EA Trem - Simple Speed Mod

[alteredsounds]

I needed the extra top-end speed so pulled the 3 uf's and put in 3 680n's. Top speed is super fast now but I found that the slow end was now too fast, to combat this, I simply soldered in a 2.2uf in parallel with one of the 680n's and hooked it up to a switch.  I can now switch to a slow speed that is so slow its not barely audible or flick the switch and get the super fast top speed.  I will replace this switch with a stomp so I can instantly swap.

One question is that the effect never seems 100% 'wet'.  I have used a 1meg depth pot but would like to get a 100% 'wet' sound, any ideas?

[audioguy]

can you describe how you wired the switch/cap???

[alteredsounds]

Sure, give me a bit and I'll draw it up

[audioguy]

cool!

[RDV]

One question is that the effect never seems 100% 'wet'.  I have used a 1meg depth pot but would like to get a 100% 'wet' sound, any ideas?

If you have a resistor to ground(68k on the ROG schem) from the depth pot, short it and see what happens.

EDIT: I just realized that if you're using a 1meg pot then you've built the GGG version and you have no resistor there. Sorry.

RDV

[alteredsounds]

RDV cheers for your reply.  I'm doing the ROG from Torchy's layout so your prob right with the resistor you mentioned.  Gonna try it right now!  Thanks again

[alteredsounds]

Not on my pc so have VERY basic gfx prog here, hope it makes sense!

[squigglefunk]

wow! thanks for the cool idea, I hope you don't mind if i try it on my ea trem! I have a giant old volume pedal I'm building the trem into so I can control the speed too, this mod might really cool to add to it as well.

peace!

[Transmogrifox]

The EA trem has illicited a good number of threads regarding the "not deep enough depth, not wet enough".  I have recommended using a constant current source to bias the amplifier transistor to make it deeper.  I haven't breadboarded it this way yet to see how much it helps, but one of these days I'll verify.

Do a search on the EA trem and you'll probably turn up one of my posts that links to the schematic illustrating the constant current source.

[Processaurus]

The EA trem has illicited a good number of threads regarding the "not deep enough depth, not wet enough".  I have recommended using a constant current source to bias the amplifier transistor to make it deeper.  I haven't breadboarded it this way yet to see how much it helps, but one of these days I'll verify.

Do a search on the EA trem and you'll probably turn up one of my posts that links to the schematic illustrating the constant current source.

I've got to try that sometime soon, if it works it would make the EA trem just about perfect.

[audioguy]

Is that switch an ON-ON 3 pole switch?

[alteredsounds]

'Is that switch an ON-ON 3 pole switch?'

yep it is, I omitted the rate double-switch as it isnt needed with it wired this way.  There is alot of mods for this trem but I found this the quickest way to do exactly what I wanted and now have my perfect trem pedal. Also, when using a 1 meg Depth pedal, replacing the 68k with a 100k seems to be the job.  Some1 suggested this ages ago, sorry I forgot who (Dragonfly?).

[Ge_Whiz]

The depth of the EA tremelo is critically dependent on the properties of the FET used. As you may be aware, the tolerances on JFET performance criteria tend to be huge, so this property is, unfortunately, bound to differ from one build to another. I built mine with a 2N5457 and swapped them around to get the depth I wanted (which is pretty deep).