Like a Phoenix....

[duhvoodooman]

Sometimes it seems to take a long time for an obvious idea to pop into my thick skull! A little while back, I made THIS POSTING to explain the differences between my original Zonkin' Yellow Screamer overdrive pedal and the newer BYOC Overdrive 2. The ZYS has developed quite a following around here, but various circumstances have conspired to make it very expensive for me to make and sell. But people keep asking about it, so I wanted to tee up the new Overdrive 2 as a more cost-effective alternative.

Then it finally hit me--why does it have to be one or the other?? Why not take the Overdrive 2 design with its cool new features, add a few more, and come up with an even better version of the ZYS?? One that will outdo the original. And from that long-overdue brainstorm (and with a little encouragement from our friendly site admin Robert) comes....the Zonkin' Yellow Screamer Mark II, arising reborn, like a phoenix from the ashes!

The ZYS Mk II starts with a MOSFET conversion-based Overdrive 2 and adds these features:

• Socketed diode connections for swapping to different clipping configurations (several provided)
• DVM's custom hybrid MOSFET conversion (best of both worlds!)
• Your choice of MPSA18 BJT or BS170 MOSFET boost
• Two additional opamps (total of five!)
• NEW toggle switch mod to allow placing the boost stage before or after the overdrive stage (very useful!)
• That snazzy ZYS yellow paint job & red graphics!

But make no mistake--it's still based on the same TS808 vintage circuit as the original ZYS, and has the same killer tone. The best part is that, even with all these added features, the price is way below the $250 I was quoting for the original ZYS. Yours for $165 + shipping. So who wants serial number 1??

Here's what ZYS Mk II looks like:

BTW, I'll continue to offer the straight TS808-based version of the OD2 ($135) and the basic MOSFET conversion ($145), as well. These prices are for a fully assembled, tested, painted & decaled pedal; shipping is extra. Prices subject to change, just like the rest of the world....

 

[sumitomo]

Your building up some serious GAS Vood.Sumi

 

[duhvoodooman]

ZYS Mark II serial number 1 is SOLD!! :AOK: :dude: :beer:

You still have a shot at #2, though! oke:

 

[Algonquin]

I love the boost feature you've incorporated into the pedal DVM. :AOK:
My gear fund is tapped out (so I've been told :nono: ) for the immediate future, but this looks like a pedal I'd be interested in.
Looking forward to seeing pics of the first pedal to go out! Congrats to the Fretter who scored #1. :bravo:
Cheers :beer:
David

 

[duhvoodooman]

I love the boost feature you've incorporated into the pedal DVM.

Yep, it's a great addition to an already great pedal, but I really can't take any credit for that one! The boost was added to the overdrive as part of BYOC's redesign of the original Overdrive kit. This was one of several enhancements made to the old design; the new Overdrive 2 version came out this past January. So Keith Vonderhulls should get all the kudos for that one....

 

[duhvoodooman]

Had to order two octave fuzz kits (thanks to Robert's Octafuzzy video!), so I picked up an extra OD 2 kit "on speculation" to qualify for free shipping. So whoever buys the next OD2-based pedal gets my customary $5 free shipping discount:

TS808-based stock build: $130
MOS conversion build: $140
ZYS Mark II, S/N 002: $160​

 

[duhvoodooman]

ZYS Mark II S/N 001 pix:

 

[sunvalleylaw]

Looks sweet!

 

[tot_Ou_tard]

Can you explain the custom hybrid MOSFET conversion, Vood?

 

[duhvoodooman]

Can you explain the custom hybrid MOSFET conversion, Vood?

Sure. The stock OD2 kit uses no MOSFET componentry, per the original TS808 design--just bipolar junction transistors (BJTs). The boost circuit in the stock kit is BJT based, as well--basically the same circuit design as the vintage Electro Harmonix Linear Power Booster.

