ISP Decimator G String Problems

[zanshin777]

I bought a ISP Decimator G string pedal. I use it for both FX Loop and in-front-of-the-amp in the same time.
The pedal is last in the chains as suggested. (Both FX LOOP and in front of the amp.)

In Front Of The Amp : Wah --> Overdrive --> G String
FX Loop : Delay --> G String

Amp : Marshall DSL5C - 1 Watt Mode - Red Channel - Volume at 8.5 : Gain at 10

I have three issues about the pedal.

1) G String removes the delay pedal repeats. How to use G String with the delay pedal?

2) For what channel do I adjust the threshold level?

For drive channel the threshold level is optimum but when I switch to clean channel it cuts of the notes in that channel.
If I adjust the threshold level for the clean channel then the drive channel has "hum"

3) For drive channel when the threshold level is optimum still there is very slight "hum"

If I adjust the threshold level just a little bit more it cuts off the notes. Is that much of hum normal?

 

[megaup987]

Re: ISP Decimator G String Problems

I don't believe you have it set up correctly. The G String should be the first pedal in and the last after "noisy" pedals.
Reverbs, delays, etc should be after G String (this is essentially true for any noise reduction/gate).

The way it should be:
In Front Of The Amp : Guitar --> (Guitar In) G String (Guitar Out) --> Wah --> Overdrive --> Amp
FX Loop: (Dec In) G String (Dec Out) --> Delay

Essentially, what G String does is it tracks your guitar signal to trigger the gate. That's why it should go first. When the volume drops below a certain level and there's no signal in it kicks in the gate. That's why it removes your delay repeats.

Also, when you adjust Threshold level for the drive channel, do you have your Overdrive pedal on? That may cause the clean channel signal to be cut off then you switch back. Set it up the way I describe and then adjust the Threshold level for your drive signal. When you switch to clean channel, you should be fine.

 

[zanshin777]

Re: ISP Decimator G String Problems

Look what the Owners Manual says :

"The pedal should always be the last device in the signal chain."

Here is the pdf

http://www.isptechnologies.com/manuals/Decimator%20G%20String%20Pedal%205-13-092.pdf

 

[Hank-]

Re: ISP Decimator G String Problems

^I think it's better to stick with owners experience than owner's manual on this one.

Put your delay/reverb after the gate. Otherwise, as the repeats get quieter, the gate with block the repeats from fading out naturally.

 

[zanshin777]

Re: ISP Decimator G String Problems

Now I tried putting Decimator G String in the first both FX Loop and in-front-of-the-amp.

When Decimator is in the first;

In-Front-Of-The-Amp it kills sustain. If you decrease threshold then it hums loud. Horrible.

However in the FX Loop It doesn't kill delay repeats. Also delay sounds better. (I suspect slight hum originates from the delay and G String doesn't kill the hum of it. There is still slight hum.)

So I'll try putting the G String first in the FX Loop. However last in-front-of-the-amp. I'll tell the results.

 

[Hank-]

Re: ISP Decimator G String Problems

I don't think it's gonna remove mains hum, so some of it is normal. Plus are you using isolated psu or 1spot type?

 

[IMENATOR]

Re: ISP Decimator G String Problems

That document is only showing the scenario of od/distortion pedals so in that regard it is correct. It does not explain how to use an amp with an FX Loop. You can read this

http://www.isptechnologies.com/manuals/Decimator II G String Manual.pdf


If ou are only dealing with noise from OD and amp then you can try this,

Guitar > Wha Pedal > Decimator Guitar In > Decimator Guitar Out > Overdrive pedals > Amp Input > Amp FX Send > Decimator DEC IN > Decimator DEC OUT > Modulation pedals> Delay/Reverb pedals > Amp FX Return

In summary, anything between the decimator g string "Guitar Out" and "DEC IN" will be silenced when you don't play any note.

 

[megaup987]

Re: ISP Decimator G String Problems

In-Front-Of-The-Amp it kills sustain. If you decrease threshold then it hums loud. Horrible.

Of course it kills sustain. It's a gate. It's its job to kill noise and thus sustain. Once the input signal volume drops below a certain level the gate closes and everything, including hum and quiet sustaining notes get cut out.

Put in first in front of the amp, and before the modulation/reverbs/delays in the loop (as I described before). Have your amp and overdrive setup for the most amount of gain that you typically use. Roll the Threshold up slowly until there's no noise when you're not playing. Then roll it up more just slightly to set gate activation speed for your staccato notes. In any case, be prepared for reduced sustain (due to gate) and slightly reduced treble/presence (due to noise reduction).

