Jose EB5AGV

Well, things are not easy with the Venom! After the apparently good test of +/- 9Vdc generation (without any load), when I got from Mouser the replacement OPAMPS, just installing one on the PCB made the switcher go nuts. So the OPAMPS were not the root cause!. Oh well... I had to replace again the switcher IC, as even with limited current from the lab power supply (set to 9V/0.5A), it failed while trying to find the problem. Also, I was not sure about that switcher IC being not a counterfeit, as the labelling was almost invisible after cleaning, and the surface was rough. So I ordered legit ones from Farnell and did, again, the replacement work (note: they are 3x3mm, I wrote before 5x5mm) These are the good ones: Here you have it replaced... the small added wire is because one trace was damaged and this wire bridges the missing connection, luckily the same than the adjacent one: It seemed to be better, but still with just an OPAMP installed, the negative voltage (-VA) decreased from -9Vdc to about -4Vdc and the IC got pretty hot. I found the service manual for the Venom online and traced on the schematics all and every point the -VA voltage was present. I discarded all and every componet (capacitors, diodes) on the circuit. All were fine!. SO I removed the only OPAMP on the circuit... and -VA was fine again 😳 Then... what if the switcher circuit had a problem?. I checked the coils and, BINGO!, one of them, L2, was shorted. Oh my!. That explained while, under any load, the switching of a basicalle short load, got the switcher transistor for that rail pretty hot. Basic electronics 🤣! Now, well, such a miniature SMD 10uH/0.49A coil was sure not on stock on my lab... But, well, I was not going to wait for another components order, so I built them with some suitable toroids. I selected the T37-43 ones, as 5 turns would be enough to reach 10uH, according to an online calculator. Here you have the contraption, first measured and then installed (I replaced also the adjacent coil, as it seemed also slightly damaged): Now the test!. FIrst +VA Then -VA At long last!. I added the other four OPAMS and it kept working. I added some glue to keep the coils on place: And this is the overall view of the finished board: More to come soon! Jose

I hope my MODX6+ qualifies... I bought it to save weight on weekly rehearsals, as taking my MONTAGE 6 each week to the rehearsal was just impractical. First, I hated the keybed and there was no way I would use it on gigs... But, you know, human beings are adaptable 😬. So, after a couple months of rehearsals with it, I got so used to it that, on next gig, I took it. And, since then, my two MONTAGEs are enjoying kind of a sweet retirement at my home studio, while the heavy load is taken by the MODX6+ So, well, I still prefer by large the MONTAGE 6 keybed, but for sure can play decently on the MODX6+ and the weight and size difference makes it very easy to schlep. It seems I am getting old! 🤣

And then, thanks to the geniuses who delivered Brexit, you need to pay more taxes if you buy from any Europe country outside the UK. And it is not a minor thing: in Spain it would be about 21% VAT plus import taxes (I guess about 8%). Add shipping and then we are talking close to 20.000€ 🤯

Well, the switcher IC arrived yesterday and I installed it. Not a nice experience due to the soldering... It is a very tiny IC (about 5x5mm), with no pins on it, and a big ground area which makes soldering harder: This is the bad one: Kapton tape used to protect adjacent components: After some soldering and cleaning work (there are two pins joined by a trace on the PCB, is not a fault), here you have the new IC placed: Then the test, using a lab power supply, set at 9V 0.5A maximum... And the switcher generated positive and negative voltages, but not the right ones 🤯. It seemed like a problem on the ICs powered by this power supply. And, finally, I found there was a failure in one of the connections of the replaced IC and so the positive output had gone too high... And no less than 5 double opams had died (luckily, all same type). Oh well... I removed them, soldered another switcher IC (as it was just impossible to get the soldering right), and now I have +9 and -9Vdc 🥳 One of the damaged opamps: Now I am waiting for the replacement opamps to arrive. Let's hope once replaced (will do it one by one and recheck voltages carefully each time) the Venom will finally generate some noise! 😅

This is the third forum at least that you ask exactly the same... Why don't you take some time to learn synthesis?. You have been already given advice on that elsewhere (Sound on Sound tutorials) Trying to find shortcuts won't help in the long run, trust me PS: down-voting this won't help you to LEARN, which is what you seem to be avoiding at all means, looking just for an easy, no effort answer

I have had another hobby since I was a boy, electronics. It specialised in amateur radio and test equipment gear and I collected and fixed tons of related things for decades. That was the starting point of my 22 years of R&D work and also of my current electronics home lab (already for 12 years), where I develop my current job. So I can't really be angry about all those things which helped me to build my career. But, as happens with old synths, younger people just don't care about those nicely built HP / Tektronix/ Marconi ... generators, oscilloscopes and analysers, built to last using the very best materials, as gold plated PCB contacts, Teflon covered coaxial wires, heavy aluminium cast chassis and such. So now I have a warehouse full of yesteryear electronics which nobody but I seems to care about 🤔 It is not just for the large amount of money I have spent on that gear, which in perspective is as money burnt, but the lack of appreciation by my children / wife and by people in general, makes me sad, as the only way out is to trash most of it. I hope my growing collection of music gear does not end in a similar way. I am mostly interested on 80s plus synths (lots of them bought faulty and fixed by me) and accessories (well, and also some guitars, electronic drums, EWIs, amplifiers, ... 😬). My idea is to clean up the currently area full of radio and test gear and convert it into a music studio plus storage area for music gear. At least I will be able to use it and, in the future, my heirs can do what they wish with all of that (I hope it keeps some value so they can cash it, but don't lose my sleep for it 😅) Anyway, what would be of us without our toys? 😉

Just 50 units available, hurry up! 😅 Seriously, it seems like a good thing, kudos to them!

