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Projects => Tech Help - Projects Page => Topic started by: gtangas on March 30, 2013, 04:13:56 PM

Title: Uproar... Noise on high freq
Post by: gtangas on March 30, 2013, 04:13:56 PM
Hi guys

I was playing yesterday with my uproar and something strange happen

With the mid boost engage it starts, sometimes, to break,noise, the distortion...

I used the values suggest by Brian.

It only happens with the switch on and on full gain

Any tips?
Title: Re: Uproar... Mid boost noise
Post by: gtangas on March 30, 2013, 05:39:51 PM
Any one?
Title: Re: Uproar... Mid boost noise
Post by: gtangas on March 31, 2013, 07:53:03 PM
...
Title: Re: Uproar... Mid boost noise
Post by: gtangas on April 01, 2013, 08:28:53 PM
Come on guys....
Title: Re: Uproar... Mid boost noise
Post by: stecykmi on April 01, 2013, 08:38:00 PM
is it the presence mod or the super-duper mid range booster mod?
Title: Re: Uproar... Mid boost noise
Post by: gtangas on April 01, 2013, 10:55:23 PM
Is the super-duper mid range booster mod

I made the presence mod but didn't make much difference...

When I flip the switch position I hear a squil noise and with the mod on I hear sometimes the same noise...

Cap values?
Title: Re: Uproar... Mid boost noise
Post by: madbean on April 01, 2013, 11:55:13 PM
Could be just too much gain causing some oscillation. It might get more prominent with the mid range boost on. Try cutting R5 down to 470k - 680k and see if that stops it.
Title: Re: Uproar... Mid boost noise
Post by: stecykmi on April 01, 2013, 11:57:58 PM
dunno man, it could be lots of things. use an audio probe and try to find what gain stage the squealing starts.  being a high gain circuit, you need use either a battery or a high-quality power supply as it will be very prone to noise with an unreliable power supply.
Title: Re: Uproar... Mid boost noise
Post by: gtangas on April 02, 2013, 08:45:23 AM
Ok I will try swap r5 and see what happens

Thx guys
Title: Re: Uproar... Mid boost noise
Post by: gtangas on April 03, 2013, 03:22:04 PM
Changed the R5 to 470k and played for bit and can't hear the oscillation...


Hope it is solved

Love this animal