madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: pryde on December 14, 2011, 12:08:21 AM

Title: Egodriver fizz
Post by: pryde on December 14, 2011, 12:08:21 AM
Hello,

I love my egodriver, it sounds very good overall. The only issue I notice is there is a fair amount of fizzy artifact only when the sustain is decaying. It does not seam to have a smooth decay at all. This happens with the normal and LED clipping options and on both LP/HP.

Is this normal with this circuit or is there anything I can do to improve this?

Thanks for any advice
Title: Re: Egodriver fizz
Post by: k.rock! on December 14, 2011, 02:42:36 PM
How are you powering it? Battery or power supply?

-Kaleb
Title: Re: Egodriver fizz
Post by: tenwatt on December 14, 2011, 02:50:17 PM
You know, I have the same trouble with the new board.  I just assumed that I had a bad connection somewhere but now that I hear someone else has the problem...

Mine only happens with the LED clipping though.  Like you said, at the end of the notes sustain it crackles and sounds fizzy.
Title: Re: Egodriver fizz
Post by: pryde on December 14, 2011, 03:40:36 PM
It does it with both battery and wall power.

Upon closer listening, it is more noticable with LED clipping but it does happen with normal as well. It is most noticable with higher gain on the pedal and the guitar volume rolled-back a bit.

Again, the pedal sounds great overall it just this one little issue I noticed. It could be bad solder/wiring somewhere on my part or maybe it is just the pedal circuit itself?

I don't notice any fizz/fart decay with my grapevine build or my Timmy pedal. However, there is a good amount I notice with my Rat clone so it could be just the nature of the higher gain pedals.
Title: Re: Egodriver fizz
Post by: jkokura on December 14, 2011, 04:14:45 PM
The IC you use will have a lot of influence on this sort of noise. The TL082 is likely the suspect cause in my opinion, and I ended up switching it out for an RC4558 in my build.

I recommend trying any number of higher quality IC's. If it disappears, great! If not, then you might have a power issue on your board.

Jacob
Title: Re: Egodriver fizz
Post by: k.rock! on December 14, 2011, 04:26:32 PM
I assume you guys did this but I'll ask for the heck of it, did you guys implement the fix on the Egodriver documentation? Apparently there was a problem with the latest boards with the LEDs being grounded...

-K
Title: Re: Egodriver fizz
Post by: tenwatt on December 14, 2011, 04:43:18 PM
Quote from: k.rock! on December 14, 2011, 04:26:32 PM
I assume you guys did this but I'll ask for the heck of it, did you guys implement the fix on the Egodriver documentation? Apparently there was a problem with the latest boards with the LEDs being grounded...

-K

Yup.
Title: Re: Egodriver fizz
Post by: pryde on December 14, 2011, 05:40:08 PM
Yes, did the LED grounding correctly.

The TL082 i used was from radio shack. Maybe I will try a RC4558 or another TL082 as my IC is socketed.

Are the radio shack IC's all poor quality? Where would I get higher quality IC's?
Title: Re: Egodriver fizz
Post by: jkokura on December 14, 2011, 06:02:19 PM
Probably the Radio Shack IC isn't really great, but it should work just like any other TL082. It's probably a clone or a work alike if it isn't actually a Texas Instruments IC.

It's not so much that the Radio Shack unit is terrible, but rather that the TL082 is an inferior IC compared to many others.

Jacob
Title: Re: Egodriver fizz
Post by: pryde on December 14, 2011, 07:13:04 PM
Looks like RS does not carry any of the other IC's recommended. I don't know if there is any similar one to the TL082 they sell that i could try?

http://www.radioshack.com/family/index.jsp?categoryId=2032279&pg=1

Title: Re: Egodriver fizz
Post by: jkokura on December 14, 2011, 07:20:17 PM
Where do you live? Most people here would send you a different IC for 2-3 bucks. Alternatively, you should take a look on ebay, or smallbear, or mammoth for various options. Perhaps some others here will chime in on what IC they like. As I mentioned, I liked the RC4558 but you could also try the JRC4558, TL072, NE5532, LM1458, TL2262, OP275, OPA2134, or any number of other dual op amps.

Jacob
Title: Re: Egodriver fizz
Post by: pryde on December 14, 2011, 07:48:47 PM
thanks Jokura.

I can certainly get some ICs next time I make an online order (smallbear or mammoth). I was just curious if my local RS had something else to try to see if the TL082 was the culprit.