MATRIXSYNTH: BLUE ZTVCO DRY DEMO & Surrounding Controversy

Tuesday, January 03, 2012

BLUE ZTVCO DRY DEMO & Surrounding Controversy

YouTube Uploaded by bluelantern320 on Jan 3, 2012

Update 10/4/2013: I heard from Ian Fritz and the controversy is over. Blue Lantern no longer offers the ZTVCO. That said, BL posts will resume.

This one, which seems to be a reoccurring theme with Blue Lantern, comes with a good dose of controversy. You might recall from a few years ago BL got into a bit of heat selling MIDIBox SIDs on eBay. MIDIBox explicitly forbids the commercial resale of MIDIBox SIDs. Blue Lantern stopped and went into producing affordable eurorack based modules and systems.

This latest controversy surrounds the source of design for the new BLUE ZTVCO. You might recall from the comments in this previous post, the design of that prototype module appeared to be a copy of Ian Fritz's Teezer (TZFM Saw VCO debuted Sep'08) design. Ian Fritz's modules are available via The Bride Chamber and Elby Designs.

In short:

1. Is the BLUE ZTVCO based on Ian Fritz's design?
2. If so, to what extent?
3. If so, is it legal?
4. If so, is it fair and does it matter?

The answer to 1 and 2 will not be known until someone gets a hand on the ZTVCO and reverse engineers it. I asked BL if he would be willing to provide the schematics to put the issue to rest and he replied no. He said people can reverse engineer it when it it's available and he is sure someone will. The answer to 3 is quite possibly so. There is currently a good thread on the subject on the forum here. The answer to 4 depends on you. My personal opinion is that it is not fair and it definitely does matter. Whether legal or not, I view it as stealing. These designs do not come out of thin air. They take time and talent and sometimes years to produce. You will see some insight on this in regards to Ian's Teezer design from him directly below. When someone makes their designs available, credit should be given.

The following is a response from Blue Lantern in regards to the claims made against him. The most important thing to read out of his points below is "3. This is not a clone, this vco is a beast in it's own cage."

via Blue Lantern on Muff's:
"I will tell you more about the Blue ZT VCO.
Here are the facts:

1. All components on the Blue ZTVCO are SMD, literally all of them.
2. The OTA used is NJM13700, modern component
3. This is not a clone, this vco is a beast in it's own cage. This has Square waves and Varible Skew waves.
4. It will retail for $295.00 each (EURO MODULE)
5. This is not a DIY project.

The $600.00 price that is mentioned was from an auction, I have no control of the out come. I started the bid at $400.00 for (2) units in one Panel. To a DIY person that is expensive, to a person that design's sound for a living it is just like buying another tool and not expensive. But who cares? is my point... I sold (1) item that I built and no longer need.

That was a DIY prototype called 'GREEN VCO'. Many suggested not to use Old hard to get parts any more. So I took that advice and started from scratch and went a whole new direction.

BLUE ZTVCO was born & is the affordable future.

It is funny how fast I am considered a threat and that I must be shut down pronto, because of the delays experienced by others. Let the quality speak for itself.

I look forward to t the new Euro-tweezer release and like mentioned above," let the users decide which is better" (and at what $$$)."

The following are some key points made from various members of the synth community including manufacturers and DIYer's from this thread on Muff's.


paults Posted: Sat Dec 31, 2011 12:56 pm [Paul Schreiber of MOTM / Synth Tech]

"I'm going to stick my nose in here just on the IP side of things, as it's a favorite topic of mine and I've been professionally involved for 25+ years in "patent wars" of all types (I have 9 patents myself).

a) a patent only gives you legal recourse in terms of copying (what is called 'infringing'). It doesn't prevent anything.

b) they run out eventually (was 17 years, now 20).

c) if there is no patent, there are other ways of protection that may or may not have legal recourse. These include trade secrets and copyrights/trademarks. Since to get a patent you have to describe something, some people elect to use trade secrets which in electronics may involve not publishing any documentation (like many synth manufacturers) or purposely making 'reverse engineering' difficult (but not impossible). Every IC made has the part number in nice block letters on the die, sandpapering off the outside ink will deter me for like 45 seconds (1 squeeze with the vise grips and a peek under the 45X stereo microscope and so much for that).

d) if a person publishes a circuit on a web page (a 'look what I did!' sort of thing) there is virtually nothing that person can do to recoup any sort of direct monetary damages. Even if you say something like "For non-commercial use only." That has no weight whatsoever so don't even bother. It's like wearing a tee shirt into a bank that says "I declare that I cannot be arrested" and then rob it.

e) so, where does that leave us? Karma. In small communities like 'modular synths' it is pretty obvious if someone copies a design without acknowledgement. Permission is another thing: who can say if it was or was not "granted" unless declared in some way (like having "used by permission of Buchla Associates" on a LPG pc board).

