Decimator Gstring Debug / Help!

[DIMstompboxes]

Hey , nice job Roger. I took the easier route and put a Vert trimmer in.  I got mine working a couple of days ago...Just to mention one point,  I was almost caught out

by useing my test rig which has no send/return sockets. It didn't work obviously, so I had to put a jumper in the circuit  send/return.

It probably won't catch you out...but somebody with not much experience might not know.

I haven't had time to box it yet, but its going to be a useful pedal it works a lot better than the other noise gate we were doing

Hope yours works great...let me know.

Mike

Cool, I just received my package and drilled the case, will let you know buddy

[DIMstompboxes]

Hi Harold,
Just to clear out on your posted layout corrected LABEL version


IN is guitar IN
SEND is guitar OUT?
RETURN is DEC IN
OUT is DEC OUT?

or
IN is guitar IN
SEND is DEC OUT?
RETURN is DEC IN
OUT is guitar OUT?

Furthermore, the posted (by lars-musik) outboard wiring layout seems to use only mono jack socket for both SEND/RETURN. Is this correct?
I don't have stereo socket as of now, but can I follow this outboard wiring layout then use mono for both SEND/RETRUN and just put one dummy loop cable? when nothing is connected on send/return.
Here:



Cheers,
Roger

[lars-musik]

Yes, you are right. Strange enough, both scenarios are possible.

Attached you'll find the enclosure etching mask for my build. The jacks are labelled and the setup can be either ,,A", which comprises an effect chain or ,,B" if the pedal is put into the amp's effect loop. Depending on what you are wiring Dec Out or Guitar Out might be the Output.
For an even better illustrated version try this document: http://c3.zzounds.com/media/DecimatorGStringPedal5-13-092-f97fb869826356c1371242dac86f4cc8.pdf

However, if you want to run the Decimator in Un-G-Stringed-Mode , you'll have to run a patch cable from ,,Guitar out" to ,,Dec In" and connect ,,Dec Out" to your amp. This way you'll have a "standard" noise gate to be put at the end of your effect chain. A more elegant way to avoid that patch cable would be to use a switched jack for Dec In or simply a switch to make that connection if needed..

I hope that helps.

Best, Lars

[DIMstompboxes]

Thanks goodness Lars you're still with us following this thread 
I just figured out by reading your link Gstring PDF manual and by reviewing Joao galego schematic diagram routing I concluded this following Harold's corrected labels

IN = guitar in
SEND = DEC(imator) OUT
RETURN = DEC(imator) IN
OUT = guitar out

In my mind, this follows also those multifx unit as follows:

unit IN, unit SEND, unit RETURN, unit OUT

Let us do furthermore brainstorming on this and hear what Harold, fendman(Mike) so with you Lars and with other too. Its kind of late
Hope to hear from all of you....
Cheers,
Roger

[Harold]

The wiring diagram with the GUIT IN and GUIT OUT connected doesn't use a buffered output/send. I strongly advise against using that, but using my PCB with buffered GUIT OUT (aka SEND) instead.

[lars-musik]

Hi Harold,
could you explain why the buffers are important in that particular case? I tried to work through all the postings  in this tread and I am just a little astonished that there is obviuosly quite a lot to improve (different values, missing pads etc) since Galego published his layout. I have build two of these pedals for my setup following this" un-improved old version" and both work just fine.
Best, Lars

[Harold]

Hi Harold,
could you explain why the buffers are important in that particular case? I tried to work through all the postings  in this tread and I am just a little astonished that there is obviuosly quite a lot to improve (different values, missing pads etc) since Galego published his layout. I have build two of these pedals for my setup following this" un-improved old version" and both work just fine.
Best, Lars

Passive splitting of your signal wil cost you half of your signal. If you're behind a buffer that's no problem, then the buffer will supply more signal, but passive ... and you have a buffered signal available, so why not use it?

See also the thousands of discussions about the passive "Tuner out" on volume pedals.

[fendman]

I am sticking with Harold's diagram its the most simple...in,out, send return.  This DEc in Dec out is just confusing me

Mike

[DIMstompboxes]

Yes Lars, you splitted your signal as per your wiring for GUIT IN and GUIT OUT and weaken the signal into (passive). The U7.1 buffer signal out (active) is better see diagram for active (strong) splitting of signal for both send and U7.2 signal input.

I already bought 1/4" mono 2 conductor jack socket with TIP is SHUNT for (DEC out send/DEC in return) and will connect both SHUNT terminal as per diagram so that when nothing is connected to send/return it stay closed.

@ Mike, my logical thinking if I'm right.... the diagram is an upgrade from regular Decimator diagram into Gstring diagram only the send/return is new, so I'll still stick with (IN) as guitar IN and (OUT) as guitar OUT... and the (SEND) as DEC OUT and (RETURN) as DEC IN using Harold's PCB.  See if I can update you all afterward.   

Appreciate more discussion from you guys.