My second daughter lives in Switzerland... Time to pay a visit 😅

I would keep the Arturia MkII, as the action and controls are pretty good, and you keep a second keyboard which can be useful as B3 manual or just for another instrument

@JoJoB3 are you OK?. Why do you keep doing this (thumbs down here and there)?. Sincerely curious, don't see the point

Bert can make an 80s low end Casiotone sound like a top-notch workstation, that is not fair 😅

I own all four Refaces, bought used, as new prices were IMO too steep and was more a curiosity than anything I could use regularly. All but the CS were bought in working condition. The CS was just 100€ because it didn't boot up... A firmware install fixed it 🥳 Well, I think there won't be an update to that series. They were an interesting concept, but somewhat flawed. For me the CS is a good tool to learn basic synth concepts. As a performance synth I don't see it. The SoundMondo thing is also interesting, but seems underutilized. I have found good sounds there for the series. All in all, I guess Yamaha is just discounting an "old" product, not making space to a new version. But time will tell!

Some background: due to my work, I am about 8 hours a day on my electronics lab at home, were I have setup a monitor in the middle of the workbench, recessed so I can place the item I am working on in front of it (the bench is 1.2m depth). This lets me see the technical documents (schematic, PCB component locations, data sheets...) on it. But once the problem has been located, while I do the mechanical work, I can watch (well, sometimes mostly listen) any interesting YT video. During last years I have watched some thousands of mainly music related videos that way. So, for me, a good ad blocker is a must. The problem you describe at the beginning of the videos happened for some time, but lately (perhaps a year or so) is gone. At least with Firefox plus uBlock Origin (uBO) There was some fighting between ad blockers (uBO was very active on this) and YT during several months, as YT detected them and advised you could lost access to their videos, slowed loading and such. But the blockers modified almost instantly the code to prevent detection. After some months, YT has recently stopped doing that. Let's see what is next!

You can use uBlock Origin extension in your browser and forget those pesky ads in YT 😬

Just another synth project on the repair bench! (details on the Repair sub-forum) M-Audio Venom

Those original SD cards seem to be very prone to fail. Maybe is related with the battery getting depleted and, at certain voltages, causing havoc to them

Well, note that the image is zoomed. And also, if you look in same detail to the big ICs soldering, the quality is not very good. I would think that chinese PCB manufacturer is not that great (as, as you can imagine, this unit is Made in China) All in all, the synth seems good enough to be fixed. Let's see what happens when the +/- analog supply voltages are back! 😁

I can relate to that 😬

Do you, or someone else, know if that action is the same than the one on the CTX-5000/3000/800/700?

It seems more like a reworked board after production (*). The unit seemed unopened, and I am very used to find small details which show an electronics item has been tampered with (as tiny marks on screws, displaced wiring, pen marks, cabling or connectors dents, ...). So maybe the PCB production was of questionable quality to begin with. As the unit seems to work, except for the audio output (which without the +/- analog power supplies is expected), I am moderately confident it will work once the switcher is replaced. Let's see! Jose (*) Back when I worked on a company which manufactured electronics, there was a full line of workers who just checked new manufactured circuits, fresh from the automated production lines, and reworked any suspicious solder point. That is what could have happened here, IMO

Well, it seems my guess was not far from the truth!. I have checked and there is a switching regulator which gets burning hot and there is no proper positive nor negative output voltages from it (is a dual voltage regulator). It is marked LBHM and corresponds to a LT3471. So a replacement has been ordered. More to come!

Well, I have finally opened the box... and here you have the first pictures of it. At least it powers up: Venom... good name! Once you remove a ton of screws and the keybed connector... Once the keybed is removed, you have the electronics attached to the top cover: And on this board should be the problem. I have already checked all capacitors but, sadly, they are OK, so it won't be a simple fix: The unit generates a faint sound, barely audible at maximum output and monitor levels, which is promissing. Next steps are to check internal voltages (it seems to be a switched power supply on that board), follow the signal from LINE OUTS to the D/A, and try to find the fault on that path. There seems to be no schematics available. I will try to contact M-AUDIO, but don't have high hopes. All in all, another interesting project ahead! Jose

Exactly same date, but 28 years later than my marriage (20/10/90). There was just 1/365 chance of being that way 🤩 I didn't play that day, thought... I was about 28 years to begin playing... exactly in 2018!. Two coincidences 😅

Well, I can't resist when I see a cheap, not working synth... Last week I saw an M-Audio Venom, in apparently good shape, sold as "only MIDI controller, unknown fault". It was 75€, shipped, so I pulled the trigger. It arrived yesterday but won't have time to even open the box until tomorrow. But I couldn't resist to open this thread, just in cause someone has gone already this way 😅 More to come! Jose

Here in Spain the unusual is to find a piano in a church, at least on the predominant Catholic ones. You can find tube organs in some larger ones, and electronic organs in others. But acoustic pianos are not usually found. In fact, I am trying to remember any church around this area with a piano, and can't remember any. So, yes, it seems a cultural thing 🤔