shin-ei octave - bc549 a,b or c -UPDATE: successfully built

[lowstar]

hi everybody,
etched a bunch of pcb´s during the last 2 days and now i´m ready to go again.
gonna start with alex´s shin-ei octave layout.
quick transistor question - should i use bc549 a.b or c ? i got all of them here.
for the germ diodes, does it matter if i use 1N34A or 1N60 ??

cheers,
lowstar

[Zero the hero]

I believe that gian in this design is not a issue, so you can use any BC549 you have. I used a bunch of BC547C and a BC560C.
Even the diodes should be equivalent.

[lowstar]

hey alex,
mille grazie for the fast answer.
had no time this morning cause i had to pick up an aguilar db750 with a matching db410 and bring it to the rehearsal room to a/b against my eden wt400/210xst rig at tonight´s rehearsal. and now you can call me spoiled 
but you can also call me godzilla cause i lugged the gear around alone   

and i just found out i´m short of one 6n8 and a couple 100n´s...think the shin-ei will have to wait till tomorow for it´s completion.

cheers,
lowstar

[lowstar]

hi everybody,
just fired it up 5 minutes ago and it worked right away.
clean octave down, not synthesized sounding like, let´s say, oc-2. the switch turns the direct signal on/off.
the tracking is ok on guitar, a little less on bass.
found transistors and germ diodes that were a 100% match (from the dmm readings, i mean  )
i think it won´t make it into a box because the oc-2 clone really tracks better (and sounds better for the classic bass octaver sounds)
but anyway, thanks for the layout and project, alex !

cheers,
lowstar

[Morocotopo]

Hi, are the circuits you´re talking about clean (no distortion) octave down generators? If so, where could I find them??? Sounds like something I would like to build...

[Zero the hero]

Congrats!
Thanks for this review, I always appreciate comments about the projects I post. I personally like this little octaver, it tracks way better than the BlueBox and it has a more natural sound.
Morocotopo, the Shin-Ei Octave layout has been posted in my site, while I don't know any Boss OC-2 layout.

[lowstar]

yeah, no oc-2 layout anywhere. i did my own veroboard layout (omitting the 2nd octave down part). it is pretty big, and gave me a lot of troubles for there was some noise bleeding into the powerrails. i finally solved it, but actually don´t know how cause i did many things at once (caps across the ic´s, shielded cable for some connexions, cutting unused portions of the strip that were carrying signal or power, etc).
but now that it´s working, it is fantastic. it tracks better than the original (don´t ask me why) and the sound is also more growly. maybe it is that i generally use higher quality components (a lot of film caps where mass produce has ceramics), i dunno...

cheers,
lowstar

[Zero the hero]

Although having bought (yes, BOUGHT!) the OC-2 schematic before was posted here, I decided not to clone it because the original is very common and the used one sare getting cheap, so I thought that the pain of drawing a layout was too much compared to the price of an original Boss pedal...
The BA634 scared me, too... Where did you find it? I always try to draw layout using the most common and available parts, and this flip-flop was the other reason to avoid this project!
Congrats for the veroboarded OC-2! Now I'm breadboarding a Space Drum using LM13600 instead of the rare CA3904, but I'm getting some troubles with the VCO.

[lowstar]

hi zero !

i quickly flipped through my pages, and if i´m not mistaken, this is where the 4027 comes to play.
funny that you mention the original...they are not that cheap, i´m still trying to hunt one down for a reasonable price (which would have to be roughly around € 30) out of sentimental reasons...to add to my ce-2b and bf-2b. one day i hope i will find the lm-2b, ge-7b and pq-3b too, to complete the little collection. but for live playing, i prefer my own clones cos they have true bypass, and the oc-1 (that´s what i called mine) just sounds plain better.

cheers,
lowstar