"Orange/Matamp" build: Green Citrus opinions

[traktop]

Looking for orange/matamp "amp in a box" fet build, I finally went for the "Green Citrus" http://guitar-fx-layouts.42897.x6.nabble.com/Green-Citrus-for-Orange-Lovers-tp9872p10063.html
I built the recommended Johnk´s final vero layout:


I´ve made 2 builds of this one and found them a little dissapointing from the "huge sound " kind of expectations.
I know that some mods were made to the tone stack to make it less bass flubby, but to me ended up being like the "tube screamer amp in a box" ,(compared to the bypassed sound of my les paul), but still being muddy sounding.
I think I will try reverting the bass tonestack cap to the original, (4n7 to 22n I think...), and radically downgrade the Q1 source to ground 47uf cap, (as Frank NH suggested on the thread), as I found this one being  a major culprit on turning this build muddy.
What are your thoughts on this build in general?

Anyway, any suggestion for an orange/matamp kind of build?

I remember johnk talking on the green citrus thread about an "Orange Citrus" build he made which had the tonestack before the gain section. I guess it is the "Citrus Graphic MKII " what he was talking about, right?
Cheers, Gilberto.

[rocket88]

to be honest with you looking at the build it's not really a matamp in a box, and nor do vintage matamps and vintage oranges sound the same dispite what people try to claim. while they were both designed by the same guy, look up the history of orange and matamp and you'll see what i'm talking about, there's a lot of differences between the two amps. if you listen to the actual amps they have their own character. old matamps are heavier and darker sounding compared to the oranges of the same vintage.  i searched a long time ago for the schematic for the amp for a planned turretboad amp layout, and it's damn near impossible to find as they're fairly rare.

but i digress, no johnk's modified orange isn't the same as this pedal i can guarantee that. listening to the clips people made it is a little dark, but so is the real amp. to get the tonestack closer to the real thing you can change the following parts:

bass2-bass1: 10nF resistor to ground 27k
treble2-trebl1: 330pF
68nF cap going into D of Q2 should be 47nF

that's just on a quick look over. but i can also tell you there's no drive pot, it's actually a switch a rotary switch, and it's missing the presence pot.

sorry for more of the rant, it just always bothers me when things are described inaccurately. btw, if you want to wait for it its actually on the list for the "preamp project" with ciaran and myself. not quite sure when it's going to get done though due to my schedule.

[traktop]

rocket88 wrote

To get the tonestack closer to the real thing you can change the following parts:

bass2-bass1: 10nF resistor to ground 27k
treble2-trebl1: 330pF
68nF cap going into D of Q2 should be 47nF

Thanks Zach.
I will shocket caps and resistors and see what I get.
When you say closer to the real thing, you´re talking about the amp, not the pedal schematics, right?

rocket88 wrote

that's just on a quick look over. but i can also tell you there's no drive pot, it's actually a switch a rotary switch

You mean the citrus graphic, right?Taking a look to the green citrus schematics, I see a 1M pot just before Q2 which sets the gain of the effect. In fact, Johnk modded the layout downgrading the 100k resistor before the pot to 47k in order to get more gain here.

[rocket88]

Yea talking about the amp when I say real deal. The amp and the pedal schematic don't really match up to be honest.

[Frank_NH]

traktop wrote

I've made 2 builds of this one and found them a little disappointing from the "huge sound " kind of expectations.  I know that some mods were made to the tone stack to make it less bass flubby, but to me ended up being like the "tube screamer amp in a box" ,(compared to the bypassed sound of my les paul), but still being muddy sounding.

I think I will try reverting the bass tonestack cap to the original, (4n7 to 22n I think...), and radically downgrade the Q1 source to ground 47uf cap, (as Frank NH suggested on the thread), as I found this one being  a major culprit on turning this build muddy.

What are your thoughts on this build in general?
Anyway, any suggestion for an orange/matamp kind of build?

I remember johnk talking on the green citrus thread about an "Orange Citrus" build he made which had the tonestack before the gain section. I guess it is the "Citrus Graphic MKII " what he was talking about, right?
Cheers, Gilberto.

I would recommend this up on a breadboard so you can play around with the design at will.  I still believe the best way to tighten up the bass and get more focused mids is to remove (or reduce in value) the bypass capacitors from the early FET stages.  You can also try to vary the gain from each stage by modifying the source resistors and determining the appropriate drain resistors for correct bias.  It all depends on your sonic goals.

[traktop]

Frank_NH wrote

 I still believe the best way to tighten up the bass and get more focused mids is to remove (or reduce in value) the bypass capacitors from the early FET stages.

