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GK rails in a pedal?

#741
Dominic D said:
If I've offended anyone, I sincerally apologize. That was not my intention. If John and Frank wish for me to stop building these pedals, I will oblige.
Click to expand...

I can't imagine how anyone could be offended. Not to mention you assisted in correcting the schematic as well, so I really don't see a problem. I know I'm not one of the designers, but it doesn't appear that they have an issue with you. Seems like the backhanded comment came from someone other than the guys who designed it.

Please please please don't let this thread turn negative!!!! Two guys worked out building this circuit, they posted the schematics for anyone to use, some corrections were made, and a couple of people offered to build for others who chose not to do it for themselves. That's all I see here. If the designers chose to keep the schematic close to the vest, that would be totally understandable. However, they didn't and that is that. This is a wonderful project, let's keep the positive vibes going!
 
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#742
Si-bob said:
Sorry Frank, I'm going to ask for you to elaborate here, I'm still early in my electronics knowledge :).
By 'leave Z & Y open', do you instead mean that the output of the boost goes straight to R10s junction and the R13 junction simply straight to pin 3 of the IC?

Again, sorry if I'm missing something basic here

Thanks
Si
Click to expand...

What I meant by "leave Y & Z open", is leave Y & Z unconnected when not using the distortion detector. The distortion detector monitors the Y and Z points of the main circuit and when Y and Z are not equal the distortion detector lights an LED to indicate distortion.

This is what the schematic would look like without the dist detector installed:

NO DD.jpg

You don't have to install the Q89 boost either, if you do not use the Q89 boost then install C3. If you do use the boost, then replace C3 with the boost circuit. The schematic was drawn with the different options that we came up with as the circuit evolved.

The boost circuit also has a C3, but they are different C3's.

-Frank
 
#743
boomertech said:
What I meant by "leave Y & Z open", is leave Y & Z unconnected when not using the distortion detector. The distortion detector monitors the Y and Z points of the main circuit and when Y and Z are not equal the distortion detector lights an LED to indicate distortion.

This is what the schematic would look like without the dist detector installed:

View attachment 593284
You don't have to install the Q89 boost either, if you do not use the Q89 boost then install C3. If you do use the boost, then replace C3 with the boost circuit. The schematic was drawn with the different options that we came up with as the circuit evolved.

The boost circuit also has a C3, but they are different C3's.

-Frank
Click to expand...
Ok, devil's advocate here, but I'm just wondering. If the boost is optional, and some people want top jacks, could the boost be removed and then have top jacks? Like I said, just wondering. I have the pedal, love the pedal, but it IS a bit unwieldy on a pedal board. It's worth tailoring the board to this pedal, though!
 
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#744
kleinenenten said:
Ok, devil's advocate here, but I'm just wondering. If the boost is optional, and some people want top jacks, could the boost be removed and then have top jacks? Like I said, just wondering. I have the pedal, love the pedal, but it IS a bit unwieldy on a pedal board. It's worth tailoring the board to this pedal, though!
Click to expand...

The circuit without the boost is the "mini 800RB" power amp only.

The Q89 boost circuit is physically on the 800RB preamp, but it is after the amps effects return jack. So if you want the 800RB from the effects return jack to the speaker output, you will need the Q89 boost. It is fairly common to think of the power section of an amplifier as everything from the effects return jack to the output.

-Frank
 
#745
boomertech said:
The circuit without the boost is the "mini 800RB" power amp only.

The Q89 boost circuit is physically on the 800RB preamp, but it is after the amps effects return jack. So if you want the 800RB from the effects return jack to the speaker output, you will need the Q89 boost. It is fairly common to think of the power section of an amplifier as everything from the effects return jack to the output.

-Frank
Click to expand...
Way too much tech talk for me! I'm assuming you're saying "No, the top jacks still wouldn't fit."
 
#746
kleinenenten said:
Way too much tech talk for me! I'm assuming you're saying "No, the top jacks still wouldn't fit."
Click to expand...

That's funny! There is never too much tech talk!:D

I haven't built this circuit, but if you look at the gut pix from John's builds there isn't much room inside even without the boost.

I guess you could always use a taller box to have more room for top jacks. Maybe John or Dom might have a suggestion for you.

-Frank
 
#748
I've just worked around the width of the pedal. It's in one of my OD loops, so I never actually stomp on it. I turn on almost all my pedals with my hand as I hook up the pedal board, and then activate each loop from the loop box. It's about the only pedal I actually "stomp" these days, so the top-mounted jacks aren't a big deal to me. The possibility just got my mind wandering, and I'm one of those people who just has to know, even if I have no practical application for that knowledge. Thanks for indulging me, gentlemen!
 
#749
boomertech said:
What I meant by "leave Y & Z open", is leave Y & Z unconnected when not using the distortion detector. The distortion detector monitors the Y and Z points of the main circuit and when Y and Z are not equal the distortion detector lights an LED to indicate distortion.

