Mini Booster questions

[soggybag]

I built a Mini Booster from AMZ, it's working well, but there is humm, really more of a buzz. I'm trying to track down the source of the noise. It's the same in a box or out. The noise cuts out if I touch the output jack?

Give me some suggestions. I'm guessing it's some sort of ground issue. Which narrows the possibilities to something less than infinite.

Other than the noise it sounds pretty good. Great boost, with a little grain or something in there.

A second question. C2 on the AMZ schematic, seems to be an odd value 3.3uf NP. I remember reading that Jack chose this part because it was in his parts bin at the time. I've also read, around here, that any size cap will work here, .1uf was suggested. Is this part sound critical?

[snoof]

That cap effects the bass content, smaller = less bass.

[fuzzo]

I have a question about this mini booster. It's a clean booster or an overdrive ? Maybe a clean booster which can drive amp like overdrive.

I ask that 'cause I saw a youtube video of the fulltone fat boost (same schema, amz mini booster) to listen the sound of this boost, and I found the sound is very satured with the some settings.

it existes modifications of this  boost, to transform it to overvride ?


thanks

(I don't create a new topic for this only question)

[petemoore]

I have a question about this mini booster. It's a clean booster or an overdrive ?
  It is not a clean booster.
    Maybe a clean booster which can drive amp like overdrive.
  Can drive amp, plenty of output. Adds a touch of...Jfet non-clean [distortion, ~small amount].
  I ask that 'cause I saw a youtube video of the fulltone fat boost (same schema, amz mini booster) to listen the sound of this boost, and I found the sound is very satured with the some settings.
  Yeap, IIRC it amplifies more LF content than Jacks schematic.
  it existes modifications of this  boost, to transform it to overvride ?
  See GEO> RG's 'mu amp' article.
  The gain and output levels can be 'altered', don't know that I'd call it transformed to OD though.
  It 'cleans up' [which is a misnomer] my FF...takes the 'coarse rasp tone' out of the FF, very nice, favored settings.
  The minibooster drives and gets driven really nicely as is, I have tried various mods for gain etc., the ones I kept cut more LF's than the capacitors values shown at AMZ.

[fuzzo]

Thanks for your answers, peter!

I don't understand, you say isn't a clean booster but in the AMZ's page, it's said it is a clean boost. But it's true when I saw the vids it's more a kind of big crunch/overdrive for me. Beside the fulltone has  more controls than a traditional booster which has just one volume knob, espacily the "input gain", which make me think it's like an OD.


Actually, I'm looking for a pedal (diy project of course) to have a more fatty and punchy tone, something more dirty than a standart clean tone, a kind of big crunch with balls. This pedal seems to be great for that  ( I say that in seeing the vidéo of the fat tone's fulltone, I didn't find samples for the mini booster's AMZ).

[kurtlives]

I built a Mini Booster today... this thang aint a boost. Its a mean overdrive.

I have only tested it on a 75W SS amp though.

Has so much output... unity gain for me was at 1030 (knob wise).

[kurtlives]

Maybe someone can answer this for me...



What are A and B?

[petemoore]

  A is a source follower output
  B is Gnd.

[MikeH]

A and B is a switch, although nobody seems to report any audible difference whether it's engaged or not.

[kurtlives]

Hmm just bypassing that 10mF cap.

Dosent that cap just boost all frequencies? Similar to the cathode bypass combo cap.

[petemoore]

 and would be shorting across the S resistor, connecting S to ground.
  I can't see any AC advantage with the large bypass capacitor already there.

[fuzzo]

kurtlives, you've just installed a volume pot, nothing more ? So for you isn't a booster, more an overdrive ?

Ok guys, so it's really an overdrive, my impressions were corrects. It's seems to be cool and really easy to build. Someone have did a striplayout (I din't find one in the layout gallery) ?Or I must make one ? (i'll post it, of course)

Good night guys and thanks again!

(the good thing with this forum, my english is in progress! )

[kurtlives]

kurtlives, you've just installed a volume pot, nothing more ? So for you isn't a booster, more an overdrive ?

Ok guys, so it's really an overdrive, my impressions were corrects. It's seems to be cool and really easy to build. Someone have did a striplayout (I din't find one in the layout gallery) ?Or I must make one ? (i'll post it, of course)

Good night guys and thanks again!

(the good thing with this forum, my english is in progress! )

Ya its definatley a overdrive or some "grit" unit.

PMing you a layout.

[fuzzo]

ok, I make a striplayout and I post it here.

[amz-fx]

What are A and B?

The answer is right below the schematic:

http://www.muzique.com/amz/mini.htm 

regards, Jack

[fuzzo]

What's the use of the input cap (5nf) ? We can remove it or not ?

[kurtlives]

You need an input cap. I believe with that size it isnt coloring your tone muhc anyways.

It blocks DC signal from getting in.

[fuzzo]

It's done :



If you see mistakes, say me.

[fuzzo]

Any reposts;

I've just did this just for myself ?

[petemoore]

  I almost built another one today, this MB has been giving me the 'on and off's [off being the output level drops, go figure, I have].
  But this time I think I've got it figured out to where maybe it'll be 'on - on' when I want it to [just like last time I tried to debug it].
  Point being I'll have a good minibooster, if I have to build another one, ok, giving this board a last try.