What's the best Transparent Distortion pedal?

[musicalmartin]

I like my CT0-1.........nuff said.

 

[cbtd]

To throw something else in the mix, there is the MHP RAW pedal which is a preamp with multiple gain stages and no clipping diodes. It has a really broad tonal range that one could argue is "transparent" (not sure I know what to make of that word, so many different definitions). 11G could speak best to that one.

 

[Gnobuddy]

I don't own one because of the exorbitant asking price, but this one (CE pedals Fet Dream) has caught my ear: http://cepedals.com/products.html

Here is a sample of what this sounds like - you can still hear the guitar and amp tone through it:


11 Gauge, if you have any info on the FET Dream's schematic, I'd love to know anything you can share. I don't much like the idea of shelling out $230 for what is probably about $23 worth of parts in a nicely painted box.

FYI, All Electronics (Allelectronics.com) is blowing out a small-signal P-channel JFET at ridiculously low prices: http://www.allelectronics.com/make-a-store/item/J176/P-CHANNEL-J-FET-TO-92/1.html

This JFET seems to have been designed as a switch rather than for small-signal amplifier duty (a distortion pedal is an amplifier of sorts). Because of this it "wants" to draw considerably more current than a JFET designed as a linear amplifier. But from the datasheets it looks like it can be biased down to maybe 4 mA drain current without too much trouble, and that's low enough to probably make a viable distortion stomp-box.

Given the twenty-cent price, a few of these might be a good foundation for a FET-based distortion pedal for those willing to experiment - and willing to deal with a positive-ground pedal!

To the OP's request I'm also going to suggest an amp emulator pedal (just as 11 Gauge predicted). Take a listen to these two video clips, maybe one of these $40 pedals (there are also 2 more amp sim pedals in the lineup) will do what you want:

Joyo "American Sound":


Joyo "AC Tone":


I just bought both of these pedals. I haven't had them long enough to have a final opinion, but initial impressions are that the sound is surprisingly good - and that both pedals do seem designed to feed a line-level input on a mixer or P.A. rather than a guitar amp input.

Both pedals get unacceptably noisy if you turn the gain all the way up and plug the output into a guitar amp input. Also you need to turn the output level down to almost zero to make this work. Both these things are symptoms of too much output voltage for a guitar amp input - plugging into a guitar amp input isn't the right way to use these, IMO.

But even into an amp input, they're acceptable at lower gain settings, and should be fine feeding an FX Return input on a guitar amp. Unfortunately my Princeton Reverb doesn't have an FX loop, so I can't try that particular idea out.

I haven't opened up either pedal yet, but the surprisingly high amout of hiss (and rumbling low-frequency 1/f noise) from these two Joyo's at full gain makes me suspect they too contain one or more CMOS logic inverters used as linear amps, as 11 Gauge described in one of his posts. I myself tried that trick (CMOS logic inverters used as linear amps) in the 1980's and 90's and they were always very "hissy". Not surprising, as those devices were never designed to perform in this way, with small analog voltages.

-Gnobuddy

 

[StoogeSurfer]

Fulltone Fat Boost 2 or 3 can get what I think you want. They don't lop the top and bottom off like a typical clipping distortion pedal.

 

[Gnobuddy]

The Suhr Riot is NOT a Transparent OD - is a full-on Drive pedal.

However, if you are into this pedal then again, much has been spoken of the copy of this - the JOYO British Sound.

I just got one of these, and IIRC it doesn't sound like the usual "amp with clipping diodes" harsh overdrive to me. At low gain settings there is a rather subtle and progressive distortion, unlike most overdrive pedals which seem to go straight from silent to full-on buzzy racket. To my ears the timbre of this pedal is also sweeter than Tube Screamers and Muffs and whatnot - it sounds a little more "tubey".

Elsewhere on the 'Net I read that this series of pedals are based on the Tech 21 "Sansamp" products. Those use MOSFET's (in a CMOS op-amp) rather than clipping diodes like most overdrive pedals.

The "American Sound" from the same family seems to have the subtlest and most progressive overdrive of this family of pedals. I posted a link to a demo vid earlier, so I won't repeat that here.