This is what the schematic would look like without the dist detector installed:

View attachment 593284
You don't have to install the Q89 boost either, if you do not use the Q89 boost then install C3. If you do use the boost, then replace C3 with the boost circuit. The schematic was drawn with the different options that we came up with as the circuit evolved.

The boost circuit also has a C3, but they are different C3's.

-Frank
Click to expand...

This all makes perfect sense! You're a gent, thanks.
Yes your schem omitting the detecting circuit is how I tried to explain the second time :)

Great, thanks all, will report back with a build hopefully.

Si
 
#750
Si-bob said:
This all makes perfect sense! You're a gent, thanks.
Yes your schem omitting the detecting circuit is how I tried to explain the second time :)

Great, thanks all, will report back with a build hopefully.

Si
Click to expand...

Happy to help! Sometimes a simple picture answers a lot of questions.

-Frank
 
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#751
This is cool...Looking forward to A/B-ing this with the real deal.

This concept is great if you want that GK sound but are sometimes work in amp-less situations.
 
#754
I only got to play with it for a little while yesterday after receiving it, ill have more time tonight and tomorrow to mess with it, and then over the weekend ill have some time to use it in a band setting.
*First Impressions*
doesnt sound like a normal overdrive/distortion/fuzz, but i would put it more in the fuzz genre than the others. more gain on tap than i had thought. you have to push it a bit for unity gain. sounds great, big and thick sounding. pretty responsive to dynamics, but still maybe a little compressed (it is a dirty pedal,nature of the beast. not as bad as some fuzz pedals.) responds well to different pickup placements. the boost feature is great and turns the pedal from already cool to over the top gain. i like that you can leave the boost on and turn the pedal on and off without hitting both switches. the high cut switch i didnt notice much difference in. a little, but at that frequency i dont have alot going on normally anyway, and i had the tweeter in my cabinet off durring the test.

gear used to test - Fender Jazz with Dimarizio model j's, GK mb500, schroeder 1515l.

i tryed to a/b back and forth between the boost channel on my mb500 and the pedal, and i could get them to sound similar (gain on head running 2pm-max), the pedal had a woolier sound. similar but slightly different. more tests on that to come as well.

i plan on doing some direct recording this weekend hopefully and ill put some stuff up.
 
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#755
Hello! Got MY DiCosimo GK 800RB today! Gorgeous graphics and for a pedal with no interal battery, heavy! Lots of guts packed into the little enclosure, and the matching color scheme and knobs make it a beautiful addition to the collection.

Chain: '74 P-bass, stock pickups, effects, into small 10" Yorkville 50watt combo (didn't have time for the big rig).

I'm listening back to JohnK's SoundCloud samples, which are what sold me on the pedal to begin with, and I have to wonder what his bass's output is, and how he got the gain so low with unity output, and how his soundclips are so smooth but thick. I couldn't coax the same sounds out of the pedal through my 50 watt Yorkville combo, but maybe the amp itself is part of the problem?

My findings so far (only a few hours) are very similar to Sahe_Bassists, in that Unity volume seems to be pretty high on the knobs. I couldn't get a particularly Low Gain setting out of it and still have anything like Unity volume, even rolling the Vol knob on the bass back. The Input knob had to be around 10oclock and the Output knob at 5oclock (all the way up) to feel unity for me with less than heavy distortion.

I tried running a few things before it, mainly a Wooly Mammoth, a Digitech bass Synth set for Octave Down, and then Mammoth cascaded into the Synth Octave Down cascaded into the GK, and it appears that the GK takes all that level and just swallows it up, I couldn't get unity gain out of the GK with all those intense lows being hammered in to it at any setting. I know that MASSIVE VOLUME isn't the point of this pedal, just my findings so far.

It feels like the GK needs to be very close to first in line, with high-output pedals AFTER it in the chain, otherwise the compression just squashes it. For the record, the Yorkville amp WOULD reflect the massive volume changes when the GK was bypassed, the GK just couldn't pass on the volume when either pedal was pushed before it. Maybe I'm forgetting something fundamental about this pedal and where it needs to be in the chain, etc. Please let me know, everyone! Been watching this thread since the beginning and I am very excited to keep working with this good looking little box!
 
#756
Maybe the low distortion sounds involve using the boost to attain unity? Just asking, as I've never tested mine this way. I use mine as a mild fuzz, so unity is attainable, though definitely higher on the output knob than expected (3:00). Still, amazing pedal, and I can definitely get heavier or a bit lighter, and it sounds great pushing other effects for some great stacked tones.
 
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#759
ZombiCrow said:
You are probably right, at first I was using the boost as a Boost, but in the original circuit it's sort of always on, right? ....
Click to expand...

The Q89 boost is always in circuit on the GK 800RB. The GK's boost switch selects between the setting on the boost pot to what the pot setting would effectively be at its minimum setting.

-Frank
 
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