Suggestions for a vintage tremelo pedal.

[gez]

P.S.  Any problems with supply noise (for those using wall-warts), just wire up a large value cap from the 100k's wiper to ground.  To be on the safe side use 22u or bigger.

[B Tremblay]

I replaced the stock gain stage (didn't bother crowding the breadboard with the buffer) with the elegantly simple MOSFET arrangement described by Gez and it works beautifully!

Thank you, Gez!

[gez]

Nice one!  Elegant...yes, I like that!  

[B Tremblay]

OK, here's the "final version."



Thanks again!

[B Tremblay]

Here's a quick clip (mp3, 174k)

Depth at 3:00, Speed (100k reverse-log) at max., then 50%, then min.

The circuit uses the input stage from Gez and the changes I listed in an earlier post.

[gez]

Definitely has that vintage-amp vibe, cool stuff!

[Marcos - Munky]

Hey Brian, thanks for the soundclip. I never saw a EA soundclip, it sounds very cool.

[Neutral]

I really like the sound of that as well.
Just what I'm after, a replacment for my twin reverb one which looses to much volume when I kick it in.

Any chance of a fully modified Schematic with all these changes?
I'm not sure if this is a really big ask, It just seems to me that you guys sometimes bang these together for fun!

Thanks for all this discussion on the EA Trem, I'm learning quickly.

[B Tremblay]

[V!N]

Hey thanks guys for all the info.
The EA sounds pretty cool, with plenty of gain too!
Can anyone tell me if the depth control can compeatly flatten the wave to give a straight boost?

:lol:

That's how I use mine ! The LFO has very nice vintage vibe. I would try some mods if I were you, make it faster or slower and the pulsing led is just .. too neat !

It was my first project as well, but I made a point-to-point version on one of Steve's perfboards. I first put just one wire from the board to one of the pots wrong and got myself a very interesting fuzzbox.

The kick you get from making your very first very own pedal is just great. When you get it to work .. it's almost impossible to describe the kick

I suggest you keep it simple by ordering the PCB at General Guitar Gadgets (unless you want to learn how to make and etch boards right away as well) and go to //smallbearelec.com for your components. Steve is a great guy who surely will help you out.

[V!N]

I've decided that my virgin project will be a tremelo pedal, because they seem simple to build, and I want one!
I am after a few suggestions to point me towards the right schematic.
I want a basic classic sine wave based amp tremelo.
Knobs I want:
-Depth
-Rate
-Volume (I want PLENTY of volume to boost it louder than the bypassed signal, now that I think of it, if the Depth control was able to compleately flatten the wave, you could use this as a straight volume boost, now that would be cool!)

If there is a circuit that adds a sine to square wave shaper, like the marshal tremelo pedal, then that is a bonus, but not really desired, I want to keep this fairly simple.

I would really appreciate any suggestions and recomendations from you experienced folks!

Thanks.

[Neutral]

Thanks a million to B Tremblay for the schematic.
I'm going to get my bits A.S.A.P and get cracking.
I'm going to map it out on stripboard.

[V!N]

Great ! Be sure to keep us posted on what you're doing and why and how it sounds for you.

Also, if you find out what the mod was that I performed to make it an EA Fuzzbox, please let me know.

[B Tremblay]

A perfboard layout for the modifed EA Tremolo is now available.

[Neutral]

Awsome! Nice site, very pro.
Unfortunantly they only had stripboard at my local shop, but I should be able to map the parts out vertically on this stuff, without having to cut through the tracks too much, and still keep it small enough for the box.

As this is my first official pedal I'm permitted one daft question:

How do I measure the voltage at Q1 drain?

Thanks.

[B Tremblay]

How do I measure the voltage at Q1 drain?

Using a DMM set to measure DC volts, the positive test lead is placed at the drain of Q1 and the negative lead is in contact with circuit ground.  Adjust the 100k trimpot until the DMM reads 4.5 to 5 volts.  If it helps, my trimpot is set close to its midpoint.

Thanks for the compliment on the site, I'm glad you've found it useful.

[smoguzbenjamin]

Take a digital volt meter and measure the volts... That's how I'd do it :mrgreen:
Oh darn. Someone beat me to it.

[V!N]

A perfboard layout for the modifed EA Tremolo is now available.

You seem to like perfboard a lot, may we call you perferted ?

It looks great, I wish I had a guide-line like that when I began.

Just one little thing: the 22uF cap should have the shaded side on the left, rather than below.

[B Tremblay]

You seem to like perfboard a lot, may we call you perferted ?

It looks great, I wish I had a guide-line like that when I began.

Just one little thing: the 22uF cap should have the shaded side on the left, rather than below.

"Perferted" describes me perf-ectly.  Never etched a PCB.

Thanks for catching that error, a corrected version is now available.  Also, I replaced the single sound clip with three new ones.

[B Tremblay]

I've revised the perfboard layout (again).  The spacing for the 1uF and .47uF caps was a bit small.  To accomodate more realistic cap sizes, the layout now uses a trimmed medium size perfboard.

I built it with the small perf version, but it was pretty cramped and I had to relocate a few components.

http://runoffgroove.com/eatremolo.html