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DIY Stompboxes => Building your own stompbox => Topic started by: jkokura on April 01, 2010, 02:01:23 AM

Title: GGG Phase 45 question
Post by: jkokura on April 01, 2010, 02:01:23 AM
GGG Phase 45 details can be found here: http://www.generalguitargadgets.com/content/view/156/26/ (http://www.generalguitargadgets.com/content/view/156/26/)

My question is about the 1.5M resistor of the input - I don't have a 1.5M Resistor available. GGG's project file says this is for bypass pop prevention. Is there another value I can use? Will a 100k resistor, or a 470K or some other value work just fine? I have limited spares at any large size, and don't want to place an order for one 1.5M resistor...

Jacob
Title: Re: GGG Phase 45 question
Post by: served on April 01, 2010, 02:53:12 AM
You shouldnot change the value, too much signal goes lost. This resistor drives the input signal straight to ground. Most of the pedals have 1M there, it can be bigger i think. But 470k for you is too low.
Title: Re: GGG Phase 45 question
Post by: Mark Hammer on April 01, 2010, 08:53:44 AM
Yep.  Almost anything 1M or up is fine, although if the very best you could do with what's in your parts bin is 680k, I don't think you'd be missing wads of signal as a result.

In some respects, you don't want the resistor value to be too high.  The intent of the resistor is to let the charge stored in the input cap drainoff.  And if the resistance becomes too high....wll then it sorta starts to resemble open circuit, doesn't it?
Title: Re: GGG Phase 45 question
Post by: jkokura on April 01, 2010, 10:56:34 AM
So the GGG documentation says this is optional - can I just leave it out? Obviously if I'm getting pop when I switch the circuit on and off I should put it in, but does it even need to be included? I think the closest I have is 1M, but I'm not sure if I have an extra or if the 1M's I have are designated for another upcoming project...

Jacob
Title: Re: GGG Phase 45 question
Post by: therecordingart on April 01, 2010, 11:50:40 AM
Take one of your 1M and put it in series with your 470k.