I also recommend against putting a wah pedal in front of the G string. I'm not sure how it will react to ever changing "noise and signal profile" when the wah is active.

As IMENATOR correctly pointed out "In summary, anything between the decimator g string "Guitar Out" and "DEC IN" will be silenced when you don't play any note."

Hope this helps.


Also, how loud is your guitar typically? What pickups are you using? Are they wired correctly? Are there any grounding issues? Is the control cavity shielded (some argue it doesn't matter, but in my experience it makes a world of difference. my shielded guitars are now quieter than any guitar with EMGs I've ever used)?
If your guitar hums really loud without the G String, than the only solution (other than addressing the source of the problem) is to roll up the Threshold knob. But it will activate gate more aggressively, killing your sustain. There's just no way around it. That's just how gates work, especially with overdriven signal.

PS. Not sure on this forum's policy on posting links to other forums, but google "Decimator G-string cable layout?". Should be the very first link. That thread goes into great details on how to wire your G String. But essentially it says the same as was said here before.

 

[zanshin777]

Re: ISP Decimator G String Problems

I've noticed that you recommend that

you directly connect your guitar to G Strings' Guitar In (By putting OD between Guitar Out and Amp Input)

and

you directly connect Amp Send to G Strings' Dec In (By putting Delay between G Strings' Dec Out and Amp Return)

What's the difference between between this layout and putting the effects;

between the Guitar and G Strings' Guitar In

and

between Amp Send and G Strings' Dec In?

I've also experienced the Wah after G String doesn't sound right. I should do the Wah as you recommended.

 

[megaup987]

Re: ISP Decimator G String Problems

Do not put pedals before G String's Guitar In. G String uses Guitar In signal to trigger the gate. If you put noisy pedals before Guitar In (like overdrive), the G String will think that that noise is the normal signal and will not gate it out.
Similarly if you put your reverb/delay pedals before Dec In, your delay signal will be gated out.

If you're familiar with the concept of sidechain in recording, the gate resides between Guitar Out and Dec In, but it's being triggered by the Guitar In signal.

 

[zanshin777]

Re: ISP Decimator G String Problems

1) I put the pedals as you recommended. Before that the clean channel of the amp is terrible. Very muffled and dark. Now it's good. Also very drastic change between bridge and neck pickups which is not good. Now that's good also.

However, even If I cranked the G String as full there is still slight hiss. Is that much hiss normal?

My guitars are

+ Gibson LP Traditional With Seymour Duncan Slash Set
+ Ibanez RG470 With Seymour Duncan TB-6B, SCR-1N, APH-1B

Pickups are installed by a experienced guitar tech. Regular wired.

Guitar Volume and Tone Knobs are cranked. The results are the same with two guitars. Slight hiss.

G String and BD-2 Phat Mod are powered with original BOSS adapter. The others are powered with batteries.

Amp : Marshall DSL-5C. I use in 0.5W mod. Red channel. Gain 10 Volume 8.5

2) Why do you put the wah between the guitar and G Strings' Guitar In rather than G Strings' Guitar Out and Amp Input?

3) Not horrible as before but still it cuts the sustain. Can A good compressor help me to get back the sustain?

 

[zanshin777]

Re: ISP Decimator G String Problems

Is that much hiss normal for my setup?

I have to leave feedback where I buy it. If not I'll send it back.

 

[B2D]

Re: ISP Decimator G String Problems

I bought a ISP Decimator G string pedal. I use it for both FX Loop and in-front-of-the-amp in the same time.
The pedal is last in the chains as suggested. (Both FX LOOP and in front of the amp.)

In Front Of The Amp : Wah --> Overdrive --> G String
FX Loop : Delay --> G String

I'm gonna stop you right there.

I have one of these pedals - this is not the correct set up for this pedal.

The signal flow you want is as follows:

Front of amp:
Guitar --->Wah>OD>*ISP Guitar In*>*ISP Guitar Out* ---> amp input

FX loop:
amp send ---> *ISP DEC IN*>*ISP DEC OUT*> Delay ---> amp return



This allows the ISPGs2 to use the guitar input as the "trigger" for the gating curcuit, improving response time and dynamics. I believe it also buffers the signal going to the amp.

The actual reduction circuit is placed immediately after the amp send, so that's the first thing your gained up signal sees, then NR is done, then delays, verbs, etc do their thing, sending the signal back to the amp.