-Gnobuddy

 

[Stratburst]

Swap out 'transparent' for 'versatile' and my pick would be the Digitech Hardwire SC-2. It's one of the few distortions that sounds good with the gain barely on and it kicks out a solid amount of gain. It's a little mid-scooped but the 2-band EQ gives it a lot of flexibility.

A real bang-for-buck winner, IMO.

 

[hiero]

Timmy doesn't = Transparent
Timmy = lots of treble added, as does most "transparent" pedals..

I was trying to use the term "neutrally Eq'd" but i'm not even sure that's truly the case. If something was transparent, then it wouldn't need a tone knob. Or 2.

Sorry this is my current "thing that bugs me" possibly worse than the JRC4558D mojo thing...

to make up for going off on one, guys in the US watch this.

(link removed)

Awesome film

Ah - what you probably want is a good Compression Pedal then...

 

[artdecade]

Thanks for all the info on the Angry Troll, 11G. Your knowledge about this stuff is second to none!

 

[11 Gauge]

I just got one of these, and IIRC it doesn't sound like the usual "amp with clipping diodes" harsh overdrive to me.

That's why I said that the clipping diodes must be selected and tested carefully - that is one of the most evident tweaks to the Guv'nor'ish foundation. Compare it side-by-side with a Crunch Box which uses the same LED clipping pair as the Guv'nor, and it should be pretty clear.

Basically speaking, the "threshold" or "proximity to clip" with shunted diodes to ground determines a lot of these characteristics. I should also add that the Riot has a unity gain recovery stage that can help to make things sound a little more dynamic, bouncy, or whatever term you are comfortable with.

I just wanted to highlight the usual caveat with using the Guv'nor as a distortion pedal's foundation.

Even though it's not a distortion pedal, the OCD is another decent example of how to circumvent the issue with shunted clippers to ground - it has a recovery gain stage after the clipping diodes. There is sufficient gain that it makes the cleanup with the volume knob very good in a way that some folks consider to be amp-like for this reason.

It's not impossible to get these tones with op amps and clipping diodes, as you've witnessed. It's just that IMO it's probably a harder way to implement it, or there's just diminishing returns in many instances.

Elsewhere on the 'Net I read that this series of pedals are based on the Tech 21 "Sansamp" products. Those use MOSFET's (in a CMOS op-amp) rather than clipping diodes like most overdrive pedals.

AFAIK, Tech 21 continues to use "ordinary" op amps in everything. The older stuff used TL072/74 chips, which are just basic jFET-input op amps. Some of the newer character series stuff might be using common bipolar-input op amps like the JRC4580, but I don't recall it being an actual mosFET-input op amp. That is an uncommon chip, and I've only heard of it being used in a few pedals, like the BJFE Honey Bee.

A CMOS chip isn't an op amp - it's a logic "inverter" chip. They are kind of hard to design circuits around, because the unbuffered type must be used, and the impedances of each inverter are "horrible WRT audio designs." The inverters will actually load each other down, and it's not uncommon to see pedals that use an inverter to have in and out transistor or op amp buffering to "fix" the impedance issues. Inverter chips also make it hard to implement "standard" tone circuits because of this loading effect.

 

[11 Gauge]

Thanks for all the info on the Angry Troll, 11G. Your knowledge about this stuff is second to none!

No prob. I'm just glad I could still recall what the deal was with that one. I think Tripps posted clarification on other discussion sites back in '09 or some time around then?

But I always liked the idea of the Tone Leper, even though I personally have no use for it. So when Tripps clarified that the AT was more than just a tweaked TL, it kind of stuck in my mind.

It's kind of funny that I really like how Tripps does stuff, but I have no WHE pedals of my own. But I do have a few of the newer MXR's, and I've implemented some of the stuff that he's responsible for with the newer Fuzz Face pedals.

The guy is really good at what he does, and it's even evidenced in something with a rather simple circuit like the Angry Troll. Another instance of something being more than the sum of its parts, IMO.

 

[Gnobuddy]

AFAIK, Tech 21 continues to use "ordinary" op amps in everything. The older stuff used TL072/74 chips, which are just basic jFET-input op amps. Some of the newer character series stuff might be using common bipolar-input op amps like the JRC4580, but I don't recall it being an actual mosFET-input op amp. That is an uncommon chip, and I've only heard of it being used in a few pedals, like the BJFE Honey Bee.

