Tremulus Lune and Calgate discovery

Started by KMS, June 07, 2006, 01:56:39 AM

Previous topic - Next topic

KMS

I built both the Lune and the Calgate from the tonepad layout in 2004 and both worked great using a 9v battery for each. I had both installed in Phenolic boxes.

This issue seems to be about a discovery concerning the Power Supply. :icon_rolleyes:

In Dec 2006 I made a multi stage DC Power Supply with an adjustable bipolar output, a regulated 3v output, a regulated 9v output, and a regulated 12v output.

I then broke down all my stompboxes and installed them into one floor counsel stompbox (made of steel) with the 9v regulated output powering all the lights, my switching matrix which includes two 4PDT 5V relays, and for the sake of easy wiring my Orange Squeezer (the 9v was was easy to hook up to the OS).

I made a 10 channel stereo mixer and a 6 channel GEO ABY both operating on the adjustable bipolar, set at 9.1v and installed inside the big stompbox. The Lune, the Calgate, and my Boss OD also inside the big stompbox are wired to the pos/0v of the 9v bipolar. (my crybaby remains separate from the counsel but is also hooked up to the pos/0v of the 9v bipolar and is routed through one of the channels from the ABY and one channel of the mixer.

The input signal runs through the noise gate first and then through the OS and then is separated through the 6x ABY where I am using one channel each for clean, Boss OD, the Lune, and the Crybaby.

The ground from the 9v and also the 0v from the bipolar are isolated except once inside the big stompbox they are hooked together near the center of the box (and grounded to the box) where all the ground wires have a common terminal point.  This was needed to stop the hum.

That is the story on how the PS is hooked up (the 3v and 12v sections of the PS are not in service).

No problems with sound quality except;

First thing I noticed was a "woosh" sound in sync with the rate on the Lune. It was not that loud but just loud enough to bother me when I'm not playing. The "woosh" sound persisted even with the Lune in true bypass.

Also, the Calgate now needed the sensitivity on max to work and the smooth clamping that I worked so hard to achieve (using a matched pair of FETs) was not so smooth anymore.

I had read on several posts that a 100uf cap between +V and ground would solve the problems of a "ticking" sound associated with the Tremulus Lune but I had ignored them because I did not have a ticking sound.

So I finally decided to try a cap between +V and ground on the Lune to see what would happen and all I had laying around was a 3300uf.....which is now permently part of my Lune.

The woosh sound is gone and all of my FX sound much better.  The Calgate will operate on the lowest sensitivity setting (which it never did before) and is as smooth as any noise gate I have ever heard.

I know this is a power issue....but what is puzzling me is why the Calgate operates better than it did with a battery?

Any ideas? :)



DIY with-a-little-help from my freinds
DIY with-a-little-help from my freinds

KMS

One other comment that some DIYers might be interested in........

I have the Lune and the Crybaby on separate ABY & separate mixer channels where the Crybaby signal is output to a different amp than the Lune.  With the Lune set on a moderate slow speed, full depth, all other controls off on the Lune and operating the Crybaby in sync with the Lune I get an amazing sound.  It literally sounds like a phaser/rotary sound.  It is too cool to be true...but it is a fact.  What I like about it is the random changes due to imperfections in my Crybaby sync and the different levels of "wha" that I get which you don't get from an auto phaser.

I tried this phaser/rotary method coming out of my Orange Squeezer prior to the ABY on the second guitar part of Skynyrd's Simpleman.....you know...the Bush beer jingle (the intro and main rhythm 1 of the song) and it sounds just like the original studio version....as long as I don't push the crybaby too far with the heel and be sure to push the toe all the way on the high notes (of course guitar 1 is clean and the whole Simpleman feeling is not possible without guitar 1.)

My band mates were amazed......it is a totally awesome sound.

Multiple parallel channels with multiple FX matrixing is well worth the time and work to build....well worth it indeed.
DIY with-a-little-help from my freinds
DIY with-a-little-help from my freinds

KMS

I know I said "discovery" and I guess what I mean is...what the heck is going on here?

Why does the noise gate work better?

I'm not convinced that the new big 3300uf cap I installed on the Lune should make any difference in the performance of the noise gate.

Is it possible that my noise gate is about to shoot craps due to some other issue and the improved performance is just coincidentally happening at the same time I installed the cap on the Lune?

Trying to understand this?????

Maybe RG has an idea?
DIY with-a-little-help from my freinds
DIY with-a-little-help from my freinds

Mark Hammer

Here's a theory.

The "smoothing" cap (that is 3300uf in your case - Holy frijoles, Batman, that's a biggun! :icon_eek: ) performs two functions.  First, it stabilizes the power so that what has been rectified in the wallwart behaves much more like steady battery power.  But, it also performs the role of providing a "current reservoir".  Much noise in pedals (especially ticking) occurs when different semiconductors have to fight for their fair share of the same current source.  Devices that produce, for one reason or another, a sudden sharp swing in current draw, cna introduce mini-spikes on the power lines that are picked up by other devices. 

In "the old days", if your mom was using the sewing machine in one part of the house, or if the fridge compressor suddenly tuned on, the result would be noise on the TV image or from the radio or stereo, largely because none of these things had enough power regulation to prevent their specific needs from affecting all the other things sharing the same power lines to the house.  The very same thing goes on within pedals, except that instead of multiple appliances, it might be separate op-amps, and instead of wall-socket power, its a 9v battery.

My sense is that - even though its several times larger than was really needed to do the job - your smoothing cap provided enough of a current reservoir with stored charge, that everyone had plenty of juice to go around.

KMS

I agree that the cap is much bigger than I needed......but it is what I had on the bench.

It makes since that the big cap works like a reservoir (surplus) supply for the other pedals...I understand that and it helps to hear it from others......I'm still learning.

The noise gate (it has been a while since I looked the circuit over) I think it has a zener diode that regulates the power (voltage).

I forgot that I now have an analog delay in front of the noise gate (which I have never done that before)  sorry but it so easy to change the scenario and not remember all the changes. This could definitely play a role and I had not considered it. One thing is for sure....the noise gate is working great, and so is the Lune.

I'm getting ready to add some more circuits to this living-breathing-stompbox.

One thing I need for sure is something that will give me a really high note.....octave up....two octaves up and right at the end of my real signal. Many of Skynyrd's leads (Rossington) end with a note held for a couple of seconds and then the note morphs to an octave or two above the real note.  You can tell it is not fret move, rather it is electronic somehow. I don't know how they did that...do you?

Thanks Mark.
DIY with-a-little-help from my freinds
DIY with-a-little-help from my freinds