Try that setup instead. Play with the threshold knob until the hiss on the max gain channel JUST goes away, and that should be the optimal setting. I play with a 100W JVM head with gain and volume on about 6, and my rig is dead quiet if I'm not playing it right then. I only turn the ISP off if I'm playing on the green channels for most of a song or if I want controlled feedback.

 

[megaup987]

Re: ISP Decimator G String Problems

Front of amp:
Guitar --->Wah>OD>*ISP Guitar In*>*ISP Guitar Out* ---> amp input

What's the reason to put the Wah and the OD before the ISP Guitar In? Any hiss amplified by the OD will be viewed as "normal" by the ISP gate trigger, no? Same with the wah toe down position.

Just set it up like this: http://s272.photobucket.com/user/RachelPMorgan/media/Guitar Stuff/DecimatorSamplesetup.jpg.html

Black is in front of the amp, red is in the loop.

 

[zanshin777]

Re: ISP Decimator G String Problems

Do not put pedals before G String's Guitar In. G String uses Guitar In signal to trigger the gate. If you put noisy pedals before Guitar In (like overdrive), the G String will think that that noise is the normal signal and will not gate it out.
Similarly if you put your reverb/delay pedals before Dec In, your delay signal will be gated out.

If you're familiar with the concept of sidechain in recording, the gate resides between Guitar Out and Dec In, but it's being triggered by the Guitar In signal.

You said the other day like that. Today you said that you've put od, wah and tuner before G String Guitar In. (In the picture)

Now I tried both. I like sound of the setting which the wah before G String Guitar In and OD after G String Guitar Out. Both wah and OD sound better. Sustain fade out occurs more naturally.

However whatever I do there is still slight Hiss. Is that much Hiss normal? Should I send the pedal back?

 

[megaup987]

Re: ISP Decimator G String Problems

You said the other day like that. Today you said that you've put od, wah and tuner before G String Guitar In. (In the picture)

Look at the picture again, the guitar is connected directly to the G string Guitar In, and all the pedals go after that.

I like sound of the setting which the wah before G String Guitar In and OD after G String Guitar Out.

That's odd. Placement of the wah before or after G String guitar input should not affect the operation of the wah pedal. It would change how G String reacts, maybe. Unless for some reason you wah doesn't like to see the buffer in front of it, which, again, is odd.

However whatever I do there is still slight Hiss. Is that much Hiss normal? Should I send the pedal back?

What's the source of the hiss? OD? Amp? Is there still hiss if you turn the Threshold knob all the way up?

Try this:
Guitar --> ISP Guitar in --> ISP Guitar Our --> Amp In (turn to OD with high gain) --> Loop Send --> ISP Dec In --> ISP Dec Out --> Loop Return. Have only one pedal connected to the power supply as well. Turn the threshold knob up slowly until hiss is gone, and then up a little more to adjust how quickly it reacts. If all is good, the pedal is OK. If all is bad, then send the pedal back.

 

[zanshin777]

Re: ISP Decimator G String Problems

What's the source of the hiss? OD? Amp? Is there still hiss if you turn the Threshold knob all the way up?

Definitely. I cranked the threshold as full and there is still hiss. I gave my exact setup above. What do you think? What's the problem? Is there problem with this G String pedal?

 

[megaup987]

Re: ISP Decimator G String Problems

Try just the G string and the amp. If there's still hiss, then it's G String problem for sure

 

[B2D]

Re: ISP Decimator G String Problems

What's the reason to put the Wah and the OD before the ISP Guitar In? Any hiss amplified by the OD will be viewed as "normal" by the ISP gate trigger, no? Same with the wah toe down position.

Just set it up like this: http://s272.photobucket.com/user/RachelPMorgan/media/Guitar Stuff/DecimatorSamplesetup.jpg.html

Black is in front of the amp, red is in the loop.

I tried it with the guitar first in the chain, and the way I described. I seemed to prefer the ISP as the last thing before hitting the amp in the front - very subtle difference, but the guitar seemed a little livelier that way. The boosted signal triggering the detector seemed to make feedback a little more attainable while getting the threshold where I wanted it, especially if I was boosting a clean channel.

I recommend the OP try both and see what he likes more.

 

[zanshin777]

Re: ISP Decimator G String Problems

Lastly,

I plugged out send&return cables.

Pluged guitar jack into G String Guitar In and Guitar Out into Amp Input and there is still "Hiss"

Then the problem is G String. Right?

I will try sending G String back.