Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => Amplifier Discussion => Topic started by: pancho510 on March 09, 2011, 07:49:48 PM

Title: noisy cricket II tone issue
Post by: pancho510 on March 09, 2011, 07:49:48 PM
my first amp build went with the noisy cricket.
the amp sounds great but when I try to turn the tone
clockwise about a 1/4 of turn the amp will cut in/out
get real fuzzy sounds not playable at all. also not
sure if related but the grit switch has very little if any affect
on the sound but the gain works fine.
I built this with the radioshack board and parts.
use all info from Beavisaudio
Title: Re: noisy cricket II tone issue
Post by: bry melvin on March 10, 2011, 01:24:26 AM
Never built a noisy cricket...but...I do a lot of guitar and amp work. Have you tried another pot for the tone.Those cheap pots are really easy to cook with soldering; after doing thousands of solder joints I still occasionally cook one if I'm not careful soldering in a crowded area. If that is what happened (check the pot) get a pair of hemostats or an alligator clip to use as a heat sink when soldering. Check the switch for continuity too if it's a small switch you could have cooked that too!
Title: Re: noisy cricket II tone issue
Post by: pancho510 on March 10, 2011, 12:16:23 PM
thx for the info. after reading more post on this amp I seem
to have the same problem as others. the 3 pots cant be turn
up at the same time. I checked the tone pot for resistance
and it seems fine, is there a way check these pots to see if
its bad? I think the tone pot is bad because you can hear
a audio click noise at the same point when turning. will change
it out today.
here a link
http://www.beavisaudio.com/projects/NoisyCricket/MarkII/NoisyCricketMarkII_RadioShack_Rev2.pdf
I built mine just like the schematic says
anyone has ideals on what I should change caps/pots/res value
also I used a nine volt battery I might try play around with different
power supplies any ideal here? thx
Title: Re: noisy cricket II tone issue
Post by: polo16mi on March 10, 2011, 04:50:15 PM
Maybe you can try the next:

First change the tone pot for a 100K resistor between both 100nf caps, and see what happens with all the other pot at max.

Second part: Change the above resistor by a jumper, and see again what happens with the others at max.

If nothing bad with both test, then the pot is guilty, else look for other place.

Maybe you need to take in count, that in datasheet of LM386, when you short pins 1 and 8, is for max gain of the chip, they suggest you to put a 10uF electrolitic capacitor between this pins. (positive with 8, negative with 1). Perhaps it cause the trouble..? ...Not sure, but one more test that you could try.

By the way.... obvious think first......double check all conections.....specially pot conection, i mean, check where you conected each wire at pot tips.
Title: Re: noisy cricket II tone issue
Post by: J M Fahey on March 11, 2011, 12:21:26 AM
I think your amplifier starts to oscillate with high gain and tone on "bright".
Probably a layout , shielding or grounding problem, difficult to solve by "remote control".
Did you build it in a metallic grounded enclosure?
Title: Re: noisy cricket II tone issue
Post by: pancho510 on March 11, 2011, 01:59:20 AM
Quote from: J M Fahey on March 11, 2011, 12:21:26 AM
I think your amplifier starts to oscillate with high gain and tone on "bright".
Probably a layout , shielding or grounding problem, difficult to solve by "remote control".
Did you build it in a metallic grounded enclosure?
I think you might have found the issue.
I didnt think about shielding at all didn't even put it in a enclosure.
I got out my bread board today to change and test diferent parts.
this amp sounds good at lower tones but as soon as turn up the
tone it cuts in/out and all fuzzy. even the volume workes great til about 9
then cuts out. the gain really confuse me with a grit switch installed.
I thought I couldn't tell much different with the switch.
it turns out it sounds best with the switch on nice beakup but with
switch off it gets a little fuzzy and cuts in/out when gain is turn up
not clean sound at all. so I decided to take it apart and start over.
I was going to build the smokey tone amp on a bread board and once
I felt it sounds right start adding tone control/gain/volume one step at
a time. but it sound like shielding might be a issue. how do go about
testing out a circuit before you build it into a enclosure
Title: Re: noisy cricket II tone issue
Post by: joecool85 on March 11, 2011, 09:00:20 AM
Quote from: pancho510 on March 11, 2011, 01:59:20 AM
how do go about
testing out a circuit before you build it into a enclosure

I don't know about everyone else, but I frequently jump in head first and build the whole thing enclosure and all on my first build.  Not for the weak of heart, it can be disappointing if you aren't careful.
Title: Re: noisy cricket II tone issue
Post by: bry melvin on March 11, 2011, 10:42:37 AM
Quotehow do go about
testing out a circuit before you build it into a enclosure
My personal solution is an Epiphone  blues custom 24" steel chassis. it has 3 octal 5 9 pin holes and mout points for lots of pots and switches. is large enough to mount nearly any thing including breadboards in it AND put transformers outside. It also sets in a 10 by 8 by 36 "blank" plywood head cabinet that the chassis opening is lined with speed tape (heavey metal tape) for shielding.

I can build almost ANY AMP in that
Title: Re: noisy cricket II tone issue
Post by: pancho510 on March 11, 2011, 12:05:27 PM
Quote from: bry melvin on March 11, 2011, 10:42:37 AM
Quotehow do go about
testing out a circuit before you build it into a enclosure
My personal solution is an Epiphone  blues custom 24" steel chassis. it has 3 octal 5 9 pin holes and mout points for lots of pots and switches. is large enough to mount nearly any thing including breadboards in it AND put transformers outside. It also sets in a 10 by 8 by 36 "blank" plywood head cabinet that the chassis opening is lined with speed tape (heavey metal tape) for shielding.

I can build almost ANY AMP in that
any pics of that sounds like something i would want to build.
like most people here I want to learn how these things work
wanted to start small next build a small tube amp and so on.
but I need to be able swap out componets/add things
thanks for all the replies
Title: Re: noisy cricket II tone issue
Post by: pancho510 on March 12, 2011, 04:01:05 PM
I figured out what the problem was I had the input/output jacks
wired wrong hot and ground reverse. thats a little embarrasing :-[
not sure how it even worked at all. I built it on a breadboard and
it sounds really great  surprised by the sound I'll mess around
with different tone circuits and the gain.
next project will be the "murder one" 6111 tube
Title: Re: noisy cricket II tone issue
Post by: joecool85 on March 13, 2011, 05:16:56 PM
Quote from: pancho510 on March 12, 2011, 04:01:05 PM
I figured out what the problem was I had the input/output jacks
wired wrong hot and ground reverse. thats a little embarrasing :-[
not sure how it even worked at all. I built it on a breadboard and
it sounds really great  surprised by the sound I'll mess around
with different tone circuits and the gain.
next project will be the "murder one" 6111 tube

Glad you've got it figured out.  You'd be surprised how many of us have made silly mistakes like that...even now when we are not paying enough attention.   :P
Title: Re: noisy cricket II tone issue
Post by: pancho510 on March 15, 2011, 11:36:17 PM
ok had fun with this amp I tried to add 2 control circuits with no luck.
again im new to this I've looked at several scrematic on tone control
i'm just not getting it.most show a in and a out.
but the way the tone is on the noisy cricket there is only a in no out
I think. the tone is in parallel with the volume. can some one give me
a crude schematic of 2 tone controlls that will work with the noisy cricket
or/and some links of info on tone control that might help me
thanks frank