madbean's layouts for ideas but I guess I need to do more reseach. My friend isnt picky. He just wants somthing that sounds good.

[Top Top]

I have gotten fine tracking on squarewave CMOS based octave downs for bass. The problem is more that the frequency becomes too low to actually be useful.

[Earthscum]

Aye, that's what I was noticing. I'm working on a synth pedal for my woman and pretty much decided that I'm SOL on that, unless I keep the pulse short enough, then it doesn't get wiped out farther down the chain. The only bad thing is that the lower notes start to shift in their sound. When I start to shape them towards saw (I'm guessing by sound, since I don't have an o-scope), they seem to start to play a bit nicer with the filtering down the chain. Tracking on that particular circuit is not a problem... I'm buffering the DM7474 (pos edge flip flop) output with a leftover schmitt, which let me add some shape to that square.