digi verb distortion

[El Heisenberg]

I just put together the digi verb kit from ggg.com and it is distorting a bit. It uses the little digi-log brick thingy. I run it on 9v battery, could it just be weak battery? I used a new one and it already measures 8.2 v but it distorts a little with a new battery still. Could it be cold solder joints somewhere? Or is this just a pitfall in the design?

[biggy boy]

Hi

I finished my kit from GGG about three days ago and it sounds good, NO distortion.
I'd give it a good going over with a magnifying glass and check your solder joints.
Also recheck to make sure you have the right resistors in the right spot. I got a pair of mine mixed up and had to swap them around.

Glen

[petemoore]

  dunno if this is applicable, I read something about the chip using a 5v supply.

[El Heisenberg]

Its got the 5v IC in it. All resistors are correct. It eorks but theres a little distortion when i play a little hard. What woild i be lookong for with a magnifying glass?? I already checked for solder bridges, is there a way to tell its a cold joint?

[El Heisenberg]

h unless the layout on ggg is wrong, then everything is in its plave. No solder bridges. Unless its a cold jointnor somethin, but i melted all of them again and it still distorts.

[petemoore]

I just put together the digi verb kit from ggg.com and it is distorting a bit.
  When...? Is it source-level dependant [only stronger signals make it distort]?
   It uses the little digi-log brick thingy. I run it on 9v battery, could it just be weak battery?
  Send the battery along, and I will measure it's voltage, nah might drop with travel stress...or...how does it taste..sharp ? weak ?
  I used a new one and it already measures 8.2 v but it distorts a little with a new battery still.
  Certainly, starting with 9v is worth a try.
  Could it be cold solder joints somewhere?
  Yes.
  Or is this just a pitfall in the design?
  I don't like pitfalls.
  But when I saw the chip, 5v supply, first question is does it distort w/big signal inputs. Then I figured...sure could wet down some of these amps I have around here, poppin' the chip into a board with pre-gain control/post boost circuit would probably allow larger input signals to pass without hitting [or being 'attracted to'] a rail.

[El Heisenberg]

I just put together the digi verb kit from ggg.com and it is distorting a bit.
  When...? Is it source-level dependant [only stronger signals make it distort]?
   It uses the little digi-log brick thingy. I run it on 9v battery, could it just be weak battery?
  Send the battery along, and I will measure it's voltage, nah might drop with travel stress...or...how does it taste..sharp ? weak ?
  I used a new one and it already measures 8.2 v but it distorts a little with a new battery still.
  Certainly, starting with 9v is worth a try.
  Could it be cold solder joints somewhere?
  Yes.
  Or is this just a pitfall in the design?
  I don't like pitfalls.
  But when I saw the chip, 5v supply, first question is does it distort w/big signal inputs. Then I figured...sure could wet down some of these amps I have around here, poppin' the chip into a board with pre-gain control/post boost circuit would probably allow larger input signals to pass without hitting [or being 'attracted to'] a rail.

I tried the battery. Im not sure what you mean by that last part. So i cant play a big muff through this thing without it distorting? Or u saying i could alter or add to the circuit to fix this? The distortion is bad sometimes and not musical. The thing works tho. I didnt mess up that bad.You cant hear the distoroon through a little tiny 1/2 watt ms-2,but everything else u can.

[MarcoMike]

the thing is: with 5 volts of headroom (which is definetly a overextimation) every signal higher than 5 V peak to peak WILL distort badly. even lower signals actually. this is why Petermore suggested: lower the input before the 5V section, then boost back to unity after it.
if your circuit distorts even with a simple (passive) guitar signal as input, no boost or else in front, then there might be something wrong in the circuit.

[El Heisenberg]

But what could be wrong??

If this is such a problem why isnt that fix in the original design??

So youd have be lower the input by fixed resistor in series? Then boost with a simple jfet boost or somethin? Id beed a little more guidance to do this i think.

[anchovie]

You need to provide information on the whole setup:

Are you running straight into the reverb?
What guitar have you got?
Single coils/humbuckers?
Active/passive?
Are you still using batteries that appear to wear out quickly or have you tried a mains adaptor?

[El Heisenberg]

Yea i dunno how to do this. Lookin at the schem, i cant tell where the audio signal is going through the 5v regulator chip.

[anchovie]

Yea i dunno how to do this. Lookin at the schem, i cant tell where the audio signal is going through the 5v regulator chip.

The audio doesn't go through the regulator. The regulator turns the 9v power supply into 5v for the reverb brick.

[El Heisenberg]

You need to provide information on the whole setup:

Are you running straight into the reverb?
What guitar have you got?
Single coils/humbuckers?
Active/passive?
Are you still using batteries that appear to wear out quickly or have you tried a mains adaptor?

Yes im running straight into the reverb. I have pedals before it but its true bypass

No name guitar i dunno why this would matter. My guitar isnt broken. I have other reverb pedals. It works fine through those.

Humbucking pickups in parallel. Passive. If i were active i woulda mentioned so, and woulda looked at tht being the problen first.

The batteries arent cheap. I woulda mentioned if they were weird batteriea and once again, would have first looked at that to be the problem. Duracell batteries. Should be fine. No ac adapter, everyone ive tries hums in everything i plug it into. No real boss type adapters. Im positive this would do nothing.

[El Heisenberg]

So does he mean to lower the input beforebthe entire circuit and boost back up after the brick or the rest of the circuit?

[anchovie]

Yes im running straight into the reverb. I have pedals before it but its true bypass

No name guitar i dunno why this would matter. My guitar isnt broken. I have other reverb pedals. It works fine through those.

Humbucking pickups in parallel. Passive. If i were active i woulda mentioned so, and woulda looked at tht being the problen first.

The batteries arent cheap. I woulda mentioned if they were weird batteriea and once again, would have first looked at that to be the problem. Duracell batteries. Should be fine. No ac adapter, everyone ive tries hums in everything i plug it into. No real boss type adapters. Im positive this would do nothing.

I didn't suggest your guitar is broken. It helps get an idea of what strength input signal is going to the reverb. Humbuckers have a much higher output than single coils. Active pickups are a higher output too, again it's not questioning whether they're broken or not.

I didn't ask if your batteries are cheap or weird, I asked if you had tried a mains adaptor. Doesn't matter if they're Duracell, it was you who said in your first post that "a new one already measures 8.2v". Digital stuff sucks the juice out of batteries fast. Get yourself a decent regulated 9v adaptor that doesn't hum.

Have you tried making an audio probe to see if the distortion occurs before the signal enters the reverb brick?

[anchovie]

So does he mean to lower the input beforebthe entire circuit and boost back up after the brick or the rest of the circuit?

There's already an op-amp that applies some gain before the signal enters the reverb. Lowering the feedback resistor could help, unless the distortion is occuring before this point.

[MarcoMike]

what if you roll back the guitar volume pot?? is the distortion going away?