rotary speaker simulator

[Artcool]

Hi ,

i'm looking for a rotary speaker simulator schematic, as a matter of fact i'm building  a small version of a real rotary speaker (using parts of one of two big leslies i own ) in which i'll be using the upper rotor and two static speakers for the bass (two 6" speakers), my goal is to have the simulator acting only in the bass part (below 800 Hz) - I already have a 2 way 800 Hz passive crossover, so i think i will need a schematic with a circuit able to deal with an amplified input, is this possible? This way i could use only one amplifier->800 Hz passive crossover-> Treble to horn driver / Bass to simulator and bass speakers...

thanks!

[Mark Hammer]

Don't get me started.

There is a LOT of prior discourse on this topic on the forum, do some searching.  It is not a particularly easy thing to simulate thoroughly, though a variety of aspects of rotary speakers have been effectively accomplished.  But like I say, dig a bit and you'll find plenty here.

[StephenGiles]

There is always this!!


http://r1rk9np7bpcsfoeekl0khkd2juj27q3o-a-fc-opensocial.googleusercontent.com/gadgets/ifr?url=http%3A%2F%2Fwww.google.com%2Ffriendconnect%2Fgadgets%2Fmembers.xml&container=peoplesense&parent=http%3A%2F%2Fguitarz.blogspot.com%2F&mid=0&view=profile&libs=google.blog&d=0.549.6&lang=en&country=GB&communityId=13338852349297505845&caller=http%3A%2F%2Fguitarz.blogspot.com%2F2009%2F05%2Fandy-demonstrates-his-home-made-rotary.html

[Nasse]

There was old japanese unit with three stationary speakers, was it roland or yomaha... wonder how it was done, or was it good

[Mark Hammer]

You are thinking of the Roland Revo.

I think it was a motorless system that used an array of VCAs and power amps, along with a chorus circuit.  I remember hearing one in 1981 or so, and it didn't sound too bad.

[Nasse]

Yeah that was it, Roland, thanks, they did have 6 speakers model too. There was a debate on other place cant remember that such multi speaker system can not do doppler effect but I believe it can.

My dad used to ride one of this kind of gadget http://www.youtube.com/watch?v=aYrqVbsX85c and we used to superglue rubber rope, works great...

[Artcool]

thanks to all ..

yes, it seems something quite dificult, so i'm thinking in buying one Behringer RM-600 (its cheap) and unmount it for messing with it and try to do the bass simulator this way.

Of course i will need one active crossover in this scenario and two amps...let's see... other problem will be the speed change , in the Behringer one must press the pedal for 2 or more seconds to switch... i bet the guy who designed this is not a organ player

[Mark Hammer]

The Behringer RM-600 is a clone of the Line 6 Roto Machine.  I have one of the latter, and it's a very nice emulation of a rotating speaker....something I also have.

Apart from the plastic box (which doesn't bother me very much at all), the principle shortcoming of this pedal is the switching.  The original Line 6 pedal has a soft and hard-touch switch inside for bypassing and ramping under the same foot treadle.  Press hard to bypass, and tap gently to switch from fast to slow speed and vice versa.  There is a clear tactile difference between the two switches.  The Behringer let you bypass with a quick tap, but requires you to hold the switch down for 2 seconds to switch speeds.  Two seconds is not what I would call "on the fly", and is, for me anyway, a deal-breaker.

The caveat is that pretty much ANY rotary speaker simulator will sound very uninspiring, and not all THAT much better than a chorus or flanger pedal, unless you run it in stereo.  Others here can attest to that.

[Artcool]

Thanks Mark!!

yes, may be i decide to do some simple chorus (just for the bass frequencies) and solve the issue this way, two fixed resistors for the slow and fast speed and a relay to switch from the real upper motor switch...the 2 second switch in the behringer is not good indeed...

[Mark Hammer]

Well if you're going to go mono, a chorus, flanger or phaser with the right sonic properties can take you part of the way there.  Do examine the ramp up/down properties of the LERA adaptor over at geofex:  http://www.geofex.com/article_folders/lera/lera.htm

Lest I scare off too many, the actual rotary emulation on the Behringer/Line 6 is good, and when done in stereo is VERY persuasive.  If you're not the sort that goes back and forth between speeds, the 2 sec thing is not that big an issue.

[Artcool]

fantastic... this is something (the up/down ramp) i was wondering how to do ...you just gave me the answer ! yes, i play Hammond/leslie and quick switching is something i use often .. This project's goal is to have an alternate rig (Korg CX-3 vintage plus a small leslie speaker ) for smaller gigs thanks for your help on this!!