[DIMstompboxes]

Performance is the same with my CA3080 downward expander on the front of the chain only this one has send/return.  I test it both with my Boss NS2 on send/return setting, NS2 has better decay in sustain note due to NS2 has DECAY control.  Maybe its too early for me to comment and I need to adjust the trimmer more for much better result.
Version "B" works exactly the same with version "C" 
I used one TLE2072 and one LF353 for dual amp, two LF347 for quad amp.

Cheers,
Roger

[Harold]

Maybe its too early for me to comment and I need to adjust the trimmer more for much better result.

The trimmer only sets unity volume, nothing else.

[DIMstompboxes]

Maybe its too early for me to comment and I need to adjust the trimmer more for much better result.

The trimmer only sets unity volume, nothing else.

Yes its easy for me to adjust by comparing the volume level between truebypass(OFF) and switch(ON) volume level but there were some area in the trimmer with either abrupt or stuttering sustain note! (no decay or stammering decay). Unlike my Boss NS has THRESHOLD knob with additional DECAY knob control. 

[Adriano]

Is someone can post final voltages of amp's pins. I'm fighting with the distrortion on THAT's 8th leg in G-string version.
I'll be grateful for any sugestions.
Thanks.

Cheers

[Justus]

I know this thread is old, but it's basically got the only/best information on the Decimator G-String clone that I can find.  Thanks to everyone who has worked on this circuit!  I am planning to build one soon.

My question lies with the last discussion of the jacks.  The way I have reviewed the layout, it appears that they would be as follows:

IN = Guitar In (guitar plugs in here)
SEND = Guitar Out (goes to other fuzz/OD pedals, then Amp)
RETURN = Decimator In (signal directly from the FX Loop on the Amp, i.e. FX Loop Send)
OUT = Decimator Out (goes to remaining effects in the Amp's FX Loop, if any, then to the FX Loop Return)

Is that right?  If so, that also means that to minimally test the pedal (rock-it-before-you-box-it) you'd have to jumper the SEND and RETURN pads, leaving IN and OUT as your effect pedal's In and Out, right?  Also, how would you do offboard wiring with a 3PDT daughter board with the normal In, fxIN, fxOUT, Out pads?

[wileres]

I've assembled this noise gate, works very well.
I play with my peavey 5150 combo and guitar with emg pickups and its noiseless but I don't miss sustain. Thanks to everyone who helped made this great pedal. 

Thanks a lot

Wil from Catalonia

[Brejna]

I know this thread is old, but it's basically got the only/best information on the Decimator G-String clone that I can find.  Thanks to everyone who has worked on this circuit!  I am planning to build one soon.

My question lies with the last discussion of the jacks.  The way I have reviewed the layout, it appears that they would be as follows:

IN = Guitar In (guitar plugs in here)
SEND = Guitar Out (goes to other fuzz/OD pedals, then Amp)
RETURN = Decimator In (signal directly from the FX Loop on the Amp, i.e. FX Loop Send)
OUT = Decimator Out (goes to remaining effects in the Amp's FX Loop, if any, then to the FX Loop Return)

Is that right?  If so, that also means that to minimally test the pedal (rock-it-before-you-box-it) you'd have to jumper the SEND and RETURN pads, leaving IN and OUT as your effect pedal's In and Out, right?  Also, how would you do offboard wiring with a 3PDT daughter board with the normal In, fxIN, fxOUT, Out pads?

Is this final way of routing? I've read everything few times, send should be guitar out if using it with amps loop, right? If not, jumper send and return and dec out is guitar out..

[Brejna]

Any idea how to add decay knob? 

[luciano]

hello guys I have a problem  ... pretty much the sound is saturated, almost like a fuzz, if you increase the threshold at the beginning increases the volume, then lowers abruptly. then it does not work at all well, I looked to see if there were courts or bridges, and no, I do not understand the problem, with the sound probe I saw that the signal comes clean, and up to ic in charge of the loop sound is spotless, the problem arises after the resistor 5,1k coming out of 100nF connected to pin 1 of lf347. immediately after the diodes, the signal is distorted.

[Mark56]

Hi, is anyone still available to help on this topic?

I built the non G string version from here: http://www.sabrotone.com/?attachment_id=1380 which works just fine so I then built the G string add-on found here: http://diy-layout.com/75. Signal passes cleanly to guitar out, but when linking that to DEC Return there is no signal from DEC Send, so it appears the gate is staying open no matter where I set the threshold.

Put it back to non G string and it still works ok. I have done a thorough check on the add-on board and there are definitely no errors, I also put the Op Amp into the main board to check it and it works fine.

Any help would be appreciated.

[slacker]

Are you connecting it in the right place? On the add on where it says "U7.1" it should be U5.1, which is the bottom of what was C3. "R2" on the add on connects to what was the top of C3. If you connect it like that and connect send to return it should function like a non G string, does it do that?