Now, acknowledgement/permission has nothing to offer whatsoever in a legal sense, but it can be a deciding purchasing factor and may cause unforeseen repercussions (Jurgen Haible came to me and offered all his designs because someone copied his Wasp filter without permission).

Bottom Line: if you want avoid this sort of thing, ask permission and pay a royalty. No, you don't have to. But your customers may have a certain level of expectation and hence will reward such actions so in the long run such things cost you nothing but goodwill."


krisp14u Posted: Sat Dec 31, 2011 12:57 pm []

"The difference is this is a relatively New design By Ian Frits
Who at the moment is working with Bridechaimber to bring out the Euro-format Dual Teezer

One of the last posts I have seen from Ian on the EM DIY forum is this

'One of my major projects is being ripped off as we speak. The same old tired legal arguments are being made ... he combined it with something else so it is new, etc. I've already taken down a bunch of pages from my site and may continue to do so. I seriously doubt I'll be doing much more analog synth design, if any.'

So but supporting this VCO you are killing any new designs from this well valued and respected designer

But hay you don’t give a fuck"


Luka Posted: Sat Dec 31, 2011 8:47 pm [Muff moderator]

"I am a moderator of this forum but i am expressing my opinion because i deeply value people like Ian Fritz.

People like Ian Fritz fuel the SDIY scene and they should be revered for the generosity, ingenuity and brilliance - not taken advantage of."


Muff Wiggler Posted: Sat Dec 31, 2011 10:14 pm [Muff owner]

"I totally agree with Luka here

I have no damn idea if the module is a rip off or not. And if it is, I have no idea if that's legal or not.

I've always been clear that unauthorized copyright infringement isn't accepted at this forum, and I've taken every complaint that I've received seriously.

Ian contacted me about a different Blue Lantern layout, and I stopped the sale of it through here.

I don't know if this one is different, if it's a ripoff or if it's just rude or if it's totally original. I have no idea. If Ian feels this is the same problem as before, or if it is still an unacceptable mis-use of his own work, I hope very much that he will contact me and let me know so it won't be so difficult for me to know what is right and what is wrong here.

If this sort of thing is causing designers to stop working on designs for this scene, I don't want this forum to be any part of causing that. If needed I'm prepared to re-write the forum rules so that we can prevent that here. The designers and engineers are the very reason we all have these wonderful instruments and this scene and this very forum. I will NOT let this forum contribute to pushing people away from the scene."


frijitz Posted: Sun Jan 01, 2012 2:00 pm [Ian Fritz]

"[asterisk wrote: 'so if your TZ core is a new concept (and i believe it is), did Cyndustries Zeroscillator steal your TZ core? or is that a different design? ive seen or heard no mention of your name in regards to the Zeroscillator.']

My understanding is that the ZO is a Tri core unit. I believe Cynthia got permission from the old newsletter where an early DIY design was presented, although it sounds like the final design differs significantly. But I've never seen a ZO and all I have to go on is some comments I vaguely remember from the message boards and the ZO instruction manual. I do know that Cynthia is very careful to always get appropriate permission and has even decided not to pursue designs that might be even similar to those of the designers she works with. She has told me that herself.

Quote: 'is that the only other thru zero VCO out there? or are there others?'

There are a number of Tri core designs available, including designs from Rene and JH. Unless I misunderstand, both have problems at very low frequencies, a problem I managed to lick after months of work. There is also a cool design by Henry Wamsley that is a Sin core. Also problems at low frequencies.



bridechamber Posted: Sun Jan 01, 2012 3:13 pm [bride chamber]

"Personally, BL, I would love to see the schems so we can settle this argument. The things that pisses me off most is that this was COMPLETELY AVOIDABLE with some communication.