The "MOSFET Conversion Kit" that BYOC sells as an $8 add-on contains the components needed to convert the OD2's circuits in 5 locations:

• Input buffer
• Output buffer
• Opamp
• Clipping stage
• Boost

But you don't have to do the full MOSFET conversion. I prefer to use only some of the five, hence my use of the term "custom hybrid MOSFET conversion". I like the MOSFET input buffer for it's higher input impedance, which preserves a bit more top-end and minimizes any "tone-sucking". And I like the MOSFETs used as clippers in the clipping stage--a nice warm, meaty tone that's a bit fuller and smoother than the stock TS808 silicon diode clipping. MOSFET clipping has become all the rage in a number of well-known boutique overdrives, for good reason.

The MOSFET-based opamp, a CA3260, can be swapped in & out of the circuit as you desire, because the kit uses an opamp socket. Personally, I like both the stock TS808 JRC4558D and the hifi Burr Brown OPA2134 opamps a bit better, but these are very subtle differences anyway.

However, I prefer the stock BJT's in the boost circuit and the output buffer because they have more drive than the MOSFETs do. I really see no benefit to the MOSFET output buffer, and MOSFET buffers are also a bit noisier than the BJT versions. And the BFT-based boost sounds just great to my ear, and still very clean unless cranked way, way up, plus it has a much better defined bottom end. If you really want maximum top-end jangle, the MOSFET boost might be preferable, but I find the BJT version to have plenty of top-end detail. IMO, the better bass response and stronger output characteristics of the BJT trump any small advantage the MOSFET may hold in treble response.

Prolly more detail than you wanted, Tot, but you know how I am once I get going....

 

[piebaldpython]

Tot.....I have the OD2 exactly as DVM described with the only difference being that I have the MOSFET boost.

It's a great pedal, lots of tonal options, esp with the MOS in the clipping stage. Lots of sounds to explore.

 

[tot_Ou_tard]

Sure.
Prolly more detail than you wanted, Tot, but you know how I am once I get going....

Nope, that's exactly the kind of info I wanted. Thanks!

 

[duhvoodooman]

ZYS Mark II Serial No. 002

I currently have the build of ZYS Mark II S/N 002 underway--this one I'm building "on spec", so will be looking for a good home for it. But there's more to the story for this one....

Robert & I have conspired a bit, and when the pedal is fully assembled, it'll be taking the "Alberta Express" out to Camrose, where Robert has agreed to feature it in one of his video demos! Now you guys can hear the ZYS MkII played by a truly competent axe-man, rather than having to extrapolate its capabilities by listening to more of my aimless wanking. I'm really looking forward to that video!

Once Robert is through with the video, he'll be returning the pedal to me, at which time it'll be up for sale ($160 + shipping). Heck, it's up for sale now, if anybody want to reserve it. Here's your chance to own a great overdrive-boost pedal that's also gonna be a movie star! :rockon:

 

[Robert]

How much does the value go down after I'm done soiling it with my filthy blues-jazz **** attempts and bulls**** noodling?

 

[duhvoodooman]

How much does the value go down after I'm done soiling it with my filthy blues-jazz **** attempts and bulls**** noodling?

Good point.

Price dropped to $14.99.

....ONLY KIDDING!! :rotflmao:

BTW, I wonder if that ***hole will comment on the video? I think he's got it in for you, RR! Prolly just jealous....

 

[marnold]

As long as it doesn't suffer any vein-related damage.







Wait a minute, that sounded absolutely awful.

 

[sunvalleylaw]

HERE is the thread I was looking for. I have one of these coming!! Very excited. I love the strat graphic on the side too! :happy

 

[duhvoodooman]

Just a note to any late-comers to this thread--the pricing mentioned in the first post is no longer accurate. For current pricing on this and my other pedal offerings, look HERE.

 

[sunvalleylaw]

Mine is here!!!! I had a very busy day, and though it arrived with the mid day mail, I did not get to open it until around 6 when I finished my last appointment today. It came packed very, very well, with the spare op amps, diodes, and other parts all separated and packed nicely.