11 Gauge, from what I read the Sansamp uses TLC 272 opamps, which I believe are entirely CMOS - Texas Instruments calls it "LinCMOS technology".

I saw some supposed schematics of the Sansamp floating around the 'Net using TLOxx op amps, but I also read that people who built them that way didn't get them to sound right; apparently the TLC 272 is a vital part of the sound.

I don't know any of this first-hand, only what I've read on the 'Net, so of course it could be wrong. Have you personally taken apart one of the Sansamps and found nothing but TLOxx opamps inside?

A CMOS chip isn't an op amp - it's a logic "inverter" chip.

There are CMOS op amps (like the TLC 272), and of course there are those CMOS 4069 and similar hex inverter logic chips.

I built an entire drum machine around a hex inverter in the 1980's. Four of the inverters were biased to linear operation and each one used in a tuned-T ringing oscillator to simulate a drum sound. I used a 4017 decade counter driven by an oscillator (made from the remaining two inverters) to generate 6 or 8 sequential outputs, which drove the ringing oscillators through DIP switches which you used to select which beats triggered which drum sound.

IIRC I also had a monostable multivibrator in front of each tuned T "drum", to get a single clean trigger signal out of the slow pulses from the 4017.

Put together you had a drum machine which could do 3/4 and 4/4 time signatures and rhythms composed of up to four different 8th-note drum sounds of your choice. It was monotonous and crude, but it worked, and it was my first drum machine.

I also tried using one of those hex inverters as an audio preamp stage, and it hissed like crazy. Just like my two new Joyo pedals do at full gain.

-Gnobuddy

 

[11 Gauge]

I don't know any of this first-hand, only what I've read on the 'Net, so of course it could be wrong. Have you personally taken apart one of the Sansamps and found nothing but TLOxx opamps inside?

If someone's taken a character-series one apart and found a certain type of chip, I don't doubt that is what's in there. It's been awhile since I've seen the guts of one of those, and the SMT stuff requires that you pay attention a little closer.

I DO have a GT-2 in my possession, and it has a TL072 and TL062 for at least two of the four op amps. IIRC, the '072 is for the first pair of gain stages, with one being for the Fender-type sounds, and the other for the Marshall/Boogie-type sounds. And IIRC, the TL062 is for the active EQ stuff, which is a Baxandall and some other tone shaping, probably for the "mic placement" circuitry.

...So that leaves two other dual op amps that I swore were TL072's, but it does look like at some point other op amps were subbed in, unless they were used for "IC2" and "IC3" all along, and I just wasn't paying attention (I haven't had my GT-2 apart in a long time).

(not my GT-2 in that image, not that you can make out the chips anyway).

Here's a schematic from a Classic that was traced 11 years ago, and no mention of anything other than a '072 and '074 in that one, either:

But it does appear that the Blonde uses TLC2262 and TLC2264 chips. Sho'nuff, they are 100% mosFET-based op amps. IIRC, all of the character series are built off the same interchangeable pcb (or at least some within the series).

This makes me want to take apart my GT-2 and double check IC2 and IC3. Mine's fairly old though (mid to late-90's), so subsequent revisions may have had the op amp substitutions.

Thanks for the heads-up on that. It's the kind of detail that I'll miss time and time again with SMT circuit pedals.

 

[tekbow]

Ah - what you probably want is a good Compression Pedal then...

Nah.. not a fan of compressors, my issue is a purely academic one, and a bit of a rant against hype in general. I'm not angry because ODs and Dists don't deliver on their promise, I'm a huge fan of them and the tonal variety they intoduce, even the one's that are neutral and give you "more" of what your amps got. I especially like fuzz.

I think i just had a mad minute were i got worked up about how terms like this get invented by fanboys, then get taken up by wannabes, then enter the general conciousness as a buzzword and people have a total misconception about what it means.

I also hate mangement speak, i think this is the root of my hatred of hype.

Used to have a manager, who would drivel out rubbish like "blue sky thinking", "helicopter view" "actionables" and my personal favourite, which in fact as entered mainstream conciousness as a perfectly acceptable word, "Proactive". mainly because it was used non stop..

