Hi people!

Any suggestions for that "Byrds" sound?
JangleBox schematic anyone?


Thanks
Manolis
About 8 Miles High..

R. McGuinn has talked about how they got that sound. As I recall, bridge pickup, straight into the board, compression added at the board. If you search the Web you'll probably find the interview. He had also been a banjo player, so some of his guitar sound comes from banjo technique. There is also a tape or video where he explains it all - it might be on the Homespun Tape site.

Not sure where I got this (RG?), but it is the schematic for what I gather is a Rick with an onboard (fixed) compressor.  Given the Byrds reference, my guess is that, even IF this is from an official Rickenbacker 12-string, the classic passive Byrds sound (which may well be a product of post-production studio limiting that this circuit seeks to emulate) predates it by at least 4 or 5 years.  Whatever the case, I'm pretty confident that Rickenbacker - a company not known for messing with success - did not strive to diverge much from the sonic formula that made their 12-string a cash cow that Roger McGuinn and later Tom Petty would milk for them.


Those who have followed the Dynacomp/Ross threads relentlessly will immediately notice the strong family resemblance between this circuit and those other two beasts.  It isn't indicated, but I would be very strongly surprised if the unnamed IC wasn't a CA3080.  It's drawn a little differently, but Q2 is obviously the phase splitter that feeds the rectifier formed by Q3 and Q4, and also forms the output path.

You will  note that there is no variable control over the amount of compression here, merely a single 33k fixed resistor replacing the 27k resistor and 500k pot in the DynaRoss.  You will also note that while the Ross and Dynacomp have values of 10uf and 150k for the averaging capacitor and the chargeup (recovery) resistor just before Q5, the Rick circuit uses 2.2uf and 1m.  So, the general picture here is: a) strong compression (because of the 33k resistor), fast attack and longish recovery (because of the 2.2uf/1m combo).  The 82k/10k combination on the output simply provides approximately equal level compared to the fully passive bypassed-compressor sound.  What the rest of the circuit does to the tone is beyond my perimeter of expertise.

Check the "New at GEO" list for 5/22/02 and you find:




Which, oddly enough, is that same circuit. 

It's a mutated Dynacomp, OK. I had an old Rick 360 and wanted to experiment. The pickguard is opaque white lucite, like the ones on Ricks. Worked fine.

I had a devil of a time getting the switch pins extended and put in place though.

I can imagine that getting the solder pads and rotary switch pins lined may have compromised your hairline and lifespan somewhat.   

But you've muddied some waters for me.  Is the posted circuit an actual Rickenbacker circuit and you simply attempted to clone it, or is the circuit your "version" of it?

I suppose the other question to ask is whether - given the importance of time constants in the "feel" of side-chain controlled circuits - the change from 10uf/150k to 2.2uf/1m is worth pursuing for any reason (more "jangle"?) or whether it is simply what they used and not discernibly different from stock Dyna/Ross values.