I plugged it into the Fender Concert at work, and it sounds just great! I had my Bad Monkey there too, and by comparison, the ZYS just sounds . . . tighter? In fairness, the BM was set for warm rhythm, but in the very limited time I had to mess around with it, I sure like the ZYS! The boost, which DVM set up as a MOSFET, that can be converted to the standard linear boost, sounds tremendously clean.

Tonight the Oscars are being watched in the guitar room, so I can't hook it up to the Peavey and play more yet, but I look forward to really tearing into this thing. Thanks DVM!

 

[Monkus]

Im sure you'll love it, I have a hard time weighing the merits of using the OD's on the line 6 M9 and just sticking the ZYS in the chain. There's a warmth in the ZYs thats hard to emulate, its just well...different. I got #003 !

 

[Tig]

Im sure you'll love it, I have a hard time weighing the merits of using the OD's on the line 6 M9 and just sticking the ZYS in the chain. There's a warmth in the ZYs thats hard to emulate, its just well...different. I got #003 !

When/if I get an M9 or M13, I'll still use my BYOC OD2 and Mouse. I don't think you can beat a well made pedal like that.
From the reviews ("not warm", "not organic enough"), the distortion and OD models on the M9 are it's only weak area.

 

[sunvalleylaw]

When I do look more seriously at the Line 6 M products, I am inclined to look at the M13, partly because of an "effects loop" where you can have a ZYS and a Rodent, and maybe your favorite Fuzz or whatever, and they can be set up to be ahead or behind other effects you use in the M13, and that position can switch depending on what "scene" you are using. That is the way I understand it anyway.

 

[sunvalleylaw]

Hey Vood! I have a question. I feel I am getting to know a lot about the TS9 side of this pedal, but am still learning about the boost. (which I love BTW). I hear a lot of people raving about the Xotic RC Booster and how great it is. I am just curious, how does this boost compare technically, etc., if you can say? The boost in the ZYS seems great to me, but I was just curious.

 

[Robert]

I have both, and the RC Booster is very, very transparent, and it has bass and treble and gain knobs. It's like a very transparent low gain pedal with great tone. It is really fantastic. The ZYS boost doesn't provide the same kind of sparkle to the tone, although it does the job fine for boosting volume.

 

[Eric]

Well, this is something I never got. Why does anybody give a second thought to a boost? Isn't it just something to raise the voltage of an unamplified signal? I mean, you have this RC booster, many built-in boosts on amps (I have one on two of my amps), stuff like the MXR microamp, and built-in pedal circuits like on the ZYS and (I think) FT Fulldrive.

So Robert, you're telling me there is a difference? Other than it just being an additional gain stage with a passive EQ built in? How exactly does it differ?

I just never understood the whole idea. I figured a boost is a boost is a boost. Seems like a simple circuit to me, so it didn't seem like there could be much variation from one pedal to another.

Disclaimer: not trying to ruffle any feathers here -- just trying to understand a little better.

 

[Robert]

Yes, there is a difference. Exactly how isn't so easy to explain. I am not a tech guy. The RC Booster adds to your tone in a way that is very pleasant. Eric, the way for you to find out, is to try. You want to understand, which mean you will need to try a few different boost pedals as well as the RC Booster. Words do not portray the difference adequately enough.

 

[Eric]

Yes, there is a difference. Exactly how isn't so easy to explain. I am not a tech guy. The RC Booster adds to your tone in a way that is very pleasant. Eric, the way for you to find out, is to try. Words do not portray the difference adequately enough.

Hmm. OK, point taken. Want to loan me yours??? oke

 

[duhvoodooman]

Interestingly, the RC Booster isn't a boost in the classic sense at all--it's a modification of the Tube Screamer circuit! Here's a description I came across in the TDPRI forum from a guy who obviously knew what he was talking about, describing the AC and RC Boosters:

"They are both TS variants, with the main difference being an active EQ (Baxandall) bootstrapped off of the recovery (second) gain stage.