I can personally vouch for the huge amount of time, effort, frustration, and most importantly, KNOWLEDGE AND EXPERIENCE that went into Ian's Teezer design. He's a perfectionist and has the chops to pull off a completely new approach to through-zero.

A schematic of Blue's would be the deciding factor here. There's no danger of it getting ripped off since no one can produce a VCO like that for less money. If there's nothing to hide, please show us so the drama can end.

As for the "vapor-ware" Euro Teezer we've been working on... a couple things. If you would have asked Ian a few months ago, maybe this could have all been worked out, you could have paid him royalties, and again -- no drama, awesome circuit. As it is, I have 75 very nice panels sitting on the piano, w/ matching brackets and lots of circuit boards too. Like Ian mentioned, they've been slowed by some family tragedies. You could have mentioned you were coming out with this -- that simple. It would have saved a lot of time and money, and made some very difficult days less stressful.

Our Teezer will not be as compact. It will not have any SMD parts. It will be heavier. But it will be Ian's design, money will go to Ian.

Like others have pointed out, there may be nothing we can do legally. It just hurts the community. Ian's been publishing his schematics since Electronotes in the 70s, and now he wants to stop. Why would anyone go through all that work -- creative work that comes from countless hours of studying, school and experience -- just to have it stolen? NO ONE would think it was fair if it happened to them.

And again, if it's not stolen, please post the schematics. Leave off component values if you want."


paults Posted: Sun Jan 01, 2012 3:58 pm [Paul Schreiber of MOTM / Synth Tech]

"This is similar to a situation I had to deal with.

Company X announces a filter that appears to be like an existing MOTM design. I ask the person for the schematics of their design so I can clear it up. This person was a former MOTM customer, so thay already had my schematics. I assured them I had no intention of 'stealing' their design (I like my design!), I just want to get this one thing out of the way early.

Well, I was a bit shocked when I got this over-the-top, flaming email about "No you can't have it, I'm gonna sue you if you try to publish it, blah blah blah. And it's not the same as yours so stop perstering me and I'll sue for slander if you say it's like yours blah yadda yadda..."

That was unexpected, it's not like I'm unknown around these parts and it sort of reeked of paranoia/yes it is like mine. So, I ased politely again, saying I had no intention of publishing/copying the schematics, send them in password-protected PDF and then if they do get published with that PW I'm guilty blah blah blah. Then the second email came much like the first, a lont rant about I don't even remember.

OK, fine. When it was available I got one and guess what? It was nothing like my design. But all of this could have been easily settled with 1 email and then forgotten about in like 5min.

I think it's odd about the way people try to be evasive for no reason at all.

The 'decent' side of us has an expectation that if we publish something useful and Company X want to "commercialize" it, they come to us first and offer something. If we turn them down we expect them to honor our wishes. If we offer royalty then payment is expected. It's called "playing nice". It has no legal basis, it has a "nice" basis.

But then again, like I said: there is no expectation that this will happen. It should happen but not in this world as we know it. The person that publishes has to understand there is a good chance no $$$ benefit will occur.

The one case I like to cite is by John Candy (no, not the fat dead guy). This J. Candy was the inventor of 3rd order sigma-delta modulation used in every audio DAC and ADC for the last 20 years. He could have patented it and would be a mullti-millionaire by now. But he made the decision to publish it in the IEEE Journal of Solid State Circuits because he wanted the technology to procreate and be a 'game-changer' which it certainly was. There were early, unstable and expensive implementations (delta-sigma modulators since the mid-60s) but the "Candy loop" paper mathematically expalined how to actually build one in an IC.

If BL and IF want to send me the schematics I will be fair and impartial. And I promise not to steal them"


Muff Wiggler Posted: Sun Jan 01, 2012 8:40 pm [Muff owner]

"Blue Lantern has made it clear to me that he has no interest in participating in this thread any longer.

He insists that there is 'nothing illegal' about this work.

I cannot judge either way.

I am torn between defending work that feeds our community, and preventing un-founded IP bullying.

I don't know what's going on in this case. One side is willing to present their evidence, the other is not.

What has tipped the scales in this case is the anti-community and belligerent attitude by Blue Lantern. This attitude is poison and it's not welcome here. This thread is done."