Right. Removing bypass capacitor on Q1 made this pedal lose dimension, so I think better downgrading there. Will try Q2 as well and see how it goes, (I´m on it right now).

[cylens]

I love this circuit and have been using it for a while

I am using a 6 way rotary switch with caps ranging from 68nF (original) to 150 pF at the earliest stage
this + a way of blending the original signal (to preserve transients) and it's amazing...

I am not using the boost control and replaced the 1k pot/1k5 combo by a 604 ohms resistor

[Frank_NH]

I did a quick hand calc this morning, and using 220 nF and 470 nF source bypass caps rather than 22 uF and 47 uF will accentuate frequencies above the 150 Hz range.   That should reduce your low end flubbiness without losing some of the useful guitar low end and mids.

[traktop]

cylens wrote

I love this circuit and have been using it for a while

I am using a 6 way rotary switch with caps ranging from 68nF (original) to 150 pF

Forgot to shocket that one...
What value did you find yourself using more?

[traktop]

Frank_NH wrote

using 220 nF and 470 nF source bypass caps rather than 22 uF and 47 uF will accentuate frequencies above the 150 Hz range.   That should reduce your low end flubbiness without losing some of the useful guitar low end and mids.

Thanks for taking you time ;)
I´ve been trying replacing both Q1/Q2 source bypass caps with 1uf while keeping the original 22nf bass cap with good results.
When you say 220nf/470nf rather 22uf/47uf you mean Q1/Q2 or Q1/Q3, (as the only source bypass 22uf cap is the Q3 one).

[Frank_NH]

Well, I speaking in general terms for the fet stages.  I would try this cap replacement on Q1 and Q2 first and see how you like it.

[traktop]

Ahh, get it, Thanks.

[cylens]

traktop wrote

Forgot to shocket that one...
What value did you find yourself using more?

it really depends on the instrument (bass or guitar), pickup configuration, amp and blend setting, and overall gain...

look at this video a friend of mine has made, the "FAC" control is the rotary switch, you'll clearly hear for yourself:

https://www.youtube.com/watch?v=pRcceH9rwps

[traktop]

So cool!!!
What did you use for the blend circuit? (recently tried a green bigmuff with a blender for our bassist but didn´t like the results).
Finally I think I will keep the original schematics tone-stack and and 2x470n source bypass caps for Q1/Q2, (confirm soon)

[cylens]

I've used the splitter portion of the runoffgroove splitter-blend and the ggg mini mixer. here's my layout for it:



there's just a 100k log pot in one of the loop for the dry level control

[rocket88]

sounds pretty bad ass cyclens, i'm actually impressed with the pedal now with those changes. btw, i you know that i've been toying with blends for several builds, but the one think i really want to be able to do is boost the dry signal. it sounded like this does that, am i right?

[Silver Blues]

Rocket, have you seen the blend scheme from this?:



Seems to me that would do what you want here, and it's been touted as a great blend. You could make it standalone by using a single TL072 for the blend and output buffers.

[cylens]

rocket88 wrote

sounds pretty bad ass cyclens, i'm actually impressed with the pedal now with those changes. btw, i you know that i've been toying with blends for several builds, but the one think i really want to be able to do is boost the dry signal. it sounded like this does that, am i right?

the ggg mixer has a resistor that you can tweak to privide boost. on this particular build the gain is set to unity but, you just have to swap a 10k resistor (or more) in place of a 100k one to have a boost. on my layout it's the 100k resistor going from pin 9 of the TL074 to the bottom line.

I've had a few PCBs made for the green citrus, but they're all gone. I'm working on a new version, including the blend and the switchable caps (and also a switch for the low pass filter stages just before the output)

[rocket88]

silver - i have and i think i asked about that clean control before, and if i remember correctly i was basically told its the same as a buffered blend, so i kinda just left it alone. if that was wrong then i may give it a try.

cylens - that's good to hear, so i may have a deeper look at using it in some other builds.

really what started my thinking about having a clean control that actually boosts the clean and leaves the output of the effect alone is doing something similar to what traktop mentioned of using it with a big muff, and changing the way i do my modded rat. my one issue with the typical buffer blends we've come to use it that it cuts the signal of the effect, which i want to avoid. so much nicer being able to just add clean to you effected signal and not have to play around with lowering the effected signal, know what i mean?

[cylens]

yup, it's all about ergonomy. i'm a sound engineer myself, so the "mixing desk" paradigm is much more appropriate to me. ideally I would want a clean control, a dirt control, and a master control :D