Easyvibe volume question

[BDuguay]

I recently built the easyvibe for a blues player friend of mine and we noticed a slight drop in volume when the effect was engaged. I've read a post here that talked about putting a volume pot in the circuit. Does anyone know more about this, or how to solve the slight volume drop?
Brian

[RDV]

I'm going to build one as soon as the parts get here, so I've been looking at the layout quite a bit. It looks like R16(100K to ground) may control output level. You could try a 100K pot there, or a smaller value resistor?

I could easily be wrong, so someone jump on in and let us know, cause I'd like to know as well.

RDV

[MarkB]

Mine has no noticeable drop in volume... there may be one, but it's so small it's insignificant.
I'll plug it in later and listen more carefully.
"-)

[Chris R]

I know the uni-vibe volume pot has to be on 9 not to have a drop in the signal.. at Volume 10 there is a slight boost & 1-8 its quieter.

I don't know if the EasyVibe functions the same or not.

Chris

[lightningfingers]

i have the parts but my LFO wont work :cry:

[Hungeryhippie]

I experienced this volume drop it wasnt huge but it was there. What helped me out was by using an output buffer (like the one found in the Clyde McCoy wha) and then u can adjust the o/p level with the 100K trimpot to match the bypassed level. It worked for me hope it helps.

[jrc4558]

Guys, do you know how to build a non-inverting amplifier using an op-amp? With the gain of 3? that's all you need instead of a first stage!!

[BDuguay]

Hey Constantin
I'll admit I don't know. Can you explain it to me please?
thanks,
Brian

[RDV]

Hey Constantin, I'll admit I don't know. Can you explain it to me please?

Check this thread which shows how to do a volume recovery stage on a Dist+, you can also do it on the easyvibe.
http://diystompboxes.com/sboxforum/viewtopic.php?t=19538&start=0&postdays=0&postorder=asc&highlight=vol+volume+recovery

RDV

[jrc4558]

OK, here what you do. Let's assume you're using a dual op-amp for your input stage on eazy vibe. We will use the 1234 side(left one if looking from the top) the pins are numbered 1(top) 4(bottom, connected to ground). there's a 47k between pins 1 and 2 and there's a 100k from pin 2 to bias rail. Replace the 47k with a 1K potentiometer(linear works better), and replace the 100k with a 1k resistor followed by a 10mF capacitor. Now you have a variable gain stage on the input with a gain of 2 and almost no frequency amplitude alterations. That's it.
Ask more if you need to.

[george]

one easy thing you can try first ...

is just increase the input cap from 1nF to 0.01 or even 0.1uF.

The standard cap cuts the bass a LOT, this might be causing the apparent volume drop.

I did this on mine, it now sounds a lot fuller, I also don't notice any volume drop when it's engaged ....

hth ...