Update: As Cynthia ( was mentioned regarding her Zeroscillator, I forwarded the post to her. The following is her response posted with permission:

"Through the Looking Glass...
It's one thing to make a through-zero circuit that will make some interesting sounds, but so far, I have yet to see any ~ precision ~ in the behavior of the Blue Lantern design. Tracking across a wide range with any type of accuracy whatsoever is a killer of a challenge, and especially without the usual waveform collapse exhibited by most through-zero attempts. (Just the wholesale loose parts for our Zeroscillator cost us More - than B Lantern's final retail price, and it is the precision in such a design that quickly drives up the costs)... So if the similarly named B. Lantern ZTVCO, is a copy of Ian Fritz's TZ VCO, then it seems it would be a poor copy at that? Just the close similarities of the name to Ian's is unimaginative, rather rippish, and insensitive. If Lantern cannot respect so much as the name of Ian's module, then what makes us think that respect for the circuit itself might be any different?

I'd like to thank Paul Schreiber for his usual clarity and agree that Paul pretty much summed-up the situation perfectly. Lantern's twice hostile response could be far more professional and respectful, and it certainly is not helpful to anyone. This is a serious charge being made of Blue Lantern's copying of someone else's hard work. I do believe that out of decency, and in kindness, we all should actually look past BL's initial response, and give him one last chance to simply be real with us, more honest and humble if possible, and extremely specific. He may be in the clear, please let us give him the chance.

'[asterisk wrote: 'so if your TZ core is a new concept (and i believe it is), did Cyndustries Zeroscillator steal your TZ core? or is that a different design? i've seen or heard no mention of your name in regards to the Zeroscillator.']'

I have to say that asterisk's question is quite fair and valid in this discussion... No Problem.
Mark Barton and Ian Fritz are lifelong ~circuit junkies~ who would probably rather study every single schematic, on every single page, in an electronic circuits Encyclopedia - than even have sex or eat chocolate! They know circuits upside down and backwards, and being consummate Engineers with this deep type of analog knowledge and experience, it becomes a Huge matter of personal pride for them to think differently and create unique designs of their own!

In the nine or ten months of constant engineering sessions, it took three of us working pretty much Daily to design the Zeroscillator. It was a huge undertaking and we did plenty of homework researching every schematic for through-zero oscillators, and triangle core VCOs that we could find. We did this specifically to ~avoid~ stepping on anyone's toes. I spoke with plenty of designers over the years including Don Tillman, Rene Schmitz, Ian Fritz, and I even contacted Bernie Hutchins at Cornell University to discuss the project to make sure we were on the up and up about all of this. We all compared notes together, because that is how it is properly done.

Yes our Zeroscillator is a triangle core, and not a saw, sine, or trapezoid design. Our design is different and not simply a hack or add on of someone else's work. I have personally paid over forty-thousand dollars to designers in royalties on our products and will certainly defend our intellectual property thoroughly if infringed. No one's work should be ripped off.

Is the Blue Lantern a Rippo? Ian seems to be certain of it, (and he would absolutely not suggest such a thing unless we was pretty damn certain. I consider Ian a gentleman and accept his verdict with complete confidence).

We greatly respect brilliant designers, even creating our Tribute Series with the honor of having their permission and then printing their names on our front panels so there was no question, for example, we secured permission from Jurgen for his Wasp design while others did not, and helped to popularized the Tribute module concept itself, along with an industry wide sense of fair play.

Perhaps more importantly, I have too much respect and belief in myself to copy anyone else's work. I would gladly submit our schematic for review to either Matrix or to Paul Schreiber because they are both genuine, and extremely professional.

Just like us, years are devoted to this work, and there is far too much at stake to fool around with any shenanigans to make a quick buck. Let Matrix or let Paul Schrieber see the Lantern Schematic and judge for himself, I personally have no problem with submitting our own, and let us offer an opportunity to Blue Lantern to redeem himself."