 

[11 Gauge]

apparently the TLC 272 is a vital part of the sound.

I found this regarding the PSA-1. It's a fairly detailed discussion:

http://www.groupdiy.com/index.php?topic=40781.0

Apparently, there is some sort of "foundation" that is used for many/most of the SansAmp products, and even with the older PSA-1, "special op amps" was starting to be marketed as necessary for a proper amp-like characteristic.

What is interesting is that some of the chips in the PSA-1 in that discussion had their brandings removed. So that alone doesn't confirm that mosFET-type TLC-series chips were used, but it doesn't rule it out, either.

I can also say that the "slew rate thing" was mentioned as being an important facet. A TL072 has a slew rate of about 17V/uS, and the TL2262 has a slew rate of ONLY .55V/uS, so that could be rather important for a non-diode clipper-bound distortion circuit.

And the TLC2262 is also cheap enough (especially in bulk) not to exclude it from using in a mass produced pedal. It's about 3X the cost in non-mass numbers, so it might even be a moot point when purchased in bulk (~80 cents/2500 units) versus the TL072 (~30 cents/2500 units).

If the Tech 21 buggers don't have good overvoltage protection, applying 18VDC might determine if they are indeed TLC's, because they top out at 16VDC power handling. Not that I suggest doing that...

But at least with the PSA, it looks like it's standard thru-hole and not SMT. So the chips could be swapped to hear if there's any substance to the TLC chip thing.

 

[blowtorch]

I also hate mangement speak, i think this is the root of my hatred of hype.

Used to have a manager, who would drivel out rubbish like "blue sky thinking", "helicopter view" "actionables" and my personal favourite, which in fact as entered mainstream conciousness as a perfectly acceptable word, "Proactive". mainly because it was used non stop..

ha! gotta love that new "going forward" and "reaching out" crap.

 

[david henman]

...i'm still infatuated with a jetter gain stage red that i literally stumbled upon.

i know, i know, that will change, but for now it inspires.

 

[tekbow]

ha! gotta love that new "going forward" and "reaching out" crap.

He stopped using it with me after i made a point, for 3 months, every single time terms like that were used, of saying things like:

"Proactive? you mean being prepared in advance?"
"Actionables? you mean stuff that needs doing now?"
"Blue Sky Thinking? You mean in the best case?"
"Helicopter view? Are you seriously expecting me to buy this crap? it doesn't make you any better at your job you know"

 

[11 Gauge]

I also hate mangement speak, i think this is the root of my hatred of hype.

Used to have a manager, who would drivel out rubbish like "blue sky thinking", "helicopter view" "actionables" and my personal favourite, which in fact as entered mainstream conciousness as a perfectly acceptable word, "Proactive". mainly because it was used non stop..

Yeah, any kind of "empty content lingo" is annoying.

Or anything that would prompt me to tell someone that "they exhibit a tenacious grasp of the obvious."

I recall the corporate lingo nonsense the most when it comes to the resume, and someone forwarded me with the top 50 most worn-out catch phrases for "good worker attributes." The one I can't stand and was near the top of the list was, "thinks outside the box."

I realize we need these surrogate terms and phrases simply to communicate, but boy - many of them do indeed simply suck...IMO.

 

[Ash Telecaster]

I don't mean to be difficult but obviously anything that alters the tone to the extent that distortion or overdrive do can't really be "transparent." Otherwise you would here no difference in the sound.

But before you call be a butt head let me say I understand what you mean.

I have a number of overdrives and distortions and am always comparing them by virtue of playing around with them. Of them my OCD drive gives me the greatest "sense" of transparency. Obviously if you put it on a spectrum analyser you would see an enormous difference in the wave form but to my ears I hear more, I don't know...string, through the sound. Like there is a clean signal lightly mixed with the overdriven signal.

I realize the OCD is an overdrve but it really crosses into distortion territory when you crank it.

 

[blowtorch]

"to my ears I hear more, I don't know...string, through the sound."

That is exactly what I hear through my J&H old silver version, on the Jekyll side, with the gain all the way down and the level maxed. Or maybe it's ideally what I think string should sound like