The AC and RC are basically monozygotic, with only a few differences:

-AC has one extra cap in the tone circuit
-RC has more interstage attenuation at two points in the circuit
-RC has a 250K drive pot instead of trad. 500K TS value in the AC
-AC has asymmetrical diode clipping setup identical to Boss SD-1
-RC has 3 1N14148 diodes X2 for greatly reduced clipping​

They are really cool designs, but I'm not clear as to why they were monikered as boosts/preamps. Maybe a fear of being branded as just another TS variant, but I think it's of little consequence. I love the RC's light drive capabilities, and have been waiting for someone to package a TS variant with a circuit like that (maybe minus the active EQ)."​

BTW, "monozygotic" just means they're both based on exactly the same circuit (literally, "one egg"). They just differ in a handful of the components, with a key one being that the the RC's clipping stage (BTW, "real" boosts don't have clipping stages!) uses two oppositely oriented sets of three 1N914 silicon diodes in series. This has the effect of tripling the forward voltage threshold, so a lot less of the signal is clipped, resulting in a much cleaner sound than a pair of 1N914's (the stock TS clipping) gives. The RC has less gain than the AC, and both have separate treble & bass controls vs. the classic TS's single treble-cut control.

From what I've read, I would think that the RC Booster might sound quite similar to the ZYS's overdrive stage with the clipping switch in the middle "lift" position, and the gain pot down in the first half of its sweep range. The ZYS boost stage is a true boost, essentially identical to the classic Electro Harmonix Linear Power Boost circuit. That's just a simple single bipolar junction transistor (BJT) boost--a much, much simpler circuit than these two Xotic pedals. Not at all surprising that it sounds much different than the RC Booster.

For those of you who can read a schematic and may have some knowledge of the classic TS design, check out the AC Booster schematic, following. Looks pretty familiar, eh? BJT input and output buffers, and a dual opamp with a clipping circuit in the feedback loop of the first opamp stage, and tone and volume control on the second opamp stage! The tone control section is significantly different than a typical TS pedal, but otherwise, its Tube Screamer ancestry is very clear:

Here's a TS-808 circuit for comparison, compliments of effects guru Jack Orman. The similarities should be evident even to an electronics novice. Sure, there are many individual component differences, but look at the overall layout of the circuit:

 

[sunvalleylaw]

LOL! Thanks for the technical data Vood! That'll answer it! Seriously, it does help to have the techie info along with some explanation/translation. I do think the ZYS is a cleaner TS than my Bad Monkey, and I tend to run it in the bottom half of the gain settings most of the time. I have not run it in the "lift" mode much, and for some reason (initial ear response probably) put have it over at setting 2 (toggle to the right) and have mostly left it there. I may go moving things around now just for fun.

For my purposes in boosting, I personally like the one in my ZYS very much. I typically set up the drive side for the sound I want, then kick on the boost for volume without adding gain (ie, I have the switch set so the boost comes on after the gain stage, rather than before). But once in a while, I will mess around with that too, so I can hear what it sounds like running the boost into the gain stage when I turn the boost on, rather than amplifying the gain stage after the fact.

 

[Ch0jin]

.......

.....The AC and RC are basically monozygotic, with only a few differences:

​

Firstly, excellent reposting of an explanation that uses the word "monozygotic"! I've never used that word before, but I'm going to try to work it into conversation today.

.......
.......The similarities should be evident even to an electronics novice.......

That made me lol So you're saying that if you have no idea what the symbols mean, you can still have some fun playing "spot the difference" with the pretty pictures

It just made me think of games night at DVM's house. "C'mon kids, you've got 60 seconds to spot the component changes from the ZYS to ZYS MkII using only a mobile phone camera image of the PCB. Your time starts.......NOW!"​