Update 7/16/12 (cross posted here):

For the time being Bluelantern's items will no longer be featured on this site. This is a follow-up to the BLUE ZTVCO DRY DEMO & Surrounding Controversy post.

via Ian Fritz on Muffs:

"Here is an illustration of the Blue Lantern Blue VCO, with inked-in sections indicating the correspondence of this circuit to the Teezer Thru-Zero VCO. For the VCO core and sync sections, the two circuits are virtually identical. The only notable difference is the trivial substitution of an LM13700 OTA, along with substitution of low-performance op amps. Otherwise, circuit topology and component values are exactly identical, even down to and including the number and values of all bypass capacitors.

As discussed before, the +/- 5V supplies were taken from Rene's TZ VCO. They consist of three-terminal power supply regulators, rather than the precision reference components of the Teezer. Otherwise, the multiple power supply voltages are derived exactly as in the Teezer. The waveshapers -- external to the core -- are a different design.

Hope this helps clarify matters regarding the Blue Lantern "design". I hate to be still beating on this, but we are still hearing negative comments from the skeptics.


via Adam Vavrick on The MATRIXSYNTH Lounge

Bluelantern is banned on Muffs. I will see if he has any response to this.


  1. What are you trying to achieve buddy,the one he sells now is not a clone at all.

    He will sell them anyway because it has the same features at bargain price.

    The fritz diy version pcb is too big.

    The BL version brings the features of a true TZ vco in eurorack format for a competitive price.

  2. Ian place copyright logo together with his name on schematics he drawed where he mention to have used circuits from electronotes in his schematic.

    Thats stealing,admid to have clone it and claim ownership lol (everyone can check that ,just go to his site)

    He should look at himsef first before accusing others w/o any proof...

  3. To tesl@ - electronic circuits do not fall under the scope of Copyright Law. You are confusing the matter. If you draw a design, write a description, or any such thing in a document (for example, let's say a PDF document) then that PDF document is protected by copyright, not the concept of the electronic circuits within. That requires a patent.

  4. Ian's design is not a copy of the Electronotes work, in fact, Ian was a regular schematic and design contributor to that forum starting over thirty years ago, so it becomes "chicken or egg" at this point.

    Secondly, how is it that you can claim any knowledge of Blue's circuit whatsoever, did you design it, or might you actually be Blue - sock puppetting under an alias? We are trying to be as reasonable as possible and your uninformed comments are not helpful in this case.

  5. I never said his TZ is taken from EN,if the target is to destruct a manufacturer ppl are good into modifying information,clearly can see on what your mind is focused..
    I sugest to shipp your ZO's asap ppl payd for years ago instead of contributing to the destruction of BL, go solder now..

    Jabrockson,its abouth that ian took himsell stuff from others for some of his circuits..
    So if its the case the BL ZT has his foundations on ian's version there is no reason to boycott to start with..

  6. Well thank goodness we have the definitive answer from You, Stranger!

    I was mentioned above and was asked to put my two cents in. Now I' have and don't really have any more to add. Thank you for your comments.

  7. Here are some interesting facts. Some are claiming that the only way to get a teezer schematic is that you have to buy a bridechamber board and then they email you the pdf. Nonsense, the documents were made public for the longest time.

    Now the html page is gone and a hole lynch mob is chanting ...stolen, stolen, stolen.

    I can understand Mr Fritz has a right to put stuff offline but for others to say stuff was stolen is obsurd.

  8. There are a couple of places on the above clip eg, at 2:13 where you can hear a noisy kind of random static. That shouldn't be there. Why is it there? Because of the component substitutions made in the design. How do I know? Because it's my design and I spent months and months getting rid of all that garbage. I know this circuit like the back of my hand. Buy this and you will get less than you paid for.

    The URL for the documentation was private and intended only for people who purchased boards. There is no need whatsoever to give full attribution for a schematic in a private instruction manual.

  9. Mr. Fritz I don't think the area was private. Maybe you meant for it to be private in your heart, but It was easily accessible. You had it under Miscellaneous links & for the longest time. You had all your projects for public view. I still have the cache of your pages. I took a snap shots:

  10. I still have your pdf's. It is true, it was available for public download. We all have them.

  11. Oh, it looks like you put the 'misc_lnk.htm' page back in action. But you decided to hide the pdf's from public view. I just checked this a little while ago. Mr Fritz are you trying to cover your mess? or make it look again like 'something was stolen'. PRIVATE YOU NEED A PASSWORD.

    "noisy kind of random static. That shouldn't be there." Kinda like your missing pages?


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